[Impacts of cultivated land conversion on cultivated land productivity in China: prediction and analysis].

This paper simulated the spatial patterns of cultivated land in China under the future scenario by using the Dynamics of Land System (DLS) model, and then estimated the cultivated land productivity at the grid pixel dimensions based on the Estimation System of Land Production (ESLP). In addition, the spatial patterns of cultivated land productivity in each of China agro-ecological zones were analyzed. On this basis, this paper predicted the impacts of cultivated land conversion on the cultivated land production in China in 2000-2020, and identified the major affecting factors on the cultivated land production. The research results indicated that the impact of improving the cultivated land productivity on the cultivated land production would be wunch more remarkable than that from the magnitude of cultivated land conversion in regions where there were high potential to imrprove the cultivated land productivity. However, in the regions with nearly no room to improve the productivity, cultivated land conversion would produce more apparent impacts on the total cultivated land production. In this sense, it was of significance for the national food security in China to adjust the cultivated land conversion to ensure the 0.12 billion hm2 of cultivated land, and to increase investment and improve management level to increase per unit grain yield.