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Peter G. Ashton James B. Pickens Coryell Ohlander Bruce Benninghoff 《Journal of the American Water Resources Association》1980,16(4):738-744
ABSTRACT: Decisionmaking associated with the Nation's 1.7 billion acres of forest and range land has become increasingly complicated because of the rise in competition for resource use and in the awareness of environmental and social effects. This system analysis approach uses four models to synthesize pertinent masses of information into measures of economic, environmental, and social impacts. The system results can be used to help evaluate alternative national programs. The models are:
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A database of global agricultural primary production has been constructed and used to estimate its energy content. The portion
of crops available for food and biofuel after postharvest losses was evaluated. The basic conditions for agriculture and plant
growth were studied, to ensure sustainable scenarios regarding use of residues. The available energy contents for the world
and EU27 was found to be 7,200–9,300 and 430 TWh, respectively, to be compared with food requirements of 7,100 and 530 TWh.
Clearly, very little, or nothing, remains for biofuel from agricultural primary crops. However, by using residues and bioorganic
waste, it was found that biofuel production could theoretically replace one-fourth of the global consumption of fossil fuels
for transport. The expansion potential for global agriculture is limited by availability of land, water, and energy. A future
decrease in supply of fossil energy and ongoing land degradation will thus cause difficulties for increased biofuel production
from agriculture. 相似文献
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