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 This artical is focused on the relationship between the effects of water and soil conservation and vegetation. The results are as follows:Ⅰ. The recovery increments of vegetationIn mountainous area:On the northern slope is 9.2% / per year, on the southern slope is 9.0% / per year.In hill area:On the northern slope is 8.3% / per year, on the southern slope is 7.6% / per year.Ⅱ. The increasing effects of vegetation on runoff are as follows:1. Shortening the process of runoff, 2. Lowering the peak of flow, 3. Increasing... This artical is focused on the relationship between the effects of water and soil conservation and vegetation. The results are as follows:Ⅰ. The recovery increments of vegetationIn mountainous area:On the northern slope is 9.2% / per year, on the southern slope is 9.0% / per year.In hill area:On the northern slope is 8.3% / per year, on the southern slope is 7.6% / per year.Ⅱ. The increasing effects of vegetation on runoff are as follows:1. Shortening the process of runoff, 2. Lowering the peak of flow, 3. Increasing the permeability of the soil, 4. Lessening the amount of runoff.Thus when vegetation increased 1% the coefficient of runoff would be decreased 1.04— 1.2% accordingly. If vegetation increased to 90%, the runoff would be fundamentaly controlled.Ⅲ. The relationship between vegetation and the soil surface erosion are as follows:The relationship between vegetation and soil surface erosion is in inverse proportion.When vegetation is less than 60%, the curve of the soil surface erosion prets a elevation manner by a 45° angle. When vegetation increases to 90%, the soil surface erosion is basicaly controlled.  本文通过多年调查观测的资料,论证了植物措施与保持水土的关系,植被覆盖度与实施植物水土保持措施的年限成正比的关系。植被结构的改良,植被覆盖度的增长,可以缩短地表径流过程,降低径流洪峰量,增加土壤入渗量,减少地表径流量。植被覆盖度与土壤面蚀成反比的关系。植被覆盖度小于60％时,土壤侵蚀量急剧上升,覆盖度增长到60％以上时,土壤侵蚀量明显减少,覆盖度增长到60％以上时,土壤侵蚀基本停止。  In this paper it is verified through experiment that the formulacan be used to calculate the. evaporation from land surface in mountainous area as well as inopen country. Here E0 is the evaporative power; r is the precipitation; m is a pararneterdepending on the nature of underlying surface,its expression is deduced theoretically as follows:where Y is the coefficient of runoff, r the precipitation intensity(mmd 1 ),a,c and n are constants. In the mountainous areas of Yunnan Province, a = 0． 829,c =... In this paper it is verified through experiment that the formulacan be used to calculate the. evaporation from land surface in mountainous area as well as inopen country. Here E0 is the evaporative power; r is the precipitation; m is a pararneterdepending on the nature of underlying surface,its expression is deduced theoretically as follows:where Y is the coefficient of runoff, r the precipitation intensity(mmd 1 ),a,c and n are constants. In the mountainous areas of Yunnan Province, a = 0． 829,c = 0. 277, n = 0. 693, themean relative error in calculating the annual evaporations from land surface by formula (1 )with m determlned by expression (2) is 4． 2％.  本文研讨了山地下垫面蒸发的计算，提出了根据迳流系数和降水强度确定计算蒸发公式中与地形、植被、土壤等下垫面特性及降水性质有关的参数的方法，经实际检验，结果令人满意。  Using method of statistical mechanics and maximum entrophy principle, we obtain that distributions of precipitation, mean depth and coefficient of runoff in a water shed can be described by a negative exponential function. In ahighmountainous basin, the maximum distributive area of precipitation, depth and coefficient of runoff is glacierized area. In this case, a calculation method of average mass balance for glaciers in a water shed has been suggested in this paper. We use the model to simulate... Using method of statistical mechanics and maximum entrophy principle, we obtain that distributions of precipitation, mean depth and coefficient of runoff in a water shed can be described by a negative exponential function. In ahighmountainous basin, the maximum distributive area of precipitation, depth and coefficient of runoff is glacierized area. In this case, a calculation method of average mass balance for glaciers in a water shed has been suggested in this paper. We use the model to simulate the mass balance of Glacier No. 1 at the Headwaters of the Urumqi River. The result is reasonable and well precise. For recovery of mass balance, the method is employed to the Kangxiwa River Basin of Muztagh AtaKongur Ata, East Pamir, and 123.5 mm/a of mean mass balance during 1960～1990 is worked out. Finally, the longterm trend of mass balance, together with hydrological response to mass balance and precipitation changing in Chinese Pamir, are discussed.  应用统计力学方法和最大熵原理，论证了高山流域内降水、径流和径流系数与其所占面积之间呈负指数关系，流域内的冰川分布区是各参数的最大分布区，从而给出了高山流域冰川平均物质平衡的计算公式。在乌鲁木齐河源１号冰川流域对公式进行了验证，结果说明此方法是可靠的，且精度较高。运用此公式对东帕米尔康西瓦河流域的冰川物质平衡进行恢复，１９６０～１９９０年平均值为－１２３．５ｍｍ／ａ。   << 更多相关文摘 
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