essay on nature and trees

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• Tree Essay for Students in English

Essay On Tree

We live in an ecosystem with other living beings. One of the most pillars of an ecosystem is the trees. The green living beings provide us with the oxygen we need to breathe and live. Trees process carbon dioxide and use sunlight to make their food. In this process, they release oxygen that every other animal needs to live. Trees provide more benefits and make our planet sustainable. Despite such benefits of trees, we are deforesting the green reserves for our profits and slowly killing the planet.

Trees are the big plants that have a green hood of foliage. A tree provides us with shades in the hot days. The cool shade relieves us from scorching heat so that we can rest. We find them in the big parks and roadsides of well-planned cities. We find many trees in rural areas. This is why the air we breathe in the villages is very clean. Trees have the innate properties to clean air by absorbing carbon dioxide during the daytime. They have the biological power to convert carbon dioxide into carbohydrates using the power of sunlight. This is what we depend on. The entire ecosystem depends on what plants produce. An ecosystem depends on these producers of the food chain. These producers support the life of herbivores and the rest of the animals in the chain.

There are so many types of trees we find in nature. In fact, we are not aware of all the species found in the darkest and deepest jungles on the earth. These trees breathe in carbon dioxide and release oxygen. This oxygen is then used by the animals across all ecosystems. It means that the trees are the prime life support we need to survive. Trees are also responsible to remove carbon dioxide, the prime greenhouse gas that contributes to global warming.

Global warming is caused due to the over-accumulation of greenhouse gases in the atmosphere. Aggressive industrialization is creating more greenhouses gases that trees can absorb. On the contrary, we are destroying our forest reserves to find more land to construct concrete jungles and factories. It has become a huge burden on the existing forests on earth. It is a natural cycle where the trees absorb the carbon dioxide animals produce and release oxygen for them.

When the trees are falling short, the level of carbon dioxide will automatically increase. It is resulting in a steady increase in the average temperature of the earth’s surface. The entrapment of heat released by the earth’s surface by the blanket of greenhouse gases is causing the ice caps in the mountains and poles to melt. It is endangering the marine species, coral reefs, islands, and associated ecosystems. In fact, trees also keep the earth’s surface cooler by providing shade. Humans are responsible for the destruction of the forests and slowly making the planet inhabitable for other creatures.

The level of pollution is also increasing in the entire world. Trees are the only creatures that can save us from the alarming rise in the level of greenhouse gases. They can only provide shade to the needy. It is we who need to understand the importance of trees and plant more. We need to afforest barren lands and stand against the illegal acquisition of forests for industrialization. The entire world needs to slow down in terms of consumption. This pressure on every industry is driving us to gather more resources. We are steadily depleting all the natural resources and will run dry soon if we don’t stop.

We need to bring change. We need to make everyone aware of how trees are important for survival. It is us who can make a cumulative decision and trees can help us achieve a healthier planet for all living beings.

Trees are essential for human survival as well as the ecosystem's survival. Life would not be possible without Trees. Trees provide two of life's most important components: oxygen and food. As time went on, we began to collect Trees for medicine, shelter, and other commercial objectives. Our reliance on Trees has not decreased throughout time. In reality, we rely on Trees more than ever before.  The purpose of this essay about the importance of Trees is to inform readers about how important Trees are to the environment. We've started chopping down big tracts of forest to make way for more people because our needs are so tremendous.

Trees purify the air we breathe, they are our best companions. They also purify the water and soil, ultimately making the planet a better place. People who live near Trees are also more fit, healthier, and happier than those who do not.

Furthermore, it is our job to care for our friends who assist us in a variety of ways. Most importantly, by protecting plants, we are primarily benefiting ourselves rather than the plants. Because the lives of Trees and plants are not dependent on us, but our lives are dependent on them.

Trees must be protected because they are vital to our ecology. Furthermore, Trees are considered natural carbon sinks, which means they have the ability to absorb and store carbon dioxide from the environment. This reduces not only the amount of carbon dioxide in our atmosphere but also the greenhouse effect's influence. As a result, Trees provide a number of functions, ranging from ecosystems to environmental cleaners. 

Trees are the earth's green gold and the source of life for all living things. Trees are the source of life. They are wildlife habitats in their natural state. They are also a part of the natural beauty of our surroundings. Nature is vital to our survival. Trees are the most attractive and important aspect of our environment. Nature's equilibrium is linked. A single dysfunction disrupts the entire environment, causing harm to all living things.

It is necessary to explain the many sorts of Trees when discussing Trees. Trees are available in a wide range of shapes and sizes. Shrubs, creepers, hardwoods, and other plants are among them. As food, certain soft Trees. Pumpkin, squash, water, spinach, and other vegetables are examples. All of these green Trees are beneficial to our well-being. Mango, jackfruit, coconut, and other tropical fruits can be found later in the hardwoods. Rose blossoms, guava Trees, and other bushes can be seen among the shrubs.

FAQs on Tree Essay for Students in English

1. What is the importance of trees?

Trees are extremely significant to us in a variety of ways, and we cannot overlook their significance. They are significant because they provide us with clean air to breathe, food to eat, and protection from the sun and rain. Aside from that, there are other medicines on the market that contain tree extracts. Aside from that, there are plants and trees with therapeutic properties.

They bring calm; they produce a lovely and restful atmosphere. They also aid in the reflection of the sun's damaging rays and the maintenance of a comfortable temperature. They also aid in water conservation and soil erosion prevention. They help control the ecosystem, and several plant species have been venerated since ancient times.

2. What is the value of trees?

When a plant or tree seed grows, it greens the environment around it. It also supports a diverse range of living types. Many reptiles and animals dwell on or around it, and birds build their nests there.

Aside from all the lovely flowers, there's food growing on it. Furthermore, many tree parts, such as roots, leaves, stems, flowers, and seeds, are edible. Most significantly, they never expect anything in exchange for their services or gifts. Trees also help to maintain the ecosystem and ecology's equilibrium.

To sum up, trees are extremely important and beneficial to all living things on the planet. Without them, life on Earth will struggle to survive, and after a while, every species will perish due to a lack of oxygen on the planet. So, in order to save our lives and survive, we must learn the value of trees and pass this knowledge on to our children.

3. What are the benefits of trees?

Trees give us several benefits, some of which we cannot see but which have a significant impact. They aid in the fight against climate change by absorbing greenhouse gases, which are the primary cause.

They also recharge groundwater and filter hazardous chemicals and scents from the air. They're also nutritious, with the king of fruits, the 'Mango,' growing on trees.

Furthermore, they are the source of rainfall by attracting clouds to the surface and causing them to rain. They have the potential to be teachers, playmates, and role models for unity in diversity.

Above all, they are a good way to reduce pollutants in the air, water, and noise.

4. What are the important highlights of the essay on trees?

Essay about the Importance of Trees in 10 Lines

Trees are vital to the ecosystem because they absorb carbon dioxide and release oxygen.

Trees come in a variety of shapes and sizes, with thousands of varieties to choose from.

Trees provide food and shelter for animals.

Trees provide benefits to humans in a variety of ways.

Trees are also used to manufacture furniture and other industrial products, and they are a major source of medicine.

Trees and their branches are utilised as a fuel source. Trees also help to avoid soil erosion. Trees help to avoid flooding and clean the air we breathe. Trees must not be taken down, and additional trees must be planted.

5. What are the community and ecological values of trees?

Value to the Community

Our parks and gardens have been ornamented with trees and other vegetation, creating attractive aesthetics for the surroundings. Furthermore, trees provide shade, which is particularly beneficial during the summer. The presence of trees and other greenery increases the value of a residential neighbourhood. Moreover, trees that are several hundred years old serve as tourist attractions or historical markers. In Bangalore, for example, a tree known as the Dodda Alada Mara (Big Banyan Tree) is a famous tourist destination. This 400-year-old tree is the largest of its kind, covering about 12,000 m 2 .

Trees Have a High Ecological Value

The planet would become desolate and dead without trees, which is why they are so important to the ecology. There are also a variety of animals that live in trees. Arboreal creatures spend their whole lives, including rearing their young, dining, sleeping, and mating, in trees. If trees are cut down, these animals will have nowhere to live, and they may go extinct. The species that live in the trees include sloths, flying snakes, geckos, koalas, opossums, and tarsiers. Hundreds of spider and bug species have made their homes in trees.

6. Why are Trees important?

Trees are the base of a pyramidal ecosystem and food chain. They are the online living beings that can trap sunlight to make food and the rest of the creatures depend on it directly or indirectly. Trees cannot be replaced with anything in any biome. The sustainability of nature depends totally on trees and partially on other animals. They also consume carbon dioxide and keep our atmosphere free from toxic gases. We also inhale oxygen released by the trees during photosynthesis. Hence, trees are the most important living beings on our planet that make us sustainable.

7. How Trees can prevent global warming?

The increased rate of industrialization is generating carbon dioxide at an alarming rate. This is hampering the balance of the atmosphere causing global warming across the planet. Only trees are capable of absorbing carbon dioxide at a huge rate and release fresh oxygen for other creatures by the process of photosynthesis. This is how we can reverse global warming in a natural way. By planting trees, we can tackle this huge threat and save the only habitable planet we have.

8. How Trees help us apart from giving oxygen?

Trees and plants hold on to the soil and stop soil erosion. In fact, trees in the coastal regions and river banks are capable of reducing the destructive degree of floods and tsunamis. Trees are also the home of wild animals that are a part and parcel of an ecosystem. We also depend on the crops to sustain. Many trees have medicinal values.

We get wood from trees to construct our homes. In a nutshell, trees are very important for every living being on earth.

Essay on Trees for Student and Children

Trees, the majestic giants of our natural world, play a vital role in our lives and the health of our planet. In this essay, we will explore the countless reasons why trees are so essential to our environment, well-being, and the future of our planet.

The Oxygen Factory

Trees are often referred to as the “lungs of the Earth” because they produce oxygen through a process called photosynthesis. Did you know that a single tree can provide enough oxygen for two people for an entire year? Trees are the primary source of the air we breathe.

Carbon Dioxide absorption

In addition to producing oxygen, trees absorb carbon dioxide, a harmful greenhouse gas that contributes to climate change. They act as Earth’s natural air filters, helping to regulate the Earth’s temperature and combat the effects of global warming.

Habitat for Wildlife

Trees are not only essential for humans but also for countless species of animals. Forests and woodlands provide homes and shelter for a wide variety of wildlife, from birds and squirrels to larger animals like bears and deer. Without trees, many of these creatures would lose their habitats.

Biodiversity Hotspots

Forests are biodiversity hotspots, meaning they contain a vast array of plant and animal species. The rich diversity of life in forests contributes to the health and stability of ecosystems. Protecting trees means preserving biodiversity and the delicate balance of nature.

Food and Medicine

Trees provide us with more than just oxygen and shade. Many trees bear fruits, nuts, and leaves that are essential sources of food for both humans and animals. Moreover, trees have been a source of natural medicines for centuries, offering treatments for various ailments.

Soil Health

The roots of trees help prevent soil erosion by anchoring the soil in place. They also improve soil quality by increasing its nutrient content and helping it retain water. Healthy soil is essential for agriculture and food production.

Economic Benefits

Trees contribute significantly to the economy. The timber industry relies on trees for wood products, while the tourism industry benefits from the beauty and recreational opportunities that forests offer. Moreover, trees increase property values and energy efficiency in urban areas.

Expert Opinions

Environmental experts, such as Dr. Jane Goodall, emphasize the crucial role of trees in preserving our planet. Dr. Goodall advocates for tree planting initiatives and reforestation efforts to combat deforestation and its devastating effects.

Threats to Trees

Despite their importance, trees face numerous threats, including deforestation, wildfires, and climate change. Deforestation, the clearing of forests for agriculture or development, results in the loss of critical habitat and contributes to species extinction.

Our Responsibility

As stewards of the Earth, it is our responsibility to protect and preserve trees. We can do this by supporting reforestation efforts, participating in tree planting initiatives, and advocating for policies that prioritize tree conservation.

Conclusion of Essay on Trees

In conclusion, trees are not merely silent giants in our world; they are life-giving, habitat-preserving, and Earth-protecting wonders. They provide us with oxygen, shelter, and sustenance while maintaining biodiversity and combating climate change. It is our duty to recognize their significance and take action to ensure that trees continue to thrive for generations to come. Together, let us stand for the trees, our faithful allies in the quest for a healthier and more sustainable planet.

Also Check: How To Write An Essay

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Importance of Trees Essay - 100, 200, 500 Words

Trees are one of nature's most priceless gifts to us. Our lives are made easier by the items we can obtain from trees. It makes the entire globe more beautiful. The same goes for thinking of trees and life. We shall thus talk about the significance of trees today in order to emphasize their role in our lives.

100 Words Essay On Importance Of Trees

Both the ecosystem and human life depend on trees. Life would not have been possible without trees. We get food and oxygen from trees , two of life's most essential elements. As humanity progressed, we began to cut down trees for food, medicine, and other economic purposes. Our reliance on trees hasn't lessened even today. In actuality, our reliance on trees has never been greater. As inhabitants of the planet, it's our duty to inform everyone about the significance of trees and the need to conserve them. To accommodate the over growing population, we have begun clearing vast tracts of forests which in turn is harming the environment and people.

