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81.
After introducing soft defence techniques as an alternative to hard defence techniques, the need is emphasized to consider the coastal area as an integral system. By recalling the main driving factors for coastal management: conflict resolution, resilience and sustainability, we logically arrive at the concepts of ecological engineering and ecotechnology, which are increasingly acknowledged as possible solutions to achieve sustainable use of coastal space as a resource. In this context, we refer to the principles of self design and of ecosystem conservation. In order to deal with real situations we are in need of fundamental ‘tools’ for the application of the soft intervention technology approach. We therefore introduce the concept of physiographic units and develop an initial elaboration for a coastal stretch and for coastal wetlands. The latter deserve more attention because of the already established practices of ecotechnology, at least as far as water and soil quality are concerned, but certainly also concerning morphology, especially in the future. We conclude by briefly discussing how activities undertaken in two research projects currently being conducted under the framework of the Marine Science and Technology Program of the Commission of the European Communities are expected to contribute to the concepts introduced here.  相似文献   
82.
This article examines the concept of sustainability (sustainable development, sustainable societies) with a view to providing a means of considering the idea in such a way as to be more useful to concerns of policy. A brief background is given, covering the historical development of the concept, the constituent ecological and social concerns that lie behind it, and some aspects of the sustainability debate in Australia. Some attributes of a sustainable future, as evident from the literature, are listed. The value base of the concept is recognized, and the correct place for sustainability concerns is identified within a simple policy-making model. The complexity of such a model in the real world is explored using a list of thecontexts of sustainability, illustrated with examples from Australian natural resource management. Finally, the more dynamic and flexible nature of patterns of production and consumption in more sustainable societies is recognized and explained, as are two guiding directives to be applied in the search for models which display characteristics of sustainability.  相似文献   
83.
Review of sustainability terms and their definitions   总被引:2,自引:0,他引:2  
Terminology in the field of sustainable development is becoming increasingly important because the number of terms continues to increase along with the rapid increase in awareness of the importance of sustainability. Various definitions of terms are used by different authors and organizations, for example, green chemistry, cleaner production, pollution prevention, etc. The importance of this topic has stimulated research into the problems of clarifying ambiguity and classifying terms used in the sustainability field. This paper provides results of the literature survey and summarizes the definitions of the terms, focusing on the environmental engineering field. In some cases, it proposes an improved definition. A hierarchical classification of the terms and their relationships has been based on a layer format that is presented graphically.  相似文献   
84.
Emergy and economic methods were used to evaluate and compare three fish production models, i.e., cage fish farming system, pond intensive fish rearing system and semi-natural extensive pond fish rearing system, in Nansi Lake area in China in the year 2007. The goal of this study was to understand the benefits and driving forces of selected fish production models from ecological and economic points of view. The study considered input structure, production efficiency, environmental impacts, economic viability and sustainability. Results show that the main difference among the three production systems was the emergy cost for fish feed associated with their feeding system, i.e., feeding on natural biomass such as plankton and grass or on commercial feedstock. As indicated by EYR, ELR and ESI, it can be clearly shown that the intensive production model with commercial feed is not a sustainable pattern. However, the point is that more environmentally sound patterns do not seem able to provide a competitive net profit in the short run. The intensive pond fish farming system had a net profit of 2.57E+03 $/ha, much higher than 1.27E+03 $/ha for cage fish farming system and slightly higher than 2.37E+03 $/ha for semi-natural fish farming system. With regard to the drivers of local farmer’s decisions, the accessibility of land for the required use and investment ability determine the farmer’s choice of the production model and the scale of operation, while other factors seem to have little effect. Theoretically, the development of environmentally sustainable production patterns, namely water and land conservation measures, greener feed as well as low waste systems is urgently needed, to keep production activities within the carrying capacity of ecosystems. Coupled emergy and economic analyses can provide better insight into the environmental and economic benefits of fish production systems and help solve the problems encountered during policy making.  相似文献   
85.
