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选取丹江口水库河南部分的最大入库河流老鹳河的支流蒿坪河小流域为研究对象,依托径流场等野外设施,系统开展了不同坡度和土地利用类型降雨径流特征的研究,研究结果表明:蒿坪河小流域降雨年度分布不均,暴雨集中型降雨产流量大,是产生非点源污染主要降雨类型。0°～5°耕地、5°～10°耕地、10°～15°耕地、栎林和果园平均径流系数分别为2.01%,2.98%,5.44%,16.47%和2.42%。陡坡地带栎林在降雨侵蚀力大于0.5的时候开始产流,以超渗方式为主;果园在降雨侵蚀力大于2.5的时候开始产流,以蓄满产流为主;耕地产流受人为影响显著,产流界限不容易确定,在暴雨集中型降雨条件下其产流以超渗方式为主。栎林和果园产流量与降雨侵蚀力均存在一定的线性相关性,R2分别为0.939和0.912。耕地由于受人为影响比较大,其产流与降雨侵蚀力关系波动较大。在暴雨集中型降雨条件下,坡度是影响产流的主要因素,10°～15°耕地产流和0°～5°,5°～10°差异性显著(P<0.05)。在小雨集中型降雨条件下,土壤结皮成为影响产流的主要因素。对大于10°的耕地,实施坡改梯工程,根据气象条件适时的锄地,有利于雨水的下渗,对于保持土壤水分、减少径流和农业非点源污染都有很重要的现实意义。
Taking the Artemisia river, a tributary of Laosheng River, the largest storied river in Henan part of the Danjiangkou Reservoir, as the research object, based on the outdoor facilities such as runoff field, the study of rainfall runoff characteristics of different slope and land use types was carried out. The results show that: The annual rainfall in the Hanpinghe small watershed is unevenly distributed, with a large rainfall-intensive rainfall runoff, which is the main type of rainfall that causes non-point source pollution. The average runoff coefficients of 0 ° ~ 5 ° cultivated land, 5 ° ~10 ° cultivated land, 10 ° ~ 15 ° cultivated land, oak forest and orchard were 2.01%, 2.98%, 5.44%, 16.47% and 2.42%, respectively. In the steep slopeland, the oak forest started to produce runoff when the rainfall erosive power was greater than 0.5, which was dominated by the hyperosmotic mode. When the rainfall erosivity exceeded 2.5, the orchard started to produce runoff, which was mainly filled with runoff. Significantly, the confluence of runoff can not be easily determined, and its runoff is dominated by ultra-permeation under concentrated rainfall conditions. Quercus variabilis and orchard output and rainfall erosive power there is a certain linear correlation, R2 were 0.939 and 0.912. Because cultivated land is greatly affected by human activities, the relationship between runoff and rainfall erosivity fluctuates greatly. Under the condition of rainstorm concentrated rainfall, the slope is the main factor affecting the runoff. The runoff at 10 ° ~ 15 ° was significantly different from that of 0 ° -5 ° and 5 ° -10 ° (P <0.05). Under the conditions of rain-concentrated rainfall, soil crust became the main factor affecting the runoff. For the cultivated land more than 10 °, it is very important to maintain the soil moisture, reduce the runoff and agricultural non-point source pollution by carrying out the slope to ladder project and timely hoeing according to the meteorological conditions.