Friday, August 31, 2012

World Forest Area Still on the Decline

Forests provide many important goods, such as timber and paper. They also supply essential services—for example, they filter water, control water runoff, protect soil, regulate climate, cycle and store nutrients, and provide habitat for countless animal species and space for recreation.

Forests cover 31 percent of the world’s land surface, just over 4 billion hectares. (One hectare = 2.47 acres.) This is down from the pre-industrial area of 5.9 billion hectares. According to data from the U.N. Food and Agriculture Organization, deforestation was at its highest rate in the 1990s, when each year the world lost on average 16 million hectares of forest—roughly the size of the state of Michigan. At the same time, forest area expanded in some places, either through planting or natural processes, bringing the global net loss of forest to 8.3 million hectares per year. In the first decade of this century, the rate of deforestation was slightly lower, but still, a disturbingly high 13 million hectares were destroyed annually. As forest expansion remained stable, the global net forest loss between 2000 and 2010 was 5.2 million hectares per year.

Global rates of deforestation do not capture the full damage done to the world’s forests. Forest degradation from selective logging, road construction, climate change, and other means compromises the health of remaining forests. Each year the world has less forested area, and the forests that remain are of lower quality. For example, replacing natural old-growth forests with a monoculture of an exotic species greatly reduces biodiversity.

The spread of planted forests has been accelerating, rising from an expansion of 3.7 million hectares annually in the 1990s to 4.9 million hectares annually the following decade. Planted forests now cover some 264 million hectares, comprising nearly 7 percent of total forest area. Plantations now have the potential to produce an estimated 1.2 billion cubic meters of industrial wood each year, about two thirds of current global wood production. Where forests have already been cleared, plantations can alleviate the pressure on standing forests.

Forests are primarily threatened by land clearing for agriculture and pasture and by harvesting wood for fuel or industrial uses. In Brazil—which has lost 55 million hectares since 1990, an area three fourths the size of Texas—land clearing for farms and ranches is the big driver. Home to the Amazon rainforest, Brazil contains 13 percent of the world’s forested area, second only to Russia’s 20 percent. Between 2000 and 2010, Brazil lost 2.6 million hectares of forest each year, more than any other country. Brazil is trying to reduce deforestation rates 80 percent from the 1996–2005 average by 2020 and has in fact seen a large drop in deforestation in recent years. But rising beef, corn, and soybean prices are likely to pressure the government to weaken its forest protection, further threatening the world’s largest rainforest. More