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1.
Both permit requirements and ecological assessments have been used to evaluate mitigation success. This analysis combines these two approaches to evaluate mitigation required under Section 404 of the United States Clean Water Act (CWA) and Section 10 of the Rivers and Harbors Act, which allow developers to provide compensatory mitigation for unavoidable impacts to wetlands. This study reviewed permit files and conducted field assessments of mitigation sites to evaluate the effectiveness of mitigation required by the US Army Corps of Engineers for all permits issued in Orange County, California from 1979 through 1993. The 535 permit actions approved during this period allowed 157 ha of impacts. Mitigation was required on 70 of these actions, with 152 ha of enhanced, restored, and created habitat required for 136 ha of impacts. In 15 permit actions, no mitigation project was constructed, but in only two cases was the originally permitted project built; the two cases resulted in an unmitigated loss of 1.6 ha. Of the remaining 55 sites, 55% were successful at meeting the permit conditions while 11% failed to do so. Based on a qualitative assessment of habitat quality, only 16% of the sites could be considered successful and 26% were considered failures. Thus, of the 126 ha of habitat lost due to the 55 projects, only 26 ha of mitigation was considered successful. The low success rate was not due to poor enforcement, although nearly half of the projects did not comply with all permit conditions. Mitigation success could best be improved by requiring mitigation plans to have performance standards based on habitat functions.  相似文献   

2.
Sustainable urban water infrastructure planning is vital for all cities in developing countries, where rapid urbanization has exacerbated the increasingly burdened environment. Water sustainability is a prerequisite for economic growth, social equity, and living quality in urban areas. This paper documents the current challenges and summarizes the solutions adopted in water infrastructure planning and management. Then, case studies of how multilateral financial institutions have promoted sustainable water infrastructure planning through economic appraisal and the novel approaches adopted for sustainable water infrastructure planning and asset management, are presented for the three cities of Jiaozhou, Cixi, and Fangchenggang. Conclusions are made based on the comparison and analysis of the experiences drawn from the case studies of how economic analysis could help promote sustainable water infrastructure planning and management. It is illustrated that economic analysis that considers ecosystem services supply should be employed more in water infrastructure planning, operation, and management in China.  相似文献   

3.
A methodology is described that allows determination of instream flow requirements for maintenance of riparian trees. Tree-ring data revealed strong relationships between tree growth and stream flow volume for riparian species at Rush Creek, an alluvial stream within an arid setting; these relationships allowed development of models that predict growth rates from hydrologic variables. The models can be used to assess instream flow requirements under the assumption that certain levels of growth are necessary to maintain the population. There is a critical need for development and use of instream flow methodologies for riparian vegetation, since present methodologies focus on needs of aquatic animals (e.g., fish) and may underestimate needs of the entire riparian ecosystem.  相似文献   

4.
Summary Among the different impacts of coastal tourism on the environment, the effect of tourism on public health has special importance. The large increase in population during the high season results usually in an increase in the amount of waste water produced. If the necessary infrastructure for handling these wastes is not available, the sea is polluted, causing serious problems.To investigate the effects of sea pollution on the public, a health survey was conducted in Bodrum and Çesme, the two most important tourist coastal resorts of Turkey. A questionnaire about the health problems which tourists suffer, as well as their culinary habits, swimming habits,etc. was distributed. At the same time the pollution level in the sea was determined in the form of coliform concentration. As a result it is shown that those swimming in polluted waters suffer more from gastro-intestinal diseases than others. Furthermore, foreigners (usually Scandinavians) and children are proved to be more susceptible to pollution, possibly due to their lack of immunity.Dr Günay Kocasoy is presently Associate Professor in the Department of Chemical Engineering at Bogaziçi University. Her fields of interest are in environmental engineering, water pollution and marine sciences. She obtained a BS degree in Chemical Engineering from Robert College, Istanbul, Turkey, and subsequently a BA in Industrial Administration from Franklin University, Columbus, Ohio, USA. Following more recent studies she possesses both an MS and a PhD in Marine Sciences from Istanbul University.  相似文献   