200 Words Essay On Importance Of Trees

Since the beginning, trees have given us food and oxygen , both of which are necessary for life. Life on earth is impossible without trees. Additionally, they give us food and medicine. Because trees meet the needs of contemporary living styles in communities and cultures, their value is increasing daily in the current era.

Everyone needs plants and trees to survive. Plants provide either all direct or indirect requirements for life. Fruits and medicines are produced by trees. Trees are the source of a wide range of different products, including wood, rubber, cotton, paper, etc.

Animals, insects, birds, and a variety of other living things call trees home. Trees produce food and contribute greatly to the ecology as a whole through photosynthesis. This procedure purifies the air and maintains a healthy environment.

Trees help water evaporate, which maintains the Earth's water cycle . The root systems of trees were designed by nature to prevent the soil below from being swept away by rain and floods. This prevents soil erosion and landslides from occurring.

We must understand how crucial trees are to lead fulfilling lives. People ought to cultivate at least five plants each year. The current situation demonstrates the necessity for increased tree planting in the world today. As a result, we must continue to plant trees if we want to live long and healthy lives.

500 Words Essay On Importance Of Trees

Trees are one of nature's greatest gifts . It is impossible to deny the importance of trees in the lives of all living things. They not only give us an infinite number of things, but they also create calmness and harmony in the earth. The survival of all life on Earth depends heavily on plants and trees.

Oxygen and Global Warming

For our protection, trees take in carbon dioxide from the air and exhale clean oxygen. This cycle supports other living things in this world. Carbon dioxide is a greenhouse gas. When released into the atmosphere, this greenhouse gas along with others creates a layer that traps solar heat. They cause the temperature of the atmosphere to rise. As a result, the planet becomes warmer. Thus, increasing tree cover will purify the air and lessen the impact of global warming.

Trees support a diverse, healthy ecosystem. A diverse ecology is created by the animals, insects, birds, and fungi that live in trees. At the bottom of the food chain, trees make their own nourishment. Through a process known as photosynthesis, they manufacture their own food and make a substantial contribution to the ecosystem as a whole. In addition, trees are a rich source of medications that are utilised in Ayurveda to treat disorders naturally.

Water Balance

Rainwater is captured by trees and stored in the ground. By doing this, clean water is kept from running and from wasting in sewers. Additionally, they serve as watersheds, holding back floodwaters for a while before gradually letting them flow into the ground and atmosphere. So they provide us with a water bed and preserve the area's water foundation. In order to prevent landslides and soil erosion, trees' root systems are so well designed by nature that they hold the soil below from being carried away during rain and floods.

Healthy Life

We receive clean water, food, and air from trees. Our stress is reduced by its freshness and greenery. It creates pleasant energy in the air. Additionally, trees offer cool shelters throughout the summer and during rain. Lush trees and environment contributes to a happier and healthier mood . Studies have shown that patients who come into contact with nature recover quickly. There are many benefits that trees offer us for a better quality of life.

Economy and Environment

Fruits and medicines made from trees are sold to many nations and contribute to economic progress. People can make a life by growing trees and selling their produce. Paper and wood come from trees which contribute greatly to many businesses and keep the economy running.

Trees also keep the environment natural and serve as a natural air conditioner in the heat. Trees play a significant role in our lives and the environment, providing a seamless service. We have somehow failed to safeguard them, which may be the reason why we are currently experiencing the negative repercussions of deforestation, such as severe pollution and global warming. In order for humans to exist in our world, trees must be well-cared for. We ought to inspire others to grow their tree populations. The sooner we realize this, the better it will be for us because it is for our own good.

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Importance of Trees Essay for Students and Children

500+ words essay  on importance of trees.

Trees are very important, valuable and necessary to our existence as they have furnished us with two important life essentials; food and oxygen. Apart from basically keeping us alive, there are many other little and big benefits we get from trees. So, trees are vital resources for the survival of all living beings. Therefore, Governments world over and many Organizations are taking steps to prevent deforestation and to tell the benefits of planting trees . Let us go through some important points about the Importance of trees for the existence of human life.

Oxygen and Global Warming

Trees intakes Carbon dioxide from air and breathe out fresh oxygen for our life support. This cycle is made by nature to sustain other living beings. Further, the Carbon dioxide breathed in by the trees is one of the greenhouse gases. This and other greenhouse gases, when released into the atmosphere form a layer and trap the heat from the sun. They result in an increase in the atmospheric temperature. This causes global warming . So planting more trees will clean the air will reduce the global warming effect.

Trees contribute to a rich healthy ecosystem. Animals, insects, birds, and fungi make their home in the trees and make a diverse ecosystem. This balanced environment, in turn, contributes to the betterment of human beings. Trees produce their own food and are found at the bottom of the food chain. They produce their own food through a process called photosynthesis and contribute significantly to the whole ecosystem. Further, trees are a rich source of medicines that are used to heal our diseases in a natural way as done Ayurveda.

Water Balance

Trees receive the rainwater and hold them in the land. This prevents clean water from flowing and getting wasted in drains. Along with it they also act as watersheds and hold the floodwaters for some time before slowly releasing them into the earth and atmosphere. So, they maintain the water base of an area and provides us with a water bed. The root system of the trees is so well made by nature that it holds the soil underground from getting washed away during rain and floods thus prevents landslides and soil erosion .

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Healthy Life

Trees provide clean air, water, and food to us. Its greenery and freshness also act as a stress reliever for us. It gives a positive vibration in the atmoshphere. Trees also provide cool sheds during summers and during rains. Children also develop good memory when surrounded by green trees.Patients recover easily when comes in contact with greenery. There are a lot more things that tree provides us for ou better life.

Economy and Environment

Trees produce fruits, medicine which are exported in many countries thus helping in economic growth . Cultivating trees and selling their product helps people earn their living. Trees provide wood and paper. It also acts as a natural cooler in summer thus reducing Ac bills and keeping the environment natural.

Trees have a lot of importance in our lives, and it provides seamless service for the environment. we have somehow not protected them and perhaps that is why as on today we are being affected by global warming, severe pollution and other ill effects of deforestation . Trees should be treated and nurtured nicely so that human beings can survive on this planet. We should encourage others to plant more and more trees. It is for our own betterment and the sooner we understand this the better it is for us.

FAQs on Importance Of Trees Essay

Q. 1. Which is the largest tree in the world?

Ans: General Sherman, a giant sequoia, is the largest tree (by volume) in the world, standing 275 feet (83.8m) tall with 52,000 cubic feet of wood (1,486.6m).

Q.2. How much water can a large tree intake in a single day?

Ans: In one day, one large tree can lift up to 100 gallons of water out of the ground and discharge it into the air as oxygen and water vapor.

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Essay On Trees – 10 Lines, Short And Long Essay For Kids

Key Points To Remember When Writing An Essay On Trees For Lower Primary Classes

10 lines on trees for kids, a paragraph on ‘importance of trees’ for kids, short essay on trees for children, long essay on ‘importance of trees’ for kids, what will your child learn from this essay.

Trees are a part of the Earth and exist to enrich our lives. They are critical to the survival of every living species, including land animals, wild creatures, and aquatic organisms. Raw materials provided to us by trees have been used since ancient times to make herbal medicine. The leaves, roots, and stems are parts that are high in medicinal properties and can be used to make natural tinctures. The air we breathe is not clean these days, and this is where the importance of trees comes in. Below we have provided the best tips on writing an essay on trees for classes 1, 2, and 3.

Trees don’t exist just for show. They preserve our environment and give life to the wilderness. Many animals dwell on lands shrouded by trees and base their survival on these natural habitats. If it’s your first time learning how to write an essay on trees, here are a few pointers:

• Write an introductory paragraph on trees and discuss how trees brought life to this planet.
• Discuss the different types of trees in urban settings, such as woodlands, rainforests, and perennial plants.
• Mention the benefits of trees for our health as humans and how they play a role in preserving nature.
• Add a conclusion near the end and summarise why trees are essential for us.

As human beings, we should definitely do our share for the environment and attempt to plant more trees. Here are some points to write an essay on trees for classes 1 and 2:

• Trees produce oxygen for our environment and absorb harmful carbon dioxide gas.
• Without trees, there would be no life on this planet.
• Our ancestors used tree wood to forge weapons and hunt in the past.
• Every person should take the responsibility of protecting trees and ensuring their integrity.
• Trees help discard water, noise, and air pollution.
• Many natural disasters can be prevented worldwide by planting more trees.
• Trees give us fresh fruits, seeds, and seasonal bounty, which we can enjoy.
• Trees improve the fertility of soils and help prevent soil erosion.
• The earth will turn into a barren wasteland if all trees are destroyed, and no life will exist.
• Travellers rest under the shade of trees to relax and rejuvenate during hot summers.

Trees make our world beautiful and give us food to eat. The fresh air we breathe is from the trees; mother nature would not thrive without trees. Below is a short paragraph on the importance of trees for kids:

Trees are the breathing lungs of the earth. We need trees more than they need humans. Industrial factors, cars, and human activities produce carbon dioxide emissions that harm the environment. The high amount of carbon dioxide in the atmosphere results in air pollution and increases the chances of global warming. Trees absorb carbon dioxide gas from the environment and purify the atmosphere. Without trees, we would lack enough oxygen to sustain life on the planet. Many herbivores and wild animals turn to trees to seek shelter and food. Trees’ fruits, nuts, and seeds are used to feed these animals. Trees also help fertilise the soil, maintain mineral composition, and prevent it from eroding.

Trees are our best friend and are considered nature’s bounty to human beings. They provide us with food, shelter, raw materials, and natural resources. We need oxygen to live; without trees, all life would cease to exist. Here is a short essay for classes 1, 2, and 3:

Tree plantations ensure our environment does not run out of a decent oxygen supply. Global warming is becoming a problem, and the ice caps are melting because of too much air pollution. Trees absorb harmful toxins from the air and purify the atmosphere. We can say that trees are more valuable than gold, silver, and money because oxygen is essential for survival. There is no price or value we can attach to trees since they cannot be replaced. Many beautiful birds, wild creatures, and insects use trees to serve as their natural habits. Trees are crucial as they provide raw materials for making vital medicines, beauty products, furniture, etc. Most trees can be classified as Angiosperms and Gymnosperms.

Angiosperms make flowers and seeds, while gymnosperms do not. Unlike gymnosperms, they cannot reproduce without the help of animals and depend on them for spreading their pollen. The leaves of trees can absorb a significant amount of heat, and they act as nature’s filters when it comes to cleansing the air. More trees in our environment mean a lesser amount of dust, toxins, and harmful substances.

One of the best ways to deal with climate change on our planet is by planting trees. There must be increased recycling efforts, and millions of people worldwide should work together and plant more trees. Here is how to write a long essay for class 3 kids on trees:

The importance of trees cannot be negated in our lives as they are one of the reasons humanity can survive on planet earth. There are various types of trees found in nature that are useful and auspicious at the same time, some of which are the Banyan tree, Neem tree, etc.

The Banyan tree can be primarily found in different parts of the country and is considered the national tree of India. Its leaves are used as plates for serving food during festivals, social, and other auspicious occasions. Every household is familiar with the neem tree, whose parts are used for different purposes. Neem leaves make fertiliser for plants and enrich the soil. According to the study of botany, a tree is classified as a perennial plant with leaves, branches, and stems stretching out. The Neem and Tulsi leaves are precious for those who suffer from health issues like cold, cough, and fever. Its leaves make essential oils that serve medicinal uses and help treat insomnia and indigestion.

Some trees like rosemary and sandalwood are used for making beauty products and cosmetics. They are suitable for skincare, give glowing skin, and make hair look flawless. Trees are known for maintaining balance in our ecosystem and making our environment cool. Cutting down too many trees can heat the atmosphere, increase air pollution levels, and make breathing difficult. We need trees for the survival of our species. They provide us with shade and shelter during hot summers. The leaves absorb sunlight and carbon dioxide through a process called photosynthesis, and in exchange, they produce more oxygen. There are many ways to classify trees, but the two common ways are through biological classification.

Types Of Trees

The main types of trees are:

1. Deciduous Trees –  These shed leaves seasonally and is known for their unique leaf pattern arrangements. They are huge flowering plants, and this category includes oaks, maples, etc.

2. Evergreen Trees –  Their leaves don’t shed and last year-round. Some examples are Hemlock, Eucalyptus, and Cycads.

3. Gymnosperms –  Trees that don’t yield any flower or fruit are referred to as gymnosperms. Pine, spruce, and fur are the three most popular types.

Benefits Of Trees

If you want to learn about the value of trees, read on to learn of the following benefits:

1. Peace And Happiness 

Trees make a person feel calm and tranquil, relax them and can be used to experience pleasant emotions.

2. Less Runoff 

They reduce runoff by breaking up rainfall and preventing soil erosion.

3. Build Sustainable Communities 

They can help encourage building sustainable lifestyle practices and grow eco-friendly communities. People who plant trees often look towards natural alternatives to meet their life and food requirements.

4. Beautify Spaces 

It’s easy to turn a barren wasteland into a beautiful landscape by planting more trees.

5. Canopy For Wildlife 

Trees provide shelter to wild animals and protect them from the harmful effects of the sun. There are also other uses of trees, such as food for animals.

Your child can learn a lot about trees by reading an essay on the subject. Writing about trees will make their minds curious and encourage them to research. Treating our environment with care and kindness will help restore this planet.

