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841.
Ship breaking or recycling in Bangladesh has been a catalyst for the economy by supporting the steel, shipbuilding, furniture, building construction, machinery and electrical industries since the 1980s. Although it has generated huge employment and provided 80–90% of the total steel consumption in the country, it has faced a host of challenges due to a number of negative environmental and social impacts that hinder the sustainable development of this blooming sector. The objective of this paper is to focus on how ship-breaking activities in Bangladesh affect the adjacent environment and the health and safety of workers, as well as management’s approach to the sustainability of the industry, by conducting a review of the available scientific literature. We found that grave environmental pollution, such as physiochemical properties, heavy metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyl compounds (PCBs), organotins, oil and grease pollution, asbestos and other atmospheric pollutants, and its impact on marine ecosystems, biodiversity, forestry, fisheries and human health are the main obstacles for the development of a sustainable ship-breaking industry. In addition, labour safety and occupational health problems, social unrest and conflicts have resulted from the development of the ship-breaking industry in Bangladesh. Inappropriate management practices and inadequate plans regarding ship-breaking activities and processes are the main reasons for these challenges. Effective management measures to mitigate the adverse environmental impact of the ship-breaking industry and to improve the health and safety of workers have now become an urgent requirement.  相似文献   
842.
北戴河及相邻地区的鸟类种数繁多,约有409种,其中属国家一类保护鸟类的有12种,二类保护鸟类的有49种。分析其原因,一是北戴河位于中国东部候鸟迁徙的停歇地;二是生境复杂多样,环境质量优良。为保护鸟类及其生境,应制定并实施相应的地方法规和经济技术政策,建立并完善自然保护区,开展宣传教育,动员公众参与。  相似文献   
843.
This paper recognises the need for a revision of watershed development policy in India in relation to the planning of development interventions involving agricultural intensification and rainwater harvesting and the need for new approaches to assist the planning process. Building on, and using as an example, the results of biophysical and societal impact studies carried out on two watershed development projects in Karnataka three new management/dissemination tools, are suggested. These are (1) the web-based geographical information systems exploratory, climate land assessment and impact management tool dissemination tool for disseminating to policymakers and non-specialist stakeholders the downstream impacts of watershed interventions, (2) the ‘quadrant’ approach for ensuring that sustainability criteria are met and (3) Bayesian networks to investigate the biophysical and societal impacts of interventions. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue  相似文献   
844.
Several medicinal plants used in Italy were analysed to determine natural and artificial radioactivity in those parts (leaves, fruits, seeds, roots, peduncles, flowers, barks, berries, thallus) used generally as remedies. The radionuclides were determined by alpha (238U, 210Po) and gamma (214Pb-Bi, 210Pb, 40K and 137Cs) spectrometry. 238U ranged between <0.1 and 7.32 Bq kgdry−1; 210Po between <0.1 and 30.3 Bq kgdry−1; 214Pb-214Bi between <0.3 and 16.6 Bq kgdry−1; 210Pb between <3 and 58.3 Bq kgdry−1; 40K between 66.2 and 3582.0 Bq kgdry−1; 137Cs between <0.3 and 10.7 Bq kgdry−1. The percentage of 210Po extraction in infusion and decoction was also determined; the arithmetical mean value of percentage of 210Po extraction resulted 20.7 ± 7.5.  相似文献   
845.
For matrix population models, analyses of how sensitive the population growth rate is to changes in vital rates (i.e. perturbations) are important for studies of life history evolution as well as for management and conservation of threatened species. There are two types of sensitivity analyses corresponding to absolute (sensitivity) or relative (elasticity) changes in the vital rates and both types can be applied to both deterministic and stochastic matrix population models. To date, most empirical studies of elasticity and sensitivity of the stochastic growth rate have examined the response to perturbations in the vital rates in a complete set of possible environments. However, it is often of interest to examine the response to perturbations occurring in only a subset of the possible environments. This has been done for periodic time-varying models elsewhere, but here we describe a recently published method for calculating the environment-specific sensitivity and elasticity of the stochastic growth rate and apply this method to data. These environment-specific perturbation analyses provide a logical way of dividing the sensitivity and elasticity among the environments. They give important insight into the selection regime in different environments and can provide valuable information for making management decisions and management evaluations in stochastic environments.  相似文献   
846.
