论文部分内容阅读
以黔中黄壤坡耕地氮磷流失长期定位监测基地为平台,于2008—2012年连续5 a进行观测,研究玉米-油菜种植模式下,6种管理措施对黄壤坡耕地地表径流、径流氮输出的控制效果。结果表明:黄壤坡耕地产流系数为15.1%~20.1%,平均18.1%;氮肥流失系数为0.81%~1.34%,平均0.99%;径流氮输出以颗粒态氮所占TN比例46.9%最高,可溶性总氮流失以硝态氮为主,占TN流失的31.1%。优化施肥+横坡垄作+秸秆覆盖+等高植物篱的耕作管理措施截流效果、氮输出控制效果最佳,产流量较CK减少25%;氮肥流失系数最小,为0.81%;TN平均输出总量最小,为4.63kg·hm-2。顺坡常规耕作条件下,优化施肥与常规施肥径流量相当,TN输出量减少23.2%;优化施肥条件下,横坡垄作较顺坡常规耕作径流量减少6.7%,TN输出量减少7.3%;优化施肥+横坡垄作条件下,秸秆覆盖较无秸秆覆盖径流量减少4.8%,TN输出量减少3.4%;秸秆覆盖+等高植物篱较秸秆覆盖径流量减少11.6%,TN输出量减少6.8%。横坡垄作、优化施肥、秸秆覆盖、等高植物篱是控制黄壤坡耕地地表径流、径流中氮输出的有效措施。
Based on the long-term monitoring base of nitrogen and phosphorus loss on the yellow soil in the middle part of the Yellow River in Guizhou Province, the continuous monitoring and monitoring base was used as a platform in 2008 to 2012 for 5 consecutive days to observe the effects of six management measures on the runoff, Control effect. The results showed that the runoff coefficient of arable land in yellow soil was 15.1% ~ 20.1% with an average of 18.1%, the coefficient of nitrogen loss was 0.81% ~ 1.34% with an average of 0.99%. The output of runoff nitrogen was the highest with 46.9% The total nitrogen loss is dominated by nitrate nitrogen, accounting for 31.1% of the loss of TN. Optimum fertilization + cropping cover + contour hedgerows tillage management measures River closure effect, nitrogen output control effect is the best, the flow rate reduced by 25% compared with CK; The minimum nitrogen loss coefficient was 0.81%; TN average output volume The minimum is 4.63 kg · hm-2. Under the condition of conventional tillage, the optimal fertilization was equivalent to conventional fertilization and the TN output was reduced by 23.2%. Under the condition of optimized fertilization, the runoff decreased by 6.7% and the TN output decreased by 7.3% Under the condition of fertilization and horizontal slope ridge, the runoff of straw mulching and no straw mulching decreased by 4.8% and TN output by 3.4% respectively. The straw mulch + contour hedgerow reduced the runoff by 11.6% and the TN output by 6.8%. Landscaping, optimized fertilization, straw mulching and contour hedgerows are effective measures to control surface runoff and runoff nitrogen in yellow soil slopes.