Now that you know enough about trees, you can get to work on the tree essay. Let us know how it goes in the comments below.

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Essay on Trees

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Trees, the majestic sentinels of our planet, are not merely passive fixtures in our landscapes but active participants in maintaining the ecological balance essential for life on Earth. Their importance spans from local to global scales, influencing climatic conditions, supporting biodiversity, and providing numerous benefits to human societies. This essay explores the multifaceted roles trees play in environmental sustenance, economic stability, and human well-being, underscoring why their preservation is imperative for our future.

The Ecological Significance of Trees

Trees are often referred to as the “lungs of the planet” because of their ability to absorb carbon dioxide (CO2) during photosynthesis, releasing oxygen back into the atmosphere. This exchange is fundamental to life, making trees a cornerstone in combating climate change. By sequestering carbon, trees act as a buffer against global warming, storing carbon that would otherwise contribute to atmospheric CO2 levels.

Beyond carbon sequestration, trees play a critical role in water cycles. They absorb rainfall and release water vapor into the atmosphere through transpiration, contributing to cloud formation and precipitation. This process is essential for maintaining local and regional water cycles and ensuring water availability for agriculture, wildlife, and human consumption.

Trees also combat soil erosion. Their root systems hold soil in place, reducing runoff and sedimentation during heavy rains. This not only preserves soil fertility but also prevents downstream flooding and the degradation of aquatic ecosystems.

Biodiversity Havens

Forests and wooded areas are vibrant ecosystems teeming with life. Trees provide habitat, food, and protection for a myriad of species, from the forest canopy to the undergrowth. The diversity of tree species in an area directly correlates with the overall biodiversity, supporting complex ecosystems that include insects, birds, mammals, and understorey plants.

These ecosystems are not just crucial for wildlife; they are vital for human societies too. Biodiverse systems contribute to resilience against pests and diseases, support pollination for crops, and maintain genetic resources that are key to agricultural and medicinal innovation.

Economic and Social Benefits

The economic benefits of trees extend beyond timber and non-timber forest products. Trees contribute significantly to the economy through ecosystem services such as air and water purification, climate regulation, and soil conservation. Urban trees, in particular, increase property values, reduce energy costs by providing shade, and contribute to social well-being by improving mental health and reducing stress.

In many cultures, trees hold spiritual and cultural significance, serving as symbols of life, growth, and connection to nature. Community spaces under the shade of large trees are often sites for gatherings, rituals, and celebrations, highlighting the intrinsic value trees have in human life and culture.

Trees offer numerous benefits to both the environment and human society. These benefits span ecological, economic, social, and health aspects, making trees invaluable to our planet. Here are some of the key benefits of trees:

• Air Quality Improvement: Trees absorb carbon dioxide (CO2) and release oxygen through the process of photosynthesis, helping to mitigate climate change and improve air quality by reducing greenhouse gas levels and providing oxygen for humans and wildlife.
• Climate Regulation: Trees play a crucial role in regulating local and global climates. They provide shade, reducing urban heat islands, and release water vapor through transpiration, which cools the air and helps maintain balanced temperature and humidity.
• Biodiversity Support: Trees provide habitat and food sources for various wildlife species. Forests, in particular, are home to numerous plant and animal species, contributing to biodiversity conservation.
• Soil Stabilization: Tree roots help prevent soil erosion by anchoring the soil and reducing runoff during heavy rains. They also improve soil health by increasing microbial activity and nutrient cycling.
• Water Quality Enhancement: Trees act as natural filters, reducing pollution by capturing and breaking down pollutants from rainwater and improving the quality of water in rivers, lakes, and aquifers.
• Energy Savings: Properly placed trees can provide shade during hot months, reducing the need for air conditioning and lowering energy bills. In colder seasons, they can serve as windbreaks, reducing heating costs.
• Aesthetic and Recreational Value: Trees enhance the beauty of landscapes and provide spaces for relaxation, recreation, and outdoor activities in parks, gardens, and natural areas.
• Economic Benefits: Trees have economic value in terms of timber production, non-timber forest products, and the creation of green jobs in the forestry and landscaping industries.
• Noise Reduction: Trees can absorb and deflect sound, reducing noise pollution in urban areas and along highways, which can improve overall quality of life.
• Health and Well-being: Exposure to green spaces with trees has been linked to improved mental health, reduced stress, and enhanced overall well-being. Trees contribute to a sense of tranquility and connection with nature.
• Carbon Sequestration: Trees are essential in the fight against climate change as they capture and store carbon dioxide from the atmosphere, thus helping to mitigate the effects of global warming.
• Food Production: Fruit and nut trees provide a valuable source of food for humans and wildlife, contributing to food security and biodiversity.
• Medicinal and Herbal Resources: Some tree species have medicinal properties and are used in traditional and modern medicine for various treatments.
• Cultural and Spiritual Significance: Many cultures and religions have deep spiritual connections to trees, considering them sacred or symbolizing various virtues and values.
• Wildlife Observation: Trees offer opportunities for birdwatching and wildlife observation, allowing people to connect with and appreciate the natural world.

Trees and Urban Environments

In urban areas, trees play a crucial role in improving environmental quality and human health. They filter air pollutants, mitigate urban heat island effects, and provide green spaces for recreation. Urban forests and street trees contribute to the aesthetic value of cities, improve the quality of life for residents, and support urban wildlife.

The strategic planting of trees in cities can reduce energy consumption by providing natural cooling, which, in turn, decreases the reliance on air conditioning. This not only conserves energy but also reduces greenhouse gas emissions associated with electricity production.

Challenges and Conservation Efforts

Despite their immense value, trees and forests face unprecedented threats from deforestation, land-use change, and climate change. Deforestation, driven by agriculture, logging, and urban expansion, not only reduces biodiversity but also contributes to the carbon emissions that exacerbate climate change.

Conservation efforts are critical in reversing the trend of habitat loss and degradation. Reforestation and afforestation projects, sustainable forest management practices, and legal frameworks aimed at protecting existing forests are essential measures. Public awareness and community involvement in tree planting and conservation initiatives play a pivotal role in ensuring the survival and growth of trees for future generations.

The Path Forward

The protection and expansion of our global tree cover are among the most effective strategies for addressing climate change, biodiversity loss, and sustainable development challenges. It requires coordinated efforts across local, national, and international levels, integrating conservation into economic and development planning.

Educational initiatives that raise awareness about the importance of trees and forests are crucial in fostering a culture of conservation. By instilling a sense of responsibility and stewardship in young minds, we can ensure a sustainable relationship with our planet’s invaluable tree resources.

In conclusion, Trees are indispensable to our planet’s health and well-being. Their wide-ranging benefits underscore the necessity of preserving and expanding our forests. As we face the challenges of climate change and environmental degradation, the role of trees in maintaining ecological balance, supporting biodiversity, and providing economic and social benefits cannot be overstated. By championing the cause of trees and forests, we not only safeguard our environment but also secure a healthier, more sustainable future for all life on Earth. The protection of trees is not just an environmental imperative but a moral one, calling on us to act with foresight and compassion for the world we inhabit and pass on to future generations.

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Importance of Trees Essay in English for Students and Children

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Importance of Trees Essay: Trees play a vital role in our environment. They help purify the air we breathe, filter the water we drink, and provide habitat for countless species of plants and animals. They also play an important role in mitigating climate change by sequestering carbon dioxide from the atmosphere.

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Target Exam ---

Trees are necessary for our survival. They provide us with the oxygen we need to breathe, the food we need to eat, and the materials we need to build our homes and furniture. They also help to regulate the climate, protect the soil, and provide homes for wildlife.

Long and Short Importance of Trees Essay in Our Life

Here are long and short essay on Trees in our Life to help you with the topic in your exam. After reading this Essay on tree gives you Importance of Trees in our Life essay you will know the importance of trees in our life and how they help us by providing oxygen in exchange of other harmful or unwanted gases, how trees are important for providing nourishment and shelter to the planet etc.

Trees yield fruits and medicine, contributing to economic growth through exports. They offer wood, paper, and natural cooling in summer, cutting AC bills and preserving the environment.

Trees bear fruits and medicinal products, which are exported to various countries, contributing to economic growth. Growing and selling trees’ products is a source of livelihood for many. Trees also supply wood and paper and serve as natural cooling agents in summer, reducing energy bills and maintaining a natural environment.

Short Essay on Importance of Trees (200 words)

Importance of Trees Essay: Trees are extremely important for us. It is because of plants and trees that we are able to survive on this planet. Trees exhale the life-giving oxygen without which it will not possible for the human beings or other species to live. However, this is not the only reason why trees are important for us. They have a lot to offer to the environment as well as the living beings. Apart from giving oxygen, trees also absorb various harmful gases from the environment thereby reducing the effect of global warming.

Trees also provide us food and shelter. Many trees bear the fruits that serve as food for birds and animals. Human beings also relish various fruits such as mango, apple and banana to name a few. The leaves, roots and bark of trees are used to prepare medicines. Trees also provide shelter to animals and humans. Forests filled with huge, dense trees serve as habitat for wild animals and contribute towards rich biodiversity. Wood and other material extracted from trees is used to craft several things that are essential for a comfortable living.

Trees also make the environment calm and peaceful. They help people meet and socialize. Parks with beautiful green trees and plants are a favourite among small kids and elderly people. They often gather here to indulge in different outdoor activities.

We must save trees and plant more of them to keep our environment clean and promote a healthier and happier life.

Importance of Trees Essay 300 Words

Trees are an essential part of the environment. They make the environment beautiful and fit for the survival of various species of fauna. Life on Earth would not be possible without trees. They are important to us in many ways. It would not be wrong to say that trees give us life.

• Trees Give Us Oxygen

One of the prerequisites for the survival of human beings is oxygen and this is made available by trees. Trees inhale carbon dioxide and exhale oxygen. The more trees we plant the more oxygen we get. This is the reason why going for morning walk in a park full of green trees and plants helps rejuvenate our senses and makes us feel fresh.

• Trees Absorb Harmful Gases

Trees do not only inhale carbon dioxide but also absorb other harmful gases such as carbon monoxide and sulphur dioxide from the environment. Various other pollutants are also absorbed by the trees. This process purifies air and keeps the atmosphere clean. The growing pollution in the atmosphere can be undermined by planting more and more trees.

• Trees Provide Food

Trees bear fruits that quench our hunger. Different trees bear different types of fruits rich in various micronutrients. Fruits are eaten raw and fresh and even in their dried forms. Other parts of the trees such as leaves, roots and bark are also used to prepare different food items. The leaves, fruits and bark of trees are also used to prepare herbal medicines that help cure various illnesses.

• Trees Provide Shelter

Trees provide shade and serve as shelter for people as well as animals. They offer a cool place to sit on a hot summer day. Trees also provide wood that is used to build houses and furniture.

Trees are life saviours. We can enjoy good quality life only when we have abundance of trees around. We should avoid cutting trees and plant more of them. We must also encourage those around us to plant trees.

Importance of Trees Essay in our Life 400 Words

Trees make our environment beautiful and soulful. They help build a healthy community life. A neighbourhood with green and shady trees exudes positive energy and is happier compared to one that lacks greenery.

Trees Provide Peaceful Environment

Trees have the power to calm our senses and bring positivity. We travel far and wide to spend our holidays amid nature. Lush green trees, high mountains and gushing streams make for a serene environment that rejuvenates us. While we cannot get the same ambience in the cities, however we can certainly plant more trees to make our surroundings peaceful and beautiful.

Areas that are greener offer a more peaceful environment. The air here is fresher and the atmosphere is cooler. People residing in such areas experience less stress and are happier which forms the basis of a healthy community life.

A Meeting Ground for Children and Elderly

Essay on Tree: A park with lush trees and beautiful plants brings the neighbourhood people closer. Neighbourhoods that have beautiful parks see people gathering around during the early morning and evening hours during the summer months and during afternoon time on the cold winter days. These parks serve as a meeting ground, especially for kids and elderly people. It helps them make new acquaintances and socialize.

Place to Impart Education

During the ancient times, children were imparted education under the tree. Many under tree schools were opened in different areas. An entire classroom was set under the tree and students sat there to take lessons from their teacher. Even today, many rural areas run such schools. These schools offer education at nominal charges and sometimes even free of cost.

Trees Provide Shelter to Travellers

Trees provide shade to the travellers. They offer a cool place to sit and relax. Taking nap under cool, shady tree helps one re-energize. Trees often serve as a meeting ground for travellers headed in the same direction.

Trees – A Respite for Farmers and Labourers

Farmers, labourers and other workers who toil hard under the sun usually sit under the tree to have their lunch. They also chit-chat with their fellow workers and strengthen their bond with them as they sit in the shade of the tree.

So, we see trees render positivity and help people socialize. Beautiful parks with array of green trees and plants serve as a place to meet new people. They are also a great place to indulge in outdoor activities with our near and dear ones and deepen our connection with them.

Importance of Trees Essay in our Life 500 Words

Trees: Essential for Balancing the Ecological System

Essay on Tree: Trees play a significant role in balancing and maintaining the ecological system of Earth. Green trees and plants fill the atmosphere with oxygen, purify air, prevent soil erosion, support wildlife, and aid in climate control. Here is a brief look at how trees help in all these processes to keep the ecological system intact.

