Why is biodiversity so important? Biodiversity makes life possible. It is a prerequisite for our ecosystems to function and provide clean air and water. Variety of life is responsible for regulating the flow of both freshwater and tidal waters, for reducing carbon and slowing climate change and for buffering the effects of storms and natural disasters.
Biodiversity ensures that we have important ecosystems like mangroves, coral reefs, forests, grasslands and wetlands that provide habitats for countless species even those required for crop production, as well as habitats for other important sources of food and livelihood: fish, birds and wildlife.
This makes resilience of our food systems possible and is essential for our survival.
Biodiversity is critical for safeguarding global food security
Biodiversity is a prerequisite for a balanced diet supplying all the vitamins and minerals and micronutrients necessary to maintain good health, as no single food source can provide all the nutrition our bodies need.
Presently 95 percent of our food is produced directly or indirectly on our soils . Biodiversity is necessary to support the community of organisms that create and maintain fertile soils for food to grow.
Diversity of native life forms is required to support the pollinators for crops and to support the insects and other species that control pests and parasites of crops.
Any farmer can tell you that crops are subject to attack by pests, bacteria and mildew or different types of fungi. That is the reason agribusiness operators genetically modify seeds and that is why they spray copious amounts of chemical pesticides on their fields. They also inundate the crops with fertilizers, and at the end of the season they may also heavily spray defoliants to simplify harvesting of crops such as cotton.
In the natural world there is a web of predators keeping pests and bacteria in check. Mimicking the natural world by planting a diversity of crops rather than a monoculture helps to ensure that there will be a variety of species to maintain a natural balance, a natural community where a healthy percentage of the plants can thrive.
Providing natural predators, biodiversity can play a key role in eliminating the need for food and agricultural producers to rely upon pesticides and fertilizers, environmentally harmful externalities with cascading adverse impacts that include soil degradation and the eradication of pollinators.
All of these processes are required for a sustainable crop production.
Addressing the loss of genetic diversity in food crops
Biodiversity is an encompassing term, spanning the diversity of life from genes to ecosystems. When discussing food security, the conversation within the farming and agricultural communities frequently focuses on genetic biodiversity, that is a concern for the decreasing diversity of species (including within species) and the variety of plants.
The decline is very real. An example: in the 1800s in America, there were 7,100 named varieties of apples. Today 6,800 of those are extinct . In fact, globally 75 percent of plant genetic diversity has been lost since the 1900s .
The diversity of species we rely upon for food production globally is quite narrow and this in itself is widely seen as a potential threat to food security.
- Only nine species comprise 66 percent of our total crop production.
- Only eight domesticated mammals and birds provide over 95 percent of the human food supply from livestock.
- And only ten species provide 50 percent of total aquaculture production .
What is not produced is threatened with extinction. What is grown, is threatened not only by disease and pests, but agroterrorism , the use of biological agents to deliberately damage livestock or crops, a problem that may accelerate as climate change incites conflict over resources.
The loss of genetic diversity is of particular concern as the earth gets hotter and the food sources we presently rely upon, whether animal, bird, marine life or plant crops, may well be unable to adapt to the changes in land and temperature wrought by global warming.
Consider for example that a crop not presently being widely produced may prove an invaluable food source in the future if our present crops prove unable to adapt. Given that it won’t be long until the coolest growing season may be hotter than the hottest on record, this is not an unlikely scenario.
Recognizing this, the framers of the UN Convention for Biological Diversity specifically articulated the goal not only of safeguarding ecosystems and species, but also of safeguarding their genetic diversity.
Safeguarding the genetic diversity of our food sources
Concerned about the loss of genetic diversity in agriculture, groups have formed to collect and securely store seeds. The most well-known is the Svalbard Global Seed Vault where crop seeds that have been collected are stored in a secure vault on a remote island in Norway, ostensibly safe from social conflict and natural disasters.
