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Background Estimations of gaseous mercury volatilization from soils are often complex, stationary and expensive. Our objective was to develop a mobile and more simple, easy to handle and more cost-effective field method allowing rapid estimates of potential Hg emissions from soils. Methods. The study site is located in Germany, about 100 kilometers south-westerly of Berlin and influenced by the river Elbe and its tributary Saale river. The site is representative for a lot of other floodplain locations at the river Elbe and highly polluted with Hg and other heavy metals. For our study we developed a system consisting of a glass chamber gas, two gold traps, a battery operated pump and a gas meter. Adsorbed total gaseous mercury (TGM) in the gold traps was determined by use of atomic absorption spectrometry (AAS). Results and Discussion. In contrast to the common used flux chambers we designed a chamber without inlet and named it gas suck up chamber (GSC). TGM fluxes determined with the GSC showed a very close linear correlation (r = 0.993) between the TGM content in the gold traps and the corresponding pumped gas volume. The TGM adsorbed, increased proportional with increasing gas volume indicating homogenous concentrations of gaseous mercury in the soil air sucked. In contrast to the commonly used dynamic flux chamber with the aim of precisely measuring actual fluxes of Hg from a defined soil area, we focused on developing of a measurement system which will allow rapid estimates of potential Hg emissions of a site. Earlier research at the study site indicated a high potential for releasing volatile Hg from the soil to the atmosphere. Indeed, due to the high Hg content of the soil significant amounts of TGM could be detected and no shortage was reached. Conclusion. Our initial measurements are still too few in number neither to generalize the achieved results nor discuss controlling factors and processes. However, we are pleased to communicate that the developed GSC is well suited to become an effective sampling set up to rapidly estimate the magnitude of Hg volatilization from soils. Outlook. Further measurements at other polluted locations are necessary to verify the GSC method. In addition the use of a mercury analyzer instead of gold traps is planned for faster risk assessments.  相似文献   
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The Arctic is undergoing biological and environmental changes, and a coordinated effort to monitor is critical to detect these changes. The Circumpolar Biodiversity Monitoring Programme (CBMP) of the Arctic Council biodiversity working group, Conservation of Arctic Flora and Fauna (CAFF), has developed pan-Arctic biodiversity monitoring plans that aims to improve the ability to detect and report on long-term changes. Whilst introducing this special issue, this paper also presents the making of the terrestrial monitoring plan and discusses how the plan follows the steps required for an adaptive and ecosystem-based monitoring programme. In this article, we discuss how data on key findings can be used to inform circumpolar and global assessments, including the State of the Arctic Terrestrial Biodiversity Report, which will be the first terrestrial assessment made by the CBMP. Key findings, advice for future monitoring and lessons learned will be used in planning next steps of pan-Arctic coordinated monitoring.  相似文献   
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Tundra-breeding birds face diverse conservation challenges, from accelerated rates of Arctic climate change to threats associated with highly migratory life histories. Here we summarise the status and trends of Arctic terrestrial birds (88 species, 228 subspecies or distinct flyway populations) across guilds/regions, derived from published sources, raw data or, in rare cases, expert opinion. We report long-term trends in vital rates (survival, reproduction) for the handful of species and regions for which these are available. Over half of all circumpolar Arctic wader taxa are declining (51% of 91 taxa with known trends) and almost half of all waterfowl are increasing (49% of 61 taxa); these opposing trends have fostered a shift in community composition in some locations. Declines were least prevalent in the African-Eurasian Flyway (29%), but similarly prevalent in the remaining three global flyways (44–54%). Widespread, and in some cases accelerating, declines underscore the urgent conservation needs faced by many Arctic terrestrial bird species.  相似文献   
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Humans are now virtually found everywhere in the world. They changed the global nitrogen and phosphate cycles, create light pollution and affect the soundscapes, even in remote wilderness areas. The destruction of the earth and its original habitat is found on land, in the ocean and now, in the atmosphere. Of note are the big impacts from the many small contaminations (e.g., Ott in Sound truth and corporate myths: the legacy of the Exxon Valdez oil spill. Dragonfly Sisters Press, Cordova, 2005). The global magnitude of this man-made impact is virtually unprecedented in human history. Indigenous populations lived within earth??s carrying capacity for easily over 10,000?years, and they never caused such global impacts. It is obvious from most metrics that these problems steeply increased during the last 50?years. This suggests that global procedures and policies, and arguably driven by western industrialized countries, cultures and institutions setting the global framework, are affecting sustainability in dramatic ways. Based on documented and public sources, here I show the brief history, European thought, its global expansion, successes and global sustainability failures. There is an inherent and widely acknowledged conflict between growing the gross domestic product (GDP) and biodiversity, and when considering that we all live on one finite world. Works by Daly, Diamond, Flannery, Shtilmark, Leopold and many others make that already widely clear. Our land- and seascapes are currently overcommitted. With an increase of the human population of over 9?billion people in the next 100?years??likely earlier??we are at the very brink of biodiversity and humanity, and of the earth as we know it. Business as usual, and purely technical and industrial environmental efforts will not help us, and instead, we need a sustainability reform of institutions, education, funding schemes, cultures and society if we want to keep striving, or at least maintain the status quo.  相似文献   
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Ambio - This review provides a synopsis of the main findings of individual papers in the special issue Terrestrial Biodiversity in a Rapidly Changing Arctic. The special issue was developed to...  相似文献   
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The measurement error model is a well established statistical method for regression problems in medical sciences, although rarely used in ecological studies. While the situations in which it is appropriate may be less common in ecology, there are instances in which there may be benefits in its use for prediction and estimation of parameters of interest. We have chosen to explore this topic using a conditional independence model in a Bayesian framework using a Gibbs sampler, as this gives a great deal of flexibility, allowing us to analyse a number of different models without losing generality. Using simulations and two examples, we show how the conditional independence model can be used in ecology, and when it is appropriate.  相似文献   
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