宁夏东部风沙区人工草地亚系统的能值分析

Emergy analysis of artificial grassland subsystem of Wind-Blown sand area in Eastern Ningxia

针对宁夏东部风沙区草地农业生态系统环境脆弱,生产力低的问题,以盐池县四墩子村复合为研究对象,应用生态系统能值理论与分析方法,通过建立能值指标体系,对2002—2009年人工草地亚系统进行了分析.结果表明,人工草地亚系统多年平均产出与投入比值为1.55,并且逐年增加,系统整体功能好,运转效率较高,能值回报率高,产品在市场上的价格具有绝对的竞争力.净能值产出率高,而环境负荷率相对较低,可持续发展指数为1.23到0.92,多年平均值为1.06,系统整体富有活力和发展潜力.最后结合当地的实际情况提出宁夏东部风沙区可持续发展的建议.

In view of the problem that the grassland ecosystem was fragile, and the productivity was low in the grassland farming ecosystem in eastern Ningxia, focusing on Sidunzi in Yanchi County, by setting up emergy index system, we compared and analysed the input and output status and each emergy index of the artificial subsystem. The results were as follows： annual ratio of output cost of artificial grassland subsystem was 1. 55 and increased yearly with fine integral system {unction, high operation efficiency, high return on emergy, and absolutely competitive price of the product. Emergy yield ratio was high while environmental loading ratio was low. The index of sustainable development was 1.23--0.92 and average value in many years was 1.06, which showed artificial grassland subsystem was energetic and potential. With combination of the local practical status, then put forward the advice about sustainable development of wind-blown sand area in eastern Ningxia.