Research Of The Influence Of Different Slope Land Cover On Soil And Water Loss

In order to study the effect of straw mulching on soil erosion in different slope (5°?10°?15°) and different slope position (Straw were evenly spread in the area of the upper part?the middle part?the lower part of the district, the upper and middle parts of the district, the upper and lower parts of the district, the middle and lower parts of the district,the entire district), this research is mainly about how the straw mulching in different slope position affects the variation regular of soil water and sediment under the condition of a certain amount of rainfall intensity by rainfall stimulation.(1)With the increase of slope gradient, the time of the start of the runoff increased, that is, the higher the slope, the shorter the runoff time. Under the same slope, when 6.0 kg of dry weight of cornstalks spread evenly on the lower 1/3 of runoff plots, the starting runoff time is the longest, while the runoff time is the shortest when the lower part is not covered by cornstalk. And the time difference is small.(2)Straw mulch on the same slope has a positive correlation with the gradient of the straw cover. Under the same slope, runoff time increases over time, and eventually stabilizes.(3)Straw mulching on the same position, with the increase of slope, the erosion of the soil by the rain enhances, and the sediment yield increases. Slope as 15° slope of bare land, the total sediment yield are 5.4 times and 2.9 times than that of 5° slope and 10° slope's yield. Under the same slope, no matter what kind of the straw mulching on the slope position, the sediment yield will show an increasing trend after a reduction at first. Slope runoff and sediment concentration decreases with the duration of rainfall, and gradually stabilizes.(4)Under the same slope, compared with the bare land, sediment and runoff have different degrees of reduction on seven different slope positions of straw mulching. And when all the dry weight of 6.0kg of cornstalks cover the bottom of the runoff plots, the sediment and runoff yield is the most obvious. The sediment yield is only 3.4%?6.8% of the total yield of the bare land, the start runoff time delays. Production flow is only 31.2%?32.2% of the bare land's.The results show that the soil and water conservation benefit is obvious when the straw covers the lower part of the slope land, which provides a theoretical basis for guiding local farmers reasonable selection of plow position on slope lands and maximizing the use of straw to reduce soil erosion.