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991.
Livestock systems play an important role in the livelihoods of many rural communities in Sub-Saharan Africa while being responsible for an important share of human-induced greenhouse gas emissions. This study aimed to evaluate the potential for adoption of climate smart agricultural practices in Sub-Saharan livestock systems, related to the improvement in feed, animal husbandry, and grassland management. These practices present productivity and mitigation benefits and in some cases may also contribute to enhance resilience. In this study, we used a data set of 1538 farm households across nine Sub-Saharan countries. A mixed logit model was used to assess the influence on adoption and to estimate the probability of adoption. Our results show that there seems to be stronger influence of physical and financial capitals on adoption than the other capitals. Different types of capitals influence the uptake of different agricultural practices. Yet the probability of adoption would change across countries. The results of this study could help to refine adoption estimates calculated through global or regional modelling approaches and to inform the design of policies to better target investments in order to foster adoption.  相似文献   
992.
Regional Environmental Change - The dry forests of Latin America are among the most dynamic deforestation frontiers in the world and are important carbon and biodiversity reservoirs. Our knowledge...  相似文献   
993.
Detailed observations of natural and anthropogenic disturbance events that impact forest structure and the distribution of carbon are essential to estimate changes in terrestrial carbon pools and the associated emissions and removals of greenhouse gasses. Recent advances in remote sensing approaches have resulted in annual and decadal estimates of land-cover change derived from observations using broad-scale moderate resolution imaging spectroradiometer (MODIS) 250 m–1 km imagery. These land-use change estimates, however, are often not attributed directly to a cause or activity and are not well validated, especially in tropical areas. Knowledge of the type of disturbance that caused the observed land-cover changes is important, however, for the quantification of the associated impacts on ecosystem carbon stocks and fluxes. In this paper, we provide estimates of the amount of forest land-cover change in a Mexican forested region and propose an approach for attributing the cause of the observed changes to the underlying disturbance driver. To do so, we collate geospatial and remote sensing data from a variety of sources to summarize statistics about the major disturbances within the Yucatan Peninsula, an “early action” region for the reduction of emissions from deforestation and degradation, from 2005 to 2010. We combine the datasets to develop rules to estimate the likely disturbances that caused the observed land-cover changes based on their spatially explicit location. Finally, we compare our observed disturbance rates to those detected using classified land-cover data derived from MODIS.  相似文献   
994.
Anthropogenic impacts on biodiversity can lead to biotic homogenization (BH) and biotic differentiation (BD). BH is a process of increasing similarity in community composition (including taxonomic, functional, and phylogenetic components), whereas BD is a process of decreasing similarity over space and time. Here, we conducted a systematic review of BH and BD in plant communities in tropical and subtropical forests to identify trends and knowledge gaps. Our bibliometric search in the Web of Science returned 1989 papers, of which 151 matched our criteria and were included in the analysis. The Neotropical region had the largest number of articles, and Brazil was the most represented country with 92 studies. Regarding the type of change, homogenization was more frequent than differentiation (noted in 69.6% of publications). The taxonomic diversity component was measured more often than functional and phylogenetic diversity components. Most studies (75.6%) assessed homogenization and differentiation based on a single observation in time; as opposed to few studies that monitored plant community over multiple years. Forest fragmentation was cited as the main determinant of homogenization and differentiation processes (57.2% of articles). Our results highlight the importance of evaluating community composition over time and more than taxonomic components (i.e., functional and phylogenetic) to advance understanding of homogenization and differentiation. Both processes were scale dependent and not mutually exclusive. As such, future research should consider differentiation as a potential transition phase to homogenization and that potential differences in both processes may depend on the spatial and temporal scale adopted. Understanding the complexity and causes of homogenization and differentiation is essential for biodiversity conservation in a world increasingly affected by anthropogenic disturbances.  相似文献   
995.
Environmental Science and Pollution Research - Free ferulic acid (FA) is a natural compound with antioxidant properties which mitigates the negative effects of cold stress in sheep; however, its...  相似文献   
996.
Environmental Science and Pollution Research - Highly time-resolved particle number size distributions (PNSDs) were evaluated during 5 years (2013–2017) at four background stations in the...  相似文献   
997.
Environmental Science and Pollution Research - Organochlorine pesticides have generated public concern worldwide because of their toxicity to human health and the environment, even at low...  相似文献   
998.
Environmental Science and Pollution Research - The fate of pharmaceuticals during the treatment of effluents is of major concern since they are not completely degraded and because of their...  相似文献   
999.
Environmental Science and Pollution Research - Air pollution is an important cause of non-communicable diseases globally with particulate matter (PM) as one of the main air pollutants. PM is...  相似文献   
1000.
Habitats vary considerably in the level of invasion (number or proportion of alien plant species they contain), which depends on local habitat properties, propagule pressure, and climate. To determine the invasibility (susceptibility to invasions) of different habitats, it is necessary to factor out the effects of any confounding variables such as propagule pressure and climate on the level of invasion. We used 20 468 vegetation plots from 32 habitats in the Czech Republic to compare the invasibility of different habitats. Using regression trees, the proportion of alien plants, including archaeophytes (prehistoric to medieval invaders) and neophytes (recent invaders), was related to variables representing habitat properties, propagule pressure, and climate. The propagule pressure was expressed as the proportion of surrounding urban and industrial or agricultural land, human population density, distance from a river, and history of human colonization in the region. Urban and industrial land use had a positive effect on the proportion of both archaeophytes and neophytes. Agricultural land use, higher population density, and longer history of human impact positively affected the proportion of archaeophytes. Disturbed human-made habitats with herbaceous vegetation were most invaded by both groups of aliens. Neophytes were also relatively common in disturbed woody vegetation, such as broad-leaved plantations, forest clearings, and riverine scrub. These habitats also had the highest proportion of aliens after removing the effect of propagule pressure and climate, indicating that they are not only the most invaded, but also most invasible. These habitats experience recurrent disturbances and are rich, at least temporarily, in available nutrients, which supports the hypothesis that fluctuating resources are the major cause of habitat invasibility. The least invaded habitats were mires and alpine-subalpine grasslands and scrub. After removing the effect of propagule pressure and climate, some habitats actually invaded at an intermediate level had very low proportions of aliens. This indicates that these habitats (e.g., dry, wet, and saline grasslands, base-rich fens, and broad-leaved deciduous woodlands) are resistant to invasion.  相似文献   
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