Fertility status of soils of three wetland types in Akwa Ibom State, Nigeria, was investigated. The wetland types are Inland Valley (IV), Flood Plain (FP) and Mangrove (MG). The soils have silt-clay ratios above 0.15 and 0.25 indicating that they are of young parent materials with low degree of weathering and possible weatherable minerals for plant nutrition. The pH of the soils was near neutral (>6.4) when wet but extremely acid (>3.5) when dried indicating that the soils are potential acid sulphate soils. Organic matter content was high with mean values of 12.59, 6.03 and 3.20% for IV, FP and MG soils, respectively. Total N (nitrogen) was low except in IV soils where the value was above the 0.30% critical level. The C:N ratios were narrow with mean of 20.90, 12.17 and 12.12 for IV, FP and MG soils, respectively. The contents of basic cations [Calcium (Ca), Magnesium (Mg), Potasium (K) and Sodium (Na)] were low while acidic cations [Aluminium (Al) and Hydrogen (H)] were high. The Ca:Mg ratios were below the optimum range of 3:1 to 4:1 required for most crops. The Mg:K ratios were above 1.2, below which yields of crops like corn and soybean may be reduced. Effective cation exchange capacity (ECEC) was below the 20 cmol/kg. Percent base saturation was low (<38) indicating that the soils are potentially less fertile. Exchangeable Al and percent Al saturation were high, above 60% in IV and FP soils. Electrical conductivity was above the critical value of 2 dsm−1 while exchangeable sodium percentage was less than 15. Available Phosphorus (P) and low, <10 ppm and free Fe2O3/clay ratios were <0.15. Positive correlation existed between silt and ECEC, implying that silt contributed to nutrient status of the soils. Generally, fertility status of the soil is low and would require maintenance of adequate organic matter, application of lime and organic and inorganic fertilizers, drainage and irrigation if the land is to be used for intensive/sustainable crop production. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
86.
There are multiple challenges regarding use and governance of landscapes’ goods, functions and intangible values for ecosystem health and human well-being. One group of challenges is to measure and assess principal sustainability dimensions through performance targets, so stakeholders have transparent information about states and trends. Another group is to develop adaptive governance at multiple levels, and management of larger geographical areas across scales. Addressing these challenges, we present a framework for transdisciplinary research using multiple landscapes as place-based case studies that integrates multiple research disciplines and non-academic actors: (1) identify a suite of landscapes, and for each (2) review landscape history, (3) map stakeholders, use and non-use values, products and land use, (4) analyze institutions, policies and the system of governance, (5) measure ecological, economic, social and cultural sustainability, (6) assess sustainability dimensions and governance, and finally (7) make comparisons and synthesize. Collaboration, communication and dissemination are additional core features. We discuss barriers bridges and bridges for applying this approach.  相似文献   
87.
ABSTRACT

The large share of carbon emitted by energy-intensive industries in the extraction and processing of basic materials must be limited to decarbonise society and the economy. Ways in which the state can govern industrial decarbonisation and contributes to green state theory are explored by addressing a largely ignored issue: the green state’s industrial relations and its role in industrial governance. With insights from a Swedish case study, the tension between the state’s economic imperative and ecological concerns in greening industry are shown to persist. However, as the energy-intensive industry’s previously privileged position in the economy is weakening, industry is opened to decarbonisation strategies. While the case exposes a number of governance challenges, it also suggests potential areas where the state can pursue decarbonisation in energy-intensive industry and points the way to an active role of the green state in governing industrial decarbonisation and greening industry.  相似文献   
88.
This paper captures the lessons learned from the implementation of water supply and sanitation interventions in Mayiwane community in the rural northeastern region of the Kingdom of Swaziland, relating to water system rehabilitation, water quantity and quality improvements, and the promotion of latrine construction. The issues examined include both the dimensions of implementation efficiency and project effectiveness: first identifying the inputs, activities and final outputs and, then, tracking the entire project cycle, from design to implementation and monitoring. To draw meaningful lessons for the sustainability of similar interventions, project evaluation involved extensive fieldwork, water sampling and testing, review of documentation, and interviews with community members and officials of governmental, civil society and collaborating external agencies. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
89.
This essay responds to the keynote address by Cox by discussing the ways in which critical rhetoric is implicated in environmental communication (EC) as a crisis discipline, as well as the ways in which EC, so positioned, is implicated within a broader coherentist epistemology. Issues of exigency, representation, and sustainability are considered, along with an examination of the concepts of nominalism and doxa as they relate to the enterprise of EC research. The critical cultural politics embedded in much EC scholarship are also addressed in terms of their intersections with the increasingly unscrupulous abuse of language within antienvironmental administrative rhetorics.  相似文献   
90.
Solid waste, including municipal waste and its management, is a major challenge for most cities and among the key contributors to climate change. Greenhouse gas emissions can be reduced through recovery and recycling of resources from the municipal solid waste stream. In São Paulo, Brazil, recycling cooperatives play a crucial role in providing recycling services including collection, separation, cleaning, stocking, and sale of recyclable resources. The present research attempts to measure the greenhouse gas emission reductions achieved by the recycling cooperative Cooperpires, as well as highlight its socioeconomic benefits. Methods include participant observation, structured interviews, questionnaire application, and greenhouse gas accounting of recycling using a Clean Development Mechanism methodology. The results show that recycling cooperatives can achieve important energy savings and reductions in greenhouse gas emissions, and suggest there is an opportunity for Cooperpires and other similar recycling groups to participate in the carbon credit market. Based on these findings, the authors created a simple greenhouse gas accounting calculator for recyclers to estimate their emissions reductions.  相似文献   
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