5.
In California, the growing popularity of urban agriculture (UA) has unfolded against a backdrop of historic drought. While UA is often celebrated as an urban sustainability strategy, it must be able to persist during drought if it is to perform these functions. Using Santa Clara County – the geographic core of Silicon Valley – as a case study, we use interviews and surveys to explore the implications of drought for UA. We show how developing an understanding of water access for UA during a drought requires examining the social and institutional context of water management and use. In metropolitan California, the highly decentralised water supply system combined with the diverse institutional arrangements that support UA create an uneven landscape of water access. Consequently, the pressure to change water-consuming practices – that is, the stress that institutional drought responses place on different water users – is geographically and socially differentiated. Among UA water users, responses to drought have also varied, in part because the possibilities for change are constrained by the sociotechnical arrangements of UA sites and the different purposes of UA.  相似文献   

6.
Devils Lake, located in a closed basin in northeastern North Dakota has over a century-long history of highly fluctuating water levels. The lake has risen nearly 25 feet (7.7 m) since 1993, more than doubling its surface area. Rising water levels have affected rural lands, transportation routes, and communities near the lake. In response to rising lake levels, Federal, state and local agencies have adopted a three-part approach to flood damage reduction, consisting of (1) upper basin water management to reduce the amount of water reaching the lake, (2) protection for structures and infrastructure if the lake continues to rise, and (3) developing an emergency outlet to release some lake water. The purpose of this study was to provide information about the net regional economic effects of a proposed emergency outlet for Devils Lake. An input-output model was used to estimate the regional economic effects of the outlet, under two scenarios: (1) the most likely future situation (MLS) and (2) a best case situation (BCS) (i.e., where the benefits from the outlet would be greatest), albeit an unlikely one. Regional economic effects of the outlet include effects on transportation (road and railroad construction), agriculture (land kept in production, returned to production sooner, or kept in production longer), residential relocations, and outlet construction expenditures. Effects are measured as changes in gross business volume (gross receipts) for various sectors, secondary employment, and local tax collections. The net regional economic effects of the proposed outlet would be relatively small, and consideration of these economic impacts would not strengthen the case for an outlet.  相似文献   

7.
The Water Framework Directive is a major regulatory reform of water resources management within the European Union. Integrated catchment management plans must be prepared for all river basins, in order to achieve 'good ecological status' in all EU waters. Ecological status is a broader measure of water quality than the chemical and biological measures that were previously dominant. The Directive calls for a consideration of the economic costs and benefits of improvements to ecological status. In this paper, we use the choice experiment method to estimate the value of improvements in three components of ecological status. Given the high resource cost of valuation studies, benefits transfer methods will be needed in implementing the Directive. We thus also test the ability of choice experiments for benefits transfer across two very similar rivers in the UK.  相似文献   

8.
The recently developed type transfer function (TTF) simulation approach was applied to generate a regional-scale nonpoint-source ground water vulnerability assessment for the San Joaquin Valley, California. The computationally comparatively inexpensive TTF approach produces quantitative estimates of contaminant concentrations for large regional scales through characteristic functions based on different soil textures and their leaching properties. The TTF simulations employed an extensive soil and recharge database to estimate atrazine (1-chloro-3-ethylamino-5-isopropylamino-2,4,6-triazine) concentrations at a compliance depth of 3 m resulting from a surface application. Two different sets of TTFs with two different levels of upscaling were used for spatially uniform and distributed recharge estimates. Results show that estimated atrazine concentrations can be related to soil survey information. Areas with high potential vulnerability to atrazine leaching were found for soils with low organic carbon content and sandy loam and loam textures. Travel times for atrazine peak concentrations to the compliance depth ranged from 350 to 730 d. The extent of areas with estimated atrazine concentrations above the maximum contaminant level was less extensive when uniform annual recharge values were used. Simulated TTF concentrations were highest for eastern Fresno County, a vulnerability pattern that is also supported by field observations. The TTF modeling approach is shown to be a useful tool for quantitative pesticide leaching estimates at regional scales significantly larger than those of previous studies.  相似文献   

9.
10.
Increasing salinity is one of the most significant and widespread forms of groundwater pollution in coastal areas. This paper presents the causes and impacts of saline water intrusion in coastal areas. Various causes of salt water intrusion, and approaches for the determination of its extent and various measures to control the salt water intrusion are described. An aquifer performance test (APT) approach is presented to identify the extent of existing salt water intrusion in the study area located in the southwest coastal region of Gujarat State (India). A resistivity based experimental technique is used to identify the quality of the groundwater available at different depths. A methodology is presented to assess the extent of available fresh and saline groundwater and to find out the limit up to which lower saline groundwater can be withdrawn for industrial purposes without affecting the upper fresh water layer which can be made available for domestic purposes.  相似文献   

