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1.
贵州省猫跳河流域土壤侵蚀量计算及其背景空间分析   总被引:11,自引:2,他引:11  
以贵州省猫跳河流域为研究区,在GIS 技术支撑下,应用修正的通用土壤流失方程计算研究区的土壤侵蚀量,分析土壤侵蚀的空间分布格局,对土壤侵蚀与其环境背景因子包括海拔高程、坡度、坡向和土地利用类型等进行叠加和空间统计分析,揭示土壤侵蚀与其环境背景等因子的空间关系,为土壤侵蚀的有效防治和治理提供科学依据。结果表明:研究区平均土壤侵蚀模数为28.6 t/(hm2·a),1200~1400 m的海拔高程带、6°~25°坡度带和南坡是发生土壤侵蚀的主要区域,也是水土流失防治及治理的重点区域。在各种土地利用类型中,旱地发生土壤侵蚀面积和侵蚀量最大,其次是灌草地,水田最小。在县域中,清镇市土壤侵蚀面积和土壤侵蚀量最大,其次是平坝县和修文县,息烽县土壤侵蚀面积和土壤侵蚀量最小。  相似文献   

2.
This study evaluates surface runoff generation and soil erosion rates for a small watershed (the Keleta Watershed) in the Awash River basin of Ethiopia by using the Soil and Water Assessment Tool (SWAT) model. Calibration and validation of the model was performed on monthly basis, and it could simulate surface runoff and soil erosion to a good level of accuracy. The simulated surface runoff closely matched with observed data (derived by hydrograph separation). Surface runoff generation was generally high in parts of the watershed characterized by heavy clay soils with low infiltration capacity, agricultural land use and slope gradients of over 25 per cent. The estimated soil loss rates were also realistic compared to what can be observed in the field and results from previous studies. The long‐term average soil loss was estimated at 4·3 t ha−1 y−1; most of the area of the watershed (∼80 per cent) was predicted to suffer from a low or moderate erosion risk (<8 t ha−1 y−1), and only in ∼1·2 per cent of the watershed was soil erosion estimated to exceed 12 t ha−1 y−1. Expectedly, estimated soil loss was significantly correlated with measured rainfall and simulated surface runoff. Based on the estimated soil loss rates, the watershed was divided into four priority categories for conservation intervention. The study demonstrates that the SWAT model provides a useful tool for soil erosion assessment from watersheds and facilitates planning for a sustainable land management in Ethiopia. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

3.
Soil erosion by water is the most pressing environmental problem in Ethiopia, particularly in the Highlands where the topography is highly rugged, population pressure is high, steeplands are cultivated and rainfall is erosive. Soil conservation is critically required in these areas. The objective of this study was to assess soil erosion hazard in a typical highland watershed (the Chemoga watershed) and demonstrate that a simple erosion assessment model, the universal soil loss equation (USLE), integrated with satellite remote sensing and geographical information systems can provide useful tools for conservation decision‐making. Monthly precipitation, soil map, a 30‐m digital elevation model derived from topographic map, land‐cover map produced from supervised classification of a Land Sat image, and land use types and slope steepness were used to determine the USLE factor values. The results show that a larger part of the watershed (>58 per cent of total) suffers from a severe or very severe erosion risk (>80 t ha−1 y−1), mainly in the midstream and upstream parts where steeplands are cultivated or overgrazed. In about 25 per cent of the watershed, soil erosion was estimated to exceed 125 t ha−1 y−1. Based on the predicted soil erosion rates, the watershed was divided into six priority categories for conservation intervention and 18 micro‐watersheds were identified that may be used as planning units. Finally, the method used has yielded a fairly reliable estimation of soil loss rates and delineation of erosion‐prone areas. Hence, a similar method can be used in other watersheds to prepare conservation master plans and enable efficient use of limited resources. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

