Spatio-temporal difference analysis of cultivated land use intensity based on emergy in the Poyang Lake Eco-economic Zone of China

Taking the emergy requirements of the five input indexes as the foundation, this paper analyzes the total temporal and spatial changes in cultivated land use intensity in the Poyang Lake Eco-economic Zone from 2000 to 2010. The results are obtained as follows: (1) Over a period of 10 years, the cultivated land use intensity has increased exponentially in the Poyang Lake Eco-economic Zone; agricultural machinery intensity has been the largest proportion of the total inputs, comprising more than 99.50% and increasing year by year, which indicates that agricultural mechanization is a basic trend in agricultural development in the Poyang Lake Eco-economic Zone. (2) The total number of counties belonging to the moderate- and low- intensity cultivated land use categories is the largest, while the number of counties belonging to the high-intensity cultivated land use and extensive cultivated land use categories is the smallest. (3) This zone can be divided into five areas: an eastern area of high-intensity cultivated land use, a central and eastern area of low-intensity cultivated land use, a central area of low-intensity cultivated land use, a southern area of moderate-intensity cultivated land use, and a northern area of moderate-intensity cultivated land use. (4) The counties which had a coordinated development between cultivated land use intensity and their socio-economic development level increase year by year, and the socio-economic development level had increasingly obvious effects on the cultivated land use intensity. Finally, this paper presents suggestions for the development of cultivated land use intensity in the Poyang Lake Eco-economic Zone, especially for different levels of intensity among counties.