11.
During oil and gas production, water is often extracted from geological formations along with the hydrocarbons. These "produced waters" have been discharged to Nueces Bay since the turn of the century. These effluents were found to be highly toxic, and sediments in the vicinity of the discharges were also toxic. We developed a map of wells and produced-water discharge sites in the vicinity of Nueces Bay and identified numerous unplugged wells suitable for conversion to produced water disposal wells. An economic analysis of conversion to subterranean injection of produced water indicates that most of the wells currently in production could pay out the cost of conversion to injection in one to three years. The use of one injection well for two or more water-producing wells could yield greater savings. Wells that could not support the cost of injection are small producers, and their loss would not constitute a major loss of jobs or dollars to the area. This study could serve as a useful model for evaluating the economic feasibility of conversion to injection in other areas of Texas and Louisiana.  相似文献   

12.
The challenges faced by coastal protected areas in both promoting highly attractive sites and preserving the natural attributes of these sites have been given a new dimension with the opportunities presented by ecotourism. Realising the market potential of a protected area and, at the same time, conserving the unique features of an area is a difficult task. This paper explores the possibilities that backpacker tourism may offer the Quarantine Station in Sydney Harbour National Park, in Australia. The Quarantine Station is a significant cultural heritage site that is located in a sensitive coastal national park within Sydney's metropolitan area.  相似文献   

13.
何爱兰 《四川环境》2005,24(3):49-51
无公害产品产地农业生态环境质量是影响无公害产品质量的重要因子之一,对丽水市庆元县甜桔柚基地农业环境质量的调查和监测表明,庆元县无公害甜桔柚基地符合无公害产品的环境质量要求。  相似文献   

14.
Water scarcity has become a key issue in water management. There are two contrasting positions regarding scarcity as a source of conflict or cooperation. Accordingly, it is worth exploring what exactly are the conditions that make water scarcity a source of conflict or cooperation. The history of water conflicts has shown that people are more likely to kill around a water hole than when conflicts grow into national or international issues. This suggests that there may be an inverse relationship between the level of violence and the scale at which the water conflict takes place. A common problem in environmental management has been the lack of effective mechanisms to handle conflict. In the majority of these cases, the main shortcoming was an inability of the parties to identify their differences. Therefore, this research explores the idea that understanding the causes of conflict from the outset, followed by an evaluation, at the local scale, of the conditions, is a necessary precondition to finding appropriate and sustainable solutions. With this background in mind, the objective of this paper is to employ a conflict assessment process in order to explore to the extent to which a collaborative dialogue among stakeholders can be an appropriate approach to conflict resolution. A case study in Mexico is employed as a testing ground.  相似文献   

15.
The impact of timber management and land-use change on forage production, turkey and deer abundance, red-cockaded woodpecker colonies, water yield, and trout abundance was projected as part of a policy study focusing on the southern United States. The multiresource modeling framework used in this study linked extant timber management and land-area policy models with newly developed models for forage, wildlife, fish, and water. Resource production was integrated through a commonly defined land base that could be geographically partitioned according to individual resource needs. Resources were responsive to changes in land use, particularly human-related, and timber management, particularly the harvest of older stands, and the conversion to planted pine.  相似文献   

16.
Public participation as a means of identifying sustainability indicators for Chongming County, Shanghai, China was evaluated by an international group drawing on established best practice. An initial 'long list' of 86 sustainability indicators, based on previous indicator systems developed in China, was identified. This 'long list' was reduced via consultations with local academics and local-government officers from Shanghai City and Chongming County to a 'short list' of 17 indicators. This short-list was subjected to further community consultation involving 159 local-government officers, teachers, students (aged 12-14 years), farmers and workers. Data from the consultations indicated differences in the understanding of sustainable development among the different sectors. By combining the data from the different sectors it was possible to identify a consensus around 4 core and 7 additional indicators. These are proposed as indicators which could be used to steer local activities directed towards sustainable development. The list of indicators produced by the people of Chongming Island was compared to local indicator systems in Europe. In comparison with European lists the Chongming list was found to have a greater emphasis on economic development but a similar level of concern for environmental matters. This study has special significance as it reports on the implementation of a process involving local resident participation in the process of sustainable development in China.  相似文献   

