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171.
The province of Siena, Italy, enacted a new garbage plan (NGP) with the objective of increasing separate waste collection (SWC), shutting down six landfills and increasing incineration. The aim of the paper is to evaluate costs and benefits of the NGP. The hypothesis is that willingness to pay (WTP) should reflect the value to the community of having better environmental quality, according to the Contingent Valuation literature. The paper reports the results of a contingent valuation (CV). The sample was divided into two subsets: firms and households. Through the information gathered via a detailed questionnaire, parametric and non-parametric estimates were elaborated to analyse the WTP of the population for the benefits flowing from increased SWC, increased incineration and shutting down of landfills. These values were expressed as a share of the tax actually paid. Although a small subset of firms and households valued increasing incineration less positively, requesting compensation, on the whole interviewees (with large differences between firms and households) had a net positive WTP for the provisions included in NGP. Parametric estimation procedures enabled us to analyse the economic as well as social and demographic factors affecting these results. These elements are useful for computing a value for the waste charge that also reflects external effects. Finally, we estimated household income elasticity of WTP for the increase in SWC and found less than one: environmental quality is not a luxury good.  相似文献   
172.
The author examines the reasons behind the current state of the North American metal mining industry. Taking demand-side factors first, he explains the dramatic fall in metals consumption. External shocks are seen to have affected the previously well rationalized structure of supply in the 1960s, bringing about an increase in production costs and limiting capacity for industrial rationalization. At the beginning of the 1980s, the situation is seen to have been exacerbated by a larger number of producers, more supply sources and an increase in costs. During the course of the decade, the author relates how the situation worsened due to the strength of the US dollar and high interest rates.  相似文献   
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A watershed management framework for mountain areas is based on lessons learned from watershed management experience, social and institutional learning, and the use of a watershed management program evaluation in Nepal. The lessons led to the adoption of a subwatershed-based ecosystem approach based on local participation at the subwatershed level. An integrated watershed management framework (IWMF) consisting of eight steps with three checklists was developed focusing on improvement-oriented adaptive management. The eight steps lead to the preparation of a watershed management plan. In the process three checklists are used. While the first checklist has general questions pertaining to watershed analysis, the second allows participation analysis of stakeholders in terms of their strengths, weaknesses, opportunities and threats and opens up new prospects for further reinforcing or building new user group institutions based on consensus. The final checklist consists of hierarchical watershed management objectives, including goals, results and activities leading to a program planning matrix. The framework was applied to watershed planning in the Chure Region to compare the framework-based planning with conventional planning procedures. A significant difference in quality and substance of the output, with and without the use of the framework, suggests that an integrated framework is a useful tool for an ecosystem-based approach to natural resource management and socio-technical conservation.  相似文献   
177.
A fundamental purpose of intergovernmental growth management has been to infuse regional concerns—especially regional environmental and economic development concerns—into local land use planning. This paper presents results from a study of state-mandated local planning in coastal North Carolina during the mid-1990s, addressing in particular local efforts to ‘strike a balance’ between environment and economy as required by the state's planning mandate. While acknowledging the need for coastal resource protection, coastal localities were not striking a balance between environment and economy through their planning efforts beyond stating support for the State's minimum resource protection rules. Within this context, key factors yielding less environmentally focused local planning included both local elected officials' concerns about the need for economic development for jobs and their belief that environmental protection was not a local problem. Factors that tended to shift local planning back toward environmental protection included local officials' perception that the local economy was in good shape and heightened citizen engagement.  相似文献   
178.
