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1.
ABSTRACT: Two case studies highlighting the institutional arrangements and decision-making processes used to attempt to allocate water on large scale river systems in two countries are presented. In both cases the implementation of river plans has been blocked by conflicts between those who wish to use water for irrigation, hydropower, or municipal purposes and those who wish to maintain instream flows for fish and wildlife. To date conflict has blocked the implementation of a large hydropower scheme on the Danube River, downstream from Vienna, Austria, and the construction of municipal and agricultural projects, as well as the relicensing of an existing hydropower facility on the Platte River in Nebraska. Analysis of the decision-making processes and institutional settings of both cases led to the identification of problem areas and development of recommendations that would support the achievement of compromise solutions for management.  相似文献   

2.
In mountain braided rivers, extreme flow variability, floods and high flow pulses are fundamental elements of natural flow regimes and drivers of floodplain processes, understanding of which is essential for management and restoration. This study evaluated flow dynamics and invasive vegetation characteristics and changes in the Ahuriri River, a free-flowing braided, gravel-bed river in the Southern Alps of New Zealand’s South Island. Sixty-seven flow metrics based on indicators of hydrologic alteration and environmental flow components (extreme low flows, low flows, high flow pulses, small floods and large floods) were analyzed using a 48-year flow record. Changes in the areal cover of floodplain and invasive vegetation classes and patch characteristics over 20 years (1991–2011) were quantified using five sets of aerial photographs, and the correlation between flow metrics and cover changes were evaluated. The river exhibits considerable hydrologic variability characteristic of mountain braided rivers, with large variation in floods and other flow regime metrics. The flow regime, including flood and high flow pulses, has variable effects on floodplain invasive vegetation, and creates dynamic patch mosaics that demonstrate the concepts of a shifting mosaic steady state and biogeomorphic succession. As much as 25 % of the vegetation cover was removed by the largest flood on record (570 m3/s, ~50-year return period), with preferential removal of lupin and less removal of willow. However, most of the vegetation regenerated and spread relatively quickly after floods. Some flow metrics analyzed were highly correlated with vegetation cover, and key metrics included the peak magnitude of the largest flood, flood frequency, and time since the last flood in the interval between photos. These metrics provided a simple multiple regression model of invasive vegetation cover in the aerial photos evaluated. Our analysis of relationships among flow regimes and invasive vegetation cover has implications for braided rivers impacted by hydroelectric power production, where increases in invasive vegetation cover are typically greater than in unimpacted rivers.  相似文献   

3.
Alterations to flow regimes for water management objectives have degraded river ecosystems worldwide. These alterations are particularly profound in Mediterranean climate regions such as California with strong climatic variability and riverine species highly adapted to the resulting flooding and drought disturbances. However, defining environmental flow targets for Mediterranean rivers is complicated by extreme hydrologic variability and often intensive water management legacies. Improved understanding of the diversity of natural streamflow patterns and their spatial arrangement across Mediterranean regions is needed to support the future development of effective flow targets at appropriate scales for management applications with minimal resource and data requirements. Our study addresses this need through the development of a spatially explicit reach‐scale hydrologic classification for California. Dominant hydrologic regimes and their physio‐climatic controls are revealed, using available unimpaired and naturalized streamflow time‐series and generally publicly available geospatial datasets. This methodology identifies eight natural flow classes representing distinct flow sources, hydrologic characteristics, and catchment controls over rainfall‐runoff response. The study provides a broad‐scale hydrologic framework upon which flow‐ecology relationships could subsequently be established towards reach‐scale environmental flows applications in a complex, highly altered Mediterranean region.  相似文献   

4.
The provision of leisure facilities is usually assessed on their value to users. This paper outlines the use of contingent valuation methods in an ex ante appraisal of the costs and benefits of enhancing river flow for recreational purposes in a low flow river. A number of rivers in England and Wales experience low flows, especially during summer months, due to over abstraction of water, creating a trade-off between leisure uses and the demands of water consumers. The sequential benefits of enhanced flows are estimated from those associated with abstraction up to licensed limits: to river flow at 70% of licensed abstraction levels; to flow levels required for an environmentally acceptable flow regime, which would permit leisure activities such as fishing, enhanced scenic walking and wildlife encounters. These benefits are compared to the costs which would be incurred to achieve these enhanced flow regimes. The study illustrates the importance of including non-user benefits in benefit-cost analysis, if leisure provision is to be provided in certain areas.  相似文献   

