苏南太湖流域水稻氮肥利用率及氮肥淋洗量研究

在苏南太湖流域，对不同氮肥施用水平下水稻的产量，氮肥利用率及氮肥水环境损失进行了研究。结果表明，在３５０ｋｇ／ｈｍ＾２的高氮肥施用水平下，水稻产量已经下降，植株发生氮素“奢侈”吸收，氮肥利用率下降，氮的淋洗量迅速增加。在以上研究结果的基础上，利用环境经济学的Ｃｏａｓｅ原理和农业技术经济学的边际收益分析原理求得，２２１．５－２６１．４ｋｇ／ｈｍ＾２Ｎ为苏南太湖流域目前生产条件下，水稻兼顾生产，生态和

Rice Nitrogen Utilization Efficiency and Nitrogen Leaching Amount in Taihu Lake Watershed of South Jiangsu Province

In Tai Lake Watershed of south Jiangsu province the studies on rice yield, nitrogen utilization efficiency, nitrogen leaching amount at different nitrogen fertilizer doze in paddy rice field were made. When nitrogen fertilizer application amount exceeds 350 kg/hm2, the rice yield began to decrease, so-called over abundant nitrogen absorption happens, and nitrogen utilization efficiency decreases, as well as nitrogen leaching amount increases rapidly. On the basis of above research, with the Coase Theory of Environmental Economics, the ecological agronomic and economic satisfactory nitrogen fertilizer doze for current production was obtained as 221. 5 ~ 261. 4 kg/hm2.