Abstract:

In order to study the effect of intensive cropland use change on regional agricultural economy, ecological and environmental conditions in ecological fragile area, it is necessary to use comprehensive method to quantify agricultural inputs, outputs, and the ratio of output to input. Yanchi County in Ningxia was selected as a case area, which is located in typical farming-pastoral ecotone, and emergy analysis was used to study the changes of labor input, agricultural material input, cropland output, and the ratio of output to input of the cropland during 2001-2008. It was found that the labor input per unit area showed a fluctuating downward trend, but the agricultural material input per unit area increased in volatility with the change of cropland area; output per unit area fluctuated and the ratio of output to input decreased fluctuately, which was affected by labor input, agricultural material input, and precipitation. The results suggested that simply focusing on increasing agricultural investment and expansion of cropland area, while neglecting educated labor input and local ecological conditions after ecological restoration, might affect cropland productivity and resulted in increase of agricultural non-point source pollution risks.