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1.
基于SWAT模型的中尺度流域产流产沙模拟研究   总被引:42,自引:5,他引:42  
以黄河下游小花间(小浪底-花园口)区域洛河卢氏水文站以上流域为研究区,在GIS技术支持下,应用分布式模型SWAT(Soil and Water Assessment Tool)进行了流域产流产沙模拟。采用卢氏水文站1992~1997连续6年的实测月均径流和泥沙数据对模型进行了校准:在模型校准过程采用自动数字滤波技术将径流总量划分为直接径流和基流,并分别对直接径流和基流进行了校准,以达到径流总量的拟合,在此基础上对流域泥沙负荷进行了校准;采用1998~1999连续2年的实测月均径流和泥沙数据对模型的适用性进  相似文献   

2.
Spatial accuracy of hydrologic modeling inputs influences the output from hydrologic models. A pertinent question is to know the optimal level of soil sampling or how many soil samples are needed for model input, in order to improve model predictions. In this study, measured soil properties were clustered into five different configurations as inputs to the Soil and Water Assessment Tool (SWAT) simulation of the Castor River watershed (11-km2 area) in southern Quebec, Canada. SWAT is a process-based model that predicts the impacts of climate and land use management on water yield, sediment, and nutrient fluxes. SWAT requires geographical information system inputs such as the digital elevation model as well as soil and land use maps. Mean values of soil properties are used in soil polygons (soil series); thus, the spatial variability of these properties is neglected. The primary objective of this study was to quantify the impacts of spatial variability of soil properties on the prediction of runoff, sediment, and total phosphorus using SWAT. The spatial clustering of the measured soil properties was undertaken using the regionalized with dynamically constrained agglomerative clustering and partitioning method. Measured soil data were clustered into 5, 10, 15, 20, and 24 heterogeneous regions. Soil data from the Castor watershed which have been used in previous studies was also set up and termed “Reference”. Overall, there was no significant difference in runoff simulation across the five configurations including the reference. This may be attributable to SWAT's use of the soil conservation service curve number method in flow simulation. Therefore having high spatial resolution inputs for soil data may not necessarily improve predictions when they are used in hydrologic modeling.  相似文献   

3.
以甘肃天水罗玉沟流域为研究区,应用分布式水文模型(SWAT)对该流域的径流、泥沙和水质状况进行模拟研究,并重点探讨了降雨和森林植被变化对水文生态响应的影响。结果表明:降雨因子对径流的影响略大于对泥沙的影响;森林植被具有明显的减水减沙生态水文功能,尤其对泥沙的影响更大于对径流的影响。  相似文献   

4.
土地利用变化对产流和产沙的影响分析   总被引:55,自引:4,他引:55  
LUCC(土地利用覆盖变化)对径流的影响研究主要集中在对年径流量的影响,选用基于ArcviewGIS的SWAT模型,利用情景模拟来分析土地利用变化对产流量和产沙量的影响,并重点探讨森林对产流的影响。以黄河下游支流洛河上游卢氏水文站以上流域为研究区域,选取了1992~2000年24个雨量站的雨量资料和同期的气象资料,采用土壤类型图(1∶4000000)以及设定的不同土地利用情景,作为模型的输入,进行土地利用变化的产流量和产沙量的情景模拟。模拟表明:森林的存在增加了径流量,减少了产沙量;草地也能减少产沙量;农业用地的增加将会增加产沙量;平水年土地利用变化对产流量影响最小,降雨量的增大能弱化下垫面对产流量的影响。  相似文献   

5.
以石匣小流域水土保持科技示范园10个不同水土保持措施配置模式的径流小区为研究对象,分析当地2004-2019年降雨格局变化,并以发生在2010-2018年的19次代表性强降雨作为样本降雨事件,探究不同配置模式对土壤侵蚀与面源污染特征的影响.结果 表明:(1)2004-2019年降雨量变化范围在331.4~598.9mm...  相似文献   

6.
探讨降雨量与水土保持措施对流域水沙关系的影响,对流域水土流失预报和水土保持效益评价具有十分重要的科学意义,但在紫色土区这方面的研究还相当薄弱。以鹤鸣观小流域Ⅱ号支沟实测降雨径流泥沙数据为基础,分析了水土保持措施对流域径流、泥沙及水沙关系的影响。结果表明:流域治理后期,降雨产流量变化率、降雨产沙量变化率均减小,随着降雨的增多,水土保持措施对径流、产沙的影响效应增强;暴雨强度愈小,降雨量愈少,水土保持径流拦蓄作用愈显著;但降雨量愈大,泥沙拦蓄作用愈显著;流域减水量一般在30%~70%,而减沙量都高于90%,减沙量明显高于减水量;由于水土保持综合治理的作用,1989年后的多年平均径流量较1989年前减少33.11%,多年平均产沙量减少90.50%。  相似文献   