5.
Local governments in Australia, especially in large urban areas, have faced a challenge of the growing quantity of waste generated and the diminishing space for waste disposal in recent years. The central government has demonstrated the importance of developing strategies to make full environmental costs and impacts of waste disposal and material recovery accountable for waste management decision-making. However, research into this field is limited. This paper investigates environmental accounting practices in local government waste management. From a survey conducted with local government authorities in New South Wales (NSW) Australia, it is found that overall the level of direct waste flow and activity accounting is higher than the level of hidden and external environmental cost accounting, though local governments tend to identify and use more physical information associated with waste flows and activities than relevant monetary information. External environmental impacts of waste disposal are often overlooked and show the lowest level of practices. The survey results also indicate that urban local governments have taken more environmental information into account than rural local governments, but such difference is not significant between local governments of different sizes. The complexity of waste technical services and operations is confirmed to have a positive and significant effect on the level of environmental accounting for waste management across local governments surveyed.  相似文献   

6.
Encroachment of riparian vegetation into regulated river channels exerts control over fluvial processes, channel morphology, and aquatic ecology. Reducing encroachment of terrestrial vegetation is an oft-cited objective of environmental flow recommendations, but there has been no systematic assessment of the evidence for and against the widely-accepted cause-and-effect mechanisms involved. We systematically reviewed the literature to test whether environmental flows can reduce the encroachment of terrestrial vegetation into river channels. We quantified the level of support for five explicit cause-effect hypotheses drawn from a conceptual model of the effects of flow on vegetation. We found that greater inundation, variously expressed as changes in the area, depth, duration, frequency, seasonality, and volume of surface water, generally reduces riparian vegetation abundance in channels, but most studies did not investigate the specific mechanisms causing these changes. Those that did show that increased inundation results in increased mortality, but also increased germination. The evidence was insufficient to determine whether increased inundation decreases reproduction. Our results contribute to hydro-ecological understanding by using the published literature to test for general cause-effect relationships between flow regime and terrestrial vegetation encroachment. Reviews of this nature provide robust support for flow management, and are more defensible than expert judgement-based approaches. Overall, we predict that restoration of more natural flow regimes will reduce encroachment of terrestrial vegetation into regulated river channels, partly through increased mortality. Conversely, infrequent deliveries of environmental flows may actually increase germination and subsequent encroachment.  相似文献   

7.
8.
River managers are aware that river restoration entails addressing and effectively solving wicked social-ecological problems. Contemporary river corridor management is characterized by a variety of actors with different perspectives and interests, and by complex institutional settings and legal landscapes. Additionally, at the intersection between litho-, hydro-, and biological fields, new research suggests that river restoration should reactivate matter and energy fluxes, re-establish spatial connections with the floodplains, and enhance aquatic and terrestrial habitats without exacerbating flood risk. First, we outline a general structure of participatory river corridor management that addresses the following key requirements: (1) unambiguous, participatory spatial delineation of the river corridor; (2) comprehensive assessment of the river corridor's hydro-geomorphological, ecological, socio-economic and cultural processes; (3) transparency and consistency of the decision-making process; as well as (4) a coherent envisioning process. Subsequently, we present an overview of two river corridor management processes, conducted in South Tyrol, Italy. Specifically, we analysed the Etsch/Adige River corridor between Laas/Lasa and Glurns/Glorenza in the Upper Vinschgau/Venosta valley characterized by intense agricultural land use and the densely populated Eisack/Isarco River corridor in Brixen/Bressanone. Based on structured interviews with project managers, we highlight strengths and shortcomings of the proposed participatory management and envisage procedural improvements.  相似文献   

