磴口县农林复合生态系统农田子系统能流分析

Energy flow in the farmland subsystem in agroforestry ecosystem in Dengkou County

采用Odum能流分析理论以及主成分分析法,结合磴口县1992～2008年统计年鉴,选取有机能、无机能、能量总投入和总产出、产投比、能量循环指数和投能结构6个指标,对磴口县农林复合生态系统农田子系统的能流特征进行定性、定量分析。结果表明:该地区有机肥使用量逐年降低,而无机肥却在增加;该系统能量产出大于投入,产投比为:3.17:1,处于能量亏损状态,长期发展下去,系统会失调,甚至产生生态危机。从时间尺度上分析和探讨了农田子系统的能量流动,从而为促进磴口县农田子系统的可持续发展提供依据。

We adopted the energy flow analysis theory and principal components analytic method,used the Dengkou County Statistical Annual（1992~2008） and chose 6 indexes which are organic and inorganic energy,the energy total input and output,ratio of output to input and the energy cycle index to analyse energy flow characteristics of the farmland subsystem in agroforestry ecosystem in the Dengkou County.The results showed that the organic fertilizer use reduced year by year,but inorganic fertilizer was actually increasing;Energy input was greater than output,and the system was under the energy loss condition for a long time,it would engender the ecological crisis.In brief,we have analyzed and discussed the farmland subsystem on temporal scale,thus might to provide the basis for the Dengkou County farmland subsystem＇s sustainable development.