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1.
Surface water quality and its natural and anthropogenic controls in the Xiangjiang River were investigated using multivariate statistical approaches and a comprehensive observation dataset collected from 2004 to 2008. Cluster analysis (CA) grouped the 15 different sampling stations into five clusters with similar hydrochemistry characteristics and pollution levels. Four principal components (PCs), nutrients, heavy metals, natural components, and organic components, were extracted from the entire dataset. Comparison of the different regional characteristics of these four PCs revealed a decreasing trend for heavy metals and an increasing trend for organic factor on an annual scale, and the seasonal trend was only observed for natural factor. We also conducted analysis of variance (ANOVA) in combination with principal component analysis (PCA) to quantify the relative contribution of spatial and temporal variations to each of the four PCs. The results revealed that 62% of the contributions from the spatial sites were responsible for variations in heavy metals, while 83% of the contributions from the sampling time were responsible for natural variations observed. However, no significant spatial or temporal contributions were found to be responsible for the nutrient and organic variations. Finally, some suggestions regarding water management were put forward based on the current status and future trends of surface water quality in the Xiangjiang River.  相似文献   

2.
Istanbul, being one of the highly populated metropolitan areas of the world, has been facing water scarcity since the past decade. Water transfer from Melen Watershed was considered as the most feasible option to supply water to Istanbul due to its high water potential and relatively less degraded water quality. This study consists of two parts. In the first part, water quality data covering 26 parameters from 5 monitoring stations were analyzed and assessed due to the requirements of the “Quality Required of Surface Water Intended for the Abstraction of Drinking Water” regulation. In the second part, a one-dimensional stream water quality model with simple water quality kinetics was developed. It formed a basic design for more advanced water quality models for the watershed. The reason for assessing the water quality data and developing a model was to provide information for decision making on preliminary actions to prevent any further deterioration of existing water quality. According to the water quality assessment at the water abstraction point, Melen River has relatively poor water quality with regard to NH4+, BOD5, faecal streptococcus, manganese and phenol parameters, and is unsuitable for drinking water abstraction in terms of COD, PO43?, total coliform, total suspended solids, mercury and total chromium parameters. The results derived from the model were found to be consistent with the water quality assessment. It also showed that relatively high inorganic nitrogen and phosphorus concentrations along the streams are related to diffuse nutrient loads that should be managed together with municipal and industrial wastewaters.  相似文献   

3.
Management of fresh water resources meets a range of often conflicting interests. Waterways usually run across political and administrative borders and hence make management difficult and collective action politically challenging. In order to meet these challenges, multi-level bioregional approaches to water management have been called for. Such an approach is institutionalised in the EU's Water Framework Directive (WFD). This paper presents the experiences of the Morsa water sub-district in southern Norway, a pilot for implementing the WFD. The paper discusses Morsa in the light of four principles for multi-level water governance: management on a bioregional scale; polycentric governance; public participation; and an experimental approach to water governance. Contrary to widely held assumptions that collective action in polycentric networks will be difficult because actors will follow their own narrow interests, the findings demonstrate how this is not an absolute truth, and how social action cannot be fully explained by rational action theories. The analysis concludes that the relative success of Morsa relates to a complex of factors, including openness of practices and active involvement of key actors, strong but including leadership, and a knowledge based ‘hybrid’ type of multi-level network combining horizontal and vertical network governance.  相似文献   

4.
We consider how ecosystem services can be incorporated into water infrastructure planning by studying the projected deepening of the Lower Weser river channel in Germany. We recalculate the project's benefit–cost ratio by integrating the monetary value of changes in different ecosystem services, as follows: (1) the restoration costs of a mitigation measure for a loss in fresh water supply for agricultural production in the estuary region, (2) the costs of a loss in habitat services, transferring the willingness to pay from a contingent valuation study to the area assessed in the environmental impact assessment, and (3) the benefits of emissions savings induced by more efficient shipping, taking a marginal abatement cost approach. We find that including monetary values for ecosystem service changes leads to a substantial drop in the benefit–cost ratio. On this basis, we argue for a reform of the standard cost–benefit analysis to facilitate more complete welfare assessments.  相似文献   