Collections across the globe vary in scope, some collected by governments and some by individuals, some storing only heirloom seeds and some accepting all seeds. Some save their seeds and perform germination tests periodically to ensure viability and some make their seeds readily available for restoration projects, when for example a grassland has been destroyed.
Capturing and saving bird, animal and fish populations is not feasible. We are learning that living organisms cannot often be removed from their ecosystems and still flourish. An organism is not like a watch whose pieces can be taken apart and reassembled.
We have witnessed the failure of birds removed from the wild unable to thrive outside their natural habitat. More recently we are learning that even trees of different species within an ecosystem communicate and collaborate with each other through underground networks . And when transplanted with a single species, the new forest is not as strong as a biodiverse forest . It is possible that the stress causing “transplant shock” when a living plant is relocated involves more factors than we have traditionally considered.
Seeds however, by their nature are meant to be dispersed and do not pose the considerations that uprooting living species do. As long as they are planted under appropriate conditions, they can usually be prompted to grow. Safeguarding their genetic diversity appears to be a challenge we can meet.
Food scarcity is already a problem for many, and food security is becoming an even more serious issue as our global population grows. As you are reading this, 8.9 percent of the 7.8 billion people on earth is hungry .
Producing more food without expansion into natural habitats and causing further environmental degradation and pollution, which then causes even further loss of biodiversity in an already precarious world is a daunting challenge to say the least.
Even at our current global population, biodiversity is critical for safeguarding food security and our production of that food must in turn protect and promote biodiversity.
Biodiversity helps reduce the spread of infectious disease
Biodiversity has proven to be an important source of genetic resources for the development of many treatments and vaccines used in both traditional and modern medicine . Among plant-derived medicines are modern medicines currently being used to treat malaria, certain cancers, liver diseases, heart diseases and Alzheimer’s .
It is impossible to delve into the subject of whether biodiversity reduces the spread of infectious disease without coming upon an entire body of literature among scientists concerning the “dilution effect.”
Conversely, a loss of biodiversity will result in an increase in diseases. This is where the balance of nature has been upset. Where there is a decreased number of competing species, allowing another species to increase inordinately and that species is infected, the spread of disease can become rampant without any natural check .
Studies have shown that in a more biodiverse system, a disease does not significant affect any population numbers. But sometimes with biodiversity loss, a particular pathogen or parasite who has lost its primary host will be compelled to attack remaining potential hosts who have not evolved to resist the attack. The infection risk and the stakes for survival are higher then .
While arguments go back and forth depending on which species has been lost from the food web, in general a healthy system is better able to confront an infectious disease.
An intact ecosystem is a healthy ecosystem, having evolved with natural checks and balances to keep it strong, with endemic species having evolved adaptations fine-tuned to the dynamics of the ecosystem, perhaps over millions of years.
A fragmented ecosystem, where many of the species are missing is already struggling. Once a species drops below its “minimum viable population”, that is the smallest isolated population likely to survive in the face of foreseeable events , a disease can easily take hold. The effects of a fragmented ecosystem losing its natural resilience and becoming more susceptible to pathogens and disease incidence is well documented [16,17].
Invasive species are a threat to biodiversity & our health
We are facing two problems in the modern globalized world which promote the easy facility of spreading infectious diseases while threatening the very biodiversity which would provide the best defense.
The first is disease spread by an invasive species (an organism that causes ecological or economic harm in a new environment where it is not native) .
Many invasive species are introduced into a new environment inadvertently, attaching themselves to travelers, their luggage, shipping crates and even on and in transport vehicles, like the rudders of ships.
Exotic pets can be released intentionally or accidentally. It is believed that Hurricane Andrew’s destruction of a pet store was responsible for the uncontrolled population of Burmese pythons whose number and appetites have nearly decimated the once-prolific small mammal population in Florida’s Everglades. Ornamental plants can spread into the wild.
