Abstract: Based on the 1971-2004 agricultural data of East China and the 1961-2004 daily mean temperature data from 26 local meteorological stations, this paper analyzed the relationships between farming system and effective accumulated temperature in East China. The results showed that in 1961-2004, the date of daily mean temperature rising steadily over 10 ℃ came earlier, while that dropping steadily below 10 ℃ was later, resulting in a steadily increased effective accumulated temperature. The multiple cropping indices in Zhejiang, Shanghai and Jiangsu decreased with increasing accumulated temperature, and the correlation coefficients were -0.605, -0.582, -0.615 (n=34), respectively; while the indices in Shandong and Anhui were in adverse, with the correlation coefficients of 0.655 and 0.441 (n=34), respectively. The grain yield per unit area increased with increasing accumulated temperature, and the correlation coefficients for Fujian, Jiangxi, Zhejiang, Shanghai, Anhui, Jiangsu and Shandong were 0.602, 0.370, 0.454, 0.761, 0.518, 0.621 and 0.489 (n=34), respectively. The planting area of grain crops decreased, while that of vegetables, melons, economic forests and oil plants increased with increasing accumulated temperature. The consumptions of fertilizers and pesticides also increased with increasing accumulated temperature.

Key words: Cotton, Nitrogen management, Water management, Knowledge model