Purification of Air

Our atmosphere is filled with all kinds of harmful gases including carbon dioxide, carbon monoxide and sulphur dioxide to name a few. The increasing number of vehicles on the road and the growing number of factories around the world are increasing the level of these harmful gases in the atmosphere. Trees inhale carbon dioxide and exhale the pure and fresh oxygen that we human beings require for our survival. Trees also absorb other harmful gases to keep our environment clean. This is the reason why areas with greater number of trees are less polluted.

We must plant trees to purify and clean our environment.

Promote Biodiversity

Forests serve as a habitat for the wild life. Trees give shelter to numerous species of birds and animals. Thus, they promote biodiversity. Deforestation, which is one of the main concerns these days, has led to loss of biodiversity. Animals and birds are losing their habitats and finding it hard to survive. Researchers claim that, further loss of biodiversity can impact the ecological system adversely. This is because animals and plants are dependent on each other for the fulfilment of many of their needs. Planting more trees and avoiding deforestation can help boost biodiversity and maintain the ecological balance.

Prevent Soil Erosion

Heavy rains cause soil erosion that disrupts life of people living in effected areas. The roots of trees hold the soil and keep it from eroding as it rains. Big trees absorb substantial amount of water and reduce the chances of sediment deposits in the rivers. Soil erosion causes several problems such as increased level of water in rivers and streams. This harms the marine life and often even results in flood. By preventing soil erosion, trees help in maintaining the ecological balance.

Conserve Energy

Areas surrounded by trees are cooler. People living in such areas do not require keeping their air conditioners on constantly. This helps in the conservation of energy. This is also a good way to reduce the emission of harmful gases and pollutants.

Balance the Water Cycle

Trees help in balancing the water level in the atmosphere. Big trees release a good amount of water into the atmosphere. This process replenishes the clouds and results in rain. Forests around the world play a major role in the water cycle and help in maintaining the ecological system. Planting trees is the way to balance the water cycle which is important for keeping the environment intact. Deforestation, on the other hand, disrupts the water cycle which in turn has negative repercussions such as dryer soil, loss of crops, etc.

Thus, trees are extremely important for the environment. They help in maintaining the ecological system and make living possible on Earth. The more trees we plant the better environment we create for ourselves.

Importance of Trees Essay 600 Words

Trees are extremely important for us. They give us oxygen and keep our environment clean by absorbing various harmful gases and pollutants from the atmosphere. We can breathe freely and live a healthy life because of the presence of trees around. However, even as trees are so important, humans are cutting trees ruthlessly without realizing that cutting trees means putting our lives in danger.

Deforestation – The Bitter Truth

Humans are cutting forests rapidly in the name of development and urbanization. Many forests and green patches around the world have been cut in the last few decades to make place for the growing human population and to fulfil their ever increasing material demands.

More and more people, these days, are moving from rural areas to urban cities. In order to accommodate them, the residential areas in the cities are being expanded and this is being done at the cost of trees. Trees are being cut and concrete jungles are being constructed in their place. Factories, offices and residential societies are being established at places that were once surrounded by beautiful green trees.

Trees are also being cut rapidly as the requirement for wood and other materials extracted from them is increasing by the day. Houses, tools, furniture, paper, medicines and a whole lot of other things are crafted from wood. While all these things are essential for living, we must not forget that our first and foremost need for survival on Earth is oxygen. If we continue to cut forests at this rate, the required supply of oxygen will dip and it would become difficult to live on this planet.

Deforestation also means loss of habitat for wild animals. Several species of animals have gone extinct from the face of Earth in the past and numerous others are on the verge of extinction. One of the main reasons for this is deforestation. This has also increased contact between humans and wild animals and the two stay in constant fear of each other. Other impacts of deforestation include disruption of water cycle, soil erosion and increasing pollution and heat. These are all equally bad for human beings as well as animals.

Plant Trees – Promote Life

Essay on Tree: Human beings have grown accustomed to a comfortable life. Many of the things we get from trees have become a necessity for us so much so that we have become deaf and blind to the repercussions of deforestation and the forthcoming danger.

While cutting trees has become necessary to fulfil many of our essential demands it must be done in moderation. Besides, to balance the act we must take it as our responsibility to plant more and more trees. Each one of us must plant trees regularly and also take care of them. Every neighbourhood should conduct regular tree plantation activity.

Students must be given lessons on the importance of saving and planting trees. School management must also conduct regular tree plantation activity and every student must be encouraged to take part in it. The more trees we will plant the better environment we will create for ourselves and the future generations. Likewise, regular activities must also be carried out to water the trees and boost their growth. This will help them bloom faster.

The importance of trees has been stressed upon time and again. It is time we should realize that cutting trees means a threat to our own lives. Deforestation must be stopped to sustain life on Earth. The loss of trees must be replenished by planting many more of them. Every individual should plant trees and contribute towards keeping the environment clean.

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Essay on Tree FAQs

How do you write a tree essay.

Start with an introduction, describe tree benefits, and conclude with its significance.

What are the 10 importance of trees?

Trees provide oxygen, shelter, food, shade, and more. See an essay for details.

What is trees in 10 lines?

Trees offer oxygen, homes for animals, and materials for humans, supporting our environment.

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Essay on Importance of Trees

Students are often asked to write an essay on Importance of Trees in their schools and colleges. And if you’re also looking for the same, we have created 100-word, 250-word, and 500-word essays on the topic.

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100 Words Essay on Importance of Trees

Introduction.

Trees are essential to life. They provide oxygen, store carbon, and are home to numerous creatures.

Life Givers

Trees create oxygen, a necessity for humans and animals. Without trees, life would not exist.

Climate Protectors

By absorbing carbon dioxide, trees help control climate change, making Earth habitable.

Many species live in trees. They provide food and shelter, maintaining biodiversity.

Trees are vital for our survival and for the planet’s health. Let’s protect and plant more trees.

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250 Words Essay on Importance of Trees

The life-giving role of trees.

Trees, the silent sentinels of nature, provide far more than aesthetic appeal. They are vital to our existence, playing a critical role in maintaining the balance of our ecosystem.

Climate Moderation

Trees act as natural climate moderators. They absorb carbon dioxide, a greenhouse gas, and release oxygen, contributing to the reduction of global warming. A mature tree can absorb approximately 48 pounds of carbon dioxide per year, emphasizing the importance of tree conservation in combating climate change.

Biodiversity Conservation

Trees are habitats for a multitude of species, promoting biodiversity. They provide food, shelter, and breeding grounds for various organisms. Loss of trees can lead to a decrease in biodiversity, disrupting the balance of ecosystems.

Water Cycle Regulation

Trees play a crucial role in the water cycle. They absorb rainwater and reduce runoff, preventing soil erosion and flooding. Their transpiration process also contributes to cloud formation, influencing rainfall patterns.

Human Health and Well-being

Trees have a profound impact on human health and well-being. They purify the air by filtering harmful pollutants, contributing to respiratory health. Moreover, green spaces have been linked to improved mental health, reducing stress and promoting relaxation.

The Economic Value of Trees

Trees contribute to the economy through timber production, non-timber forest products, and tourism. They also increase property values, demonstrating the economic benefits of tree conservation.

In conclusion, trees are integral to our survival and prosperity. The importance of trees cannot be overstated. Their conservation should be a priority, ensuring a sustainable future for all species.

500 Words Essay on Importance of Trees

The quintessential role of trees: an ecological perspective.

Trees, the longest living organisms on Earth, are more than just a part of our natural landscape. They are integral components of our ecosystem, contributing significantly to the health and wellbeing of our planet. They serve as the green lungs of Mother Earth, offering myriad benefits that are vital for our survival and prosperity.

Trees: The Guardians of Biodiversity

Trees provide a habitat for a plethora of species, including birds, insects, and mammals. They act as a refuge, breeding ground, and source of food for these organisms. Without trees, many of these species would struggle to survive, leading to a disruption in the delicate balance of biodiversity. This balance is essential for the health of our ecosystems, as each species plays a unique role in maintaining the overall harmony of the environment.

A Natural Solution to Climate Change

Trees are potent tools in the fight against climate change. They absorb carbon dioxide, a primary greenhouse gas, and release oxygen, thereby reducing the overall carbon dioxide levels in the atmosphere. This process, known as carbon sequestration, is a natural way of mitigating the impacts of climate change. Moreover, trees help to cool the environment by providing shade and releasing water vapor into the air, a process known as transpiration.

Contributors to Human Health and Wellbeing

Trees contribute significantly to human health and wellbeing. They act as natural filters, removing harmful pollutants from the air and providing us with clean, breathable air. Studies have shown that exposure to green spaces can reduce stress, enhance mood, and improve mental health. Furthermore, trees in urban areas can reduce the heat island effect, leading to cooler temperatures and reduced energy consumption for air conditioning.

Economic Value of Trees

Trees also have considerable economic value. They provide timber, fruits, and other products that contribute to local and global economies. Additionally, trees in urban areas can increase property values, as they enhance the aesthetic appeal of neighborhoods. The tourism industry also benefits from the existence of lush forests and beautiful trees, attracting visitors from around the world.

Conclusion: A Call for Tree Conservation

Despite their immense importance, trees worldwide are under threat due to deforestation, urbanization, and climate change. It is crucial that we recognize the value of trees and take steps to protect and conserve them. This includes implementing sustainable forestry practices, planting more trees, and creating policies that protect existing forests. As we continue to grapple with the effects of climate change and environmental degradation, the role of trees in our lives and their importance in maintaining the health of our planet cannot be overstated.

In conclusion, trees are not just silent spectators but active participants in the preservation of our planet. They stand as a testament to the intricate interplay of life, reminding us of our responsibility to protect and conserve the natural world for generations to come.

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A Review of the Benefits of Nature Experiences: More Than Meets the Eye

Lara s franco, danielle f shanahan, richard a fuller.

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Correspondence: [email protected]

Received 2017 Jun 1; Accepted 2017 Jul 26; Issue date 2017 Aug.

Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license ( http://creativecommons.org/licenses/by/4.0/ ).

Evidence that experiences of nature can benefit people has accumulated rapidly. Yet perhaps because of the domination of the visual sense in humans, most research has focused on the visual aspects of nature experiences. However, humans are multisensory, and it seems likely that many benefits are delivered through the non-visual senses and these are potentially avenues through which a physiological mechanism could occur. Here we review the evidence around these lesser studied sensory pathways—through sound, smell, taste, touch, and three non-sensory pathways. Natural sounds and smells underpin experiences of nature for many people, and this may well be rooted in evolutionary psychology. Tactile experiences of nature, particularly beyond animal petting, are understudied yet potentially fundamentally important. Tastes of nature, through growing and consuming natural foods, have been linked with a range of health and well-being benefits. Beyond the five senses, evidence is emerging for other non-visual pathways for nature experiences to be effective. These include ingestion or inhalation of phytoncides, negative air ions and microbes. We conclude that (i) these non-visual avenues are potentially important for delivering benefits from nature experiences; (ii) the evidence base is relatively weak and often based on correlational studies; and (iii) deeper exploration of these sensory and non-sensory avenues is needed.

Keywords: sensory, nature benefits, nature experience, wellbeing, nature therapy

1. Introduction

Experiences of nature provide people with multiple benefits to health and well-being, yet the mechanisms by which these benefits are delivered are not well understood [ 1 , 2 ]. Interest in nature as a therapeutic resource has ancient foundations. Hippocrates extolled the necessity of “airs, waters, and places”, for physical and mental well-being [ 3 ], and ancient Roman texts suggest that there are health benefits to countryside and greenspaces [ 4 ]. Gardens were prescribed for monasteries in the 1200’s “not only for food, but also for recreation in the open air to aid the recovery of the sick and to preserve health and improve those fatigued by their spiritual studies,” according to the Franciscan Minister General, Bonaventura, in 1260 [ 5 ]. In 1839, the Annual Report of the British Registrar General opined that, “a park in (the) East End would diminish annual deaths by thousands and add several years to the lives of the entire population” [ 4 ]. Overexposure to manmade environments was believed to cause “excessive nervous tension, over-anxiety, hasteful disposition, impatience and irritability” [ 6 ]. An early American illness known as neurasthenia with symptoms of depression, anxiety, insomnia, and migraines, was often cured with nature therapy, known as the “west cure”, where men (including prominent figures such as poet Walt Whitman, painter Thomas Eakins, novelist Own Wister, and US President Theodore Roosevelt) were sent west to ranches to work roping horses on the range [ 7 ]. The cure they suggested was simple: experiences of pleasant rural scenery. This idea has spawned an enormous volume of research on the visual appeal and restorative potential of natural landscapes [ 8 , 9 , 10 ]. However, emphasis is repeatedly placed on experiences of pleasant rural scenery . Perhaps as a result of vision being the dominant human sense, research has focused heavily on the visual benefits of nature experiences potentially at the expense of understanding the non-visual senses, and other pathways such as airborne volatile chemicals and the ingestion of microbiota. Emerging evidence is pointing to the existence of a broad range of sensory and non-sensory pathways for the benefits of nature experiences. Yet the research base isolating sensory experiences of nature beyond vision is sparse. In this paper, we review the state of this evidence so far, and identify some important gaps in our understanding of how nature experiences benefit human health and well-being.