4.
丹江鹦鹉沟小流域土壤侵蚀和养分损失定量分析   总被引:5,自引:1,他引:4  
小流域土壤侵蚀量和养分损失量的定量研究可为南水北调水源区的生态保护、水土保持和生态补偿提供重要的依据.该文在地理信息技术(geographic information system,GIS)的支持下,应用修正通用土壤流失方程(revised universal soil loss equation,RUSLE)估算了丹江鹦鹉沟流域的土壤侵蚀量和养分损失量,并进行了土壤侵蚀强度分级.结果表明,流域的年均土壤侵蚀模数为3140 t/km2,侵蚀强度为中度.其中强度侵蚀以上的土地面积占流域总面积的24.1%,侵蚀量为4573.0 t,却占年侵蚀总量的84.8%,其主要是坡度较大的坡耕地,是流域需要重点治理的区域.不同土地利用类型的土壤侵蚀量差异较大,林地、草地和农地的年均土壤侵蚀模数分别为509.7、1511.8和4606.5 t/km2.林草地年侵蚀量较小,农地土壤侵蚀量占流域总侵蚀量的95.3%.坡度每增加5°,不同土地利用的土壤侵蚀模数增加量比坡长每增加5 m的增加量要大1~2倍.研究区表土流失造成的全氮、全磷和有机质损失量分别为3.81、3.52和101.45 t,其中农地的养分损失量最为严重.流域泥沙中全氮、全磷和有机质的年均流失模数分别为1.01、0.75和38.43 t/(km2×a).该研究可为水源区水土流失和非点源污染治理以及清洁小流域建设提供科学依据.  相似文献   

5.
中国水土流失防治任务仍然繁重,有计划分批次实施水土流失治理是现阶段条件下的必然选择,优先治理小流域识别是其首要解决的一项基础工作,然而目前相关成果较为缺乏,难以支撑小流域水土流失治理智能决策和精准施策。在当前大力推进智慧水土保持背景下,积极探索优先治理小流域识别方法非常迫切,对于科学、合理、高效促进水土流失治理工作具有重要意义。该研究立足于小流域自然禀赋条件,以中国水土流失重点区域——三峡库区秭归县为例,坚持科学性和可操作性相结合原则,以水土流失“减量和降级”双重目标和治理效益最大化需求为导向,综合水土流失面积和土壤侵蚀强度两个维度,提出小流域水土流失治理优先度定义及定量评价方法,为识别优先治理小流域提供科学依据和技术支撑。结果显示,秭归县2021年现状水土保持率为69.12%,远期(2050年)水土保持率为81.74%,总体提升12.62个百分点。秭归县2021年全域土壤侵蚀模数现状为758.50 t/(km2·a),最小可能土壤侵蚀模数为408.71 t/(km2·a),总体下降比例达46%。秭归县大部分区域均具有较大的水土保持率提升潜力和土壤侵蚀控制度,可完全治理和可降级的水土流失地块分布较为广泛,尤其在县域中西部的小流域存在较大的水土流失面积消减和土壤侵蚀强度降级空间。秭归县各小流域水土流失治理优先度的空间分布总体呈现中部高,东部和南部相对较低的分布格局,全县治理优先度大于0.6的小流域占总全县小流域的11.76%。通过典型县应用,该研究提出的小流域治理优先度涵盖了水土流失面积和土壤侵蚀强度两个维度,能更为全面满足小流域水土流失“减量和降级”双重目标和和治理效益最大化需求,直观反映了水土流失面积消减空间和土壤侵蚀强度降级空间的目标和相对大小,对支撑小流域治理决策更加准确、科学,治理优先度评价方法不仅可行,且易操作。  相似文献   

6.
The objective of this study was to evaluate the impact of rapidly changing land use on erosion and sedimentation in a mixed land use watershed in the Ozark Highlands of the USA. The research combines a geographic information system‐based soil erosion modeling approach with land use change detection to quantify the influence of changing land use on erosion risk. Five land use/land cover maps were generated or acquired for a 20‐year period (1986 through 2006) at approximately 5‐year intervals to assess land use change and to predict a projected (2030) land use scenario for the West Fork White River watershed in Northwest Arkansas. The Unit Stream Power based Erosion/Deposition model was applied to the observed and predicted land use to assess the impact on erosion. Total erosion from urban areas was predicted to increase by a factor of six between 1986 and 2030 based on the projected 2030 land use. Results support previous reports of increased urbanization leading to increased soil erosion risk. This study highlights the interaction of changes in land use with soil erosion potential. Soil erosion risk on a landscape can be quantified by incorporating commonly available biophysical data with geographic information system and remote sensing, which could serve as a land/watershed management tool for the rapid assessment of the effects of environmental change on erosion risk. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

