An Evaluation of Stability of Farmland Ecosystem Based on Processes in Hebei Plain

This paper aims at discussing the concept and connotation and evaluating index system of the stability of farmland ecosystem in Hebei Plain of China.First,based on the analysis of the research result of vulnerability in the field of ecosystem science,a concept of stability of farmland ecosystem which represents the characteristic of farmland ecosystem in Hebei Plain of China is formed.Then,the connotation about the stability of farmland ecosystem is probed.It is believed that the assessment index system of the farmland ecosystem stability includes four aspects of input-output process,yield formation process,soil ecological process and eco-environmental effect of farmland ecosystem and 22 concrete indices.Finally,the evaluating model of the stability of farmland ecosystem is built,and is applied to evaluate synthetically the status of stability of farmland ecosystem by taking Xiongxian county of Hebei as an example.It is found by validation that the stability of farmland ecosystem varies greatly,which presents a linear decreasing trend in 1995-1999 and wavy development in 2000-2005 with the greatest impact of input-output process.