When we look at a forest, it seems so alien, strange and remote from human affairs. Will human lives be better off if all forests are wiped out from the face of the Earth? Absolutely not. Contrary to what many of us think, forests are intimately connected with human welfare in myriad ways. Today, we shall dwell on one strand of this connection: Forests in relation to human health.
Forests impact human health
There are several ways in which forests affect human health. In today’s column, let’s discuss just a few of them.
Improvement of human health: scientific research has clearly shown that exposure to forests can reduce stress levels, help us recover from fatigue, and improve our overall mood. In fact, Japanese use a term for this effect, “forest bathing.”
Enhancement of physical health: spending time in forests improves physical health, reduces the levels of stress hormone cortisol, and helps boost our immune system, helping us ward off diseases better.
Provision of oxygen: forest trees (and phytoplankton in the oceans) provide oxygen for us (liberation of oxygen linked to carbon sequestration).
Provision of clean water: forests purify water and provide us clean water.
Mitigation of climate change: forest trees mitigate the effects of climate change. They absorb CO2 during photosynthesis, thus sequestering carbon and reducing the greenhouse effect (trees also absorb pollutants such as sulfur dioxide and carbon monoxide).
Besides the aforementioned positive impacts, forests also check soil erosion, control floods and regulate climate and disease transmission. It’s now known that forest degradation is linked to the rise in infectious diseases. There is definitive scientific evidence showing that many diseases such as malaria are more rampant in areas with high deforestation.
Higher disease outbreaks in deforested areas
In a news report in The Guardian (Mar 24, 2021), it’s said that outbreaks of infectious diseases are more likely in deforested areas. It’s quite possible that epidemics will likely increase as biodiversity declines. Land-use change precipitates the emergence of zoonotic viruses e.g., Covid-19 and vector-borne diseases e.g., malaria. The authors of the study cited in this newspaper said that diseases are filtered and blocked by a wide range of predators and habitats in a robust and biodiverse forest. When it is replaced by a palm oil plantation or soy fields or fields of eucalyptus, the specialist species die off, leaving only generalist species such as rats and mosquitoes to thrive and spread pathogens. This leads to breakdown of natural disease regulation. Clearly, forests play a critical role in regulation of human and non-human diseases.
There is also a growing body of evidence that suggests that viruses are more likely to jump to humans or animals if they live in or near human-disturbed forests (for example, as reservoirs in wild bats).
Unless we stop or mitigate deforestation rapidly, the next outbreak worse than COVID-19 or a disease as nasty as malaria is going to run wild in the world’s regions with abundance of deforested areas and monoculture plantations such as palm oil plantations.
Drivers of deforestation
If forests are so important to us, why are they disappearing all over the world so fast? There is now rapid forest loss, forest fragmentation and forest degradation. What are the main drivers of deforestation? The major causes include:
Conversion of forests: conversion of forests into other land uses such as pulp, palm oil and soy plantations, pastures, settlements, roads, and developmental infrastructure.
Forest fires: fires from both natural and artificial causes have adverse impacts on forest health, biodiversity and regenerative capacity.
Logging: illegal and unsustainable logging practices destroy the natural forest resources as well as wildlife.
Firewood harvesting: overharvesting of trees and other forest plants for domestic use or charcoal trade leads to extensive damage of forests.
Mining: mining operations exert adverse pressure on forests and freshwater ecosystems.
Climate change: forest loss is both a cause and effect of climate change.
Conserving our forests
If we know the reasons for deforestation and realize the benefits of forests, why are we not conserving them? There is no easy answer. There is an intricate interplay of science, politics, human greed, and corporate interests that make us unable to prevent deforestation and initiate conservation efforts.
Nonetheless, let’s discuss some possible steps for forest conservation.
Some of these could be:
Regulated & planned felling of trees: cutting could be regulated by using methods such as clear cutting, selective cutting and shelterwood cutting.
Control of forest fires: latest techniques of firefighting including the use of water sprays, fire retardant chemicals and creating fire lanes around the periphery of the fire could be used to check forest fires.
Reforestation & afforestation: denuded areas of the forest must be reforested as soon as possible, as also areas destroyed by fires or mining activities. In rough terrain, aerial seeding may be used for reforestation purposes. In addition, afforestation programmes could be initiated to increase the forest cover. For this, proper selection of trees suited to the local conditions must be done. And, utmost care has to be given in the initial phase of the program.
Urban afforestation: the Miyawaki method
The Miyawaki method is a Japanese method for creating urban forests in a short period of time. Several states in India including Telangana have already adopted this method. This method helps build dense, native forests in a short period. It helps to create a forest in just 20-30 years (instead of the traditional period of 200-300 years). This method uses only native trees which are planted as close as possible in the same area. The process usually involves the identification of native trees which are divided into 4 layers: shrub, sub-tree, tree, and canopy, analysis of soil quality, selection of biomass with rich nutrients and high water-retention capacity, mixing the soil with the biomass, creating a mound with the soil and planting the seeds in a high density and then covering the ground with a thick layer of mulch
If humanity has to have a future in the climate change scenario, we must take our forests very seriously. In denuded areas, reforestation projects must be initiated on a war footing. In addition, we must carry out afforestation programs to enhance the forest cover. And, we may contemplate creating urban forest quickly through innovative methods such as the Miyawaki method.
(The views expressed is personal)