Other invasive species may migrate due to climate change or loss of habitat. But where these invasive species carry disease, the native wildlife may well not have any evolved defenses to the disease, a problem compounded when the ecosystem is not able to keep in check a species that has no predators there and is on the road to making a monoculture of a biodiverse ecosystem .
Many non-native species are transported intentionally and legally, only to have it discovered at a subsequent date that they are carrying a disease. While yet others are traded illegally .
The UN Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) is an international agreement against trading endangered species. Many countries also regulate the trade of livestock and poultry to insure against pests and diseases entering their territories or spreading within them, but their actual enforcement is another matter entirely.
The spread of zoonotic diseases
The second, not necessarily mutually exclusive threat is the emergence of zoonotic diseases, diseases transferring from animals to humans.
Our current COVID19 pandemic is one such disease, as are many of our recent viruses to reach epidemic proportions: the West Nile virus, Ebola, H1N1, the Avian flu, HIV/AIDS and the Zika virus.
Zoonotic diseases are spread where humans are in close contact with animals carrying the disease. This can happen in the black-market trade of smuggling illegal wildlife.
Wildlife is poached for several different reasons. Some buyers simply want exotic pets. Some use animal body parts like ivory tusks for trophies, or ornaments, animal skin or pelts for clothing or, as in the case of pangolin scales as medicines or as a delicacy to eat.
Spillover diseases also take hold in the human population in places where a local culture relies on bushmeat for sustenance. Or it can happen where human settlements have encroached on native habitats and the interaction with animals is simply too close.
Consider children playing in a cave with infected bat droppings. It is all too easy for a disease to be transferred from hand to mouth or respiratory tract. In the latter case, the native biodiversity has already been eroded by human sprawl.
The unfortunate irony is that the remaining habitat may hold the answer to reducing the spread of the spillover disease. Biodiversity not only keeps populations in check, but it is quite possible that in its evolution of adaptive mechanisms, it holds the antidote for the infected animal’s disease.
For example, we know that bottleneck dolphins rub their entire bodies against a soft coral resembling a bushy plant, the Gorgonian in their natural habitat in the deep sea, a coral believed to have anti-inflammatory and antimicrobial properties .
Or conversely, in the example of the bats living in close proximity to the humans, it may be that human encroachment has destroyed the antidote to the disease carried by the bats.
Biodiversity is an essential part of the solution to climate change
Biologically diverse ecosystems serve as buffers to climate change by absorbing the excess greenhouse gas emissions which are the primary contributor to climate change.
Our primary natural carbon sinks are:
- the ocean
Plants take carbon dioxide from the air for photosynthesis. The United Nations Forum on Forests recently concluded that forests are absorbing and storing about 30 percent of current levels of carbon emissions from fossil fuels and industry into their biomass, soils and wood products.
Oceans are important in the carbon cycle
Our oceans are major sinks for storing carbon. Phytoplankton, tiny ocean plants, at or near the surface of the ocean absorb at least 30 percent of the carbon dioxide in our atmosphere through photosynthesis . The UN Global Development Research Center puts that number even higher, estimating it is between 30 and 50 percent . The actual quantity has become higher each year as our emissions have increased.
Zooplankton and other small marine creatures then eat the phytoplankton. Bigger fish eat the zooplankton and on up the food chain. When the marine life dies, or defecates, the carbon falls to the bottom of the ocean, far away from our atmosphere. That is why it is called a carbon sink.
But the carbon cycle is off…
Presently we have so much carbon dioxide in the air that when it rains, the rainfall is acidic. This acid rain is changing the chemical composition of the ocean waters and adversely affecting marine life.
The water can be too acid to allow shells to form. Of deep concern are the adverse effects on the zooplankton’s ability to form shells. Zooplankton are small marine creatures who play a large part in transporting excess carbon to the ocean floor where it is sequestered.
Equally as affected coral reefs as nurseries and important habitat for many fish species, along with the loss of many other shelled aquatic creatures, are vastly changing the dynamic of life underwater, removing key species from some food chains. Some areas are already experiencing an overpopulation of jellyfish who are apparently better able to adapt to the warmer, acidic water than some of their predators .
