Trees.
as..food..
cover...
as a CO 2 sink......
ect
earth-policy.org
Reed Funk, professor of plant biology at Rutgers University, believes the vast areas of deforested land can be used to grow trillions of genetically improved trees for food, mostly nuts, and for fuel. Funk sees nuts used to supplement meat as a source of high-quality protein in developing-country diets. He also sees trees grown on this deforested land, much of it now wasteland, being used for conversion into ethanol for automotive fuel. 10
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Five countries account for two thirds of tree plantations. China, which has little original forest remaining, is the largest, with Russia and the United States following. India and Japan are fourth and fifth. Brazil is further back, but is expanding fast. As tree farming expands, it is shifting geographically to the moist tropics. In contrast to grain yields, which tend to rise with distance from the equator and the longer summer growing days, tree plantation yields rise with proximity to the equator and year-round growing conditions. 15
In eastern Canada, the average hectare of forest plantation produces 4 cubic meters per year. In the southeastern United States, where U.S. plantations are concentrated, the yield is 10 cubic meters. But in Indonesia, it is 25 cubic meters, and in Brazil, newer plantations may be close to 30 cubic meters. While corn yields in the United States are nearly triple those in Brazil, timber yields are the reverse, favoring Brazil by nearly 3 to 1. To satisfy a given demand for wood, Brazil requires only one third as much land as the United States, which helps explain why growth in pulp capacity is now concentrated in equatorial regions. 16
see photo
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