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水土保持在维护区域生态安全中具有重要作用.“5.12”汶川地震中,茶坪山区域水土保持功能严重受损,经过4年时间,其恢复效果及变化趋势如何,是决策者迫切需要的重要信息.利用TM影像,解译了研究小流域2007、2008、2011年地震前后3个时段的土地利用图.基于GIS和RS,利用RUSLE模型分别计算了3个时段土壤侵蚀量和侵蚀强度.通过对比,分析了水土保持功能恢复效应.结果表明:总面积474.41km2的研究区内,2007年土壤侵蚀总量4.061×105t,2008年土壤侵蚀总量6.997×105t,增加了72.30%.2011年土壤侵蚀总量6.163×105t,相比2008年,土壤侵蚀总量减少了11.92%,水土保持功能有所恢复.分析发现,地震前后3个年份各侵蚀强度级别的面积都是随侵蚀强度的增加而减少,说明地震破坏及恢复期,土壤侵蚀强度的面积分布格局并未改变. 相似文献
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Biodiversity conservation has undergone a profound change in philosophy, policies and management approaches over the last
forty years. The traditional top–down approach to nature protection has been widely criticized for failing to include critical
social elements in management practices, and is being gradually replaced by a slew of participatory strategies under the rubric
of bottom-up conservation. The new approach recognizes local communities as key partners in wildlife management and seeks
their participation in social development and biodiversity conservation. However, every social context is different in its
structure and functions, and in the way social groups respond to calls for participation. In order to gain a better understanding
of the approach and the barriers encountered in its implementation, a questionnaire survey of 188 households was employed
in the communities of the Upper Mustang extension of Annapurna Conservation Area (ACA) in Nepal. The study provides a comparative
analysis of community participation and its barriers between Non-Tourist (NT) and Tourist (TV) villages. The results revealed
important differences between the two groups in terms of their participation in community programs, barriers to participation,
and perception of benefits from participation. Owing to their distinct spatial, demographic and attitudinal differences, the
two village groups have their own sets of needs, values and motivation factors which cannot be generalized and treated as
such. The research clearly identifies the need for the conservation agency to be creative in devising strategies and initiatives
appropriate to specific social groups so as to optimize their input in participatory conservation. 相似文献
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In this article we compared the response of surface water runoff to a storm event for different rates of urbanization, reforestation
and riparian buffer setbacks across forty subwatersheds of the Muskegon River Watershed located in Michigan, USA. We also
made these comparisons for several forecasted and one historical land use scenarios (over 140 years). Future land use scenarios
to 2040 for forest regrowth, urbanization rates and stream setbacks were developed using the Land Transformation Model (LTM).
Historical land use information, from 1900 at 5-year time step intervals, was created using a Backcast land use change model
configured using artificial neural network and driven by agriculture and housing census information. We show that (1) controlling
the rate of development is the most effective policy option to reduce runoff; (2) establishing setbacks along the mainstem
are not as effective as controlling urban growth; (3) reforestation can abate some of the runoff effects from urban growth
but not all; (4) land use patterns of the 1970s produced the least amount of runoff in most cases in the Muskegon River Watershed
when compared to land use maps from 1900 to 2040; and, (5) future land use patterns here not always lead to increased (worse)
runoff than the past. We found that while ten of the subwatersheds contained futures that were worse than any past land use
configuration, twenty-five (62.5%) of the subwatersheds produced the greatest amount of runoff in 1900, shortly after the
entire watershed was clear-cut. One third (14/40) of the subwatersheds contained the minimum amount of runoff in the 1960s
and 1970s, a period when forest amounts were greatest and urban amounts relatively small. 相似文献
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Community capacity for watershed management has emerged as an important topic for the conservation of water resources. While much of the literature on community capacity has focused primarily on theory construction, there have been few efforts to quantitatively assess community capacity variables and constructs, particularly for watershed management and conservation. This study seeks to identify predictors of community capacity for watershed conservation in southwestern Illinois. A subwatershed-scale survey of residents from four communities located within the Lower Kaskaskia River watershed of southwestern Illinois was administered to measure three specific capacity variables: community empowerment, shared vision and collective action. Principal component analysis revealed key dimensions of each variable. Specifically, collective action was characterized by items relating to collaborative governance and social networks, community empowerment was characterized by items relating to community competency and a sense of responsibility and shared vision was characterized by items relating to perceptions of environmental threats, issues with development, environmental sense of place and quality of life. From the emerging factors, composite measures were calculated to determine the extent to which each variable contributed to community capacity. A stepwise regression revealed that community empowerment explained most of the variability in the composite measure of community capacity for watershed conservation. This study contributes to the theoretical understanding of community capacity by quantifying the role of collective action, community empowerment and shared vision in community capacity, highlighting the need for multilevel interaction to address watershed issues. 相似文献
