Limestone Soil Water And Soil Erosion Under Simulated Rainfall

In this paper, the Taihang Mountain limestone soil, indoor simulated rainfall experiments to study the different rainfall intensity, slope limestone soil slope erosion runoff and sediment process and test data obtained based on the physical and chemical properties of soil and artificial rainfall, combined with the universal soil loss equation RUSLE model and the previous sum up experience and explore the limestone soil erodibility K value determination method with rainfall intensity variation. The main conclusions obtained are as follows:(1) the slope dynamic runoff in other conditions the same, under different rainfall intensities increase with the increase of rainfall intensity of 100mm / h> 85mm / h> 60mm / h;(2) change of slope runoff with rainfall intensity, 100mm / h the runoff 540.97L-603.20L, 85mm / h runoff 445.68-528.95L The runoff 60mm / h 332.28L-354.52L;(3) Runoff sediment concentration change, the slope is 5°, runoff and sediment content increased with the increase of rainfall intensity, slope 10°, 15°, 20°, 25°, 85mm / h, and100mm / h rainfall intensity, runoff sediment concentration is very close, and were greater than 60mm / h rainfall intensity, runoff and sediment content;(4) slope cumulative production and sand total changes with rainfall intensity, a total of 100mm / h and the sediment yield 9293.57g-13670.34g 85mm / h, total sediment yield is 7201.51g-11855.19g, 60mm / hThe total sediment yield 5273.98g-6144.86g;(5) slope dynamic runoff and runoff of other things being equal, a different slope, slope gradient increases, that is, 25°> 20°> 15°> 10°> 5°;(6) Runoff sediment concentration in the other conditions the same, different slope, as slope increases, ie, 25°> 20°> 15°> 10°> 5°;(7) slope cumulative production of sand total with slope gradient, rainfall intensity of 60mm / h, the sediment yield total maintained at about 5300g-6100g, and the other conditions of rainfall intensity and sediment yield total with the degree of increaseincrease, ie, 25°> 20°> 15°> 10°> 5°;(8) Runoff coefficient of variation of the order of each rainfall intensity, runoff coefficient curve slope for 85mm / h> 100mm / h> 60mm / h under the conditions of the same rainfall intensity, runoff coefficient as the slope increases with increasing, ie25°> 20°> 15°> 10°> 5°;(9), the runoff depth increased with the increase of rainfall intensity by the slope factor has little effect. Rainfall intensity of 60mm / h, the runoff depth is 33.33mm-35.45mm, the rainfall intensity of 85mm / h, runoff depth is 44.57mm-52.90mm, when the rainfall intensity of 100mm / h, the runoff depth is 54.10mm-60.32mm ;(10) Simulated rainfall, the use of the nature of the RUSLE model measured limestone soil erodibility K values are an average of .0186 t ? h / (MJ mm), the erodibility Kwi average 0.0181kg/m2 ? mm. Relation to the calculation of the soil erodibility K values measured K value of 0.0194 t ? h / (MJ mm).