5.
Vicuña provide an excellent case study for examining the sustainable use of wildlife outside protected areas: the community-based conservation approach. Vicuña populations in the high Andes of Argentina, Bolivia, Chile, Ecuador and Perú fell to a critically low level, but a Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) ban on trade in their fiber has seen numbers recover dramatically, and now live shearing of vicuña for a high-value international market is being promoted as a mechanism to secure both sustainable vicuña populations and local livelihoods. We used a dynamic optimization model to explore the consequences of legalizing markets, including the consequences for poaching which is critical in vicuña dynamics. Using parameters obtained from the literature and expert knowledge, we explored different scenarios for the Argentine region of Cieneguillas. Our results showed that the role of the international market is ambiguous; live shearing for an international market can provide the very best of outcomes for both vicuña and local people, with large herds generating high revenues. But an international market also creates a market for poached vicuña fiber; as a result, vicuña numbers risk once again falling to critically low levels, resulting also in minimal revenues from sale of fiber. The message for the international community is that if community-based conservation is not implemented carefully then its impact can easily be perverse.  相似文献   

6.
Marine water pollution affects many recreational sites around the world. It has impacts not only on recreational activities but also on health risks for those who come into direct contact with the water. Few economic studies have explicitly considered the health risks of bathing in polluted marine waters and none have attempted to separate health benefits from other benefits of marine water quality improvements. This paper uses stated preference techniques to separately evaluate the multiple benefits of improving the quality of marine recreational waters at the Estoril Coast in Portugal. The results indicate that health risk reductions are only a small fraction of the total social benefits of water quality improvements.  相似文献   

7.
This study aimed to unpack the dynamic proximity effects of a park on residential values in the urban regeneration context: first by the development phase of the park, and second, by specific characteristics of the residential units. The study site is the Dream Forest in Seoul, South Korea, and the study period is from 2006 to 2015. The two-fold multilevel regression analysis suggests that the Dream Forest began exerting proximity effects from the time of site acquisition by the city, which peaked at a 3.7% price increment per 100-meter distance to the park from a prototypical housing unit, soon after the public announcement of the park procurement plan. During construction, inauguration and stabilization, the effect has remained at around 3.0%. The analysis also suggests that the proximity effect applies unevenly to housing units: apartment type or older housing units are more sensitive to the externality effects than their counterparts – multifamily type or newer housing units.  相似文献   

8.
The European Landscape Convention indicates that assessment of different dimensions that exist in landscapes should be taken into account in planning. In this study, we first investigated ecological, cultural and social values as perceived by the local people in a highway-planning process in Sweden. Next, we explored which factors influenced the local people's participation in the road-planning process. We used questionnaires, planning documents and the Theory of Planned Behavior to investigate the relations between different factors and local people's participation in the planning process. The results showed that people presumed the ecological values in the landscape to be adversely affected by the new road, while the social values would remain the same. Landowners had heard of the participatory-process, but few participated. Those who lived within 300 m of the road were more active in the planning process than people living further away. The findings suggest that people living within a few hundred metres of the road should be treated as key stakeholders in the planning process. The involvement of other stakeholders, and when in the public participation process stakeholders should be involved, is also discussed.  相似文献   

9.
This study examines the effects of relocating the Flint Farmers’ Market, a large and successful market in the medium-sized legacy city of Flint, Michigan. Over the course of a year, market patrons and vendors were surveyed to explore questions about the scale of the market, patron demographics, reasons for visiting the market, seasonal variations in outcomes, and healthy food access. The results indicate that the relocated, downtown market is successful in large part because it satisfies multiple needs – it provides access to fresh, local produce; it provides lunch options for downtown workers and students; and it serves as a community gathering space. The study further demonstrates that farmers’ markets in legacy cities can serve a large region, attract diverse customers, and remain sustainable year-round, even in northern climates. These findings should be of interest to planners, policy-makers, and market managers who are considering opening or relocating a farmers’ market as a means of supporting community health, well-being, and economic development.  相似文献   