17.
The sustainability concept applied to human activities implies the need to harmonise the protection of environment with a satisfactory economic and social development. This is particularly true for tourism development: a misuse of the natural resources can cause a degradation of the tourist appeal of the destination, bringing it finally to its economic decline. This problem is particularly important in coastal tourism destinations. The implementation of an environmental management system is a powerful way for progressing towards better environmental performances. In this paper, the main results obtained in applying the Eco-Management and Audit Scheme procedure to the municipality of Cervia, a well-known tourist destination located on the Adriatic coast of Italy are described. This research puts into evidence that the main environmental pressures in the summer season are related to the supply of potable water, the production of solid wastes and wastewater air pollution and noise, etc. However, if correctly planned and managed, tourism can also contribute to environmental protection, to the conservation of biodiversity and to a sustainable use of natural resources.  相似文献   

18.
The purpose of this project was to assess the effect of estimating total suspended solids (TSS) concentrations from turbidity on TSS loads for streams in the Robeson Creek watershed. Discharge was monitored continuously and base‐flow grab and storm event composite samples were collected and analyzed for TSS and turbidity from five sites during five years of monitoring. For base‐flow samples, the TSS‐turbidity relationship for all five sites was poor indicating that TSS concentrations in base flow cannot be estimated from a TSS‐turbidity relationship. To test the effect of analyzing fewer samples, TSS from every third and the first 20 samples collected from each site was used to develop TSS‐turbidity relationships. In addition, the TSS‐turbidity relationship developed from the most downstream site was used to estimate TSS concentrations from turbidity measured at the other four sites. For four of the five sites, analyzing every third sample for TSS and using the TSS‐turbidity relationship to estimate the missing TSS concentrations would result in mean TSS loads that were not significantly different from the observed. Using the TSS‐turbidity relationship from the outlet to estimate TSS from turbidity measured at the other four sites resulted in significantly different mean TSS loads at three of the four sites. These results indicate that estimating TSS concentrations from turbidity using a TSS‐turbidity relationship developed from a subset of the overall dataset should be done with great caution.  相似文献   

19.
The Sloping Land Conversion Program (also known as "Grain for Green" or the Upland Conversion Program) for converting cropland to forest is one of China's most ambitious environmental initiatives, and is one of the world's largest land-conservation programs with a budget of RMB 337 billion (over US$ 40 billion). Although environmental impacts have played a vital role in the general reasoning and argumentation for forest plantations, environmental impact analyses have often received less attention than economic analyses in the planning of plantation forestry projects. The overall goal of this paper is to evaluate the program's environmental impact considering the farmer's interests and the potential social benefits due to carbon sequestration in different scenarios based on household and field survey data in Dunhua County. Our findings are that: (1) in many cases, the program did not give adequate consideration to land productivity and environmental heterogeneity when selecting plots; (2) more than half of the reforestation plots were on flat cropland (slopes of less than 5 degrees ); (3) in five of the eight townships, net incomes on reforested land were substantially above or below previous crop incomes, raising questions about the efficiency of the allocation of compensation to farmers participating in the program; (4) the potential carbon co-benefit increased the NPV of the program by 5954-7009 RMB/ha. In conclusion, we recommend that more attention should be paid to the quality of reforestation programs rather than just their scale and note that consideration of potential carbon sequestration co-benefits enhances the benefits of cropland conversion programs.  相似文献   

20.
Studies of urban metabolism provide important insights for environmental management of cities, but are not widely used in planning practice due to a mismatch of data scale and coverage. This paper introduces the Spatial Allocation of Material Flow Analysis (SAMFA) model as a potential decision support tool aimed as a contribution to overcome some of these difficulties and describes its pilot use at the county level in the Republic of Ireland. The results suggest that SAMFA is capable of identifying hotspots of higher material and energy use to support targeted planning initiatives, while its ability to visualise different policy scenarios supports more effective multi-stakeholder engagement. The paper evaluates this pilot use and sets out how this model can act as an analytical platform for the industrial ecology–spatial planning nexus.  相似文献   

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