Karst terrain offers a great range of economic assets, provides unique habitats and valuable ecosystem services. Owing to its particular nature, this environment is highly susceptible to destruction. Any interference is likely to have irreversible impacts and disturb the natural balance of the elements (water, soil, flora and fauna) and processes (e.g. corrosion, CO2 sequestration, speleothem growth) that constitute it. Karst areas must therefore be holistically managed in an appropriate and careful manner. A critical overview of current protection legislation in Slovenia has been prepared, with particular reference to karst areas. The major problem is a lack of harmonised multi-sector policies regulating land use and planning throughout the karst region, the absence of detailed guidelines and insufficient pursuance of karst in all its complexity and vulnerability. A comprehensive management approach for karst areas has been proposed and could subsequently be adopted by other karst-rich countries. Management is based on the enforcement of karst-specific legislation, including provision of detailed management plans and their strict implementation. Common database maintenance, reconciliation between various stakeholders and raising public awareness are additional important parts of the approach.  相似文献   
847.
A growing body of research recommends interaction between managers and stakeholders to improve natural resource management decisions. While formative stakeholder research and summative evaluations of communication efforts have been well-studied, less research has included formative evaluations comparing managers and stakeholders to inform communication efforts. This study applies the communication concept of coorientation to the case of deer management on open-space lands owned by Cornell University and develops an approach to coorientation analysis for use with small decision-making teams. Mail surveys were used to assess the level of agreement and accuracy between decision makers and residents of nearby communities. Decision makers and residents varied in the topics for which they accurately predicted each other's responses; these differences have implications for approaches to communication. This study also illustrates the utility of coorientation research to reveal areas of difference within the decision-making team, as well as with the public.  相似文献   
848.

Backcasting is a planning methodology that is particularly helpful when problems at hand are complex and when present trends are part of the problems. When applied in planning towards sustainability, backcasting can increase the likelihood of handling the ecologically complex issues in a systematic and coordinated way, and also to foresee certain changes, even from a self-beneficial point of view, of the market and increase the chances of a relatively strong economic performance. To that end, backcasting should be performed from a set of non-overlapping principles that are general enough to be helpful in the coordination of different sectors of society and in business, as well as to cover relevant aspects of sustainability. Such principles are helpful when developing reliable non-overlapping indicators for monitoring of the development when coordinating various measures from different sectors of the society or within individual firms with each other, and when handling trade-offs in a relevant way. Furthermore, the transition can benefit from being undertaken in a strategic step-by-step manner, by which such investments search for those that combine two qualities: (i) technical flexibility to serve as platforms for future investments in line with non-overlapping principles of sustainability, and (ii) good possibilities of giving relatively fast return on investment. This framework for planning is developed together with the Natural Step, a non-government organization, and in collaboration with a network of scientists and business. Examples are given from firms applying the framework.  相似文献   
849.
In order to assess the potential risk of pipeline underwater leakage, a self-designed experimental setup is carried out to study the gas release rate and dispersion behavior in different release scenarios. A transparent organic glass tank with dimension of 1 m × 0.5 m × 0.5 m (height × width × length) was placed in a wind tunnel. The release pipeline made by stainless-steel with diameter of 25 mm were used to simulate for variation release depth. The different size and shape of leakage orifices in 1 mm, 3 mm, 5 mm in round and 3.5 × 2 mm, 7 × 1 mm in rectangle were designed for comparison. The medium of methane gas was released from the controllable cylinder. The variation parameters of flow rate and pressure were measured by a flow meter and pressure gauge respectively. A high speed camera was employed to recorded the phenomenology of dispersion characteristics and breakup process for a wide range of orifice size in the time-resolved images. The dynamic plume diameter on water surface was measured by a Vernier caliper placed above the water tank. The considered factors including orifice size, leakage pressure and water depth effect on gas flow rate and dispersion behavior was quantitative investigated. The fitting correlation between the gas flow rate and variation parameters can provide fundamental information for evaluation the hazard consequences of gas release in engineering application.  相似文献   
850.
气候变化对我国水文水资源系统的影响研究   总被引:2,自引:0,他引:2  
旨在介绍气候变化对我国水文水资源系统影响研究的进展、方法、技术及其优缺点,并分析气候变暖对我国水文水资源系统的影响结果,同时提出自己的一些建议。  相似文献   
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