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91.
Agroforestry is often an economically viable land-use option for the environmental rehabilitation of salinized cropping areas in irrigated drylands, but afforestation initiative at the farm level is subject to various socio-political constraints. We analyzed the factors that affect farmer decisions with respect to the agroforestry adoption using an ex ante approach through Ethnographic Decision Tree Modeling (EDTM). Constraints on agroforestry adoption were identified via a review of legal documents, focus-group discussions, and a farm survey in northwest Uzbekistan. The findings highlighted the importance of farmer perceptions of risk with respect to decision making surrounding the adoption of alternative land uses. The EDTM analysis allowed determining those policy incentives for afforestation that could directly influence the decision-making process of potential participants. In particular, there is a need for increased land-use flexibility, improved land tenure and tree plantation proprietorship security, increased awareness raising and training in agroforestry practices, and greater institutional support.  相似文献   
92.
Population viability analysis (PVA) is widely used to assess population‐level impacts of environmental changes on species. When combined with sensitivity analysis, PVA yields insights into the effects of parameter and model structure uncertainty. This helps researchers prioritize efforts for further data collection so that model improvements are efficient and helps managers prioritize conservation and management actions. Usually, sensitivity is analyzed by varying one input parameter at a time and observing the influence that variation has over model outcomes. This approach does not account for interactions among parameters. Global sensitivity analysis (GSA) overcomes this limitation by varying several model inputs simultaneously. Then, regression techniques allow measuring the importance of input‐parameter uncertainties. In many conservation applications, the goal of demographic modeling is to assess how different scenarios of impact or management cause changes in a population. This is challenging because the uncertainty of input‐parameter values can be confounded with the effect of impacts and management actions. We developed a GSA method that separates model outcome uncertainty resulting from parameter uncertainty from that resulting from projected ecological impacts or simulated management actions, effectively separating the 2 main questions that sensitivity analysis asks. We applied this method to assess the effects of predicted sea‐level rise on Snowy Plover (Charadrius nivosus). A relatively small number of replicate models (approximately 100) resulted in consistent measures of variable importance when not trying to separate the effects of ecological impacts from parameter uncertainty. However, many more replicate models (approximately 500) were required to separate these effects. These differences are important to consider when using demographic models to estimate ecological impacts of management actions.  相似文献   
93.
A procedure is outlined which allows consideration of both objective and subjective indicators to establish priorities in plan implementation of water resource development. The objective procedure utilizes stepwise multiple discriminant analysis to predict community performance regarding planned project implementation, based on previous project implementation in the Northeast. The subjective procedure incorporates prior probabilities developed by the planner, based on observation and experience gained through the planning process. The proposed analysis could eliminate waste through better allocation of planning funds to implementation studies exhibiting higher probability of early implementation.  相似文献   
94.
Due to expansion of the capital area in Finland, industrial areas are being replanned for residential and commercial use. The soil in these areas is sometimes contaminated, and must therefore be cleaned before building. In spring 1997 the City of Helsinki and the National Technology Agency of Finland declared a contract-based competition for cleaning the polluted soil of the planned Toukolanranta residential area. Nine proposals entered the competition, and the problem was to choose three best candidates for test-cleaning a small part of the region considered. The winner of the test-cleaning phase will get the contract for cleaning the whole area. The proposals were evaluated based on five criteria defined by the competition board consisting of eight experts. The finalists were chosen aided by the SMAA-2 Stochastic Multicriteria Acceptability Analysis technique. SMAA-2 is a method for analysing what kind of preferences favour each alternative. This method is particularly useful in applications, where it is difficult or impossible to obtain accurate preference information. In this application SMAA-2 was observed to suit well for choosing a small set of best alternatives with different strengths and weaknesses.  相似文献   
95.
本文采用多目标排队决策法对专家的咨询意见进行了定量处理,从各用地部门的经济、生态和社会效益出发,确定了他们的优先级,并结合土地利用现状对今后的土地利用结构作出了合理的调整规划设想。  相似文献   
96.
Achieving sustainable development is an issue of global concern. Accounting for the gross ecosystem product (GEP) value can specifically quantify the value of ecosystems for people, which is conducive to the formulation of sustainable management decisions. We have improved the GEP framework accounting method for the first time and evaluated the ecosystem service value of 36 cities in three provinces in the northeast (TPN) of China from 2000 to 2019, which provides decision-making references for the sustainable development of TPN. The main accounting results and policy recommendations are as follows: (1) The ecological value of Northeast China is in an upward stage—GEP has increased from 3.1 trillion yuan in 2000 to 4.5 trillion yuan in 2019, with climate regulation and water conservation functions being the main driving factors for GEP. (2) Based on the dual analysis of GEP and gross domestic product (GDP), there is still high room for improvement in most cities in the TPN region. While ensuring the protection of ecosystem services, cities can convert ecological value into economic value through carbon trading, water rights trading, ecological compensation, and other methods based on ecological characteristics, which is conducive to the sustainable development of GDP and GEP in the TPN region in the future. (3) The cold and hot spot analysis of GEP also provides decision-making basis for the planning of future ecosystem service protection areas in the TPN region.  相似文献   
97.
For sustainable wastewater management, it is essential to consider social, environmental, geological and technical features as well as economic feature in the decision-making process. A limitation of many of the earlier works on wastewater management is that they take into account only financial criteria to make a decision for a given problem. Moreover, the decision-makers’ (DMs) attitude to risk, or optimism degree, when faced with uncertainty is not considered. In this paper, we study the application of risk-based multi-attribute decision-making (RB-MADM) methods to achieve sustainable wastewater management. Consideration of uncertainty, value tradeoffs, and different risk attitudes of decision makers are the important features of the developed methodology. A case study on the Iranian city of Niasar is presented to illustrate how this methodology can be applied to select the most preferred alternative for wastewater management among a set of options. The most preferred option is selected with respect to nine attributes under different optimism/pessimism degrees, using six different MADM methods. The results show that the ranking of options is sensitive to the optimism degree of the DMs. The proposed approach may help policy makers to achieve sustainable wastewater management.  相似文献   
98.
本文简要论述了良好的决策机制是公众参与环境决策的基本保障,分析了当前我国公众参与环境决策运行机制存在的不足,并提出了优化其运行机制的一些思路。  相似文献   
99.
Recent attention has focused on resource management initiatives at the watershed scale with emphasis on collaborative, locally driven, and decentralized institutional arrangements. Existing literature on limited selections of well-established watershed-based organizations has provided valuable insights. The current research extends this focus by including a broad survey of watershed organizations from across the United States as a means to estimate a national portrait. Organizational characteristics include year of formation, membership size and composition, budget, guiding principles, and mechanisms of decision-making. These characteristics and the issue concerns of organizations are expected to vary with respect to location. Because this research focuses on organizations that are place based and stakeholder driven, the forces driving them are expected to differ across regions of the country. On this basis of location, we suggest basic elements for a regional assessment of watershed organizations to channel future research and to better approximate the organizational dynamics, issue concerns, and information needs unique to organizations across the country. At the broadest level, the identification of regional patterns or organizational similarities may facilitate the linkage among organizations to coordinate their actions at the much broader river basin or ecosystem scale.  相似文献   
100.
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