7.
Land use and land cover change (LULCC) directly affect the temporal and spatial change of soil erosion. As a typical governance watershed in the hilly and gully area of the Loess Plateau, the Jiuyuangou watershed has experienced significant LULCC in the past 10 years due to conversion of farmland to forests, economic construction, and cropland abandonment. However, the evolution process of soil erosion change and LULCC in the watershed is unclear, as is the relationship between the two. This study used satellite images to extract information on LULCC in the watershed and the Chinese soil loss equation (CSLE) model to evaluate the temporal and spatial evolution of soil erosion in the watershed from 2010 to 2020. The main results showed that (1) the continuous vegetation restoration project in the watershed reduced soil erosion from 2010 to 2015; however, the increased frequency of extreme rainfall events after 2015 reduced its impact. The annual average soil erosion modulus decreased from 10.85 t ha−1 year−1 in 2010 to 8.03 t ha−1 year−1 in 2015 but then increased to 10.57 t ha−1 year−1 in 2020; (2) the main land use and land cover (LULC) type in the Jiuyuangou watershed is grassland, accounting for 62% of the total area, followed by forestland, cropland, buildings, and water. Cropland has the largest multi-year average soil erosion modulus, followed by grassland and buildings, with forestland having the smallest; (3) significant spatial correlations occurred between soil erosion change and LULCC for common ‘no change’ and common ‘gain’ in the settlements, roads, and areas near the human influences with good soil and water conservation, but not other regions due to the influence of climatic factors (heavy rain events). Thus, we should repair terraces, control dams in the watershed, and actively conserve water and soil. This study provides a scientific reference for planning and managing water and soil conservation and ecological environment construction in the watershed.  相似文献   

8.
为探究安徽省青弋江流域土壤侵蚀的演变规律和驱动因素,采用InVEST模型对该流域2000—2018年的土壤侵蚀特征开展了研究,量化了不同土地利用类型、海拔、坡度下土壤侵蚀状况,并借助地理探测器对流域土壤侵蚀影响因素进行分析。结果表明:(1)2000年、2010年、2018年该流域平均土壤侵蚀模数分别为15.29,14.14,10.74 t/(hm2·a),侵蚀总量分别为1.08×107,1.00×107,0.76×107 t,呈现逐渐减小特征;(2)流域内土壤侵蚀空间差异显著,呈现“北低南高”的分布格局;(3)不同土地利用类型土壤侵蚀模数大小表现为裸地>草地>林地>耕地>建设用地>水体,全流域林地侵蚀量最大,占总侵蚀量的73.71%;(4)地形因子对流域内土壤侵蚀存在显著影响,坡度是青弋江流域土壤侵蚀主导因子,因子间交互作用对土壤侵蚀的解释力均大于单因子,其中坡度与年降水量和土地利用的协同作用解释力最强,分别达22.93%和22.29%;(5)坡地坡度降缓及增加草地和林...  相似文献   

9.
北方土石山区水土流失现状与综合治理对策   总被引:9,自引:0,他引:9       下载免费PDF全文
北方土石山区现有轻度以上水土流失面积13.49万km^2,其中水蚀面积约占95%,水蚀区虽以轻度侵蚀为主,但水土流失仍然是该区主要的生态环境问题,不仅制约山区经济的发展,而且严重影响下游经济发达地区的水资源安全和生态安全,加强区域水土保持已成为区域发展的迫切要求。北方土石山区的水土保持,在新的时代背景下,应更加关注坡耕地改造、“坡林地”水土保持、“节水型”措施和生态“清洁型”小流域建设。依据自然地带性规律、区域经济发展和社会需求,北方土石山区可分为8个水土流失综合治理区,各区应当结合实际情况采取有针对性的综合治理对策。  相似文献   

10.
基于CSLE模型的陕北纸坊沟流域土壤侵蚀评价   总被引:4,自引:1,他引:3  
[目的]对陕北纸坊沟流域土壤侵蚀状况进行评价,为该流域不合理土地利用方式的调整和优化以及水土流失治理措施的合理布设提供科学依据。[方法]以陕西省安塞县纸坊沟流域为研究区,基于ArcGIS技术,利用2005—2016年纸坊沟流域水文站月降雨量数据、DEM数据、土壤类型数据和土地利用数据,率定中国土壤流失方程(CSLE)的相关参数,计算研究区的土壤侵蚀强度,对土地利用变化与坡度和土壤侵蚀强度之间的关系进行分析。[结果](1)研究区内不同坡度带上的土壤侵蚀强度差异较大,15°~25°左右的坡耕地是土壤侵蚀的敏感部位。(2)纸坊沟流域内土地以林地、耕地、草地为主,耕地面积不断减少,林地和草地面积不断增加。该区域实施退耕还林后,土壤侵蚀的面积与强度整体呈现改善趋势;土地利用变化与土壤侵蚀强度具有密切联系,表现为耕地的土壤侵蚀强度较强,林地和草地侵蚀强度相对较弱,说明增加林地和草地面积,减少耕地面积,能够显著减弱土壤侵蚀。[结论]研究区内土壤侵蚀空间分布受土地利用方式和坡度制约,该区今后水土流失治理的重点区域是15°~25°左右的坡耕地。  相似文献   

