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971.
The investigation was carried out in 8-year-old Scots pine (Pinus sylvestris L.) and lodgepole pine (Pinus contorta var. latifolia Engelm.) plantations on post-mining area, Northeast Estonia. The aim of the study was to assess the suitability of lodgepole pine for restoration of degraded lands by comparing the growth, biomass, and nutrient concentration of studied species. The height growth of trees was greater in the Scots pine stand, but the tree aboveground biomass was slightly larger in the lodgepole pine stand. The aboveground biomass allocation to the compartments did not differ significantly between species. The vertical distribution of compartments showed that 43.2% of the Scots pine needles were located in the middle layer of the crown, while 58.5% of the lodgepole pine needles were in the lowest layer of the crown. The largest share of the shoots and stem of both species was allocated to the lowest layer of the crown. For both species, the highest NPK concentrations were found in the?needles and the lowest in the stems. On the basis of the present study results, it can be concluded that the early growth of Scots pine and lodgepole pine on oil shale post-mining landscapes is similar.  相似文献   
972.
Soil nematode communities (taxa composition, trophic structure, ecological indices) in the area of metallurgical factory (Oravské ferozliatinárske závody) in ?iroká, Northern Slovakia were investigated in 2009. The factory belongs to main sources of emissions originated by ferroalloy production in this region. Four sites (meadows) were selected in a downwind direction from the factory: site A was located 0.85 km far from the factory, and the other sites were maintained in approximately 2-km intervals from each other. Chemical analysis of soil samples showed low concentrations of heavy metals (As, Cd, Cr, Cu, Ni, Pb and Zn), with all values being under Slovak limit concentrations of heavy metals in soils. Only the Cd content in the soil sample from site A slightly exceeded the allowable threshold, but it was decreasing with the distance from the factory, similarly as remaining metals except Cr, with slightly increasing trend of concentration. Within 64 identified nematode genera, the Helicotylenchus, Paratylenchus, Pratylenchus, Acrobeloides, Cephalobus and Rhabditis were most common and eudominant. This was clearly reflected on the trophic structure of nematode communities, where plant feeding nematodes and bacteriovorous prevailed. Significant negative correlation (P?相似文献   
973.
Bulking of activated sludge is a world-widely prevalent problem and can lead to loss of bio-oxidation, further deterioration of effluent quality, and even to a complete breakdown of the entire treatment process. Most common reasons of bulking are bacterial community changes, especially excessive growth of filamentous bacteria or excess of biopolymers on surface of non-filamentous microbes. Because of complex nature of the bulking phenomenon, the successful bulking control strategy finding is still a very important need awaiting new options and advices. The repetitive extragenic palindromic PCR (REP-PCR) fingerprinting method has been applied to distinguish bacterial community in non-bulking and bulking activated sludge. The characteristic REP-PCR fingerprinting patterns, using the Ward??s clustering method, have been analyzed to determine homology/similarity relation between particular non-bulking and bulking sludge sampling. The received clustering results were in high concordance with activated sludge typing done based on physicochemical sludge analysis. The choice and application of molecular typing method in sludge analysis will depend upon the needs, skill level, and resources of the laboratory. The proposed REP-PCR method and statistical analysis of fingerprinting patterns seems to be simple, rapid, and effective methods to show differences between population in non-bulking and bulking activated sludge. It is easy to implement, and it may be useful for routinely activated sludge monitoring as well as may be helpful in early detection of bulking process.  相似文献   
974.
975.
Emerging challenges of risk management, environmental protection, and land-use planning requires integration of stakeholder values and expert judgment. The process of decision making in situation of high uncertainty can be assisted through the use of decision support systems (DSSs). Such DSSs are often based on tools for spatial data representation (GIS) and environmental models that are integrated using multi-criteria decision analysis (MCDA). This paper presents DecernsMCDA implementing all major types of multi-criteria methods and tools (AHP, MAUT, Outranking) under the same user interface. In addition to providing ability for testing model uncertainty associated with selection of specific MCDA algorithms, DecernsMCDA implements new algorithms for parameter uncertainty analysis based on probabilistic approaches and fuzzy sets. The paper illustrates application of DecernsMCDA for selecting remedial alternative at radiologically contaminated sites.  相似文献   
976.
As a renewable energy source, the use of forest biomass for electricity generation is advantageous in comparison with fossil fuels; however, the activity of forest biomass power plants causes adverse impacts, affecting particularly neighbouring communities. The main objective of this study is to estimate the effects of the activity of forest biomass power plants on the welfare of two groups of stakeholders, namely local residents and the general population. To this end, we apply two stated preference methods: contingent valuation and discrete choice experiments, respectively. The former method was applied to estimate the minimum compensation residents of neighbouring communities of two forest biomass power plants in Portugal would be willing to accept. The latter method was applied among the general population to estimate their willingness to pay to avoid specific environmental impacts. The results show that the presence of the selected facilities affects individuals’ well-being. On the other hand, in the discrete choice experiments conducted among the general population all impacts considered were valued, in particular odour and fauna and flora impacts. The results of this study stress the importance of performing an equity analysis of the welfare effects on different groups of stakeholders from the installation of forest biomass power plants, as their effects on welfare are location and impact specific. Policy makers should take into account the views of all stakeholders either directly or indirectly involved when deciding crucial issues regarding the sitting of new forest biomass power plants, in order to achieve an efficient and equitable outcome.  相似文献   
977.