9.
Many common pool resources have traditionally been managed through intricate local governance arrangements. Over time, such arrangements are confronted with manifold political, social, economic and ecological changes. However, the ways in which local governance arrangements react to such changes are poorly understood. Using the theoretical concept of institutional adaptation, we analyse the history of Harenna forest, Ethiopia, to examine processes of institutional change over the last 150 years. We find that the traditional institutions that governed Harenna’s resources persisted, in essence, over time. However, these institutions were modified repeatedly to address changes caused by varying formal, supra-regional governance regimes, the development of markets for forest products, increasing population pressure and changes in formal property rights. A key mechanism for adaptation was combining elements from both informal and formal institutions, which allowed traditional rules to persist in the guise of more formal arrangements. Our findings also highlight several constraints of institutional adaptation. For example, by abolishing fora for collective decision-making, regime changes limited adaptive capacity. To conclude, we argue that such insights into traditional resource governance and its adaptability and dynamics over time are essential to develop sustainable approaches to participatory forest management for the future, both in Harenna and more generally.  相似文献   

10.
This paper examines changes in the provision of water services, and in particular drinking water supply, in two Member States of the European Union, Britain England and Wales and France, by considering the impact of the twin processes of water service privatization and the Europeanization of environmental regulatory regimes. The paper demonstrates that in two nations with very different water service traditions, the articulation of these processes has led to profound shifts not only in management style but also in the perception of drinking water supply as a service to consumers. The British and French models are compared as are their responses to these twin processes. It is argued that while the British model has proved more responsive to the exigencies of European Union environmentalstandards,this has been at the expense of public confidence. In France, the existence of a well established traditional management style is, potentially, under greater long term threat from the growth of private water companies and the increasing importance of European legislation.  相似文献   

11.
Managing Protected Areas (PAs) is a challenging task, and globally many instruments have been utilised for this purpose. Existing research demonstrates that the effectiveness of these instruments is highly dependent on their social acceptability among local communities resident within PAs. Consequently, investigating local attitudes and perceptions of Protected Area (PA) policies has been emphasised in recent studies. Drawing on empirical work conducted in two National Parks including river delta ecosystems designated as Ramsar wetlands in northern Greece, this paper examines local residents' perceptions of three hypothesized policy options (regulatory, market-based and participatory) for Park management. The influence of social capital elements (social trust, institutional trust and social networks) on residents' perceptions is explored. The findings reveal a high degree of importance attached by resident communities to Park designation in both PAs, though residents' perceptions of the proposed management options varied. The regulatory option was regarded as the least restrictive, while the most restrictive was perceived to be the market-based option. However, greater benefits were identified by residents from the market-based option, while the fewest benefits were considered to arise from the proposed regulatory option. Furthermore, local residents' perceptions were significantly shaped by the proposed management and decision-making structure offered under each policy option. The influence of different social capital elements on residents' perceptions also varied in the study sample, with social trust and institutional trust positively correlated with the benefits that were perceived to arise from the different policy options. Moreover, when social capital was measured as an aggregate indicator at the level of the individual, it was positively correlated with perceived environmental benefits.  相似文献   

12.
This paper details a case study of economic and natural system responses to alternative water management policies in the Cache La Poudre River basin, Colorado, 1980–1994. The case study is presented to highlight the value and application of a conceptual integration of economic, salmonid population, physical habitat, and water allocation models. Five alternative regimes, all intended to increase low winter flows, were investigated. Habitat enhancements created by alternative regimes were translated to population responses and economic benefits. Analysis concluded that instream flows cannot compete on the northern Colorado water rental market; cooperative agreements offer an economically feasible way to enhance instream flows; and establishing an instream flow program on the Cache La Poudre River mainstem is a potentially profitable opportunity. The alliance of models is a dynamic multidisciplinary tool for use in professional settings and offers valuable insight for decision-making processes involved in water management.  相似文献   

