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331.
Williams Paula Alessa Lilian Abatzoglou John T. Kliskey Andrew Witmer Frank Lee Olivia Trammell Jamie Beaujean Grace Venema Rieken 《Regional Environmental Change》2018,18(2):547-559
Regional Environmental Change - Many papers have addressed the differing approaches to observation by scientists collecting instrumented data and by community or local knowledge-based observations.... 相似文献
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Regional Environmental Change - This article presents historic energy profiles in order to understand the changing roles of three critical energy flows in eastern Canadian agroecosystems. The first... 相似文献
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Emily A. Botts Genevieve Pence Stephen Holness Kerry Sink Andrew Skowno Amanda Driver Linda R. Harris Philip Desmet Boyd Escott Mervyn Lötter Jeanne Nel Tammy Smith Fahiema Daniels Samuel Sinclair Warrick Stewart Jeffrey Manuel 《Conservation biology》2019,33(6):1235-1246
Systematic conservation planning is intended to inform spatially explicit decision making. Doing so requires that it be integrated into complex regulatory and governance processes, and there are limited instances where this has been achieved effectively. South Africa is a global leader in the application of conservation plans, the outputs of which are widely used for spatial planning and decision making in many spheres of government. We aimed to determine how conservation planning in the country progressed from theory to implementation, and to identify practical actions that enabled this transition, by assessing temporal trends in the characteristics of conservation plans (1990–2017, n = 94). Since 2010 conservation planning has entered an operational period characterized by government leadership of plans, administrative rather than ecological planning domains, decreasing size of planning units, increasing emphasis on end-user products, and scheduled revision of plans. Key actions that enabled this progression include transitioning leadership of plans from scientists to practitioners, building capacity within implementing agencies, creating opportunities to integrate plans in legislative processes, establishing a strong community of practice, adopting implementation-focused methods, and balancing standardization with innovation. Learning from this model will allow other countries, particularly those with a similar megadiverse, developing context, to operationalize conservation planning into spatial planning and decision making. 相似文献
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Silvestre García de Jalón Silvia Silvestri Andrew P. Barnes 《Regional Environmental Change》2017,17(2):399-410
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
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Assemblages of macroalgae are believe to be among the most productive ecosystems in the world, yet difficulties in obtaining
direct estimates of biomass and primary production have led to few macroalgal data sets from which the consequences of long-term
change can be assessed. We evaluated the validity of using two easily measured population variables (frond density and plant
density) to estimate the more difficult to measure variables of standing crop and net primary production (NPP) in the giant
kelp Macrocystis pyrifera off southern California. Standing crop was much more strongly correlated to frond density than to plant density. Frond density data collected in summer
were particularly useful for estimating annual NPP, explaining nearly 80% of the variation in the NPP from year to year. Data
on frond densities also provided a relatively good estimate of seasonal NPP for the season that the data were collected. In
contrast, estimates of seasonal and annual NPP derived from plant density data were less reliable. These results indicate
that data on frond density collected at the proper time of year can make assessments of NPP by giant kelp more tractable.
They also suggest that other easily measured variables that are strongly correlated with standing crop, such as surface canopy
area, might serve as similarly useful proxies of NPP. 相似文献
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Gavin H. R. Risley Andrew Curtis Elmore Joel G. Burken Grzegorz Galecki 《补救:环境净化治理成本、技术与工艺杂志》2011,21(3):103-119
While the techniques and technologies associated with contaminated sediment remediation are relatively mature, there are several issues associated with these practices that make them unattractive. The inability of currently used mechanical mixing implements to place amendments in aqueous environments and their intrusive behavior toward benthic communities are just two examples of a necessity for an improved delivery method. Waterjets may be a viable option for placement of particulate remediation amendments, such as activated carbon and granular iron, at depth. A custom waterjet nozzle and injection system has been fabricated by the authors to examine this delivery concept. The developed injection system's performance was tested by characterizing the waterjet‐delivered amendment (activated carbon and granular iron) distributions in a surrogate sediment. The delivered amendment distributions followed similar patterns for a range of injection times and a variety of amendments. The injection depths, however, were dependent upon the type of amendment being injected. These findings have led to a better understanding of what occurs during an amendment injection, which can be used for a more controlled placement of remediation amendments using this technique in the future. The laboratory results indicate that the subject waterjet system may have the potential for field‐scale applications, especially for granular iron delivery, as the authors were able to place between 60 and 70 wt percent into a surrogate sediment bed along the path of injection. © 2011 Wiley Periodicals, Inc. 相似文献
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