【摘要】 基于汛期次暴雨径流实验数据,研究了淮北地区不同作物植被类型下农田地表氮磷径流流失规律和特征。结果表明,作物植被类型差异对地表径流量、土壤侵蚀量、氮磷径流流失量影响的强弱顺序大致为裸地>玉米地>棉花地>黄豆地。作物叶面积指数应是导致不同作物植被类型下地表径流量和土壤侵蚀量差异明显的主要影响因素。而影响氮磷径流流失量的要素则与作物叶面积指数和地表径流量密切相关。对具有较高植被覆盖度的黄豆和棉花地而言,可溶性氮磷是农田氮磷径流流失的主要形式,而玉米地中颗粒态氮和可溶性磷分别是农田氮磷径流流失的主要形式。在当地汛期种植黄豆、棉花等高叶面积指数的作物可有效减少氮磷地表径流流失,减缓农业面源污染带来的威胁。更多还原

【Abstract】 The laws and characteristics of nitrogen and phosphorus runoff losses from farmland surface for different crop vegetations in north part of the Huaihe River basin were analyzed according to the experimental data of each rainstorm event in flood season.The result shows that the runoff,soil erosion,nitrogen and phosphorus losses are significantly affected by crop vegetation type.The effect intensities for various crops is in the order of bare land>corn>cotton>soybean.The leaf area index is the main factor that makes the surface runoff and soil erosion of various crop vegetations significantly different.The factors affecting the losses of nitrogen and phosphorus are also closely related to the leaf area index and surface runoff.It is found that the dissolved nitrogen and dissolved phosphorus are the main forms of nitrogen and phosphorus losses for cotton and soybean,but the particulate nitrogen and dissolved phosphorus are the main forms of nitrogen and phosphorus losses for corn plot.Soybean and cotton plots reduce the surface losses of nitrogen and phosphorus.更多还原