Analysis of Agricultural Cultivation Based on a New Landscape Expansion Index: A Case Study in Guishui River Basin, China

摘要

Agricultural cultivation?is always a global?hot topic in agricultural and environmental sciences. The process of agricultural cultivation in Guishui river basin, China from 1978 to 2009 was studied based on landscape ecology?principles with six Landsat images. A new landscape expansion index (LEI) was proposed to quantitatively indicate expansion size of farmland patches, and identify their spatial?expansion patterns (adjacent expansion pattern and external expansion pattern). The primary conclusions were as follows. First, the expansion patterns of most expanding farmland patches were adjacent expansion pattern for approximately 30 years, whereas the number of adjacent and external expansion pattern patches fluctuated. Second, the values of LEI primarily distributed in the interval of (-1,-0.8), demonstrating that the spatial expansion pattern of farmland patches were largely adjacent expansion pattern on a small scale. Third, values of LEI tended to decrease overall as the expansion scale of farmland was gradually reduced.