11.
流域土壤侵蚀动态模拟,需要采用合适的方法对坡面—沟道耦合问题及初始和边界条件进行正确的处理。将流域划分为坡面侵蚀与沟道侵蚀,采用时间空间耦合处理方法,实现了小流域坡—沟侵蚀过程中水流与泥沙输送的面—线耦合及沟道间的线—线连接。给出了模拟流域土壤侵蚀过程的控制微分方程、初始条件、边界条件及坡面向沟道汇水输沙的动态模拟处理方法。得到了较为符合实际的流域土壤侵蚀动态模拟模型。模拟结果与室内实验测量结果的比较表明,模拟精度达到80%以上,说明了动态模拟方法的可行性。  相似文献   

12.
紫色土小流域土壤流失对不同土地利用类型的响应   总被引:6,自引:0,他引:6       下载免费PDF全文
 小流域土壤流失特征不仅反映了流域的土地利用和管理状况,而且对其下游水体环境和水利设施安全具有深刻的影响。1999—2000年间以紫色土区3个具有不同集水面积、物理特征和土地利用类型的典型小流域为研究对象,探讨不同雨型下土壤流失对不同土地利用类型的响应特征。中大型降雨和间歇型降雨侵蚀下,以林地为主要土地利用类型的流域输沙模数最小,平均为866kg·hm-2,谷地农田利用类型最高,平均为5 550kg·hm-2。次降雨侵蚀力和次降雨峰值径流流量,分别是紫色土区非林地和林地利用为主小流域输沙模数变异的主要影响因子。  相似文献   

13.
北京山区土壤流失方程探讨   总被引:20,自引:1,他引:20       下载免费PDF全文
 水土流失是生态环境恶化的重要原因之一。土壤流失方程是定量评价水土资源发展动态、指导综合治理规划和评价水土流失治理效果的重要技术工具。利用北京近1000个坡面径流试验小区的年降雨、径流和泥沙资料以及人工降雨试验资料,并考虑北京石质山区存在大量砾石覆盖地表的特点,将砾石覆盖因子作为一个独立的因子考虑在土壤流失方程中。得到北京山区坡面土壤侵蚀方程,并确定了方程中各个因子的计算方法或数值。该方程的建立,可为北京山区土壤侵蚀动态监测和水土保持规划提供依据。  相似文献   

14.
Ecuador has the highest deforestation rate in South America, causing large‐scale soil erosion. Inter‐Andean watersheds are especially affected by a rapid increase of the population leading to the conversion of large areas of montane forest into pasture and cropland. In this study, we estimate soil erosion risk in a small mixed land‐use watershed in the southern Andes of Ecuador. Soil loss was estimated at a spatial resolution of 30 m, using the Revised Universal Soil Loss Equation (RUSLE) where the RUSLE factors were estimated on the basis of limited public available data. Land‐cover maps for 1976, 2008 and 2040 were created assuming increasing deforestation rates over the ensuing decades. Greater erosion rates are estimated for succession areas with agricultural cropland and pasture with maximum values of 936 Mg ha−1 y−1, where slopes and precipitation amounts are the greatest. Under natural forest vegetation, the estimated soil erosion rates are negligible (1·5 to 40 Mg ha−1 y−1) even at steep slopes and higher elevations where rainfall amounts and intensities are generally higher. When the entire watershed has undergone substantial deforestation in 2040, erosion values may reach 2,021 Mg ha−1 y−1. Vegetation cover is the most important factor for potential soil erosion. Secondary factors are related to rainfall (R‐factor) and topography (LS factors). Although the spatial predictions of potential soil erosion have only limited meaning for erosion risk, this method provides an important screening tool for land management and assessment of land‐cover change. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