The multi-sensory aspect of nature experiences is crucial because monotony of stimulation can be a source of stress [ 11 ] and multimodal sensory input itself can drive positive mental states such as tranquility [ 12 ]. Indeed, it has been shown that stimulating multiple senses at the same time may possibly lead to additive beneficial effects of nature experiences [ 13 ]. For example, one study found that while a virtual nature environment was able to reduce stress in participants, these participants also felt negatively towards the virtual environment, and expressed a sense of missing the full sensory experience of real nature [ 14 ]. This example highlights the possible shortcomings of assuming visual delivery is the dominant pathway through which nature benefits are delivered.

In this paper, we review the ways in which we experience nature through each of our senses and through several non-sensory pathways. Most of the literature we review focuses on the passive reception of benefits, but it should be recognized that there may be benefits derived from a more active engagement with the environment. More specifically, there may be a difference between passive sensation, and the next step after it of processing to perception.

This paper is intended to be a narrative review of disparate literature designed to provide a reference for wider reading rather than to provide a systematic review of the evidence. As such, no systematic search or synthesis has been attempted and instead, a number of search terms were used and anything considered relevant to senses and nature benefits was included. Multiple study designs were included, as well as research on animals in addition to humans. Some search term examples, for sound, included “sound”, “noise”, “nature benefit”, “wellness”, “health”, “wellbeing”, with similar searches for the other senses. When relevant articles were found, a snowballing method was utilized, searching their references for further relevant articles. In some instances where very few results were found, we included preference studies as well as correlational studies where the effects of possible confounding variables could not be assessed.

We define nature in a broad sense as “the phenomena of the physical world collectively, including plants, animals, the landscape, and other features and products of the earth, as opposed to humans or human creations” [ 15 ]. We consider nature to include phenomena as varied as landscapes, microorganisms, and pets, and we also include nature simulations. We consider health as “the state of being free from illness or injury”, and as a statement about one’s mental or physical condition [ 15 ]. Finally, we define wellbeing as “the state of being comfortable, healthy, or happy” [ 15 ], and including self-acceptance, personal growth, purpose in life, environmental mastery, autonomy, and positive relations with others [ 16 ]. It further includes the important domains of mental well-being, social well-being, physical well-being, spiritual well-being, activities and functioning, and personal circumstances [ 17 ]. Therefore wellbeing is a very broad category encompassing concepts as varied as “freedom from noise” and “memory recall”.

Senses can be thought about in two broad ways: as passive reception and as active searching. Our paper has not differentiated between the two, but focuses more on the passive sense as there seems to be more literature here. It would also be possible to look at perception (that is a further step away from sensing and includes some processing). Much of the literature does not seem to make these distinctions and this may be an area of possible future research.

Viewing nature has been repeatedly demonstrated to provide a range of benefits for human health and well-being [ 18 ]. Benefits include reduced anxiety [ 19 ], reduced stress [ 20 ], shorter hospital stays [ 21 ], lower heart rate [ 22 ], and increased directed attention [ 23 ]. The duration of these benefits has not been investigated and is an avenue of possible future research. Hospital patients recovering from surgery showed greater positive affect, received fewer negative notes from nurses (where nurses recorded the patient’s mood and attitude) and spent less time in hospital if their room overlooked trees instead of a brick wall [ 21 ]. In another study, pictures of art depicting nature (trees, greenery, flowers, and water) were rated positively by hospital patients, while abstract art increased anxiety, suggesting that nature content, itself, was important [ 24 ].

It remains unclear precisely which elements of a view of nature are beneficial, hampering the design of natural therapy interventions or of urban greenspaces themselves. Three quarters of studies only make a coarse division between “urban” and “nature” when studying the beneficial effects of nature views [ 18 ], and so we remain unsure which visual elements of landscapes are responsible for the benefits. It may be that only a combination of elements in a coherent scene confers benefits, or it may be that individual elements alone are sufficient. For example, the colours of nature could be important. Blues and greens, which predominate in nature scenes are low-arousal, low-anxiety, and highly preferred colours [ 25 , 26 , 27 ], while the gray colours of urban scenes seem to result in feelings of aggression [ 28 ] and dominance [ 25 ].

There are other possible visual cues that could make nature environments restorative: the lack of straight lines, the shape of the vegetation, and visual variety in the scenery. A study by Berman et al. [ 29 ] found that naturalness was associated with density of contrast changes, density of straight lines, average color saturation, and average hue diversity. Another study found that curves and hue diversity had effects on preference [ 30 ]. Fractals, which are found in many natural images, may also have some role in aesthetic preference [ 31 ].

While there is plentiful literature showing the health and well-being benefits of visual nature, it remains uncertain which elements of this visual experience contribute to the benefits. In a review of comparisons between moderately realistic computer animations and the corresponding real environments it was suggested that the former do not generate the same self-reported cognitive and affective responses as the latter [ 32 ], implying that while the visual aspect of the environment does drive some benefits, it is far from the only likely mechanism.

Based on the number and relevance of literature found, hearing appears to be the second most-studied of the human senses. Hearing is the perception of acoustic waves that provide us with information about the environment. Our auditory systems are evolved to be most sensitive to sounds that are most important to our survival and reproduction [ 33 ]. Natural sounds, usually considered the most complex and informational of sound types, can provide information on species, season, and temporality [ 34 ], and it is likely that we are attuned to such cues. Indeed a component of attention restoration theory is that restorative environments provide us with information [ 35 ], and it thus seems plausible that the rich information content of nature sounds contributes to the restorativeness of natural landscapes. Sounds are also a component of place attachment [ 36 ] and are felt as a link to the environment [ 36 , 37 , 38 ], both of which could be associated with positive feelings about one’s environment [ 39 ].

It has repeatedly been shown that the sounds of nature such as wind, water, and animals, are preferred over anthropogenic sounds such as traffic, recreational noise, and industrial noise [ 40 , 41 , 42 , 43 , 44 , 45 ]. With respect to perceived restorativeness, rural soundscapes and botanical gardens were preferred over urban park soundscapes, which were preferred over urban soundscapes [ 46 ]. Preferred environments have been found to be correlated with restorative potential [ 47 , 48 ], so the existence of positive preferences for nature sounds implies, though does not demonstrate, that they might themselves be restorative. Indeed, bird sounds have been found to increase recovery of skin conductance level, a measure of stress [ 49 ], and visitors to a local river cited the sound of water as a reason to visit a local river for its relaxing effects [ 50 ].

Nature sounds have been used therapeutically to relieve stress [ 49 , 51 , 52 ], and perceived restoration and attention recovery have shown positive reactions to birdsong [ 53 ]. A virtual reality forest including sound was found to improve stress recovery more than the same forest without sound, implying that the sympathetic nervous system shows increased recovery with nature sounds [ 54 ]. A zoo exhibit including rainforest sounds was rated as more pleasant than the same exhibit without sounds [ 55 ], and natural sounds have also been found to decrease self-reported anxiety and agitation [ 56 ].

Images of cities receive higher ratings of perceived pleasure when paired with nature sounds, especially water, while urban sounds were found to decrease the ratings of natural images [ 42 ]. Ratings were especially high for nature image and sound combinations, as “apparently sounds provide a specific kind of information over and above the visual which helps enhance and emphasize the different components of the environment” [ 42 ]. Sound combined with 3D images increased realism and preference ratings when it was congruent [ 57 ]. Appraisals of places depend on the sounds heard there [ 58 , 59 ], highlighting the importance of sound. Sounds have been found to affect the perceived realism of simulated environments [ 60 ], as well as their perceived naturalness, solitude, and freedom [ 45 , 61 , 62 , 63 ]. At low levels, nature sounds were found to decrease perceived crowding and increase interpersonal encounter tolerance [ 64 ], while fountain and bird sounds were found to decrease perceived loudness of traffic and enhance soundscape pleasantness and eventfulness [ 65 ]. Indeed, the absence of human-made sounds allowing for the perception of nature sounds is considered to be very pleasurable [ 66 ].

4.1. When Sound Becomes Noise

Noise pollution has become an increasing public complaint in the last decade [ 67 ], and some 80 million Europeans live with unacceptably high urban noise levels [ 68 ]. Chronic noise contributes to stress, annoyance, cardiovascular problems, sleep disturbance, and decreased task performance [ 69 , 70 , 71 ]. It has both psychological and physical effects ranging from elevated blood pressure, poor sustained attention, and memory problems to sleep disturbances, increased risk of myocardial infarction, annoyance, and learned helplessness [ 72 , 73 , 74 , 75 , 76 , 77 , 78 ]. These effects can occur below our level of awareness [ 79 ].

Since noise negatively affects our health and wellbeing, the respite from it found in nature is potentially an important benefit. Seeking freedom from noise is likely to be a driver for many to seek out natural soundscapes and recreational nature experiences [ 80 ]. “Natural quiet”, that is natural sounds without anthropogenic noise, is considered by the US Congress and National Park Service as an important resource to be protected [ 81 , 82 , 83 ]. Vegetation itself has a significant dampening effect on noise, and this is a well-reviewed ecosystem service [ 84 ].

Quiet and natural sounds increase the quality of visitors’ experience in parks [ 72 ], and escaping noise to enjoy natural sounds is an important reason for visiting parks [ 85 ]. Supporting this, 91% of Americans cite enjoyment of quiet and natural sounds as a reason to visit national parks [ 86 ], and 72% believe that a reason to protect national parks is to preserve the natural quiet and nature sounds [ 87 ], suggesting they consider them to be of some benefit. Sounds considered most pleasing include water, wind, birdsong, and bird chatter [ 45 ], and these sounds were found to be pleasing to campers and mountaineers [ 88 ]. Visitors to natural parks are sensitive even to low levels of anthropogenic noise, which significantly detracts from their enjoyment [ 79 ].

4.2. Warnings in Silence

If quiet is so important, why is silence in an urban environment not a good thing the same way it is in a natural environment? While “peace and quiet”, as described in the previous section, is frequently sought out by humans looking for restoration, auditory deprivation in a laboratory setting increases anxiety [ 89 ], and total silence in a natural environment might well have negative connotations. In the earlier example of a virtual reality forest which, with sound was found to increase stress recovery, the same forest without sound was found to induce apprehension and a fear of threat [ 54 ]. This may be because silence in nature can indicate predator presence or depauperate biodiversity. Indeed, participants in the Annerstedt et al. [ 54 ] study indicated that they felt a predator was about to reveal itself in the silent virtual forest.

It is possible that over the course of our evolution, we came to identify silence with the response of most animals to a predator’s presence. It has been suggested that humans evolved humming as a way to signal safety during quiet times so there would be no silence [ 90 ]. Other animals perceive and use silence as a danger warning. Many insects, for example, become silent when they detect a predator [ 91 ], as do tungara frogs, Engystomops pustulosus , which use the silence of neighbours as an alarm cue to silence their own singing [ 92 ]. In fact, animals frequently detect predators “vicariously” through the alarm response of others [ 93 , 94 , 95 ], remaining in “adaptive silence” [ 96 ].

Together this suggests that to animals (including humans), a silent landscape would generally prove disturbing or unnerving [ 42 ]. In the urban environment, we are often faced either with situations that have an overabundance of anthrophony (human-generated noise), or an absence of any noise at all (e.g., a deserted alleyway late at night). Both situations are devoid of the reassuring animal noises that can be identified with a safe (i.e., predator-free) and abundant (i.e., prey-full) environment. Therefore, in addition to nature sounds providing the positive benefits described above, a lack of nature sounds could contribute to negative outcomes such as apprehension and anxiety.

Smell is one of our weakest senses, yet the world around us emits all kinds of smells. Smells are everywhere, and this is true of both urban and natural environments. The main difference between these two environments is the abundance of anthropogenic smells in urban environments, and the lack of them in natural environments. Nature abounds in smells from flowers, trees, shrubs, grasses, animals, rotting matter, and insects. How these smells affect our health and wellbeing is an interesting, but relatively poorly studied question.

Smell can have profound effects on our mood, behavior, and cognition. Many natural odors are commonly found to be pleasant. For example, thoughts about the odors of flowers, cut grass, and damp earth, might evoke feelings of pleasure. However, there are also odors associated with information, such as the distaste we feel at the odor of rotting meat signaling its unpalatability. Some of the benefits of natural odors are the pleasant affective states they induce, as well as the warnings they have about potential toxicity. The odors of summer air (leaf alcohol) and bees wax have been shown experimentally to be associated with the emotion of happiness in participants [ 97 ], and in an experiment in a fragrant garden, “natural odors derived from blooming plants increased calmness, alertness, and mood” [ 98 ]. The natural odors of lavender and spiced apple have been shown to alter brain activity, and thus affect cognition as measured by EEG beta and theta waves, which show changes similar to those seen during cognitive tasks involving internal verbalization [ 99 ]. Our preferences for odors seem to be associated with the value we place on the objects associated with that odor [ 100 ], so smells that remind us of the outdoors can trigger any of the positive feelings we have about nature. Nature smells can thus function as a kind of trigger or symbol for nature in general and might deliver nature benefits by proxy. So while nature smells can have direct nature benefits, they can also have indirect nature benefits.

As in the case of rotten meat and the disgust response to the smell, smells can provide us with useful information about the environment, or specific resources or organisms within it. In a study on humans, it was found that men and women could identify whether individuals were happy or fearful based on odor pads used to collect their sweat [ 101 ]. Natural odors from plants and animals such as floral fragrance and musk, are indicative of metabolism and physiological function [ 102 ], so smells can tell us about the state of possible food.

