In 1935 there was only 1,757,000 hectares of forest, today this has increased by more than 150%.
Forest management has changed considerably over the last few centuries, with rapid changes from the 1980s onwards culminating in a practice now referred to as sustainable forest management.
The total biomass has decreased slightly since 1990 but biomass per unit area has increased. Forest ecosystems can be found in all regions capable of sustaining tree growth, at altitudes up to the tree line, except where natural fire frequency or other disturbance is too high, or where the environment has been altered by human activity. The latitudes 10° north and south of the equator are mostly covered in tropical rainforest, and the latitudes between 53°N and 67°N have boreal forest.
As a result, the net loss of forest area is less than the rate of deforestation and it too is decreasing: from 7.8 million hectares per year in the 1990s to 4.7 million hectares per year during 2010– 2020.
In absolute terms, the global forest area decreased by 178 million hectares between 1990 and 2020, which is an area about the size of Libya. ==Societal significance== Forests provide a diversity of ecosystem services including: converting carbon dioxide into oxygen and biomass.
More than 75% of these intact forests lie in three countries—the boreal forests of Russia and Canada and the rainforest of Brazil. According to FAO's Global Forest Resources Assessment 2020, an estimated 420 million hectares of forest has been lost worldwide through deforestation since 1990, but the rate of forest loss has declined substantially.
As a result, the net loss of forest area was reduced to 5.2 million hectares per year between 2000 and 2010, down from 8.3 million hectares annually in the 1990s.
The area of forest in protected areas globally has increased by 191 million ha since 1990, but the rate of annual increase slowed in 2010–2020. Smaller areas of woodland in cities may be managed as urban forestry, sometimes within public parks.
In 1997, the World Resources Institute recorded that only 20% of the world's original forests remained in large intact tracts of undisturbed forest.
However, the United States Forest Service estimates a net loss of about 2 million hectares (4,942,000 acres) between 1997 and 2020; this estimate includes conversion of forest land to other uses, including urban and suburban development, as well as afforestation and natural reversion of abandoned crop and pasture land to forest.
In the most recent five-year period (2015–2020), the annual rate of deforestation was estimated at 10 million hectares, down from 12 million hectares in 2010–2015. China instituted a ban on logging, beginning in 1998, due to the erosion and flooding that it caused.
As a result, the net loss of forest area was reduced to 5.2 million hectares per year between 2000 and 2010, down from 8.3 million hectares annually in the 1990s.
Much more forest land—about 40 percent of the total forest land base—is subject to varying degrees of protection through processes such as integrated land use planning or defined management areas such as certified forests. By December 2006, over 1,237,000 square kilometres of forest land in Canada (about half the global total) had been certified as being sustainably managed.
As a result, the net loss of forest area is less than the rate of deforestation and it too is decreasing: from 7.8 million hectares per year in the 1990s to 4.7 million hectares per year during 2010– 2020.
In the most recent five-year period (2015–2020), the annual rate of deforestation was estimated at 10 million hectares, down from 12 million hectares in 2010–2015. China instituted a ban on logging, beginning in 1998, due to the erosion and flooding that it caused.
As a result, the net loss of forest area was reduced to 5.2 million hectares per year between 2000 and 2010, down from 8.3 million hectares annually in the 1990s.
The area of forest in protected areas globally has increased by 191 million ha since 1990, but the rate of annual increase slowed in 2010–2020. Smaller areas of woodland in cities may be managed as urban forestry, sometimes within public parks.
second growth). Forests can also be classified more specifically based on the climate and the dominant tree species present, resulting in numerous different forest types (e.g., Ponderosa pine/Douglas-fir forest). The number of trees in the world, according to a 2015 estimate, is 3 trillion, of which 1.4 trillion are in the tropics or sub-tropics, 0.6 trillion in the temperate zones, and 0.7 trillion in the coniferous boreal forests.
In 2015, a study for Nature Climate Change showed that the trend has recently been reversed, leading to an "overall gain" in global biomass and forests.
However new forests are not completely equivalent to old growth forests in terms of species diversity, resilience and carbon capture. On 7 September 2015, the Food and Agriculture Organization of the United Nations released a new study stating that, over the last 25 years, the global deforestation rate has decreased by 50% due to improved management of forests and greater government protection. There is an estimated 726 million ha of forest in protected areas worldwide.
For example, a research from 2017, show that forests induce rainfall.
Using this definition FRA 2020 found that forests covered 4.06 billion hectares or approximately 31 percent of the global land area in 2020. Forests are the predominant terrestrial ecosystem of Earth, and are distributed around the globe.
As a result, the net loss of forest area is less than the rate of deforestation and it too is decreasing: from 7.8 million hectares per year in the 1990s to 4.7 million hectares per year during 2010– 2020.
In absolute terms, the global forest area decreased by 178 million hectares between 1990 and 2020, which is an area about the size of Libya. ==Societal significance== Forests provide a diversity of ecosystem services including: converting carbon dioxide into oxygen and biomass.
More than 75% of these intact forests lie in three countries—the boreal forests of Russia and Canada and the rainforest of Brazil. According to FAO's Global Forest Resources Assessment 2020, an estimated 420 million hectares of forest has been lost worldwide through deforestation since 1990, but the rate of forest loss has declined substantially.
However, the United States Forest Service estimates a net loss of about 2 million hectares (4,942,000 acres) between 1997 and 2020; this estimate includes conversion of forest land to other uses, including urban and suburban development, as well as afforestation and natural reversion of abandoned crop and pasture land to forest.
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