7.
近50a来官厅水库上游流域泥沙输移平衡研究   总被引:2,自引:0,他引:2  
近50 a来官厅水库上游流域侵蚀产沙总量为4.57×109t,其中水土保持措施拦沙量7.71×108t,占总产沙量的16.89%;水利工程拦沙量7.65×108t,占总产沙量的16.76%;引洪淤灌减沙量9.65×108t,占总产沙量的21.14%;河道淤积沙量8.16x 108t.占总产沙量的17.88%;官厅水库淤积量7.50× 108t,占总产沙量的18.02%;官厅水库下泄4.25×108t,占总产沙量的9.31%.20世纪的后20 a,流域内的水土保持措施拦沙量大幅度提升,和1950-1980年间相比,水土保持措施拦沙率提高了26.27%.  相似文献   

8.
山西省生态环境用水初探   总被引:6,自引:1,他引:6       下载免费PDF全文
 生态环境用水研究是改善生态环境亟待解决的重大问题。从生态环境用水的内涵着手,结合山西省生态环境的实际情况,将山西省生态环境用水划分为森林植被、水土保持、河流、城市生态环境用水4个方面。森林植被生态环境用水用林地实际蒸散量表示,全省林地耗水大致为346~477mm;水土保持生态环境用水采用治理前后小流域对比分析方法,经水土保持综合治理后,减少流域径流深约为17.62mm(黄河流域)、27.34mm(海河流域);通过对山西省各大河流多年平均最小月径流量和最大月含沙量、输沙量统计分析,计算河流生态环境用水量;城市生态环境用水从城市湖泊环境用水、城市绿化用水、地下水超采恢复用水、城区道路洒水等方面进行分析。  相似文献   

9.
Assessing long-term hydrological impacts of land use/land cover (LULC) change is of critical importance for land use planning and water resource management. The Little River Watershed, Tennessee, is an important watershed supporting drinking water and recreational activities within and around the Great Smoky Mountains National Park in the Unites States. However, the potential hydrological impacts of LULC change, especially urbanization in recent decades, are not quantified. This paper assessed the long-term impacts of LULC change on streamflow and non-point source pollution using the Soil and Water Assessment Tool (SWAT) and a detailed LULC record from 1984 to 2010. The SWAT was first calibrated and validated using observed streamflowin 2010 and then simulated using different LULC patterns in 1984-2010 to quantify the long-term hydrological impacts caused by the LULC change. Simulated results indicated a minor 3% increase in streamflow for the whole watershed from 1984 to 2010, but with a distinct spatial pattern. The increase in streamflow is closely related to urban development. Almost no streamflow increase occurred in the upper watershed within the national park, whereas > 10% increase occurred in the lower watershed, especially in areas close to cities. Model simulation also suggested 34.6% reduction in sediment and about 10% reduction in nutrient loads from 1984 to 2010, closely related to the decrease in agricultural land. However, without calibration and validation, the simulated reduction in the sediment and nutrient loads may be problematic because SWAT mainly simulates the static LULC patterns, whereas LULC transitions, such as construction phases, may generate more sediment and nutrient loads. In addition, the simulation also did not account for the sediment and nutrients generated from stream bank erosion.  相似文献   

10.
密云水库上游不同土地利用方式下的土壤侵蚀特征   总被引:2,自引:1,他引:2  
[目的]为了合理配置北京密云水库水土流失重点治理区的水土保持综合措施。[方法]基于石匣小流域坡面径流小区定位观测资料,分析了不同土地利用方式及水土保持措施的坡面土壤侵蚀特征。[结果](1)5种土地利用方式的土壤侵蚀量差异明显,与裸地相比较,耕地、人工草地、封禁荒草地和林地的减沙率达63.88%~99.63%;(2)梯田比坡耕地措施小区的土壤侵蚀量减少了95.62%,起到了显著的水土保持作用;(3)采用水平条和鱼鳞坑措施林地小区的减沙率分别为83.56%和96.53%,具有十分明显的减蚀作用;(4)与人工草地相比较,封禁荒草地的侵蚀产沙量减少了98.25%,可以有效地控制水土流失。[结论]增加地表植被覆盖,减少人为干扰以及合适地配置梯田、鱼鳞坑和水平条等水土保持工程措施具有良好的水土保持作用。  相似文献   