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达县百节"水保生态园区"水土流失治理与生态环境保护 总被引:1,自引:1,他引:1
本文反映了严重的水土流失是导致达县百节河小流域生态环境恶化的主要原因。阐述了通过实施水土流失治理三大措施:工程措施、生物措施、农耕措施,有效地控制了水土流失等生态问题,极大地改善了当地生态环境,取得了显著的三大效益:经济效益、生态效益和社会效益。同时陈述了百节河小流域生态园区的建设特色:组织协调部门资金捆绑使用,集中投入:业主参与,责、权、利统一,投资渠道多元化,为水土保持和生态环境建设注入了生机与活力。 相似文献
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水土保持对维持良好的水库水生态环境具有重要的影响.生态修复技术作为一种新的水土保持措施,可实现受损水库生态环境的修复.围绕水库消落带、水库涵养林、库区耕地和水库水环境等方面来研究生态修复技术在水库水土保持中的应用情况. 相似文献
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Sanjiv Kumar Venkatesh Merwade 《Journal of the American Water Resources Association》2009,45(5):1179-1196
Abstract: Impact of watershed subdivision and soil data resolution on Soil Water Assessment Tool (SWAT) model calibration and parameter uncertainty is investigated by creating 24 different watershed model configurations for two study areas in northern Indiana. SWAT autocalibration tool is used to calibrate 14 parameters for simulating seven years of daily streamflow records. Calibrated parameter sets are found to be different for all 24 watershed configurations, however in terms of calibrated model output, their effect is minimal. In some cases, autocalibration is followed by manual calibration to correct for low flows, which were underestimated during autocalibration. In addition to normal validation using four years of streamflow data for each calibrated parameter set, cross‐validation (using a calibrated parameter set from one model configuration to validate observations using another configuration) is performed to investigate the effect of different model configurations on streamflow prediction. Results show that streamflow output during cross‐validation is not affected, thus highlighting the non‐unique nature of calibrated parameters in hydrologic modeling. Finally, parameter uncertainty is investigated by extracting good parameter sets during the autocalibration process. Parameter uncertainty analysis suggests that significant parameters show very narrow range of uncertainty across different watershed configurations compared with nonsignificant parameters. Results from recalibration of some configurations using only six significant parameters were comparable to that from calibration using 14 parameters, suggesting that including fewer significant parameters could reduce the uncertainty arising from model parameters, and also expedite the calibration process. 相似文献
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Non-point-source (NPS) pollution remains the primary source of stream impairment in the United States. Many problems such
as eutrophication, sedimentation, and hypoxia are linked with NPS pollution which reduces the water quality for aquatic and
terrestrial organisms. Increasingly, NPS pollution models have been used for landscape-scale pollution assessment and conservation
strategy development. Our modeling approach functions at a scale between simple landscape-level assessments and complex, data-intensive
modeling by providing a rapid, landscape-scale geographic information system (GIS) model with minimal data requirements and
widespread applicability. Our model relies on curve numbers, literature-derived pollution concentrations, and land status
to evaluate total phosphorus (TP), total nitrogen (TN), and suspended solids (SS) at the reach scale. Model testing in the
Chesapeake Bay watershed indicated that predicted distributions of water quality classes were realistic at the reach scale,
but precise estimates of pollution concentrations at the local scale can have errors. Application of our model in the tributary
watersheds along Lake Ontario suggested that it is useful to managers in watershed planning by rapidly providing important
information about NPS pollution conditions in areas where large data gaps exist, comparisons among stream reaches across numerous
watersheds are required, or regional assessments are sought. 相似文献
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Assessment of Water Supply as an Ecosystem Service in a Rural-Urban Watershed in Southwestern Mexico City 总被引:1,自引:0,他引:1
Jujnovsky J González-Martínez TM Cantoral-Uriza EA Almeida-Leñero L 《Environmental management》2012,49(3):690-702
Studies from the ecosystem services perspective can provide a useful framework because they allow us to fully examine the
benefits that humans obtain from socio-ecological systems. Mexico City, the second largest city in the world, has faced severe
problems related to water shortages, which have worsened due to increasing population. Demand for space has forced changes
in land cover, including covering areas that are essential for groundwater recharge. The city has 880 km2 of forest areas that are crucial for the water supply. The Magdalena River Watershed was chosen as a model because it is
a well-preserved zone within Mexico City and it provides water for the population. The general aim of this study was to assess
the ecosystem service of the water supply in the Magdalena River Watershed by determining its water balance (SWAT model) and
