摘要
在中国,氮肥的过量施用和作物对氮素回收率的降低造成了农业非点源污染的加重。不同的区域和农作物中氮肥的施用量变化很大,这取决于经济发展程度。比如,在东部地区和对经济作物的氮肥使用量要高于西部地区和谷类作物。甚至,在富裕地区,氮肥的施用量要远远高于中国科学院推荐的施肥量。要成功解决环境保护和作物高产,中国必须形成相应的农业政策鼓励经济发达地区的农民减少氮肥施用量,并且对于小尺度的农田系统和正在扩大的经济作物种植给出常规施肥建议。
Excessive nitrogen (N) fertilization and decreasing N recovery rates by crops have caused dramatic increases in nonpoint source pollution from agriculture in China. The rate of N fertilization across the country varies widely among regions and crops, depending on the stage of economic development.For example,N application rates in the eastern regions and on cash crops are far higher than in western regions of the country and on cereal crops.Moreover,N application rates in wealthier regions are higher than recommended by the Chinese Academy of Sciences.To successfully achieve environmental protection as well as high crop yields,China must formulate relevant agricultural policies to encourage farmers in economically developed areas to reduce their N fertilization rate while also issuing conventional fertilization recommendations for small-scale farming systems and the expanding cultivation of cash crops.
