首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
This paper looks into the complexity of managing flood risks in the Hawkesbury–Nepean catchment, Australia. Several aspects are explored: (1) the complexities created by the way different agencies are involved in assessing flood risks; (2) different perceptions on acceptable flood risk level; (3) community engagement in defining acceptable flood risk level; (4) views on a holistic flood risk management plan; and (5) challenges of a centralised information system. This study concludes that the complexity of managing a large catchment is exacerbated by the difference in the way professionals perceive the problem. This has led to (1) different standards for acceptable risks; (2) inconsistent attempt to set up a regional-scale flood management plan beyond the jurisdictional boundaries; (3) absence of a regional-scale agency with licence to share and update information; and (d) lack of forums for dialogue with insurance companies to ensure an integrated approach to flood management.  相似文献   

3.
4.
5.
The European Union's Structural Funds are implemented by means of Regional Development Plans (RDP), whose regionally scoped environmental assessment is required. We highlight the deficiencies faced by this approach when subregional areas with high conservation natural values are involved and illustrate it with the case of the RDP of Andalusia region on Doñana National Park area (Spain). Commissioned by the World Wildlife Fund, a Strategic Environmental Assessment (SEA) of the Andalusian RDP was carried out focusing on Doñana and its area of influence. This is a complex space where some of the most environmentally valuable features in the continent coexist with a surrounding intense and multi-sector economic activity, threatening its conservation. In the absence of an established sustainability framework in the Region, a “trickle-down” SEA approach evidenced the need to produce a set of environmental, economic and social guidelines for sustainable management of land, against which the RDP objectives were tested for coherence. An “incremental” SEA approach was also tested, which involved the identification of 79 measures and actions stemming from the RDP provisions and other concurrent planning documents reviewed and the qualitative assessment of their individual and cumulative potential impacts on Doñana environments. In the light of the results, a set of complementary mitigating measures was proposed for inclusion in tiered stages of the planning process. Measures to avoid, reduce, remedy and monitor the major types of impact were proposed, including provisions for public participation. SEA emerges as an instrument for non-governmental organizations (NGOs) to carry out independent assessment of public development initiatives.  相似文献   

6.
The Environmental Impact Assessment (EIA) procedure should predict and identify the major impacts of a project development that may cause specific spatial and temporal effects. Early in the EIA, the scoping stage provides all the relevant information on the impacts of the project alternatives. In particular, potential effects on the territorial network such as habitat connectivity loss and accessibility improvements should be taken into account in the various proposed layout alternatives when evaluating transport infrastructure projects. However, several authors have identified deficiencies in practice. The aim of this article is to provide a methodology for the assessment of these territorial impacts using adequate indicators in the early stages of the EIA procedure.

The proposed method is based on a comparison of a range of alternative layouts for a railway line linking two population centres, using indicators calculated with geographic information systems. The methodology was applied to a case study – the rail link between Huelva (Spain) and Faro (Portugal) – and the high speed rail (HSR) and conventional rail were evaluated in different layouts. The method was effective in spatially identifying significant impacts on accessibility improvements, which occurred closer to the cross border area. The conventional railway alternatives have similar accessibility values to the HSR. The results also reveal that connectivity loss is not limited to the area around the infrastructure, but extends throughout the territory. The results are at variance with the initiative proposed by Spanish and Portuguese transport decision-makers, and raise the possibility of selecting a conventional railway option. An adequate territorial evaluation methodology enables the new action to be correctly assessed, and supplies the information required to propose the most suitable alternative from a socio-economic and environmental standpoint, regardless of whether this proposal was initially included in the transport policy.  相似文献   


7.
Characteristics of air–water two-phase flow pattern in a square-mini-channel were investigated experimentally. One sidewall of the flow channel was made of a permeable porous media. Air was fed into the channel from its inlet, while liquid water was injected uniformly into the channel along the permeable sidewall. Based on the results of visualization, the typical flow patterns encountered in the conventional co-current gas–liquid two-phase flow were not observed in the present work. Flow patterns of this special gas–liquid two-phase flow were catalogued, and the influence of gas flow rate and liquid infiltration rate on flow patterns was also analyzed. The results also indicate that the channel differential pressure on both sides brings obvious fluctuations when the liquid is infiltrated. The frequency of this fluctuation depends not only on the amount of liquid infiltration but also relies on the gas flow rate significantly. However, the amount of liquid infiltration barely affects the fluctuation in the amplitude of the pressure differential.  相似文献   

8.
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   

9.
10.
11.
Winter deicers are a major source of chloride contamination to shallow aquifers in northern latitudes. In the greater Chicago area of northeast Illinois, chloride has been accumulating for decades and in many places now exceeds the United States Environmental Protection Agency secondary standard of 250 mg/L. MODFLOW-NWT and MT3D-USGS were used to simulate the accumulation of chloride with 30 years of data in the shallow aquifer of Will County in northeast Illinois. This aquifer is composed of unconsolidated sediments, largely from glacial deposits, overlying a fractured dolomite bedrock. To calibrate to observed heads and chloride, the model needed refined geologic features, higher chloride concentrations on cells representing commercial or industrial lands, lower chloride concentrations on cells representing roads, and point source areas to speed chloride's emergence in the aquifer. These point sources are locally significant and could represent different anthropogenic or geologic features, such as municipal stormwater infrastructure. Future simulations indicate that chloride is not at steady state in the shallow aquifer and wells are at risk of exceeding the secondary standard if winter deicing applications are not reduced. It may take decades for the full impacts of reduced deicing rates to be observed in wells, owing to the long residence time of water in the aquifer. This transient model calibration was possible because of the 30-year dataset collected by communities and government agencies.  相似文献   