Studies show that a high biodiversity of marine life can mitigate the impact of ocean acidification .
A second important reason for maintaining the natural biodiversity of the ocean is that phytoplankton contributes 50 to 85 percent of the oxygen in our atmosphere . Obviously we need air!
We cannot lose our phytoplankton and yet it is under serious threat, not only from larger predators than zooplankton, who are filling in the void where the number of zooplankton is diminished, but because phytoplankton likes cool waters.
Biodiversity supports terrestrial carbon sinks
Soil is also a major carbon sink. Grasslands cover approximately 25 percent of the Earth’s land surface and contain roughly 12 percent of the terrestrial carbon stocks. It is mostly found in the fibrous root system from which it transfers to soil, resulting in fertile soil.
Additionally, when plants die some of their carbon is transferred to the soil.
Sadly, our grasslands are fast disappearing from agricultural encroachment and from desertification and climate change. It is estimated that only ten percent of the world’s grasslands are intact . Restoring these lands to healthy ecosystems will increase our ability to sequester carbon.
In addition to carbon sequestration, biodiversity helps by buffering communities from the impacts of rising sea levels and the increasingly severe storms caused by climate change. Mangroves and other plants with strong roots systems can help resist the winds, tidal surges, and erosion.
Too, the trees of a healthy biodiverse forest regularly release water vapor into the sky, adding to clouds that provide rainfall sometimes hundreds or thousands of miles away . This can be an especially welcome mitigation to degraded lands and those areas suffering from drought.
Climate change is either directly or indirectly responsible for degradation of our soil, rendering it unfit either for supporting plant life or for filtering water. But the soil of a biodiverse ecosystem is rich in microorganisms. Where the soil is rich, it is capable of filtering water that falls to the ground in the form of precipitation, rendering it suitable not only for drinking, but for feeding into rivers and tributaries that support aquatic life and plants. And so the important water cycle forms.
Biodiversity is good for the economy
Direct contributions to the economy from biodiversity include production of food, medicine, clothing, materials and energy. These are all valuable to the economy if they are sustainably harvested and produced.
Biodiversity directly sustains:
- pharmaceutical industries
It underpins all economic activity by providing:
- stable natural hydrological cycles
- fertile soils
- beautiful landscapes
- balanced climate
- storm protection
- soil filtration
- pest control
- genetic diversity
- nutrient provision
- disease protection
Even the World Bank says that investing in nature makes sound economic sense, stating explicitly, “Healthy ecosystems, supported by rich biodiversity, are a primary source of growth, resilience and prosperity.” And conversely, according to the World Economic Forum half of the global GDP, $44 trillion is exposed to risks from nature loss [31,32].
Biodiversity is essential for sustaining livelihoods
One needs a livelihood to provide the basics: food, shelter, clothing and medicine. Many livelihoods rely directly upon biodiversity. For example, biodiversity means resilience to the farmer who has planted many different varieties of crops and thus has other crops to fall back on when some crops fail.
In addition to the commercial industries listed in the previous section, which employ billions of people, it is appropriate to discuss the indigenous cultures at the fringe of the biodiversity hotspots.
This is where it is most critical to ensure a sustainable economy so that the integrity of the biodiversity hotspot can be conserved locally. If the indigenous people cannot make a good livelihood and survive living in harmony with the preservation of the ecosystem, then they will be inclined to “sell” their environment to those would destroy it, be it a timbering company, an agriculture business or a mining operator or anyone with commercial interests adverse to conserving their biodiverse environment and consequently, our planet.
When we look to the United Nations sustainable development goals, adopted by all UN members and ascribed to by private businesses as well as many organizations, we realize that we are witnessing a paradigm shift from thoughtless development to a global society organized on principles of ending poverty while improving health and education, reducing inequality and spurring economic growth, all while working to preserve and restore our oceans and forests and tackling climate change .