the number of beneficiaries of the ecosystem services. The results showed that the watershed provides 18.4 hm3 of water per year. Baseflow was dominant, with a contribution of 85%, while surface runoff only accounted for 15%. The zone
provides drinking water to 78,476 inhabitants and could supply 153,203 potential beneficiaries. This work provides an example
for understanding how ecosystem processes determine the provision of ecosystem services and benefits to the population in
a rural–urban watershed in Mexico City. 相似文献
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浅谈开发建设项目水土保持方案的编制 总被引:1,自引:0,他引:1
依据有关水土保持法律法规和技术规范,简明阐述了开发建设项目水土保持方案编制的有关规定和水土保持方案的主要工作内容,旨在宣传水保法规、推动我区水土保持,尤其是开发建设项目水土保持方案工作,为提高社会各界水土保持意识提供信息 相似文献
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An Integrated WebGIS Framework for Volunteered Geographic Information and Social Media in Soil and Water Conservation 总被引:1,自引:0,他引:1
Volunteered geographic information and social networking in a WebGIS has the potential to increase public participation in
soil and water conservation, promote environmental awareness and change, and provide timely data that may be otherwise unavailable
to policymakers in soil and water conservation management. The objectives of this study were: (1) to develop a framework for
combining current technologies, computing advances, data sources, and social media; and (2) develop and test an online web
mapping interface. The mapping interface integrates Microsoft Silverlight, Bing Maps, ArcGIS Server, Google Picasa Web Albums
Data API, RSS, Google Analytics, and Facebook to create a rich user experience. The website allows the public to upload photos
and attributes of their own subdivisions or sites they have identified and explore other submissions. The website was made
available to the public in early February 2011 at and evaluated for its potential long-term success in a pilot study. 相似文献
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Cost‐Effective Placement of Best Management Practices in a Watershed: Lessons Learned from Conservation Effects Assessment Project
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Lyubov A. Kurkalova 《Journal of the American Water Resources Association》2015,51(2):359-372
This article reviews the key, cross‐cutting findings concerning watershed‐scale cost‐effective placement of best management practices (BMPs) emerging from the National Institute of Food and Agriculture Conservation Effects Assessment Project (CEAP) competitive grants watershed studies. The synthesis focuses on two fundamental aspects of the cost‐effectiveness problem: (1) how to assess the location‐ and farmer‐specific costs of BMP implementation, and (2) how to decide on which BMPs need to be implemented and where within a given watershed. Major lessons learned are that (1) data availability remains a significant limiting factor in capturing within‐watershed BMP cost variability; (2) strong watershed community connections help overcome the cost estimation challenges; (3) detailing cost components facilitates the transferability of estimates to alternative locations and/or economic conditions; and (4) implicit costs vary significantly across space and farmers. Furthermore, CEAP studies showed that (5) evolutionary algorithms provide workable ways to identify cost‐effective BMP placements; (6) tradeoffs between total conservation costs and watershed‐scale cost‐effective water quality improvements are commonly large; (7) quality baseline information is essential to solving cost‐effectiveness problem; and (8) systemic and modeling uncertainties alter cost‐effective BMP placements considerably. 相似文献
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Quantifying the Effects of Conservation Practices on Soil,Water, and Nutrients in the Loess Mesa Ravine Region of the Loess Plateau,China 总被引:1,自引:0,他引:1
A large number of soil and water conservation programs have been implemented on the Loess Plateau of China since the 1950s.
To comprehensively assess the merits and demerits of the conservation practices is of great importance in further supervising
the conservation strategy for the Loess Plateau. This study calculates the impact factors of conservation practices on soil,
water, and nutrients during the period 1954–2004 in the Nanxiaohegou Catchment, a representative catchment in the Loess Mesa
Ravine Region of the Loess Plateau, China. Brief conclusions could be drawn as follows: (1) Soil erosion and nutrient loss
had been greatly mitigated through various conservation practices. About half of the total transported water and 94.8 % of
the total transported soil and nutrients, had been locally retained in the selected catchment. The soil retained from small
watersheds do not only form large-scale fertile farmland but also safeguard the Yellow River against overflow. (2) Check dam
was the most appropriate conservation practice on the Loess Plateau. In the selected catchment, more than 90 % of the retained
soil and water were accomplished by the dam farmland, although the dam farmland occupied only 2.3 % of the total area of all
conservation measures. Retention abilities of the characteristic conservation practices were in the following order: dam farmland > terrace
farmland > forest land and grassland. (3) The conservation practices were more powerful in retaining sediment than in reducing
runoff from the Loess Plateau, and the negative effects of the conservation practices on reducing water to the Yellow River
were relatively slight. 相似文献
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