Methodology for impact assessment of regional cultivated land resources change based on 3S technology

As there has been no generally accepted assessing indicator system on the impact of regional cultivated land change, this research explored three different kinds of evaluation indicator systems of regional cultivated land, which include cultivated land productive capacity indicators, cultivated land quality indicators and cultivated land natural grading and utilizing grading indicators, and three kinds of effect evaluation model of cultivated land resource change were established by using 3S technique. With the traditional method taking grain yield per hectare as an indicator, four assessment methods were created. And it analyzed the differences among four assessment methods in theory, characteristic and practicability. Taking North-eastern China as study case, the impact of cultivated land change on its grain production capacity was analyzed by the third method during the period of 1993 to 2003. Moreover, this paper proposed the impact assessment of crop planting structure and crop varieties on grain productivity. The results can provide useful information for the research related.