Forest area, global

Keenan R, Reams G, Achard F, Freitas J, Grainger A, Lindquist E. Dynamics of global forest area results from the FAO Global Forest Resources Assessment. Forest Ecology and Management, 2015. 352 pp. 9-20. doi.org/10.1016/j.foreco.2015.06.014... 

Globally, it is estimated that there is 3870 million ha of forests (30 % of the Earth s land area), of which 95 % is natural or semi-natural (Table 1.1). At the present time, in most developed countries, the forest area is increasing and this is likely to continue given the present rates of harvesting. However, in tropical parts of the world, the forest area continues to decline, giving rise to serious concerns. It is estimated that between 1990 and 2000, there was a loss of 9.4 million ha per annum of forest worldwide (an annual deforestation rate of 14.6 million ha and an increase in forest area of 5.2 million ha per year Table 1.2). The only way to reverse this trend is to place sufficient economic value on forest resources, with incentives to encourage sustainable forest management. 

The biosphere is a major contributor to the atmosphere of heavier hydrocarbons. Fritz Went (8, 9), who first recognized the global extent of smog, pointed out the general importance of natural emissions from vegetation. He estimated that sources in the biosphere annually emit between 170 X 10 and 10 tons of hydrocarbon material to the atmosphere. Went also observed that these materials are mainly in the terpene class and that, because they are photochemically reactive, these materials are polymerized in atmospheric photochemical reactions to form an organic aerosol. He attributes the blue haze found in many forested areas to the optical effects of this aerosol. 

The earth s forests and jungles play a crucial role in maintaining the balance of gases in the atmosphere, removing CO2 and supplying O2. The massive destruction, for economic reasons, of heavily forested areas such as the Amazon rain forest in South America is cited as another long-term contributor to global environmental problems. Worldwide, more than 3 million square miles of once-forested land is now barren for some reason at least 60% of this land is now unused. 

In 2000 at the Netherlands, global warming talks broke down over carbon accounting. The United States wished to use its forest area to offsetting some carbon emissions. 

Green plants also release substantial quantities of isoprene (2) as well as monoterpenoid hydrocarbons such as a-pinene (3), myrcene (4), and limonene (5). These compounds contribute significantly to atmospheric organic concentrations in remote or forested areas (Altshuller, 1983 Hutte et al., 1984). It has been estimated that the global output of these substances may equal about 28% of the annual output of methane (Rasmussen and Went, 1965). 

Malaysia and Indonesia, located at the Southeast Asia region, are currently the two major players in the pahn oil market. Together, both countries account to more than 80 % of the global palm oil production. It is also a coincidence that both countries have been identified as the world s biodiversity hotspots, which harbor high numbers of indigenous and endemic species, which mostly inhabit the forests (Sodhi et al. 2004 Peh et al. 2006). Therefore, the excessive expansion of forest areas in Southeast Asia for oil palm activities seems the greatest threat to biodiversity (Noda et al. 2005 Donald 2004). 

The forests of Earth are multi-faceted and constitute vital ecosystems. With their 39 Mio km they cover about one-quarter of the land area worldwide. About half of the global forest area is shared by five countries - Russia, Brazil, Canada, USA and China. This ought to be considered with regard to forestry and timber strategies, when it comes to third-party certification with respect to sustainable management. Per annum, still 130,000 km of forests are cleared -which is more than the entire forest area of Germany. This contrasts with an increase in the forest area in other regions by 57,000 km. However, this mostly does not concern real forest, but plantations, mainly in the southern hemisphere. 

Even though Europe only has 5% of the global forest area, it produces nearly 30% of all wood products worldwide due to its large stocks of wood, efficient manufacturing technologies and a high rate in net product. 

In the Table 16.3, it can be observed that the barren land in Indonesia was increased from 9.3 Mha in 1980 to 13.3 Mha in 2005. Surprisingly, it was found that these lands were from the forest areas of Sumatra and Kalimantan. The fact is that these lands were occupied by local farmers for their agriculture and later, they were abandoned due to soil infertility, as reported by the Global Assessment of Human-Induced Soil Degradation (Wicke et al., 2008). 

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