2Bormann F,Likens G,Fisher D,et al. Nutrient loss ac- celerated by clear-cutting of a forest ecosystemFJ. Sci- ence, 1968,59:882-884.
3Hall D O, Rosillo Calle F,Williams R H, et al. Bio- mass for energy: supply prospects [M]. Washington DC : Island Press, 1993 : 593-651.
4Alexander S, Schneider S, Lagerquist K. Ecosystem services: interaction of climate and life [M].//Daily G. Nature Services: societal dependence on natural eeo systems[M]. Washington DC: Island Press, 1997:71 92.
5Pimentel D, Harvey C, Resosudarmo P, et al. Environ- mental and economic costs of soil erosion and conser- vation benefits[J]. Science, 1995,267 : 1117-1123.
