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土壤侵蚀是水土流失预测的主要内容,科学合理地预测开发建设项目的土壤侵蚀量非常重要。在无参照项目、无土壤侵蚀监测资料情况下,水土流失量的预测常采用土壤侵蚀模数法。文章应用土壤流失方程(USLE)预测土壤侵蚀量,探讨更科学的水电建设项目水土流失预测方法。 相似文献
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在介绍美国通用土壤流失方程各项因子概念及计算方法基础上,以福山流域不同地形组合区的降雨径流和泥沙等试验资料,对通用土壤流失方程进行了应用论证。 相似文献
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运用水土流失方程原理,在GIS技术支持下对江门市水土流失信息进行准确提取,并分析不同植被覆盖、地形坡度和降水条件下区域水土流失规律特征。结果表明:江门市水土流失以微度为主,占区域面积的72.23%,其他强度水土流失分布均不足10%;该市年均侵蚀模数为208.46 t·km~(-2)·a~(-1),流失量为200.65万t;随着植被覆盖度的增加侵蚀模数呈先增大后减小的趋势,特别是40%~50%植被覆盖的乔木林下,水土流失严峻;侵蚀模数与坡度呈正向相关,并且坡度在15°~25°的地带水土流失量最大;区域降水量与输沙量具有高度一致关系。 相似文献
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类比法预测开发建设项目水土流失几个问题的探讨 总被引:2,自引:0,他引:2
类比法是开发建设项目水土流失预测的一个重要方法,文章通过对类比工程选择中几个基本因素的总结和行分析,提出了类比工程选择中应注意的几个问题,并根据通用土壤流失方程式原理,建立了采用类比法预测开发建设项目水土流失的数学模型。 相似文献
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湟水流域是青海省工农业生产基地,也是青海省主要水土流失区。利用湟水流域主要测站的水文资料,对流域水沙特征及其来源进行了分析,对于研究流域水土流失规律和综合治理提供了一定的科学依据。 相似文献
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Estimation of Soil Erosion for a Himalayan Watershed Using GIS Technique 总被引:12,自引:0,他引:12
The fragile ecosystem of the Himalayas has been an increasing cause of concern to environmentalists and water resources planners. The steep slopes in the Himalayas along with depletedforest cover, as well as high seismicity have been major factors in soil erosion and sedimentation in river reaches. Prediction ofsoil erosion is a necessity if adequate provision is to be madein the design of conservation structures to offset the ill effects of sedimentation during their lifetime.In the present study, two different soil erosion models, i.e. theMorgan model and Universal Soil Loss Equation (USLE) model, have been used to estimate soil erosion from a Himalayan watershed.Parameters required for both models were generated using remotesensing and ancillary data in GIS mode. The soil erosion estimated by Morgan model is in the order of 2200 t km-2 yr-1 and is within the limits reported for this region.The soil erosion estimated by USLE gives a higher rate. Therefore, for the present study the Morgan model gives, for area located in hilly terrain, fairly good results. 相似文献
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昆明市松华坝水源区小流域土壤侵蚀分析 总被引:1,自引:0,他引:1
以1993-2009年松华坝水源区及昆明市的气象资料、2009年土地利用资料、第二次全国土壤普查资料、水源区牧羊河小流域的径流和泥沙观测资料为基础,用SWAT模型模拟分析了牧羊流域土壤侵蚀的空间差异。结果表明:牧羊河小流域输沙在年际上表现为与年降水量和输沙量峰谷变化具有较好的一致性,在年内表现出,输沙主要集中在6-9月;空间上牧羊河土壤侵蚀模数多年平均值介于21.4~4 586.5 t/(km2·a),且以中轻度为主,土壤侵蚀模数的空间变化与土地利用类型和地形坡度密切相关;土壤侵蚀模数与降水在年际变化上有较好的一致性。这一研究可为水源区土壤侵蚀空间分布的掌握和估算,以及制定有针对性的水土保持措施提供重要的理论依据。 相似文献
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三峡库区下岸溪小流域水土流失现状评估 总被引:2,自引:1,他引:2
以三峡库区下岸溪小流域为研究区,在GIS软件的支持下,利用2008年SPOT5遥感影像和1∶5万DEM数据,提取坡度因子、植被覆盖度因子和土地利用类型因子作为水土流失风险评估指标因子,结合土壤侵蚀分级标准,生成研究区水土流失风险分级图,利用改进的工程侵蚀模数计算模型,对小流域土壤侵蚀量进行了估算。结果表明:①本流域以水力侵蚀为主,占研究区总面积的88.81%,其中中度侵蚀面积占该流域总面积的38.49%;②开矿等引起的工程侵蚀对该小流域土壤侵蚀量贡献率很大,占该流域水土流失量的41.43%。因此,在开矿和矿区基础设施建设等工程施工时,应采取有效的水土保持措施。 相似文献