13.
This paper presents a framework for understanding and improving public sector environmental decision making. Within the framework, four interrelated components are discussed: (1) the environmental and cultural context-understanding this context includes understanding what people consider to be environmental problems, the goals and values that they bring to environmental problems and decision processes, specialized and common knowledge about environmental problems, and the institutional settings within which problems are addressed; (2) planning and appraisal activitiesthese activities include forecasting and monitoring exercises, evaluations of past decisions, and decisions that processes ought to be launched to solve specific environmental problems; (3) decision-making modes-these include six typical ways of conducting an environmental problem-solving process, modes which, in the framework, are called emergency action, routine procedures, analysis-centred, elite corps, conflict management and collaborative learning; (4) decision actions-these include five generic steps that are undertaken, formally or intuitively, in virtually any decision-making situation: issue familiarization; criteria setting; option construction; option assessment; and reaching a decision. In the course of describing the framework, we show a decision-making process can be adapted to incorporate sustainability concerns, including fostering sustainable environmental and social systems, meeting obligations to future generations, and searching for robust and reasonable (rather than rigidly optimal) decisions. The framework also helps to illuminate intriguing questions regarding institutional responsibility, decision process complexity and paradigms for environmental decision making.  相似文献   

14.
This article develops a decision-making framework for environmental management that integrates technical, economic, political and legal, and ethical decision levels. It attempts to show how these decision levels can be ordained, integrated and interconnected and postulates a hierarchic concentric sphere system that proposes an environmental management model for long-term solutions. This model can be used as a check list for environmental management decision-making and also as a guide for environmental conflict resolution where environmental problems necessitate several levels of decision making. It integrates various environmental ethical positions and evaluates political decisions into a comprehensive, broadly applicable multidisciplinary approach. The objective of this decision-making model is to interconnect into a simplified sequence different levels of environmental management processes in order to account for sustainability, efficacy, efficiency and the acceptability of environmental management processes in the long term. This is done by observing when an environmental problem needs to be solved within a certain sphere of solutions and when it requires wider frameworks, how these can be established and how this process proves that solidarity is the widest and most reasonable sphere.  相似文献   

15.

Management of air quality by local government in the United Kingdom (England, Scotland, Wales and Northern Ireland) requires a process of local decision-making, involving collaboration between local politicians, authority officers and interest-groups. Since the establishment of the first National Air Quality Strategy for the UK in 1997, local authority environmental health professionals have undertaken a scientific review and assessment process to identify locations where predicted future pollutant concentrations may exceed national air quality objectives. Air quality management areas (AQMAs) are declared where such exceedences are predicted. Over recent years, significant changes in local authority decision-making structures in England, Scotland and Wales have occurred, resulting in changes to the structure and governance in many local authorities. Results are presented from local authority surveys undertaken to examine the occurrence of any conflicts between the science involved in predicting exceedences and the local political decision-making processes in declaring AQMAs. Data are presented for a sample set of local authorities in Great Britain from which it is concluded that decision-making structures in local government are having a demonstrable impact on the designation of AQMAs.  相似文献   

16.
Management of air quality by local government in the United Kingdom (England, Scotland, Wales and Northern Ireland) requires a process of local decision-making, involving collaboration between local politicians, authority officers and interest-groups. Since the establishment of the first National Air Quality Strategy for the UK in 1997, local authority environmental health professionals have undertaken a scientific review and assessment process to identify locations where predicted future pollutant concentrations may exceed national air quality objectives. Air quality management areas (AQMAs) are declared where such exceedences are predicted. Over recent years, significant changes in local authority decision-making structures in England, Scotland and Wales have occurred, resulting in changes to the structure and governance in many local authorities. Results are presented from local authority surveys undertaken to examine the occurrence of any conflicts between the science involved in predicting exceedences and the local political decision-making processes in declaring AQMAs. Data are presented for a sample set of local authorities in Great Britain from which it is concluded that decision-making structures in local government are having a demonstrable impact on the designation of AQMAs.  相似文献   

