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植被在坡面的位置对坡面保持水土的作用是不同的。动态监测澄江抚仙湖一级支流尖山河小流域坡耕地降雨-径流过程及水土流失量,研究草带措施对云南红壤坡耕地产流产沙和氮磷迁移的削减作用。结果表明:草带调控处理下雨季降雨量、总产流次数、径流深和土壤侵蚀量较原状坡面明显减少,次降雨下,宽草带的径流控制率和土壤侵蚀控制率分别为79.19%和64.55%,窄草带的径流控制率和土壤侵蚀控制率分别为85.15%和73.77%,坡耕地土壤侵蚀量变异系数>径流深变异系数>降雨量变异系数,原状坡面变异系数间增幅差异为31.42%,宽草带调控措施作用下变异系数间增幅差异为20.37%,窄草带调控措施作用下变异系数间增幅差异为19.11%,窄草带对坡耕地径流和泥沙的调控能力更强;宽草带和窄草带2种草带作用下,径流氮磷迁移浓度差异不显著,较原状坡面相比,草带措施明显控制氮磷迁移通量,径流总氮迁移通量控制率分别为81.23%和81.68%,铵态氮迁移通量控制率为78.25%和59.50%,总磷迁移通量控制率为71.36%和82.03%;径流泥沙速效养分含量明显增加,较原状坡面相比,草带措施能明显控制径流泥沙氮磷迁移通量,且径流泥沙氮磷迁移控制率较径流氮磷迁移控制率高,径流泥沙全氮迁移通量控制率为98.43%和94.30%,碱解氮迁移通量控制率为98.43%和93.10%,全磷迁移通量控制率为96.43%和89.77%,速效磷迁移通量控制率为90.34%和57.43%。
Vegetation on the slope of the slope to maintain the role of soil and water are different. The rainfall-runoff process and soil erosion of sloping farmland in Jianshanhe watershed, a tributary of Fuxian Lake, are dynamically monitored. The effects of grassbelt measures on reducing runoff and sediment production and nitrogen and phosphorus migration on sloping farmlands of red soil in Yunnan Province are studied. The results showed that under the rainfall control, the runoff control rate and soil erosion control rate of broad-leaved grass belt were 79.19% And 64.55% respectively. The control rates of runoff and soil erosion of narrow grass strip were 85.15% and 73.77%, respectively. The coefficient of variation of soil erosion, the coefficient of variation of runoff depth, the coefficient of variation of rainfall and the coefficient of variation of undisturbed slope Which is 31.42%. The difference of variation coefficient of variation coefficient is 20.37% under the action of wide-range regulation, 19.11% of the variation difference under the regulation of narrow-range regulation, and the narrow regulation of sloping runoff and sediment is more Under the action of two kinds of grass belts, the difference of runoff nitrogen and phosphorus concentrations was not significant. Compared with the original slope, the grass belt measures significantly controlled the flux of nitrogen and phosphorus and the flux of total nitrogen flux The rates of total phosphorus fluxes control were 71.36% and 82.03%, respectively. The contents of available nutrients in runoff sediment obviously increased compared with those of the original slope Compared with the surface, grass banding measures can be significantly controlled The results showed that the control rate of nitrogen and phosphorus migration of runoff and sediment was higher than that of runoff nitrogen and phosphorus migration control. The control rates of total nitrogen migration flux of runoff and sediment were 98.43% and 94.30% The control rates were 98.43% and 93.10%, the control rates of total phosphorus flux were 96.43% and 89.77%, and the control rates of available phosphorus flux were 90.34% and 57.43%.