One of the ways olfactory molecules can affect us is the link between the sense of smell and the limbic (emotional) system [ 103 , 104 ]. Emotions and odors are connected [ 105 , 106 , 107 ], and olfactory disorders can manifest as depressive episodes [ 107 ]. The olfactory system is also connected to hunger (hypothalamus), and memories (hippocampus) [ 108 , 109 ], and affects mood [ 110 , 111 , 112 ], cognition [ 99 , 113 ], and behavior [ 114 , 115 ]. This suggests a clear potential avenue through which nature benefits could be received via smell, yet there are very few studies on the role of smell in delivering health and well-being benefits of nature experiences.

Given the paucity of work on the link between smell and benefits from nature experiences, some results from studies not directly focused on natural smells suggest some intriguing possibilities. In a study on attraction and social perception, it was found that perfume (a pleasant scent) had an effect on perceived attractiveness and perception of the user’s traits [ 116 ]. It has also been found that odors can cause a change in a person’s liking rating of a face in a photograph [ 117 ]. Helping behaviors (such as picking up a dropped pen) increase during exposure to pleasant odors such as cookies or coffee, as does positive mood, which may have a mediating effect [ 118 ]. Individuals exposed to a floral and a lemon fragrance performed better on an anagram word task, as well as being more willing to volunteer for a task afterwards [ 119 ]. Because these effects also occurred when a small gift was given, it is theorized that these effects, too, are mediated by positive affect.

Exposure to both muguet (a relaxing fragrance) and peppermint (an alerting fragrance) increased signal detection by participants in a 40 min visual sustained attention task, indicating enhanced vigilance performance [ 120 ]. In the context of learning, it has been found that subjects exposed to the odors of jasmine or perfume while learning recalled a list of words better when they were exposed to the same scent from when they learned the words the first time, indicating odor as a possible memory eliciter [ 121 ].

These results from some artificial and nature-mimicking odors implies that there are well-being benefits from smell, and this area of nature experiences seems likely to repay further investigation.

Essential Oils

Plant essential oils have long been thought to have physiological and psychological effects according to folk belief [ 112 ], and fragrances have been used for their effects on health and mood [ 122 ]. Essential oils are typically obtained by distillation from plant material and have the characteristic odor of the original tissue. There is much anecdotal evidence that aroma molecules affect human behavior and physiology, as well as memory activation and mood [ 123 , 124 ], yet experimental evidence is sparse and often equivocal. Essential oils have been shown to decrease depression, anxiety, stress, and blood pressure [ 125 , 126 , 127 ], and different oils have been found to have different effects [ 128 , 129 ]. It remains unknown whether the effects of documented and/or claimed for essential oils also occur in situ in places where the sources of the essential oils occur in natural environments.

In humans, a review found that there is some support for using sensory interventions, including aromatherapy, in the treatment of the behavioral symptoms of elderly dementia [ 130 ], and another review found some evidence that aromatherapy lowered blood pressure in patients with hypertension, but suggested there was a need for more studies with adequate controls [ 131 ].

Reviews of the effects of essential oils suggest the evidence so far remains contradictory. For example, Cavanagh and Wilkinson [ 132 ] concluded that there is clinical and scientific evidence supporting the use of lavender oil for traditional uses such as calming and anti-depressant effects, despite methodological and oil identification issues. However, another review on aromatherapy concluded that it only had mild anti-anxiety properties, with no other effects supported by clinical trials [ 133 ]. A study on aromatherapy use by nurses found that there was not enough empirical evidence (other than for enhancing relaxation) to support its use [ 134 ]. However, a review on studies on older patients with dementia found that essential oils did have an effect on cognitive function and independence of daily activities [ 135 ]. It has also been found that essential oils have pro-oxidant effects at the cellular level, with anti-mutagenic effects, and thus presumably anti-carcinogenic effects as well [ 136 ]. It is quite well established that some essential oils have antimicrobial effects, but this is usually tested with topical application, rather than through the volatile element [ 137 ]. It makes sense that essential oils would have biological effects, as they are produced by plants to protect against herbivores and pathogens and to attract pollinators [ 138 ], however, evidence seems to be predominantly anecdotal thus far. Further experiments on clinical benefits are needed, and the controlled nature of studies thus far precludes understanding of whether such benefits can be experienced in everyday life. Nonetheless, the findings indicate an avenue for future research which could make unique contributions to the literature.

Taste is a very specific and close-range sense that tells us about what we put in our mouths. As such, it is mostly applicable to food, which is, of course, crucial to our survival. Therefore, taste is a very fundamental sense that has implications for our overt health and ties us inextricably to nature. Since taste is mostly about food, other factors that surround food, such as methods of food production, have important implications for our well-being. Food comes from nature, from local or international farms, and as such, can represent a link to nature even when we do not directly experience it. It is something we cannot avoid, a constant reminder of our natural roots; no matter how much we urbanize, we always have to import food from nature.

6.1. Enjoyment of Flavours

One way that the sense of taste can contribute to the benefits we receive from nature is through our enjoyment of the flavours in natural foods. Infants were found to respond positively to sugar solutions and negatively to salty and sour flavours [ 139 , 140 ], showing that an emotional response to flavours is present from birth. Links have been found between our emotions and our neuronal responses to the taste (and smell) of food, and there are regulatory mechanisms that produce feelings of satiety and control our intake of food [ 141 , 142 ]. This is important because it regulates our nutrition intake and is thus an important benefit of the natural property of foods. In fact, “taste is unique among sensory systems in its innate association with mechanisms of reward and aversion” [ 142 ]. Specifically, sweet flavours are rewarding, while bitter flavours are aversive [ 142 ]. This is important as it tells us what is safe to eat, as many bitter flavours are indicative of the toxic properties which many plants and insects use to deter attack [ 143 , 144 , 145 , 146 , 147 ]. Carnivores are more sensitive to bitter tastes than herbivores and are also less tolerant of the related toxins in plants [ 148 ]. Therefore one of the benefits of taste is in telling us what foods are healthy and which are toxic.

A study looking at emotional responses to food found that the most common emotions experienced were satisfaction, enjoyment, and desire, while sadness, anger, and jealousy were experienced the least often [ 149 ]. Therefore, taste appears to improve positive affect. It is believed that eating may reduce anxiety and other undesirable emotions [ 150 , 151 ], and this could be a nature benefit of what was once completely natural foods (although now there is “processed” food, most studies use natural foods).

6.2. More Natural Food

Organic food has become the “more natural” alternative for consumers. For instance, among the reasons for purchasing organic foods, consumers cited “sensory and emotional appeal” as the second most important one, and indicated that more natural foods are perceived as tasting and smelling better, as well as making the consumer feel better when eaten, invoking feelings of comfort, safety, and tradition [ 152 ]. Other studies and a review [ 153 ] have also highlighted the importance of better taste in organic food selection [ 154 , 155 , 156 , 157 , 158 , 159 , 160 , 161 , 162 ]. In a sensory analysis using trained panelists, one study found that organic orange juice, though not organic milk, tastes better than conventional orange juice [ 163 ]. One theory suggests that the improved taste could be due to the use of lower yield varieties by organic producers, which tend to taste better [ 164 ]. Organic foods are also preferred for a perceived higher nutritional quality and greater health benefits [ 165 , 166 , 167 ], so contributions to health would be another nature benefit of natural foods. Indeed, a Norwegian study, while correlational, found that those eating a diet high in processed foods had a higher level of anxiety, while those eating a diet with more natural foods had a lower incidence of depression [ 168 ]. Among schizophrenics, it was found that fewer males were consuming acceptable levels of fruit and vegetables [ 169 ]. A link has been theorized in arctic people between a change in diet from traditional (more natural) foods to a Western diet (more processed foods) and a decline in mental health [ 170 ], implying that more natural and traditional foods are better for mental well-being. Natural, unprocessed foods are also better for us physically. “Chronic illnesses and health problems either wholly or partially attributable to [a modern diet] represent by far the most serious threat to public health” [ 171 ]. Fruits and vegetables have high nutritional content, and there is a movement in South Korea to maintain aspects of the traditional diet considered to be healthy, such as high vegetable intake [ 172 ]. The traditional Okinawan diet is well-recognized for its healthy properties, and is much higher in fruits and vegetables than the modern Western diet [ 173 ]. There is concern that our modern diet which depends on agricultural and processed foods is not in line with our biologically adapted diet and that this may be causing many of the new chronic illnesses that are associated with Western civilization [ 171 , 174 , 175 , 176 , 177 ].

6.3. Growing Your Own Food

Growing your own food means understanding seasonality and having the experience of gardening, both of which are strong nature experiences. A study by Church et al. [ 178 ] showed that those who grow their own food are happier than those who do not, accounting for a large number of possible socio-economic confounding variables, but not demonstrating a causal effect. Food growing has been linked with a variety of benefits, including self-fulfillment, identity affirmation, self-help, and mutual support [ 179 ], and growing your own food contributes to food safety and tastier, better quality food [ 180 , 181 , 182 ]. In fact, wanting better tasting food was the top reason respondents to a study cited for growing their own food [ 178 ]. It can also be a very satisfying practice [ 183 ], promotes skill development [ 181 , 184 ], and connects one to nature [ 185 ]. A final benefit of growing food, and the second most popular reason in the above-mentioned study, was economic savings [ 178 ]. Community markets with locally grown food have even been used to promote racial equality, as in the case of “Mo’ Better Foods” in the US [ 186 ], indicating that the benefits derived from food and taste can be far reaching, from the individual to the community scale. The expansion of food-growing from a male-dominated practice to a more equal and female-including practice has been studied [ 187 ], so it has implications for racial and gender relationships, and the local food movement (growing food locally) has been considered as a social movement [ 188 ]. Indeed, food ties us together and its use to bring people together socially is well documented [ 189 , 190 , 191 , 192 , 193 ]. Growing food or otherwise interacting in nature can bring us together socially and provide benefits, such as care farms [ 194 ] and nature-assisted therapy programs [ 195 ]. All of this suggests that community cohesion is one of the possible benefits of natural food.

While the sensory avenue of taste is the least explored in the literature, there is some indication that growing your own food has beneficial effects, flavours of foods have an effect on emotions, that organic (i.e., more natural foods) are perceived as tasting better and making one feel better, that traditional, more natural diets are better for our physical and mental health, and that growing your own food has positive effects on the individual and on the community.

The tactile sense is greatly underappreciated in humans, and its importance is often overlooked. Touch is the first sense to develop in utero [ 196 ], and it can affect people’s willingness to comply with requests, create bonds between people and groups, strengthen romantic relationships, and reduce stress as measured by blood pressure and heart rate [ 197 ]. Touch is crucial to love and social bonding, and there are many uses of tactile stimulation [ 198 , 199 ]. Contact is very important for humans [ 200 , 201 , 202 ], and contact comfort is necessary for baby monkeys, without which they become seriously psychologically dysfunctional and deprived [ 203 , 204 ].

In terms of nature experiences, one of the main avenues of experiencing touch is via animal petting. Animals in general have been found to provide us with positive benefits such as reduced blood pressure, self-reported increases in relaxation and comfort, and improved social responses in asocial and autistic individuals [ 205 , 206 ], and contact with animals results in greater benefits than landscape exposure, highlighting the importance of the senses other than vision to nature benefits [ 207 ]. Pets increase pain tolerance, decrease loneliness, enhance recovery from stress and frustration, and reduce the need for medical care [ 208 ], and while this may be from non-tactile factors such as companionship or increased exercise, animals are known for giving tactile comfort, so this may play a part.

Additionally, there is some literature on the haptic benefits of interacting with nature. This involves taking a “hands on” approach to nature, such as that practiced in forest schools, where children are encouraged to play and learn outdoors; this is believed to be one mechanism through which nature benefits can be delivered [ 209 ]. Children at these forest schools are believed to benefit from direct experience with nature in “confidence, social skills, language and communication, motivation and concentration, physical skills, and knowledge and understanding” [ 210 ], and motor skills have been found to improve more from play in the forest than in playground areas [ 211 ].

7.1. Cardiovascular and Mood Effects

Touching animals has been found to have beneficial cardiovascular effects [ 212 , 213 , 214 ], and it has been found that talking to and petting a dog is less arousing than talking to people [ 215 , 216 ]. Due to the “pet effect” [ 217 ], touching dogs can result in lower blood pressure and heart rate than other relaxing activities such as reading [ 218 ], and petting a dog lowers stress and decreases salivary and serum cortisol [ 219 ]. Arousal may be decreased by touch and this may be because the physical sensation of touch affects the cardiovascular system [ 217 ]. According to the “contact comfort hypothesis”, touch is a primary factor in reducing anxiety and sympathetic arousal [ 217 , 220 ]. Interestingly, blood pressure in individuals is affected by petting a dog regardless of their feelings towards animals, so it is not operant conditioning which results in lower pressure, but the act of touching itself [ 217 ].

These findings hold true for animals other than dogs as well. Short periods of petting resulted in lower state anxiety scores in stressful situations both with rabbits and with turtles, but petting a soft toy did not show the same results [ 221 ]. This was also found to occur independently of attitude towards animals. It appears that touching some living things regardless of attitude towards them results in positive feelings and lower stress, pain, and anxiety [ 222 , 223 , 224 ].