The paper explores the relations of (1) regionalized climate change impulses; (2) their impacts on regional industry sectors; and (3) a regional econometric impact analysis. It develops a methodology by which the impulses of a regional climate change scenario can be transformed into ‘primary’ impacts on the capital stock and value added of climate-sensitive regional industries. These industries are vulnerable to ‘creeping’, i.e. continuous, climate change impulses, and they tend to react through ‘defensive’ investment. In addition, a singular flooding event is simulated for a specific local area and its different capital stocks. The stock damages and value-added losses of both the continuous industrial impacts and the singular flooding are inserted into a regional econometric model. This is sectorally disaggregated in stock, value-added and investment functions. It is also calibrated in the very-long run (through to the year 2040), according to different scenarios. The regional economic ‘secondary’ effects on the regional GNP are calculated. In addition to the calculation of regional economic primary and secondary impacts, the methodological issue of generating more transparency of the causal chains by use of damage functions, reaction functions, and comparative defensive strategies are discussed.  相似文献   
179.
Green composites obtained from biodegradable renewable resources have gained much attention due to environmental problems resulting from conventionally synthetic plastics and a global increasing demand for alternatives to fossil resources. In this work we used different cellulose fibers from used office paper and newspaper as reinforcement for thermoplastic starch (TPS) in order to improve their poor mechanical, thermal and water resistance properties. These composites were prepared by using tapioca starch plasticized by glycerol (30 % wt/wt of glycerol to starch) as matrix reinforced by the extracted cellulose fibers with the contents ranging from 0 to 8 % (wt/wt of fibers to matrix). Properties of composites were determined by mechanical tensile tests, differential scanning calorimetry, thermogravimetric analysis, water absorption measurements, scanning electron microscopy, and soil burial tests. The results showed that the introduction of either office paper or newspaper cellulose fibers caused the improvement of tensile strength and elastic modulus, thermal stability, and water resistance for composites when compared to the non-reinforced TPS. Scanning electron microscopy showed a good adhesion between matrix and fibers. Moreover, the composites biological degraded completely after 8 weeks but required a longer time compared to the non-reinforced TPS. The results indicated that these green composites could be utilized as commodity plastics being strong, inexpensive, plentiful and recyclable.  相似文献   
180.
Recent concerns about potential climate-change effects on coastal systems require the application of vulnerability assessment tools in order to define suitable adaptation strategies and improve coastal zone management effectiveness. In fact, while various research efforts were devoted to evaluate coastal vulnerability to climate change on a national to global level, fewer applications were carried out so far to develop more comprehensive and site-specific vulnerability assessments suitable to plan possible adaptation measures at the regional scale. In this respect, specific indicators are needed to address climate-change-related issues for coastal zones and to identify vulnerable areas at the regional level. Two sets of coastal vulnerability indicators were selected, one for regional and one for global studies, respectively, concerning the same features of coastal systems, including topography and slope, geomorphological characteristics, presence and distribution of wetlands and vegetation cover, density of coastal population and number of coastal inhabitants. The proposed set of indicators for the regional scale was chosen taking into account the availability of environmental and territorial data for the whole coastal area of the Veneto region and was based on site-specific datasets characterized by a spatial resolution appropriate for a regional analysis. Moreover, a GIS-based segmentation procedure was applied to divide the coastline into linear segments, homogeneous in terms of vulnerability to climate change and sea-level rise at the regional scale. This approach allowed to divide the Veneto shoreline into 140 segments with an average length of about 1 km, while the global scale approach identified four coastal segments with an average length of about 66 km. The performed comparison indicated how the more detailed approach adopted at the regional scale is essential to understand and manage the complexities of the specific study area. In fact, the 25-m DEM employed at the regional scale provided a more accurate differentiation of the coastal area's elevation and thus of coastal susceptibility to the inundation risks, compared to the 1-km DEM used at the global level. Moreover, at the regional level the use of a 1:20,000 geomorphological map allowed to differentiate the unique landform class detected at the global level (e.g., fluvial plain) in a variety of more detailed coastal typologies (e.g., open coast eroding sandy shores backed by bedrock) characterized by a different sensitivity to climate change and sea-level rise. Accordingly, the information provided by regional indicators can support decision-makers in improving the management of coastal resources by considering the potential impacts of climate change and in the definition of appropriate actions to reduce inundation risks, to avoid the potential loss of valuable wetlands and vegetation and to plan the nourishment of sandy beaches subject to erosion processes.  相似文献   
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