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坡耕地水土流失已成为小浪底库区生态环境和农业可持续性发展所面临的一个重大问题。通过饱和入渗和模拟降雨试验,对不同退耕利用方式(撂荒坡地、造林幼林地、林草间作、农林间作)和传统坡耕地利用方式(坡耕地翻耕休闲、坡耕地翻耕后种植玉米)入渗规律与产流、产沙特征做了研究。结果表明:(1)退耕后坡面饱和入渗率均高于传统方式,其四种方式平均饱和入渗率是传统利用方式的1.48倍;撂荒坡地的饱和入渗率最高;同一坡面,坡底饱和入渗率高于坡中、上部。(2)初始产流时间,撂荒坡地、造林幼林地、林草间作、农林间作分别比翻耕种玉米延迟26.16min、14.89min、13.48min、6.01min,两种传统方式差别不大。持续产流时间退耕方式也长于传统方式。(3)传统方式径流总量是上述四种退耕方式的2~5倍,平均产流速率明显高于退耕方式;产沙总量是退耕方式的3~50倍左右,平均产沙速度是其的1.72~9.4倍;产沙、产流总量和与产流降雨历时密切相关。
Soil and water loss in sloping farmland has become a major issue facing the ecological environment and sustainable development of agriculture in Xiaolangdi Reservoir Area. Through saturated infiltration and simulated rainfall experiments, the different land use types (fallow slope land, afforestation grassland, forest and grass intercropping, agro-forestry intercropping) Infiltration law and runoff, sand production characteristics were studied. The results show that: (1) The saturated infiltration rate of slope after returning farmland is higher than the traditional way, the average saturated infiltration rate of four ways is 1.48 times that of the traditional way; The saturated infiltration rate at the bottom of the slope is higher than that in the upper part of the slope. (2) The initial runoff time, fallow slope, afforestation grassland, intercropping forest and grassland and intercropping with agro-forestry were respectively 26.16min, 14.89min, 13.48min and 6.01min later than that of tillage maize. There was little difference between the two traditional ways. Continuous production runoff time is also longer than the traditional way. (3) The total amount of runoff in the traditional method is 2 ~ 5 times that of the above four kinds of returning farmland, and the average rate of runoff is obviously higher than that of returning farmland; the total amount of sediment is about 3 ~ 50 times of that of returning farmland, and the average sediment yield is Of 1.72 to 9.4 times. The total amount of sand production and runoff is closely related to rainfall runoff.