11.
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   

12.
黄土丘陵区淤地坝建设后小流域泥沙拦蓄与输移特征   总被引:4,自引:2,他引:2  
了解淤地坝建设后小流域泥沙拦蓄与输移的变化特征对正确认识和评价淤地坝的减蚀作用有重要意义.该文通过对黄土丘陵区王茂沟流域1953-2015年不同时段内淤地坝的拦沙量和流域出口输沙量的分析,研究了坝系建设后泥沙拦蓄、输移和侵蚀的变化过程与特征.研究表明,王茂沟流域年均拦沙模数呈减少-增加-再减少的波动变化趋势;流域年均输沙模数呈先增加后减少的变化趋势;1953-1986年期间,不同阶段的年均侵蚀模数变化不大,1987年后呈显著下降趋势.流域治理后期与初期相比,年均拦沙模数、输沙模数和侵蚀模数分别下降了79.3%、90.6%和83.9%.淤地坝建设初期,有效库容对流域拦沙模数和输沙模数的变化有重要影响,侵蚀性降雨频发和较低的水土流失治理度是侵蚀强烈的主要因素;流域治理后期,侵蚀性降雨及其发生频次的减少,水土流失治理度的提高与稳固,是流域拦沙、输沙和侵蚀产沙显著下降的主要原因.淤地坝在控制流域侵蚀产沙、减少泥沙输移方面作用显著,但要达到持续有效的作用,坡面治理不容忽视,两者兼顾是黄土丘陵区水土保持的必由之路.  相似文献   

13.
甘肃天水市对比小流域暴雨洪水侵蚀产沙特性   总被引:1,自引:0,他引:1       下载免费PDF全文
 为分析黄土丘三区水土保持综合治理对小流域典型暴雨产汇流特性的影响,依据桥子东、西沟对比小流域暴雨洪水泥沙观测资料,结合实地调查对比分析雨、洪、沙特性。结果表明:在降雨差异很小的情况下,其水沙特性差异明显,桥子东沟较西沟洪峰削减率达66.9%,单位面积减洪量1万3336m3/km2,减沙量8534t/km2,2流域的流量和含沙量过程变化趋势基本一致,但西沟变率均大于东沟,且西沟流域侵蚀模数是东沟的3.5倍。桥子东沟流域各项水土保持措施发挥了显著的蓄洪拦沙作用,减洪效益59.9%,减沙效益79.5%;桥子西沟的林草措施减洪效益为6.9%,减沙效益8.4%。  相似文献   

14.
以称钩河坝系流域降水、径流、泥沙和水土保持措施的5 a监测统计数据为依据,Quick Bird卫星影像为主要数据源,在ArcGIS 9.3及Region Manager 5.5软件支持下,研究该坝系流域降雨变化和水保措施对径流和产沙量变化的影响,分析坝系水土保持措施拦沙效益。结果表明:2007—2011年间,水土保持措施建设是该流域径流和侵蚀产沙减少的主要原因,其中坡面治理措施面积增加133.04 hm2,坝系流域总控制面积达到8 843.58 hm2,占流域总面积的54.80%。坝控范围内年平均侵蚀模数为18.80 t/km2,侵蚀模数减少5 581.20 t/km2。  相似文献   

15.
Soil erosion from agricultural fields is a worldwide problem, to influence water quality, soil fertility and reservoir sedimentation especially in Mediterranean countries such as Morocco. In fact, this work assesses the effects of Best Management Practices (BMPs) on sediments using the Soil and Water Assessment Tool (SWAT) model in the Kalaya watershed in Northern Morocco, to recommend the most appropriate practice. This study is based on the use of three most usable practices: contouring, strip-cropping and terracing, by the calibrated SWAT model. The general parameters of the model have been modified to reflect the implementation of different agricultural BMPs used. Resulting sediment yield were compared with the baseline scenario, for validation. However, the effective measures to reduce sediment losses at the watershed level are organized according to their effectiveness, and these are terracing (28% reduction and the value is 15t/ha/yr) followed by strip-cropping (9% reduction and the value is 5t/ha/yr). In contrast, measurements performed by the contouring are inappropriate for the study area because they have contributed to increasing the soil erosion (more than 31% of losses and the value is 17t/ha/yr more than existing conditions). Therefore, the model illustrates that the terrace is effective for reducing sediment losses and limiting soil erosion especially on steep slopes. Thus, the results provide useful information for targeted management in order to implement the most effective agricultural BMPs in the watershed.  相似文献   