In short, the goals support helping each other and living in harmony with nature. Both governments and non-government organizations have embraced protecting the biodiversity hotspots as the urgent task and have moved into many of these areas to address the threats in the most integrated way possible, so as not to cause other inadvertent adverse effects.
Sustainable livelihoods & the biodiversity preservation work
Let’s examine how biodiversity can be preserved and maintained in an internationally recognized biodiversity hotspot while creating sustainable livelihoods for the surrounding communities.
A success story of the Colombian cloud forest mountains
The Serania El Pinche is nestled in the southwest mountains of Colombia and despite its remote locale, this Key Biodiversity Area in the mountain cloud forest is threatened by encroaching coca plantings, logging and unregulated fishing.
These activities have not only been degrading the natural environment, home to 350 bird species and many amphibian, butterfly and beautiful flower species, but members of the surrounding three communities have found themselves at odds with each other, each concerned with his own ability to make a livelihood and not having developed a common goal of conserving the biodiversity.
The Critical Ecosystem Partnership Fund, a partnership of conservation groups moved in to help. The World Bank also works on conservation projects in the area and these alliances share the common approach of educating indigenous peoples, bringing them together to find a common goal of conserving the natural biodiversity of their homeland, preserving their unique cultures, and teaching them how to care for the biodiversity while creating livelihoods that don’t harm the environment.
The locals have done the legwork to bring thirty communities in an alliance to protect their environment while creating jobs. They have greenhouses protecting their crops through both dry periods and periods of heavy rain. They have learned how to use water more efficiently. They have learned to recycle and use organic waste as fertilizer. The net result of these improvements is that previously impoverished families are now able to produce not only enough organic produce for themselves, but also produce enough to sell and make money.
Five savings-and-credit funds have been established in the area and families are able to leverage new economic resources through conservation incentives. Fifteen households now boast eco-efficient stoves both reducing the requirement for firewood and improving air quality and respiratory health.
In a nearby related project, the World Bank has funded teaching local communities aquaculture, sustainable agro-forestry systems, sustainable tropical cattle husbandry and the utilization of renewable energy for farming .
Without this initiative, their beautiful cloud forest would have been lost to commercial interests, providing only short-term jobs at best. They would have had no firewood left to heat their homes, and no fish or wildlife to eat. They would not have the food security they have now with the greenhouses.
Money flowing into the area in turn will help raise the quality of life so that the children can be educated and find personal fulfillment in a sustainable world.
Biodiversity is an integral part of culture and identity
In Freud’s essay on “Mourning and Melancholia” (1917) he writes of a melancholic who “knows whom he has lost but not what he has lost in him” and hence is never able to get over the unconscious loss. How will we feel when we can no longer take long walks in nature and hear the birds and the frogs? Will we even grasp the root of our disassociation from a lost web of life?
In some cultures, such as the Aboriginals in Australia who believe that all of life is a single interconnected organism and have watched as their sacred places are destroyed in the name of building infrastructure, the loss is a blow to their identity. It is a heedless desecration of their very creation myth.
Likewise, the Native Americans have had their entire way of life, their sacred spots and much of their civilization destroyed and yet a few million remain, many notoriously displaced, drowning themselves with alcohol in casinos in a culture so unlike the natural world where they read signs from the Great Spirit through the behavior of animals.
Their environment, now destroyed, gave their entire existence meaning. Their rituals included giving thanks to the animals whose lives they took for food. They would often don the skins or the hollowed head of the animal whose life was taken as a symbol of taking on the traits of the animals and perform rituals, dance-stepping like the animals in a show of deep respect for the natural world around them. Their lands are gone, many of the animals extinct.
We see this disassociation too in those who have left their cultures behind and do not adjust well to their new locales . It is not uncommon for the world’s many refugees to suffer mental illnesses including adjustment disorder when they are forced to uproot from their homes .