10.
ABSTRACT

An eQUEST model was developed to conduct a simulation study of a natural gas engine-driven heat pump (GEHP) for an office building in Woodstock, Ontario, Canada. Prior to the installation of the GEHP, the heating and cooling demands of the office building were provided by rooftop units (RTUs), comprising of natural gas heater and electric air conditioner. Energy consumption for both GEHP and RTUs were monitored for operation in alternating months. These recorded energy consumptions along with weather data were used in the regression analysis. The developed eQUEST models were validated and calibrated with the regression analysis results with respect to the ASHRAE Guideline 14–2014. The eventual models were then applied to investigate the potential annual energy consumption, greenhouse gas (GHG) emission and energy cost savings achieved by using the GEHP in Woodstock, and other cities in Canada, particularly in Ontario.  相似文献   

11.
One of the most important processes in an integrated waste management system is incineration, which, among the different waste management disposal options still remains a critical waste treatment system. New dynamics and approaches have to be developed to embrace such a wide and complex topic, and better knowledge and assessment of incineration are strategically significant to define future environmental scenarios.Life cycle assessment (LCA), as a tool to optimise process-operating conditions and to support decision-making process, is often applied to investigate processes under design in various sectors, since choices made in the development phases can affect the future environmental profile. However, even if the greatest opportunity to improve a process from an environmental perspective is during the design phase, at the same time the knowledge is limited, in accordance with the so-called “design paradox”.Thus, in this context, this study used LCA methodology to quantitatively assess the extent to which the environmental impact of an incineration line reflects the environmental burdens perceived during the design phase. A comparative LCA was conducted at the design phase and under operating conditions at an Italian municipal solid waste incineration plant.The outcomes of the study indicated that for almost all of the categories analysed, the impacts associated with the process under design overestimated the impacts associated with the operating process, with the exception of climate change and water depletion. The results suggested that after the conduction of an LCA at the design phase of a process, an LCA of the operative conditions should be carried out to verify how much the over- or under-estimations affected the results.  相似文献   

12.
Spain's Programa AGUA was proposed in 2004 as a replacement for the Spanish National Hydrological Plan and represented a fundamental policy shift in national water management from large inter-basin water transfers to a commitment to desalination. Twenty-one desalination facilities are planned for six provinces on the Spanish Mediterranean coast to supplement their water needs. These include the province of Almería that for the last 30 years has endured a net water abstraction overdraft leading to serious reservoir depletion and groundwater imbalances. Rising water use is a result of increasing demand to support irrigated agriculture (e.g. greenhouse horticulture) and for domestic needs (e.g. rapid urban growth and tourism development), which has led observers to question Almería's long-term water sustainability. Desalinated water alone is unlikely to be sufficient to make up these water deficits and water-users will have to accept a move to full-price water recovery by 2010 under the European Union (EU) Water Framework Directive of which Spain is a signatory. Anticipated water efficiencies resulting from higher water tariffs, increasing water reuse and water infrastructure improvements (including inter-basin transfers), in conjunction with increasing use of desalinated water, are expected to address the province's current water overdraft. However, Almería will need to balance its planned initiatives against long-term estimates of projected agricultural and domestic development and the environmental consequences of adopting a desalination-supported water future.  相似文献   