15.
《CATENA》1999,38(2):109-129
This research integrates the Revised Universal Soil Loss Equation (RUSLE) with a Geographic Information System (GIS) to model erosion potential for soil conservation planning within the Sierra de Manantlán Biosphere Reserve (SMBR), Mexico. Mountainous topography and a tropical uni-modal precipitation regime characterize this region. These unique climatic and topographic characteristics required a modification of the standard RUSLE factors and their derivation. The resulting RUSLE–GIS model provides a robust soil conservation planning tool readily transferable and accessible to other land managers in similar environments. Future pressure to expand agriculture and grazing operations within the SMBR will unquestionably accentuate the already high rate of soil erosion and resultant sediment loading of watercourses occurring in this region. Until recently there did not exist a reliable or financially viable means to model and map soil erosion within large remote areas. An increase in the reliability and resolution of remote sensing techniques, modifications and advancements in watershed scale soil erosion modelling techniques, and advances in GIS, represent significantly improved tools that can be applied to both monitoring and modelling the effects of land use on soil erosion potential. Data used in this study to generate the RUSLE variables include a Landsat Thematic Mapper image (land cover), digitized topographic and soil maps, and tabular precipitation data. Soil erosion potential was modelled within Zenzontla, a sub-catchment of the Rı́o Ayuquı́la, located in the SMBR, and the results are presented as geo-referenced maps for each of the wet and dry precipitation seasons. These maps confirm that high and extreme areas of soil loss occur within the Zenzontla sub-catchment, and that erosion potential differs significantly between wet and dry seasons.  相似文献   

16.
Soil quality assessment has been recognized as an important step toward understanding the long-term effects of conservation practices within agricultural watersheds. Our objective was to assess soil quality within the South Fork watershed of the Iowa River using various indicators and assessment approaches. Soil samples were collected during 2003 and 2004 from 29 areas of 32 ha (80 acres) each along two transects traversing the watershed. Soil pH, Mehlich III extractable P, K, Ca and Mg, electrical conductivity (EC), total organic carbon (TOC), and total N (TN) were measured. The Soil Management Assessment Framework (SMAF) was used to compute a soil quality index (SQI), while soil loss, the soil tillage intensity rating (STIR), N-leaching potential, and soil conditioning index (SCI) were determined for each sampling area using the 2003 version of the Revised Soil Loss Equation (RUSLE2). Overall, there were no soil fertility limitations within the watershed based on an average pH of 6.96 and extractable P and K levels of 36 and 162 mg kg−1, respectively. Soil loss, STIR, N-leaching, and SCI averaged 1.13 Mg ha−1, 68, 3, and 0.4, respectively. The SMAF analysis indicated soils within the watershed were functioning at 87% of their full potential. The lowest indicator score was associated with TOC (0.60) because the average value was only 28.4 g kg−1. The SCI and SQI indices were positively correlated although since it used measured data, the SMAF appears to provide more information about the effects of management practices within the watershed. Soils in upper landscape positions had lower TOC and C:N ratios indicating an increased risks for both erosion and for nitrate leaching. Management of soils on hilltops may be the most effective way to minimize N and P losses within the watershed.  相似文献   

17.
[目的]内蒙古十大孔兑地区属黄河中上游多沙粗沙区和生态脆弱区,对该区典型流域西柳沟的土壤侵蚀进行实地调查,分析流域土壤侵蚀特征及成因,为该区水土流失防治提供科学依据。[方法]于2022年9月19—26日和2023年6月21—26日沿X640解柴线(解家营—柴沟堡)和G109京拉线(北京—拉萨)2条公路分别布设15个调查点和14个集水区,对调查点及集水区植被、土壤、土壤侵蚀特征和水土保持措施等进行调查。[结果]流域内草地片蚀较为严重,耕地侵蚀不严重,沟谷内裸地风蚀较为严重。上游黄土高原丘陵区沟蚀严重,且溯源侵蚀、下切侵蚀及沟岸扩张未停止,伴随较为严重的重力侵蚀。中游风沙区以风水复合侵蚀为主,大幅增加了流域的产沙总量。流域内道路建设及边坡开挖等人为扰动进一步加剧了侵蚀风险。径流泥沙含量测定结果验证了流域泥沙的主要来源为上游地区。流域内水土保持措施以植被措施及工程措施为主,虽已起到一定水土保持作用,但由于形式单一而未能发挥理想效果。[结论]西柳沟短历时高强度的降雨特点叠加下层砒砂岩土壤条件共同加剧了该区土壤侵蚀,经济发展压力下的人类活动扰动加剧了生态风险,当地政府亟需持续增加水土保持投入,提...  相似文献   