These benefits also accrue in the long term. Heart disease patients who were pet owners had a higher one-year survival rate [ 225 ], and pet owners were found to be healthier than non-pet-owners [ 226 ]. Pet owners have lower blood pressure, heart rates [ 227 ], and triglyceride levels [ 228 ], and petting effects on blood pressure were found to be strongest in individuals with the highest levels of blood pressure [ 220 ], so the benefits seem to be greater for those who are most at risk. While these studies of pet-owners are correlational and the effects may be due to factors other than touch (such as increased exercise from dog-walking), they are included here due to the general dearth of studies in the field, and are used to point to useful directions for future studies.

Human-animal interactions activate the oxytocinergic system, resulting in decreased social stress and endocrinological, psychophysiological, and psychosocial effects [ 229 ]. Oxytocin is produced by stroking [ 230 , 231 ], and an increase in plasma oxytocin was found in humans after 5–24 min of petting [ 232 , 233 ]. Oxytocin is found to increase social interaction [ 234 ], decrease stress [ 235 , 236 , 237 ], lower pain thresholds, produce anti-inflammatory effects [ 238 , 239 ], lower anxiety [ 240 ], and increase the function of the parasympathetic nervous system, resulting in increased digestive function [ 241 , 242 ]. Oxytocin may therefore be an important factor in the nature benefits received from touch.

Animals (for petting and interaction) have been used with psychiatric patients for their beneficial effects and have been shown to decrease fear and anxiety [ 243 ]. They are also used in companion animal therapy with outpatient psychiatric children [ 244 ]. Children with dog support were found to have lower cortisol levels correlated with their physical contact with the animal [ 245 ]. Animal assisted interventions result in lower depression levels [ 246 ], and touch was found to decrease cardiovascular activity in hypertensive patients [ 247 ]. Although not a treatment, it was found that college students petting live dogs showed an increase in IgA, an indicator of immune system function, indicating that petting animals may also enhance the immune system [ 248 ].

7.2. Non-Animal Nature Touch

One rather neglected area of research is the health and well-being effects of the non-animal aspects of nature through touch, such as feeling the grass under your feet, the water ripple through your hands, or the wind on your face (which could also be considered thermoception). We could locate no research focused on these topics, suggesting a significant gap in the literature. It would be interesting to look at blood pressure effects, for instance, of lying in the grass, to see if it provides additional benefits to those of just lying down. Part of the pleasure gardeners have in physical contact with the soil may be due to a sensual, touch component.

8. Non-Sensory Pathways

There is intriguing emerging evidence of at least three further distinct pathways for benefits of nature experiences that do not fit neatly in one or another of the senses, but that still require contact with nature, and we treat these in the following sections.

8.1. Phytoncides

Phytoncides are antimicrobial volatile organic compounds emitted by plants typically for defense against decay or attack by herbivores. Phytoncides permeate the air in natural environments, and are directly ingested by visitors to environments containing plants emitting them. They are not smelled or tasted as such, but simply ingested through inhalation. They are a popular topic of study in Japan, and widely believed to contribute to nature benefits experienced during nature walks known as “shinrin-yoku”, or “forest-bathing” [ 249 ].

Two kinds of phytoncides have been found to be antimicrobial on inhalation [ 250 , 251 , 252 , 253 ], while three have been found to increase immune system activity in vitro [ 250 ]. Overall, phytoncides are believed to decrease stress and increase relaxation, as in rats, they decrease spontaneous activity and reduce cardiovascular response to the stress of restraint [ 254 ]. They also prolong sleep, decrease anxiety, and depress the central nervous system in mice [ 255 ].

8.2. Negative Air Ions

Air ions are positively or negatively charged air particles that form when energy detaches an electron from one gas molecule and attaches it to another [ 256 ]. The energy for this ionization comes from radiation, cosmic rays [ 256 ], electromagnetic solar waves [ 257 ], waterfalls [ 258 ] thunder, radiant energy, and UV light [ 259 ]. Air ions are particularly abundant in natural places, such as forests and waterfalls, and they have been suggested as one of the potential mechanisms for the physiological and mood benefits of natural places [ 260 ]. Built environments tend to be characterized by ion depletion, with the indoors containing as little as 10% of the air ion concentration of the outdoors [ 261 , 262 , 263 , 264 ]. With urban populations spending as much as 90% of their time indoors [ 265 ], this could be a fundamentally important, yet essentially overlooked pathway for reduced mood and health through reduced contact with nature. Air ions are much more common in outdoor rural air that outdoor urban air, with the former containing in the range of 1200 ions/cm 3 and the latter about 500 ions/cm 3 [ 264 ]. This may be due to the tendency for small air ions to cluster around pollutants and drop out of the air column [ 266 ], and this ability to clean the air is itself a potential benefit of ambient air ions. Vegetation strongly influences the abundance of air ions, with forests having air ion concentrations on average of 1649 ions/cm 3 in comparison with 494 ions/cm 3 in open grassy parks as measured in southeast Queensland [ 267 ]. Plants directly produce air ions [ 267 , 268 ], and also draw up radon in the groundwater, which is a source of ions [ 267 ]. Recent surveys have found that mountains have the highest levels of air ions, while rural and coastal sites have moderate amounts and urban sites have the lowest [ 269 , 270 ].

Air ions have been believed to exert a biological influence since their discovery at the turn of the century [ 271 ], and a relationship has been noted between areas of higher air ion concentration (such as mountains and seashores), and areas traditionally prescribed for health treatment [ 272 ]. Yet the results of experimentation with air ions have been contradictory, with many experiments being flawed in not assessing the microclimate, improperly measuring ion concentration, and poor preparation of the experimental subject [ 272 ], so care should be taken when interpreting the results. There is enough evidence to warrant further exploration, but not enough to draw any firm conclusions.

Effects of Negative Air Ions

Air ions kill bacteria, increase plant and insect growth rate, and cause physiological and behavioral changes in people and other animals [ 273 , 274 , 275 , 276 ]. About 1/3 of the population is sensitive to air ions, and this portion of the population responds to the change in positive ion concentration that precedes certain warm, dry winds in a number of countries [ 277 ] by showing elevated symptoms of depression, lassitude, migraine, nausea, insomnia, and respiratory problems when these winds bring a high concentration of positive ions and a low concentration of negative ions [ 278 , 279 ]. Because negative air ions decrease the concentration of 5-hydroxytryptamine (5-HT) in mice, rabbits and guinea pigs, while positive ions increase it [ 280 , 281 ], and 5-HT in humans has been found to increase with the winds, it is believed that a “serotonin irritation syndrome”, contributes to the symptoms described above [ 277 , 282 ].

Negative air ions, on the other hand, increase thermal comfort and alertness, and decrease stuffiness, nausea, dizziness, and incidence of headaches by 50% in office workers [ 264 ]. After exercise, negative air ions decrease serum serotonin [ 283 ], and during stress, they decrease immunoreactivity, as well as state-trait anxiety inventory scores and correlate with a slight increase in performance on a word processing task [ 260 ]. In addition to a certain proportion of the population being more sensitive to air ions, those under stress or with ailments are also more responsive [ 284 , 285 ], and people with a lower autonomic lability score (more responsive to stress) show a higher response to air ions [ 286 ].

High density negative air ions are used as a treatment for seasonal affective disorder [ 287 , 288 , 289 ], and non-seasonally-depressed individuals showed a 27–55% improvement in depression, mood disturbance, and anger, during the first 30 min of administration of negative air ions in a placebo-controlled study [ 290 ]. Negative air ions also increase natural killer cell activity, and have anti-tumor effects [ 259 ]. Both positive and negative ions affect alpha brain wave activity, which indicates wakeful relaxation [ 291 , 292 , 293 ]. Asthma patients showed an 80% improvement using ionized aerosols [ 294 ], and ions have been used to improve burn healing [ 295 ]. In addition, anxiety was decreased in 80% of patients with anxiety syndrome [ 296 ].

In an example from animals, rats show an increase in learning and performance and decrease in fear with negative air ions [ 297 , 298 , 299 ]. While indoor ion depletion is correlated with depression and somnolence [ 300 ] and animals die in air filtered of ions [ 301 , 302 ], increased negative air ions levels stabilize mood, and increase vigor and friendliness [ 303 ]. They also increase alertness and performance, decrease tension [ 304 ], and increase reaction time, energy, and ease of concentration [ 305 ]. In Zhongxiang, a Chinese city known for having long-lived residents, higher levels of air ions were found both indoors and outdoors, a result which, while correlational, is believed to imply that higher levels of air ions contribute to longevity [ 306 ]. Negative air ions, therefore, may be an important contributor to the benefits derived from nature and are another possible mechanism through which nature benefits are delivered

8.3. Soil and Gut Microbes

In addition to the nutritional value of foods, we ingest a number of microorganisms with our food or directly from the environment, such as from soil. Some of these microorganisms persist as fauna within the gut with a number of beneficial effects. Humans coevolved with microbes for over 500 million years [ 307 , 308 ], and this has led to a symbiotic relationship, wherein bidirectional neuronal, hormonal, and immunological signals are exchanged between the gastrointestinal tract and the brain [ 309 ]. Saprophytic (soil) bacteria are commonly found in the gut, and while they cannot replicate there, were present in our ancestors due to exposure through mud and water [ 310 ]. Repeated exposure to these organisms was found to lead to a tolerance response to stress [ 311 ], and indeed continued exposure to environmental organisms is necessary to maintain the diversity of gut microbiota [ 312 ].

The human intestine has 100 trillion bacteria [ 313 ], or 10–100 times more bacteria than cells in the human body [ 313 , 314 , 315 ]. These bacteria come from the soil, water, animal feces, and spores in the air [ 308 , 312 ]. This gut microbiota, consisting of anaerobic bacteria, viruses, protozoa, archae, and fungi [ 316 ] is very important to central nervous system function [ 317 , 318 , 319 , 320 , 321 ]. However, the increase in time spent indoors and the sanitization of our living conditions has meant that we are exposed to fewer of these microorganisms than before, and thus reap fewer of the benefits.

8.3.1. Old Friends

It has been suggested that many of the modern world’s chronic diseases are actually inflammatory conditions resulting from the depletion from our environment of the microorganisms with which humans coevolved, the so-called “old friends hypothesis”, also known as the “hygiene hypothesis” [ 308 , 322 ]. These commensal organisms have a role in immunoregulation, and their absence leads to immunological dysregulation, with effects on behavior, emotion, and health [ 308 , 311 , 323 ]. Commensal microorganisms are also involved in the development of other organ systems, beyond the gut, including bones and the brain [ 324 ]. Indeed, microbiota-free mice are found to have altered brain chemistry and stress responses [ 317 , 320 , 325 ].

8.3.2. Chronic Inflammation and Disease

Urban populations have more mood and anxiety disorders (which are correlated with inflammation) than rural populations [ 326 ], and in low income (and therefore more rural) countries, inflammation increases with infection and then decreases afterwards. However, in high income countries, high levels of inflammation are found both with and without infection, such that the level of inflammation never falls [ 327 ]. In high income countries, as a result, the rate of chronic inflammatory disorders is high [ 328 ], and in both high income and urban areas, chronic inflammation and psychiatric disorders are more common than in low income and rural areas [ 329 ]. Overall, then, there is a strong link between gut biodiversity and mental and physical health.

This difference between low income and high income countries and rural and urban residents is exemplified by the difference found in the body microbiota of populations from different countries [ 312 ]. A study found that Italians have quite a different gut diversity to that of traditional people from Burkina Faso [ 330 ], and the skin microbiota from agricultural residents in Finland was more diverse than that from urban residents [ 323 ]. Gut microbe diversity was found to be highest in Amazonian Amerindians, then Malawians, and finally lowest in Americans [ 331 ]. People exposed to farm environments while young also have a lower incidence of asthma than the general population [ 332 ], and early farm exposure has been considered a protective device since the 19th century [ 333 ].

8.3.3. Effects of Microbiota

Commensal organisms produce serotonin, melatonin, gamma-aminobutyric acid, catelcholamines, histamine, and acetylcholine, all neuroactive molecules [ 308 ], and so can be expected to affect mood. A soil bacteria, Mycobacterium vaccae , has been show to increase emotional affect and cognitive function in cancer patients [ 334 , 335 , 336 ] by inducing Treg production, which downregulates inflammation [ 308 ].

Mycobacterium vaccae is an aerobic, temperate bacterium to which we are exposed in water, soil, and vegetation [ 337 , 338 , 339 ]. As an aerobe, it does not colonize the intestinal tract, but is considered a “transient commensal” [ 340 ]. It is believed that M. vaccae alters serotonin levels, affecting mood, arousal, and learning [ 341 , 342 ], and in mice, it lowered maze run times, mistakes, and anxiety behaviors [ 311 ]. This effect was temporary, only affecting the mice while the bacteria was in their system.

This data on bacterial effects on health indicates that the “old friends hypothesis” could be an avenue through which nature benefits are delivered. It is a rather well studied avenue through which nature benefits are delivered though it has not necessarily been linked with the nature benefits literature. Perhaps some of the benefits derived from living near greenspace [ 343 , 344 ] are due to the spores we ingest and organisms we are exposed to in the air, soil, and water.