13.
The aim of the present work is to design a model for evaluating the impact of planned infrastructures on species survival at the territorial scale by calculating a connectivity index. The method developed involves determining the effective distance of displacement between patches of the same habitat, simplifying earlier models so that there is no dependence on specific variables for each species. A case study is presented in which the model was used to assess the impact of the forthcoming roads and railways included in the Spanish Strategic Infrastructure and Transport Plan (PEIT, in its Spanish initials).This study took into account the habitats of peninsular Spain, which occupies an area of some 500,000 km2. In this territory, the areas deemed to provide natural habitats are defined by Directive 92/43/EEC. The impact of new infrastructures on connectivity was assessed by comparing two scenarios, with and without the plan, for the major new road and railway networks. The calculation of the connectivity index (CI) requires the use of a raster methodology based on the Arc/Info geographical information system (GIS). The actual calculation was performed using a program written in Arc/Info Macro Language (AML); this program is available in FragtULs (Mancebo Quintana, 2007), a set of tools for calculating indicators of fragmentation caused by transport infrastructure (http://topografia.montes.upm.es/fragtuls.html).The indicator of connectivity proposed allows the estimation of the connectivity between all the patches of a territory, with no artificial (non-ecologically based) boundaries imposed. The model proposed appears to be a useful tool for the analysis of fragmentation caused by plans for large territories.  相似文献   

14.
The study addresses the potential of using concentrated solar power plants (CSPs) as a sustainable alternative of clean energy generation in the Mediterranean region and, in particular, in its North Africa shore. This location presents attractive conditions for the installation of CSPs, in particular high solar irradiation, good manpower concentration, and proximity and availability of water resources for condenser cooling. Energetic, exergetic, and economic analyses were conducted taking into consideration a particular type of CSPs - the parabolic trough concentrated solar power plant, which incorporates the most proven technology and it is already used in Southern Europe (Spain). In addition, the study considered the impact of project financing and incentives on the cost of energy. The combination of higher values for performance and potentially lower levelized cost of electricity (LCE) for the North Africa Mediterranean Rim than the South of Spain region can yield a very favorable return for the invested capital. Tripoli compared to Almeria presented superior performance and potentially lower LCE values ($0.18/kWh versus $0.22/kWh). This is significant, even when it is taken into consideration the fact that the plant in Tripoli, despite a relatively modest capacity factor of 34%, has a large gross power output of 173,886 MWhe. In addition, the implementation at the Tripoli location of a plant similar to the Anadsol plant has a slight advantage (2–3%) in terms of overall efficiency.  相似文献   

15.
According to the European regulation regarding waste management (which is reflected in the increasing pressure on municipal waste separation and recycling) the choice of suitable political instruments seems to be crucial. Based on scientific research, the variable charges are considered as an effective choice for the regulation. Unfortunately, scientific research is not followed by a local decision making process within the Czech Republic. One of the reasons discussed in this paper is the economy of variable charges and their influence on administrative costs and total costs of the municipal waste management system. There is no doubt that the effectiveness of variable charges is higher than by fixed fees, but the crucial question for local representatives is not the effectiveness but the economy of charges in the waste management.  相似文献   

16.
The paper presents a multivariate measure useful for integrated environmental assessments. It is a weighted distance measure applied to metric data but based on nonparametric statistical procedures. The proposed measure allows all environmental indicators to be used directly without any reduction in dimension (e.g. as in principal component analysis) nor losing variance while being able to tolerate possible non-normality of the indicators, as well as non-linear relationships among them. Results of the hypothetical example and the Mid-Atlantic case study show that the proposed measure is suitable and valuable for integrating multiple indicators into a single index, an important task in integrated environmental assessment.  相似文献   

17.
Goal of the work is to present a simplified methodology to optimize an integrated solid waste management system. The methodology performs two optimizations, namely: (i) minimization of the total cost of the MSW system and (ii) minimization of the equivalent carbon dioxide emissions (CO2e) generated by the whole system. The methodology is modeled via non-linear mathematical equations, uses 32 decision variables and does not require complex LCA databases. The proposed model optimally allocates eight MSW components (paper, cardboard, plastics, metals, glass, food wastes, yard wastes and other wastes) to four MSW management technologies (incineration, composting, anaerobic digestion, and landfilling) after source separation of recyclables has taken place. The Region of East-Macedonia and Thrace in Greece was selected as a case study. Results showed that there is a trade off between cost and CO2e emissions. Incineration and composting were favored as the principal treatment technologies, while landfilling was always the least desirable management technology under both objective functions. The recycling participation rate significantly affected all optimum scenarios.  相似文献   