18.
南方红壤侵蚀区典型流域土壤侵蚀危险性评价   总被引:3,自引:0,他引:3  
陈志强  陈志彪  陈丽慧 《土壤学报》2011,48(5):1080-1082
土壤侵蚀危险性可对土壤侵蚀发生的可能性、程度和侵蚀发展进行估测评价[1],对保护土壤资源、农业开发及经济建设具有预防预警的重大意义[2]。对此不少学者已开展了相关研究,取得了一定成果[3]。目前,土壤侵蚀危险性的评价方法主要有两种:土壤抗蚀年限法和土壤侵蚀因子权重评分  相似文献   

19.
Soil and water conservation practices have been extensively used in effective watershed management. The impact of each conservation practice is site specific and dependent on the implementation site in the watershed. In order to select cost effective placement of conservation practices with high impact, a large number of spatial combinations is needed to be compared. In this study, an optimization model framework is presented to find cost effective solutions for sediment yield and runoff control in the Fariman dam watershed in the Northeast of Iran. This was accomplished by integrating soil and water assessment tool (SWAT) for simulation of watershed hydrology and multi objective genetic algorithm (NSGA-II) for spatial optimization of soil and water conservation practices. The optimized solutions provided a trade-off between the two objective functions. The final Pareto-optimal shows that the impact of soil and water conservation practices on sediment yield is more than stream flow. The trade-offs between the objective functions show that the implementation of the median cost can lead to a significant decrease of 22.1% in the amount of sediment yield, and 10% in stream flow. Also, percent change achieved through median cost is very close to percent reduction with the highest cost. Results of low cost solution show that the vegetative practices are a suitable economic scenario for soil and water conservation. The introduced framework can be adapted as a suitable tool for selecting cost effective conservation practices in different regions.  相似文献   

20.
《CATENA》2004,55(1):33-48
The Three Gorge Project (TGP) of China necessitates the resettlement of over 1 million population (mostly farmers) to more rugged and isolated areas than their original settlements. Soil erosion is a serious environmental and production problem in this area. To decrease the risk on environmental impacts, there is an increasing demand for sound, and readily applicable techniques for soil conservation planning in the Three Gorge Areas (TGA). The objectives of the study were to develop and validate a soil erosion-predicting model based on the revised Universal Soil Loss Equation (RUSLE) in a geographic information systems (GIS) environment. The use of GIS to develop conservation-oriented watershed management strategies in the Wangjiaqiao watershed is presented. Data used for the RUSLE were either determined or taken from published literature pertaining to the Wangjiaqiao watershed. In combination with IDRISI, GIS software (Eastman, R.J., 1997. IDRISI for Windows: User's guide (Version 2.0). Clark University, Graduate School of Geography, Worcester, MA, Chapters 4–17) was used to evaluate different agricultural management strategies in terms of predicted soil loss in the watershed. This model allowed for easy assessment of soil erosion hazards under different crop and land management options over the entire watershed. The study revealed that the annual average soil loss rate from relatively flat agricultural land was approximately 26 t/ha, whereas 52 t/ha was found on the cultivated sloping lands, which constitutes a large proportion of soil loss in the watershed. In the watershed, approximately 38 ha of agricultural land had slopes >47% (25°) and should be reforested or returned to pasture. Contour tillage (CT) and contour farming with a seasonal no-till ridge (CTN) were most effective in reducing soil loss rates. If CT and CTN were implemented, approximately 31% and 70%, respectively, of the areas with soil loss >TEP would be reduced to <TEP. TEP is soil loss tolerance for economic planning and was set at ≤10 t/ha year. In addition to soil loss reduction, the CTN has the potential to increase crop yield. Soil erosion hazards may be alleviated in over 91% of the agricultural lands if combined conservation measures including terraces, CTN, CT, and crop rotations were implemented in the watershed. The results of the study indicate that the RUSLE-GIS model is a useful tool for resource management and soil conservation planning. This technology is readily transferable and accessible to other land managers and agronomists in the TGA.  相似文献   

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