17.
The Clutha is the largest river in New Zealand. The last two decades have witnessed major conflicts centered on the utilization of the water resources of the upper Clutha river. These conflicts have by no means been finally resolved. The focus of this article is on institutional arrangements for water resource management on the Clutha, with particular reference to the decision-making processes that have culminated in the building of the high dam. It critically evaluates recent experiences and comments on future prospects for resolving resource use conflicts rationally through planning for multiple utilization in a climate of market led policies of the present government.The study demonstrates the inevitable conflicts that can arise within a public bureaucracy that combines dual responsibilities for policy making and operational functions. Hitherto, central government has been able to manipulate the water resource allocation process to its advantage because of a lack of clear separation between its two roles as a policy maker and developer. The conflicts that have manifested themselves during the last two decades over the Clutha should be seen as part of a wider public debate during the last two decades concerning resource utilization in New Zealand. The Clutha controversy was preceded by comparable concerns over the rising of the level of Lake Manapouri during the 1960s and has been followed by the debate over the think big resource development projects during the 1980s.The election of the fourth Labour government in 1983 has heralded a political and economic policy shift in New Zealand towards minimizing the role of public intervention in resource allocation and major structural reforms in the relative roles of central and regional government in resource management. The significance of these changes pose important implications for the future management of the Clutha.  相似文献   

18.
The Hunter Region in New South Wales, Australia, is undergoing rapid economic development based on its black coal resources. Cumulative impacts of new projects cannot be easily assessed with the traditional environmental impact statement. This article examines air quality impacts, and presents a systems analysis model to assist environmental management. The model consists of an input-output model of the regional economy and an air dispersion model. Results are obtained for sulfur oxides and fluorides.  相似文献   

19.
Partnerships and co-operative environmental management are increasing worldwide as is the call for scientific input in the public process of ecosystem management. In Hawaii, private landowners, non-governmental organizations, and state and federal agencies have formed watershed partnerships to conserve and better manage upland forested watersheds. In this paper, findings of an international workshop convened in Hawaii to explore the strengths of approaches used to assess stakeholder values of environmental resources and foster consensus in the public process of ecosystem management are presented. Authors draw upon field experience in projects throughout Hawaii, Southeast Asia, Africa and the US mainland to derive a set of lessons learned that can be applied to Hawaiian and other watershed partnerships in an effort to promote consensus and sustainable ecosystem management. Interdisciplinary science-based models can serve as effective tools to identify areas of potential consensus in the process of ecosystem management. Effective integration of scientific input in co-operative ecosystem management depends on the role of science, the stakeholders and decision-makers involved, and the common language utilized to compare tradeoffs. Trust is essential to consensus building and the integration of scientific input must be transparent and inclusive of public feedback. Consideration of all relevant stakeholders and the actual benefits and costs of management activities to each stakeholder is essential. Perceptions and intuitive responses of people can be as influential as analytical processes in decision-making and must be addressed. Deliberative, dynamic and iterative decision-making processes all influence the level of stakeholder achievement of consensus. In Hawaii, application of lessons learned can promote more informed and democratic decision processes, quality scientific analysis that is relevant, and legitimacy and public acceptance of ecosystem management.  相似文献   

20.
Core themes of geomorphology include: open systems and connectivity; feedbacks and complexity; spatial differentiation of dominant physical processes within a landscape; and legacy effects of historical human use of resources. Core themes of ecology include: open systems and connectivity; hierarchical, heterogeneous, dynamic, and context-dependent characteristics of ecological patterns and processes; nonlinearity, thresholds, hysteresis, and resilience within ecosystems; and human effects. Core themes of environmental governance include: architecture of institutions and decision-making; agency, or ability of actors to prescribe behavior of people in relation to the environment; adaptiveness of social groups to environmental change; accountability and legitimacy of systems of governance; allocation of and access to resources; and thresholds and feedback loops within environmental policy. Core themes common to these disciplines include connectivity, feedbacks, tipping points or thresholds, and resiliency. Emphasizing these points of disciplinary overlap can facilitate interdisciplinary understanding of complex systems, as well as more effective management of landscapes and ecosystems by highlighting drivers of change within systems. We use a previously published conceptual framework to examine how these core themes can be integrated into interdisciplinary research for human–landscape systems via the example of a river.  相似文献   

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