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铯-137同位素示踪法测算小流域土壤侵蚀量的研究 总被引:1,自引:0,他引:1
介绍了~(137)Cs方法测算土壤侵蚀量的基本原理。研制了适合复杂岩性侵蚀区使用的~(137)Cs侵蚀模型。并以鄂东花岗片麻岩侵蚀区的某荒坡小流域为例,计算了其坡面土壤侵蚀量和侵蚀模数,计算结果与径流场实测结果十分接近。此外,还对该流域坡面土壤侵蚀的分选性做了初步评价。 相似文献
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Soil Erosion Assessment in a Hilly Catchment of North Eastern India Using USLE, GIS and Remote Sensing 总被引:9,自引:1,他引:8
In the present study, soil erosion assessment of Dikrong river basin of Arunachal Pradesh (India) was carried out. The river
basin was divided into 200 × 200 m grid cells. The Arc Info 7.2 GIS software and RS (ERDAS IMAGINE 8.4 image processing software)
provided spatial input data and the USLE was used to predict the spatial distribution of the average annual soil loss on grid
basis. The average rainfall erositivity factor (R) for Dikrong river basin was found to be 1,894.6 MJ mm ha−1 h−1 year−1. The soil erodibility factor (K) with a magnitude of 0.055 t ha h ha−1 MJ−1 mm−1 is the highest, with 0.039 t ha h ha−1 MJ−1 mm−1 is the least for the watershed. The highest and lowest value of slope length factor (LS) is 53.5 and 5.39 respectively for the watershed. The highest and lowest values of crop management factor (C) were found out to be 0.004 and 1.0 respectively for the watershed. The highest and lowest value of conservation factor (P) were found to be 1 and 0.28 respectively for the watershed. The average annual soil loss of the Dikrong river basin is 51 t
ha−1 year−1. About 25.61% of the watershed area is found out to be under slight erosion class. Areas covered by moderate, high, very
high, severe and very severe erosion potential zones are 26.51%, 17.87%, 13.74%, 2.39% and 13.88% respectively. Therefore,
these areas need immediate attention from soil conservation point of view. 相似文献
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Integration of GIS with USLE in Assessment of Soil Erosion 总被引:8,自引:1,他引:8
A Geographic Information System (GIS) has been integrated with the USLE (Universal Soil Loss Equation) model in identification of rainfall-based erosion and the transport of nonpoint source pollution loads to the Gediz River, which discharges into the Aegean Sea along the western coast of Turkey. The purpose of the study is to identify the gross erosion, sediment loads, and organic N loads within a small region of the Gediz River basin. Similar studies are available in literature, ranging from those that use a simple model such as USLE to others of a more sophisticated nature. The study presented here reflects the difficulties in applying the methodology when the required data on soil properties, land use and vegetation are deficient in both quantity and quality, as the case is with most developing countries. 相似文献
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桥子沟流域“1987.4.19”暴雨洪水及土壤侵蚀调查分析 总被引:3,自引:0,他引:3
桥子沟流域属黄土丘陵沟壑区第三副区。1987年4月19日,该流域突降暴雨,造成了严重的水土流失。此次暴雨降雨集中、历时知、强度大,所形成的洪水历时短、峰值大。土壤侵蚀调查分析结果表明,本次暴雨造成该流域坡面总侵蚀量20190t,平均侵蚀模数为8738t/km^2,造成该流域沟道总侵蚀量7087t,侵蚀模数为50860t/km^2;坡面和沟道侵蚀量所占比例分别为74%和26%。 相似文献