12.
We have investigated why conflicts linked to the distribution of power between governments and actors at the national and local levels concerning environmental management of mountain areas in Norway persist despite political intentions to strengthen local powers. We seek to explain this by analysing changes in policies, institutional frameworks, and regional contexts, and the local perceptions of these changes. Paradoxically, the national government's power has apparently been strengthened by new sectoral regulations and more stringent enforcement of the existing ones, increases in the number and extent of protected areas, and failures to act on intentions to devolve power. An additional factor spurring conflicts is the increased importance of tourism to mountain communities. To become more relevant to policies and development in mountain areas, future studies on multilevel governance must address multilevel politics, entire mountain areas, and the context of their development, rather than focusing on minor projects and protected areas.  相似文献   

13.
Hydroelectric dams represent major investments and major sources of environmental and social impacts. Powerful forces surround the decision-making process on public investments in the various options for the generation and conservation of electricity. Brazil’s proposed Belo Monte Dam (formerly Kararaô) and its upstream counterpart, the Altamira Dam (better known by its former name of Babaquara) are at the center of controversies on the decision-making process for major infrastructure projects in Amazonia. The Belo Monte Dam by itself would have a small reservoir area (440 km2) and large installed capacity (11, 181.3 MW), but the Altamira/Babaquara Dam that would regulate the flow of the Xingu River (thereby increasing power generation at Belo Monte) would flood a vast area (6140 km2). The great impact of dams provides a powerful reason for Brazil to reassess its current policies that allocate large amounts of energy in the country’s national grid to subsidized aluminum smelting for export. The case of Belo Monte and the five additional dams planned upstream (including the Altamira/Babaquara Dam) indicate the need for Brazil to reform its environmental assessment and licensing system to include the impacts of multiple interdependent projects.  相似文献   

14.
This paper applies the Kuhn–Tucker model to estimate recreation demand of parks in Sicily. We estimate a fixed coefficient specification and a random coefficient specification to take into account heterogeneity across visitors. Estimates suggest a diversity of preferences across the population and that parks with higher level of quality attributes are more likely to be visited. We also simulate two sets of hypothetical policy scenarios to evaluate and compare the recreational value of each park and the welfare impacts of changes in a quality attribute.  相似文献   

15.
16.
In the last fifty years, many mountain watersheds in temperate countries have known a progressive change from self-standing agro-silvo-pastoral systems to leisure dominated areas characterized by a concentration of tourist accommodations, leading to a drinking water peak during the winter tourist season, when the water level is lowest in rivers and sources. The concentration of water uses increases the pressure on “aquatic habitats” and competition between uses themselves. Consequently, a new concept was developed following the international conferences in Dublin (International Conference on Water and the Environment – ICWE) and Rio de Janeiro (UN Conference on Environment and Development), both in 1992, and was broadly acknowledged through international and European policies. It is the concept of Integrated Water Resource Management (IWRM). It meets the requirements of different uses of water and aquatic zones whilst preserving the natural functions of such areas and ensuring a satisfactory economic and social development. This paper seeks to evaluate a local water resources management system in order to implement it using IWRM in mountain watersheds. The assessment method is based on the systemic approach to take into account all components influencing a water resources management system at the watershed scale. A geographic information system was built to look into interactions between water resources, land uses, and water uses. This paper deals specifically with a spatial comparison between hydrologically sensitive areas and land uses. The method is applied to a French Alps watershed: the Giffre watershed (a tributary of the Arve in Haute-Savoie). The results emphasize both the needs and the gaps in implementing IWRM in vulnerable mountain regions.  相似文献   

17.
In December 2010, the German government increased the maximum ethanol content that can be blended with petrol from 5% to 10%, which facilitated the introduction of the ethanol–petrol blend E10. The revised ethanol–petrol blend was introduced with ambitions towards decarbonizing the transport sector as well as to support energy security and rural development. While usually supportive of actions aimed to combat climate change, the great majority of German motorists have refused to buy E10. The lacking demand for E10 is the empirical phenomenon addressed by this study. How did the fuel suppliers comply with the policy provisions? Which actors made attempts to influence the motorists’ demand for the new ethanol–petrol blend? Which actor was assigned the responsibility for the problems that occurred upon the rollout of the new fuel type? These research questions guide this study, which concentrates on the behaviour of transport fuel suppliers and consumers in mandated markets, that is, markets created by policy provisions.  相似文献   

18.
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   

19.
When ecosystem services value estimates are applied in the economic assessment of environmental policies, high accuracy of these estimates is required. One of the directions in the scientific discussion on biases in stated preference (SP) valuation surveys builds on dual-process theories of judgment. The paper contributes to this literature by presenting an experiment where two types of judgment were induced via separate versus joint valuation of environmental goods. The results demonstrated that policy relevance of environmental issues, e.g. the need for conservation measures increases emotional response, causing a larger bias in the separate design as it involves ‘valuation by feeling.’ This finding suggests that the context of a specific policy, which is often the reason for conducting SP surveys, influences the answers, thereby making the results less reliable for use in cost–benefit analysis.  相似文献   

20.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号