Forests make up approximately one-third of the earth’s total land mass, but every year we are losing more and more of them. What are the causes of deforestation, and what impact does this have on human health? We know that forests are a vital part of oxygen production, as well as the absorption of carbon dioxide. Forests help to purify the air we breathe, the water we drink, and the environment we live in. They also provide a home to hundreds of thousands of different organisms, many of which are endemic to the area they live in. About 80% of the world’s terrestrial species are found in forests! Trees produce thousands of therapeutic terpenes, giving us health benefits we have only begun to understand. When we begin to lose our forests, what happens to us?
Benefits of Forests
Forest ecosystems are good for more than just producing oxygen and purifying water. Billions of people rely on them for sources of food, medicine, clothing, shelter, and fuel.
Beyond what they can physically offer, forests also offer a place for recreation and peace. Many people who are looking for an escape from the city make their way to a local park or nature preserve. Some may choose a forested area for their daily morning run, while others may go on a weekend camping trip. Those who aren’t out for the physical activity may come to the forest simply to get a moment of peace in the midst of a busy life. Being able to breathe in the fresh air, smell the flowers, hear the birds, and listen to the wind in the trees can be a welcome escape from the busy city.
Forest Bathing and Terpenes
The peace that you feel from a walk in the forest actually has a bit of scientific reasoning behind it. Known as forest bathing, or Shinrin-yoku, the act of talking a mindful walk through the forest can benefit you both physically and emotionally. You don’t need to spend hours in the forest to reap these benefits. Simply taking 20 minutes out of your day to take in the forest through all of your senses can do wonders. This process has been shown to improve immune system function, reduce cortisol levels, lower blood pressure, improve mental clarity, and increase the sense of general wellbeing.
Many of the health benefits that forests offer come from the presence of terpenes, which are a type of secondary metabolite from plants. While terpenes don’t play a key role in the survival of the plant, they do help the plant thrive under certain conditions. These secondary metabolites often serve defense purposes. Breathing in the forest air allows us to breathe in all of these powerful terpenes. While they help reduce feelings of stress and anxiety, they also give our bodies an extra health boost.
Forests provide a healthier environment, a place for recreation, and a place of peace. As we cut down more and more forests, what will we be left with?
Causes of Deforestation
People have already cut down approximately half of the world's tropical forests. Between 6% and 12% of the remaining global forests fall every year. A number of different factors cause deforestation, with industrialization being a large catalyst.
- Forest fires : Environmental conditions or human negligence can cause forest fires. Lightning is the largest natural cause of forest fires, and during a hot, dry, summer, a single lightning strike can eradicate large patches of forest. When human activity causes fires, it is often a poorly extinguished campfire, a forgotten cigarette butt or fireworks. Many national parks and other recreation areas often have a complete fire ban during the summer months for this reason.
- Harvesting wood for fuel: While newer homes no longer rely on wood stoves for central heating, there are still many people who rely on wood for heating and cooking.
- Mining: In order to mine minerals and metals, companies clear trees and other vegetation. When they do clear land, bulldozers and excavators are brought in to extract these metals and minerals from the soil. Companies use chemicals to separate minerals from ore and toxic waste remains.
- Drilling: The demand for oil is constantly increasing, and deforestation results from increased demand. Trees are cut down to make roads and camps, while toxic chemicals from the process can negatively affect soil and water sources.
- Expanding agricultural land: The increasing demand for certain agricultural products are causing plantations and farms to expand at a rapid rate. This expansion often comes at the expense of forested land. In 2008, the Guinness Book of World Records named Indonesia the "fastest forest destroyer." Indonesia is the largest producer of palm oil, which is one of the most devastating reasons for deforestation.
- Expanding infrastructure: Constant urbanization of forested areas leads to deforestation. As the population of an area grows, people cut down forests to make room for new cities, roads, schools, and factories.
- Illegal logging: Illegal logging is the number one cause of worldwide deforestation. Illegal loggers cut down over 15 billion trees every single year. Myanmar, Peru, and Indonesia have the largest rates of illegal logging in the world, while the United States is the largest importer of illegal timber.
- Ranching livestock: Cattle ranching is the largest cause of deforestation in the Amazon. Brazil is the largest exporter of beef in the world, and 450,000 square km of deforested land in Brazil is now cattle pasture. 1
Impact of Deforestation on Human Health
Deforestation of tropical forests in Borneo to make room for palm plantations is leading to an increase in diseases such as dengue fever and malaria. In an area that has experienced rapid deforestation, there has been an alarming increase in the number of malaria cases. This particular form of malaria was originally only in macaques. As people began to cut down forested areas, the primates moved into smaller and smaller habitats. Because of close quarters, the disease spread through macaques populations. As humans began to work on the palm plantations, mosquitoes found it easy to carry the disease from primates to people.
The outbreak of malaria in Borneo is only one of many infectious diseases that have gained traction as a result of deforestation. The Zika virus, yellow fever, dengue fever, and other pathogens pass between mosquitoes and animals. Because these diseases evolve over time with animals, they often do not produce any symptoms. Deforestation leads to an increase in mosquito breeding, as well as a decrease in natural habitat. Mosquitoes and animals cram into smaller and smaller habitats. As human begin to frequent these habitats, the disease spreads. 2
More Effects on Human Health
The rise in disease is also accompanied by the loss of important medicinal plants. Approximately 25% of all natural medicines are originally from rainforests, and there are plenty more species that we haven't studied. As these plants begin to go extinct, we could be losing valuable medicine.
As we cut down forests, many people who rely on them for food, water, shelter, and fuel don't have these basic necessities. The loss of clean water and biodiversity continues to negatively affect those who aren’t living within a forest ecosystem. Do you enjoy a cup of coffee every morning? Many of the world’s coffee species have a large chance of becoming extinct due to deforestation. 3
Impact of Deforestation on the Earth
Deforestation negatively affects human health in many different ways, yet humans are not the only species threatened by the loss of forested land. Many species of plants and animals that live in forests - especially rainforests - are endemic to that particular habitat. If that habitat is lost, they are not able to thrive in a different ecosystem. Loss of forests is the major cause of extinction.
Forest ecosystems help to enrich the soil. When trees are lost, the soil is left to the elements and will soon lose its nutrients. Soil becomes less fertile, making it less likely for plants to be able to thrive in the future. Without trees, soil erosion causes much of the world’s arable land to be lost, and floods are more common.
Forests have the unique ability to absorb carbon dioxide and other harmful pollutants. When we cut down trees, there are fewer trees to absorb greenhouse gases. Carbon is released back into the environment, leading to climate change. Deforestation also leads to disruption of natural water cycles. Trees help to regulate the balance of water between the ground and the atmosphere, as well as filter drinking water. Fewer trees mean less rain and more water flowing away from an area. 4
As consumers, we play a large role in the rapid increase of deforestation. By taking a closer look at the products we buy and the food we consume, we can slow down this process by choosing sustainably sourced products whenever possible.
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