Coffee is an important commodity crop in Zimbabwe and many other African countries in terms of its contribution to local and national economies. Coffee production in terms of productivity and quality face severe constraints due to climate change. A study was therefore carried out to understand and quantify the potential impact of climate change on the coffee sector in Zimbabwe using a bioclimatic modelling approach. Current climatically suitable areas were identified and compared with those areas identified to be climatically suitable under projected 2050 climatic conditions. The projected climatic conditions were obtained from climate predictions of two models: CCSM4 model and HadGEM2 model. Coffee production was found to be mostly sensitive to precipitation factors as these were the most important in determining climatic suitability of coffee production in Zimbabwe. The modelling showed that current coffee suitability varies spatially between the four coffee producing districts in Zimbabwe. Chipinge district has the largest area climatically suitable for coffee production followed by Chimanimani district with Mutare district having the smallest. The modelling predicted that there will be a spatial and quantitative change in climatic suitability for coffee production in Zimbabwe by 2050. The greatest changes are projected for Mutare district where over three quarters according to the CCSM4 model and the entire district according to the HadGEM2 model will turn marginal for coffee production. A westward shift in climatic suitability of coffee was observed for Chipinge and Chimanimani district. The models predicted a loss of between 30,000 ha (CCSM4) and 50,000 ha (HadGEM2) in areas climatically suitable for coffee production by 2050 in Zimbabwe. These changes are likely to be driven by changes in the distribution of precipitation received in the coffee areas. The study presents possible adaptation measures that can be adopted by the coffee sector in Zimbabwe and the region to maintain coffee productivity under a changing climate.  相似文献   
978.
Legitimacy of urban climate change adaptation: a case in Helsinki   总被引:1,自引:0,他引:1  
While there is general agreement on the necessity for local adaptation, there is a wide range of different understandings of what type of adaptation is seen as legitimate. It is often contested who should actively steer and take part in local adaptation, for which reasons and based on what kind of mandate, and with which methods. Planning theory can serve as a helpful reference point for examining the sources of legitimacy for adaptation in an urban context. From a planning perspective, adaptation is concerned with climate change as one out of many issues planning has to respond to. The layered co-existence of planning paradigms in practice suggests diverse, sometimes contradictory sources of legitimacy for urban planning and—as we claim here—also for climate change adaptation. This study examines the legitimacy of adaptation from a planning theoretical perspective in Helsinki, drawing on semi-structured interviews and social network analysis to show how adaptation is commonly understood from a rationalist perspective as an apolitical activity with local authorities’ experts designing and implementing adaptation. Nevertheless, some of the central actors understand adaptation as a communicative activity and a common deliberation of solutions. The co-occurrence of disparate paradigms results in ambiguous legitimacy that can impede the successful implementation of local climate change adaptation.  相似文献   
979.
The purpose of this study was to investigate the climate change impacts, vulnerability and adaptive capacity of the electrical energy sector in Cyprus. Spatial vulnerability of the island was assessed using the degree-day indicator to investigate heating and cooling demands in the near future using daily temperature projections from regional climate models (RCMs). Using daily electrical energy consumption data for the present climate, an impact model linking consumption and temperature was constructed and this relationship was projected to the future climate using the data from the RCMs and assuming the same technology use. Our impact model results showed that for the period between November and April (‘cold period’), a decreasing trend in electrical energy consumption is evident due to warmer conditions in the near future, while for the period between May and October (‘warm period’), an increasing trend in electricity consumption is evident as warmer conditions dominate by 2050. Regarding the spatial vulnerability assessment, the cooling degree-day indicator testified that major increases in cooling demand, between 100 and 200 degree-days, are expected in inland and southern regions during the summer in the near future. In addition, increases of about 20–50 degree-days are anticipated during autumn. Conversely, energy demand for heating is projected to decrease during spring and winter, especially in the higher elevation parts of the island. More precisely, reductions of about 30–75 degree-days are projected during spring, while greater reductions of about 60–90 degree-days are expected during winter in heating demand, especially for in the near future. The ability of the energy sector to adapt and follow these changes was deemed to be satisfactory reducing the overall vulnerability of the sector to future climate change.  相似文献   
980.
The objective of this paper is to analyse the impacts of climate change on a pine forest stand in Central Siberia (Zotino) to assess benefits and risks for such forests in the future. We use the regional statistical climate model STARS to develop a set of climate change scenarios assuming a temperature increase by mid-century of 1, 2, 3 and 4 K. The process-based forest growth model 4C is applied to a 200-year-old pine forest to analyse impacts on carbon and water balance as well as the risk of fire under these climate change scenarios. The climate scenarios indicate precipitation increases mainly during winter and decreases during summer with increasing temperature trend. They cause rising forest productivity up to about 20 % in spite of increasing respiration losses. At the same time, the water-use efficiency increases slightly from 2.0 g C l?1 H2O under current climate to 2.1 g C l?1 H2O under 4 K scenario indicating that higher water losses from increasing evapotranspiration do not appear to lead to water limitations for the productivity at this site. The simulated actual evaporation increases by up to 32 %, but the climatic water balance decreases by up to 20 % with increasing temperature trend. In contrast, the risk of fire indicated by the Nesterov index clearly increases. Our analysis confirms increasing productivity of the boreal pine stand but also highlights increasing drought stress and risks from abiotic disturbances which could cancel out productivity gains.  相似文献   
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