18.
ABSTRACT

Cities, with their increasing populations, are host to a range of issues including non-climatic factors due to the prevailing development paradigm, discriminatory urbanisation patterns, and weak governance structures. Climate change poses an additional challenge and exacerbates existing vulnerabilities affecting cities and its people, especially the urban poor. This paper highlights the barriers and enablers to climate change-related adaptation experienced in some of Bengaluru’s informal settlements. The barriers described in the paper include economic, social, governance and information related issues that impede local actions and increase vulnerabilities. Enabling factors such as improving social and human capital, gaining formal recognition and most importantly support from agencies (e.g. local government, civil societies, and community leaders), help overcome some of the barriers or challenges. Hence, local level adaptation measures mainstreamed with local developmental agendas help address some of the structural causes of vulnerability. Contextual policies and interventions can facilitate successful local level adaptation measures.  相似文献   

19.
The aim of this work is (1) to discuss approaches and tools to set management goals using operational indicators for coastal management (i.e., indicators that are easy to measure, understand and predict) and validated predictive models and (2) to discuss remedial strategies for sustainable coastal management regarding water quality and the abundance of fish, waterfowl and large aquatic plants. These approaches are exemplified using data from Ringkøbing Fjord, Denmark, which has undergone two major regime shifts during the last decades. This work discusses the changes taken place during the period from 1980 to 2004 (when there are good empirical data). For Ringkøbing Fjord, which is a very shallow, well-oxygenated lagoon dominated by resuspension processes, we have targeted on the following operational indicators, which are meant to reflect seasonal median values for the entire defined coastal area (the ecosystem scale) and not conditions at individual sites or data from shorter time periods: Secchi depth (as a standard measure of water clarity) and chlorophyll-a concentrations (as a key measure of algal biomass). The operational indicators are regulated by a set of standard abiotic factors, such as salinity, suspended particulate matter (SPM), nutrient concentrations (N and P), coastal morphometry and water exchange. Such relationships are quantified using well-tested, general quantitative models, which illustrate how these indicators are interrelated and how they reflect fundamental aspects of coastal ecosystems. We demonstrate that the regime shift in the lagoon can be modelled and quantitatively explained and is related to changes in salinity and nutrient inflow. A very important threshold is linked to increased salinities in the lagoon. For example, when the mean annual salinity is higher than about 9.5‰, large numbers of saltwater species of clams can survive and influence the structure and function of the ecosystem in profound ways. The model also illustrates the dynamic response to changes in nutrient loading. We have presented several management strategies with the goal of keeping the Secchi depth at 2 m, which would stimulate the growth of higher aquatic plants, which are fundamental for fish production and bird abundance in the lagoon. Given the fact that the Secchi depth depends on many variable factors (temperature, TP-inflow from land, salinity, changes in biomasses of macrophytes and clams, which are accounted for in these simulations), our results indicate that in practice it will likely be very difficult to reach that goal. However, it would be realistic to maintain a Secchi depth of 1.5 m if the variability in salinity is minimized and the mean salinity is kept at about 10.2‰.  相似文献   

20.
The objective of this paper is to empirically investigate a two-way statistical relationship between the agriculture environment and rural poverty. To recognise the relationship between the two variables, a time series, co-integration and Granger causality tests have been employed. Secondary data pertaining to Pakistan from 1980–2009 on rural poverty and environmental factors (such as commercial energy consumption, water availability and total cropped area) have been used for the analysis. The empirical results only moderately support the conventional view that rural poverty has a significant long-term casual effect on environmental proxies in Pakistan. The present study finds evidence of uni-directional causality between poverty and the environment in the context of the agriculture sector in Pakistan.  相似文献   

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