16.
《CATENA》2005,64(1):61-80
Accelerated soil erosion is a worldwide problem because of its economic and environmental impacts. To effectively estimate soil erosion and to establish soil erosion management plans, many computer models have been developed and used. The Revised Universal Soil Loss Equation (RUSLE) has been used in many countries, and input parameter data for RUSLE have been well established over the years. However, RUSLE cannot be used to estimate the sediment yield for a watershed. Thus, the GIS-based Sediment Assessment Tool for Effective Erosion Control (SATEEC) was developed to estimate soil loss and sediment yield for any location within a watershed using RUSLE and a spatially distributed sediment delivery ratio. SATEEC was enhanced in this study by developing new modules to: 1) simulate the effects of sediment retention basins on the receiving water bodies, 2) estimate the sediment yield from a single storm event, and 3) prepare input parameters for the Web-based sediment decision support system using a GIS interface. The enhanced SATEEC system was applied to the study watershed to demonstrate how the enhanced system can be effectively used for soil erosion control. All the procedures are fully automated with Avenue, CGI, and database programming; thus the enhanced SATEEC system does not require experienced GIS users to operate the system. This easy-to-operate SATEEC system can be used to identify areas vulnerable to soil loss and to develop efficient soil erosion management plans.  相似文献   

17.
 基于水土保持学基本理论并结合RS、GIS技术,以黄土高塬沟壑区典型小流域一杨家沟小流域为主要研究对象,并与未治理的小流域——董庄沟小流域进行对比,以1954—2008年的降水、径流、泥沙以及土地利用变化为基础数据,以水利部颁布的《土壤侵蚀分类分级标准》为标准,研究杨家沟小流域50多年来的土地利用变化及其对水土流失的影响。结果表明:1)杨家沟小流域自50年代初开始采取水土保持治理措施以来,土地利用发生了较大的变化,林地面积大幅增加;2)杨家沟小流域水土流失状况得到了明显改善,年产流降雨量、年径流量、年输沙量、土壤密度都明显减小,侵蚀强度分级中强烈、极强烈、剧烈侵蚀面积不断减少;3)杨家沟小流域水土流失状况虽然得到了有效控制,但还可以加大治理力度,调整土地利用类型和土地利用结构,部分坡度较大的耕地应严格退耕还林,进一步植树造林,提高未利用地利用率,更加有效地控制水土流失。  相似文献   

18.
景珂星      毛欢      宋进喜      黄鹏      吴琼      庞国伟     《水土保持研究》2023,30(1):62-69
气候变化是影响流域水文循环过程的重要驱动因素,近年来,气候变化导致极端降雨—径流事件的频繁发生对人类社会经济发展构成了严重的威胁。因此,迫切需要开展流域水文模拟和产流特征分析。土壤和水评估工具(SWAT)是一种具有物理机制的分布式水文模型,已被广泛用于评价变化环境下的水文过程。以黄土高原岔巴沟流域为研究区,通过利用与黄土高原地区产流模式更为接近的Green-Ampt下渗法驱动SWAT模型模拟了岔巴沟流域日尺度的水文过程,并以水文响应单元为分析对象,结合4个降雨—径流事件的地表产流量和地表径流系数分析了降雨强度和前期土壤含水量对不同土地覆被产流特征的影响。结果表明:(1)基于Green-Ampt下渗法驱动的SWAT模型率定期和验证期ENS为0.76,0.74,R2为0.78,0.75,模型能够较好地模拟日尺度流域水文过程;(2)流域不同土地覆被下地表径流系数随最大雨强的增加呈显著上升趋势,且最大降雨强度大于16 mm/h后地表径流系数显著增加,当土地覆被为耕地时降雨转化为地表径流的比例最大,其次为草地和林地;(3)前期土壤含水量的大小可以揭示大...  相似文献   

19.
锡林郭勒平原水土流失浅析   总被引:1,自引:0,他引:1  
锡林郭勒平原水土流失浅析甄国志(内蒙古锡林郭勒盟水土保持站,锡林浩特市026000)蓝天白云,绿草红花,空中百鸟飞,草地遍牛羊。这是诗人、画家对昔日锡林郭勒草原美丽富饶的赞美,同时也确实是昔日锡林郭勒草原的真实写照。现在,锡林郭勒草原已严重退化,严重...  相似文献   

20.
The severity of soil erosion is considered to vary according to the structure of the bench terrace and the ground cover conditions. Erosion losses were investigated in a field experiment based on 20 m × 5 m erosion plots on a 21 per cent slope in Southern China. Five plots were established for the present study. Rainfall, runoff and sediment yield from plots were recorded for 5 years (2001–2005) and which five different types of terraces on sloping red soil were compared. The results show that the planting of grass on the riser is the most important factor affecting runoff and sediment yield, the next most important factor was the construction of a bund built on the edge of the terrace. Although the terrace bed slope (slope < 5 degrees) does not significantly affect the runoff, it does benefit the soil. A terrace combined with vegetation measures is effective in controlling runoff and soil erosion. Among various terraces, the level terrace (i.e. grass planted on the riser and bunds built on the edge of a bench terrace) is apparently the most beneficial for soil conservation purposes, indicating that this type is an excellent choice for conserving soil and water resources in sloping red soil in Southeastern China. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

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