9. Future Research

Overall, while the visual sense is relatively well understood as a pathway through which the benefits of experiencing nature are delivered, there are substantial deficiencies in our understanding of most of the other sensory and non-sensory pathways. As such, there are many key knowledge gaps and avenues to look into for future research ( Table 1 ). In general, we suggest explicitly looking at senses separately in nature benefits research. This can be done by repeating some experiments but using them on another sense, or on sensory-impaired individuals. Researchers could also build smellscapes and soundscapes to use as model systems, and perhaps couple these with visual virtual reality immersive experiences. One useful way to organize future research in this area is by hypothesizing the pathways leading from nature to the realized benefit and studying key links along this causal pathway [ 345 ]. Additionally, more work is needed on the duration of nature benefits, in particular to understand whether short term benefits, which are by far the most commonly studied type of benefit, translate into longer term effects. Other key research agendas include investigating potential synergies of multiple pathways, both sensory and non-sensory, and studying the differences between passive and active sensory avenues.

Knowledge gaps.

In the case of hearing, it would be interesting to partition different kinds of natural sounds to determine whether the benefits vary with the acoustic properties of the sounds (e.g., biophysical versus animal sounds or different kinds of bird song). Also, running experiments with visually-impaired individuals, such as exposing them to nature sounds, could provide insight into the nature benefits of sound.

The smell benefits literature could be usefully expanded by focusing on nature smells and the benefits we receive from them, using actual natural products to produce the smells, in the lab and also in situ. Comparisons among negatively and positively-valenced smells to give an idea of smell preference would be interesting, and could start to reveal information about how smells relate to preference and well-being. Finally, self-report studies looking at memories of preferred smells might provide some insight.

Taste remains highly neglected in the context of nature experiences, and some interesting research avenues might include clinical studies on the emotional effects of eating processed versus natural foods, ability to distinguish between processed and natural food, and cognitive effects of diet.

Touch is also rather poorly studied, and many of the references we reviewed were not directly about touch. However, there are intriguing indications that touching animals contributes to health and well-being, and we suggest that this be researched more thoroughly and experimentally where possible. There is also a significant gap in the literature with regards to touching non-animal aspects of nature, such as plants.

Most experiments with phytoncides take place in the lab as this is necessary to isolate the compounds, so an avenue of future research would be to conduct experiments in the field but attempting to isolate phytoncides as the active element. Measurements could also be taken of the distribution of phytoncides in the environment, such as through a park or forest, or in comparison to an urban area. Experiments could also look at how far phytoncides extend from natural areas, and whether they are released in measurable quantities from different kinds of urban greenery.

Because there is so much controversy over whether or not negative air ions actually do have an effect on humans, future research could focus on replicating existing fundamental studies with improved experimental structure and controls. Studies could also look at negative air ion distributions in nature, levels of negative air ions around different kinds of vegetation, and whether negative air ion sensitive individuals receive stronger benefits from experiences of nature.

Microorganisms living in and on people have been heavily studied, but this literature is only just beginning to be linked with the nature benefits literature. The field of microorganisms is quite well studied, but as regards future research, Matthews and Jenks note that, “research that incorporates a behavioral ecological perspective on brain-gut-microbe interactions is necessary” [ 311 ], meaning that we need to branch out in the microbiota research into human behavior and human ecology.

10. Conclusions

Many benefits that people receive from nature accrue through the five senses as well as at least three non-sensory avenues: sight, sound, smell, taste, touch, phytoncides, negative air ions, and microbes. Most research focuses on the visual nature benefits, and we have briefly reviewed this as well as examining the other pathways through which nature benefits are delivered, concluding that there is a need to broaden work beyond merely the visual sense and to take some experimental studies into the field. The idea that nature provides benefits beyond the visual has been touched on in the literature looking at some mood benefits derived from feeling connected to nature; this suggests that feeling connected to nature is enough to provide some psychological benefits [ 346 , 347 ]. We do not explore this at length here, but this alternate route should not be overlooked. Additionally, there is clear evidence of the benefits of exercising in greenspace or in simulated nature beyond that of exercising in other environments, implying that there may be another pathway involved here, although we do not yet know whether this is through the senses [ 348 , 349 , 350 ].

We have outlined the evidence that viewing nature both in pictures and through windows can improve health and mood; sounds such as birdsong and nature sounds provide restoration and enhance affect; smells provide numerous physical and psychological benefits; taste affects emotion, and traditional, natural diets have health benefits; petting animals can be very therapeutic; phytoncides can have a positive effect on our immune system; negative air ions affect our physical and mental well-being; and microbiota in the gut and the brain influence each other. We have looked at some sensory and non-sensory avenues, and it is possible that these pathways work in tandem or parallel, either synergistically, additively, or sub-additively.

Some limitations of our review are that it was narrative rather than systematic, and we suggest future studies take a narrower, more systematic approach that could focus on particular health or well-being outcomes, although at this stage it seems the literature would be too sparse for this kind of treatment of most questions. We also used correlational or preference studies in cases where there was little experimental research to show some of the potential sensory pathways for nature benefits, even if they have not been shown unequivocally. Our review focused on the benefits from nature interactions, but future studies could also include risks.

In the hunt for which mechanisms deliver nature benefits, it is easy to overlook the fact that they may, in fact, depend on multiple channels, and over the course of our evolutionary adaptation to natural environments all our senses have presumably become attuned to nature. Our senses often act in tandem, bringing a multitude of benefits at once. Humans are multi-sensory organisms, and we will only build a true picture of the interdependence of our health and well-being on nature once we understand how nature benefits are delivered through the full range of our senses.

Acknowledgments

Lara S. Franco was supported by an Australian Postgraduate Award and Richard A. Fuller by an Australian Research Council Future Fellowship.

Author Contributions

Lara S. Franco led the research, writing, concept development, and idea generation. Richard A. Fuller and Danielle F. Shanahan contributed to manuscript editing and idea generation.

Conflicts of Interest

The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.

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• 22 October 2024

Journals with high rates of suspicious papers flagged by science-integrity start-up

• Richard Van Noorden

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By analysing citations and authors’ publication records, Argos identifies ‘high risk’ papers that warrant further investigation. Credit: bernie_photo/Getty

Which scientific publishers and journals are worst affected by fraudulent or dubious research papers — and which have done least to clean up their portfolio? A technology start-up founded to help publishers spot potentially problematic papers says that it has some answers, and has shared its early findings with Nature .

The science-integrity website Argos , which was launched in September by Scitility, a technology firm headquartered in Sparks, Nevada, gives papers a risk score on the basis of their authors’ publication records, and on whether the paper heavily cites already-retracted research. A paper categorized as ‘high risk’ might have multiple authors whose other studies have been retracted for reasons related to misconduct, for example. Having a high score doesn’t prove that a paper is low quality, but suggests that it is worth investigating.

The papers that most heavily cite retracted studies

Argos is one of a growing number of research-integrity tools that look for red flags in papers. These include the Papermill Alarm , made by Clear Skies, and Signals, by Research Signals, both London-based firms. Because creators of such software sell their manuscript-screening tools to publishers, they are generally reluctant to name affected journals. But Argos, which is offering free accounts to individuals and fuller access to science-integrity sleuths and journalists, is the first to show public insights.

“We wanted to build a piece of technology that was able to see hidden patterns and bring transparency to the industry,” says Scitility co-founder Jan-Erik de Boer, who is based in Roosendaal, the Netherlands.

By early October, Argos had flagged more than 40,000 high-risk and 180,000 medium-risk papers. It has also indexed more than 50,000 retracted papers.

Publisher risk ratings

Argos’s analysis shows that the publisher Hindawi — a now-shuttered subsidiary of the London-based publisher Wiley — has the highest volume and proportion of already-retracted papers (see ‘Publishers at risk’). That’s not surprising, because Wiley has retracted more than 10,000 Hindawi-published papers over the past two years in response to concerns raised by editors and sleuths; this amounts to more than 4% of the brand’s total portfolio over the past decade. One of its journals, Evidence-based Complementary and Alternative Medicine , has retracted 741 papers, more than 7% of its output.

Argos risk-score ratings flag more than a thousand remaining Hindawi papers — another 0.65% — as still ‘high risk’. This suggests that, although Wiley has done a lot to clean up its portfolio, it might not have yet completed the job. The publisher told Nature that it welcomed Argos and similar tools, and had been working to rectify the issues with Hindawi.

Source: Argos.

Other publishers seem to have much more investigation to do, with few retractions relative to the number of high-risk papers flagged by Argos (publishers might have already examined some of these papers and determined that no action was necessary).

The publishing giant Elsevier, based in Amsterdam, has around 5,000 retractions but more than 11,400 high-risk papers according to Nature ’s analysis of Argos data — although all of these together make up just more than 0.2% of the publisher’s output over the past decade. And the publisher MDPI has retracted 311 papers but has more than 3,000 high-risk papers — about 0.24% of its output. Springer Nature has more than 6,000 retractions and more than 6,000 high-risk papers; about 0.3% of its output. ( Nature ’s news team is independent of its publisher.)

Chain retraction: how to stop bad science propagating through the literature

In response to requests for comment, all of the publishers flagged as having the greatest number of high-risk articles say that they are working hard on research integrity, using technology to screen submitted articles, and that their retractions demonstrated their commitment to cleaning up problematic content.

Springer Nature says that it rolled out two tools in June that have since helped to spot hundreds of fake submitted manuscripts; several publishers noted their work with a joint integrity hub that offers software which can flag suspicious papers. Jisuk Kang, a publishing manager at MDPI in Basel, Switzerland, says that products such as Argos can give broad indications of potential issues, but noted that the publisher couldn’t check the accuracy or reliability of the figures on the site. She adds that the largest publishers and journals would inevitably have higher numbers of high-risk papers, so that the share of output is a better metric.

The publishing brands with the greatest proportions of high-risk papers in their portfolios are Impact Journals (0.82%), Spandidos (0.77%) and Ivyspring (0.67%), the Argos figures suggest. Impact Journals tells Nature that, although its journals have experienced problems in the past, they have now improved their integrity. The publisher says that there were “0% irregularities” in its journal Oncotarget over the past two years, owing to the adoption of image-checking tools such as Image Twin, which have become available only in the past few years. Portland Press, which has 0.41% of high-risk papers in its portfolio, says that it has taken corrective action, bringing in enhanced stringency checks.

Journal risk ratings

Argos also provides figures for individual journals. Unsurprisingly, Hindawi titles stand out for both the number and proportion of papers that have been retracted, whereas other journals have a lot of what Argos identified as high-risk work remaining (see ‘Journals at risk’). By volume, Springer Nature’s mega-journal Scientific Reports leads, with 450 high-risk papers and 231 retractions, together around 0.3% of its output. On 16 October, a group of sleuths penned an open letter to Springer Nature raising concerns about problematic articles in the journal.

Paper-mill detector put to the test in push to stamp out fake science

In response, Chris Graf, head of research integrity at Springer Nature, says that the journal investigates every issue raised with it. He adds that the proportion of its content that has been highlighted is comparatively low given its size.

Journals with particularly large gaps between the number of retracted works and potentially suspect papers include MDPI’s Sustainability (20 retractions and 312 high-risk papers; 0.4% of its output) and Elsevier’s Materials Today Proceedings (28 retractions and 308 high-risk papers; 0.8% of its output). Elsevier’s Biomedicine & Pharmacotherapy has the highest proportion of high-risk papers — 1.61% of its output.

“The volume of fraudulent materials is increasing at scale, boosted by systematic manipulation, such as 'paper mills' that produce fraudulent content for commercial gain, and AI-generated content,” says a spokesperson for Elsevier, adding that in response “we are increasing our investment in human oversight, expertise and technology”.

Argos’s creators emphasize that the site relies on open data collected by others. Its sources include the website Retraction Watch, which maintains a database of retracted papers — made free through a deal with the non-profit organization CrossRef — that includes the reasons for a retraction, so that tools examining author records can focus on retractions that mention misconduct. The analysis also relies on records of articles that heavily cite retracted papers , collated by Guillaume Cabanac, a computer scientist at the University of Toulouse, France.

Although Argos also follows analysts that focus on networks of authors with a history of misconduct, other research-integrity tools also flag papers on the basis of suspicious content, such as close textual similarity to bogus work, or ‘tortured phrases’, a term coined by Cabanac, when authors make strange wording choices to avoid triggering plagiarism detectors.

What makes an undercover science sleuth tick? Fake-paper detective speaks out

“Both approaches have merit, but identifying networks of researchers engaged in malpractice is likely to be more valuable,” says James Butcher, a former publisher at Nature-branded journals and the Lancet , who now runs the consultancy Journalology in Liverpool, UK. That is because AI-assisted writing tools might be used to help fraudsters to avoid obvious textual tells, he says. Butcher adds that many major publishers have built or acquired their own integrity tools to screen for various red flags in manuscripts.

One of the trickiest issues for integrity tools that rely mostly on author retraction records is correctly distinguishing between authors with similar names — an issue that might skew Argos’s figures. “The author disambiguation problem is the single biggest problem the industry has,” says Adam Day, founder of Clear Skies.

De Boer, who formerly worked at Springer Nature, says that anyone can create an account to access Argos for free, but Scitility aims to sell a version of the tool to big publishers and institutions, who could plug it directly into their manuscript-screening workflows.

Butcher applauds the Argos team’s transparency. “There needs to be more visibility on journals and publishers that cut corners and fail to do appropriate due diligence on the papers that they publish and monetize,” he says.

doi: https://doi.org/10.1038/d41586-024-03427-w

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