There are numerous threats to the land and that which depends on it:
1 Deforestation and wildfires.
2 Excessive farming ruining the soil.
3 Biodiversity.
Deforestation and wildfires
Forests play a vital role in maintaining the balance of the Earth’s ecosystems. They provide habitat for more than half of all terrestrial species, help filter pollutants out of the air and water, and prevent soil erosion. Rainforests also provide essential hydrological (water-related) services. For example, they tend to result in higher dry season streamflow and river levels, since forests slow down the rate of water or rain run-off, and help it enter into the aquifer. Without a tree cover, the water tends to run off quickly into the streams and rivers, often taking a lot of topsoil with it. Forests also help the regional climate as they cycle water to the interior of a continent. The shrinking of the Amazon Rainforest reduces regional rainfall, which in turn threatens the health of the remaining forest and of the agricultural land in Southern Brazil. This also results in an increased fire risk.
Forests and their soils also play a critical role in the global carbon cycle. The level of CO2 in the atmosphere depends on the distribution or exchange of carbon between different “carbon pools” as part of the carbon cycle. Forests and their soils are major carbon pools, as are oceans, agricultural soils, other vegetation, and wood products: the carbon stored in the woody part of trees and shrubs (known as “biomass”) and soils is about 50% more than that stored in the atmosphere.
Trees continuously exchange CO2 with the atmosphere. The release of CO2 into the air is due both to natural processes (respiration of trees at night and the decomposition of organic matter) and human processes (removal or destruction of trees). Similarly, CO2 is removed from the atmosphere by the action of photosynthesis, which results in carbon being integrated into the organic molecules used by plants, including the woody biomass of trees. Thus forests play a major role in regulating global temperatures by absorbing heat-trapping carbon dioxide from the atmosphere, and storing it in the form of wood and vegetation – a process referred to as “carbon sequestration”.
Unfortunately, the global benefits provided by trees are being threatened by deforestation and forest degradation. ‘Deforestation’ as a shorthand for tree loss.Forest ‘degradation’ happens when the forest gets degraded, for example due to unsustainable logging practices which remove the most valuable species, or artesanal charcoal production in which only a few trees are harvested. The Earth loses more than 18 million acres of forestland every year—an area larger than Ireland—according to the United Nations Environment Programme (UNEP).
Deforestation is a major cause of global warming. When trees are burned, their stored carbon is released back into the atmosphere. As a result, tropical deforestation (including forest degradation) is responsible for about 12-15 percent of total annual global warming emissions according to the most recent estimates released for the climate change meeting in Copenhagen. Globally, some 10 million hectares of forests are lost annually, an area larger than Portugal.