A resettled refugee might not be able to find an ingredient in her new land that she had used in baking, and thus can no longer make traditional foods. This may seem like a small matter in a bigger picture of perhaps escaping barbarism, but losing a tradition is a loss of self-identity.
Alliances working to preserve and restore the world’s biological diversity are interested in preserving the cultural identity of indigenous peoples. The skills they are being taught incorporate their native traditions as much as possible.
While a process may be taught to dye a fabric using less water or to grow the plants providing fabric by utilizing more sustainable methods, indigenous people are still encouraged to use the patterns that have meaning to their tribes and have been handed down for generations.
Biodiversity is linked to a cultural diversity & indigenous knowledge
The recent interest in the use of plants with psychedelic properties to heal depression-related disorders has brought the Shipibo tribe in the Amazonia rainforest in Peru into the spotlight. They have been able to hold onto the tradition of shamans, or healers administering the Ayahuasca brew for spiritual purposes for two thousand years.
We have come to realize that cultural diversity can be closely linked to biodiversity, as many ecosystems have a symbiotic relationship with cultural identity. Religious rituals strengthen this relationship . Where a plant is used in a religious ceremony, such as the ayahuasca, the indigenous people are sensitive to the importance of conserving it in nature. It is for these reasons that an alliance with the local population is the best method to ensure that biodiversity flourishes.
Identity with place can be a powerful element of self-identification. In the early nineteenth century Simon Bolivar emboldened the indigenous peoples of South America to rebel against the social injustices and rapacious commercial environmental degradation under Spanish colonialism with a rally cry inspired by the observation of his explorer-naturalist friend Alexander von Humboldt: The land did not belong to the Spaniards. It belonged to the natives. Their natural world was a reflection of its people: strong, vigorous and beautiful !
The people could see that and joined together to reclaim much of South America.
Biodiversity has positive health impacts
Biodiversity can lower your blood pressure and may even reduce your belly fat! It can bestow a sense of belonging, a feeling of harmony with one’s environment. It can instill a sense of awe for the world around us.
Any urban dweller who hankers for a visit to the countryside, the mountains or the beach will tell you how much better they feel when they return back.
In Japan, they actually have a name for this spiritual enrichment: “forest bathing.” The Japanese Ministry of Agriculture, Forestry and Fisheries instituted a national “forest bathing” program in the early 1980s as a response to an inordinate number of urban dwellers suffering depression and anxiety from being overworked and overloaded with the noise and congestion in their daily lives.
The culture that brought us Zen and mindfulness was now recommending a remedy for stress: immerse yourself in the atmosphere of the forest – breathe it in. In fact, the government has since designated a number of forest bathing reserves where the rules are to simply be quiet and relax. No running, no work. Just breathe deeply and be present in the moment.
And now, nearly 40 years of extensive research has only confirmed a wide range of health benefits including:
- reduced stress
- increased happiness
- more energy
- feeling a sense of awe witnessing the exquisite beauty of nature
- immune function
- neurological sensitivity
- heart rate and blood pressure improvement by spending time in the forest
Cortisol levels, the hormone released when we sense danger, are lowered. High cortisol levels, common when one feels stressed can cause not only inflammation, but the accumulation of belly fat .
Why exactly do we feel better when we are surrounded by nature?
Trees and plants emit substances called phytoncides that kill potentially harmful insects and bacteria. Studies have shown that when people inhale phytoncides, their body immediately begins functioning in a more balanced way.
The body begins to regulate its functions and changes the way it protects itself against viruses, bacteria, and cancer.
A 2007 study published in the International Journal of Immunopathology and Pharmacology found that breathing in phytoncides boosts the immune system and generates expression of anti-cancer proteins. These effects may last between seven and thirty days .
And too, the UN Cooperation on Health and Biodiversity reports that a sensitivity to ecology and respect for other species has shown to reduce anti-social behavior in children and young adults.
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