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The vulnerability of forest ecosystem services to climate change is expected to depend on landscape characteristic and management history, but may also be influenced by the proximity to the southern range limit of constituent tree species. In the Western Rhodopes in South Bulgaria, Norway spruce is an important commercial species, but is approaching its current southern limit. Using climate sensitive forest models, we projected the impact of climate change on timber production, carbon storage, biodiversity and soil retention in two representative landscapes in the Western Rhodopes; a lower elevation landscape (1000–1450 m a.s.l) dominated by mixed species forests, and a higher elevation landscape (1550–2100 m a.s.l.) currently dominated by spruce. In both landscapes climate change is projected to induce a shift in forest composition, with drought-sensitive species, such as Norway spruce, being replaced by more drought-tolerant species such as Scots pine and black pine at lower elevations. In the higher elevation landscape a reduction in spruce growth is projected, particularly under the more severe climate change scenarios. Under most climate scenarios a reduction in growing stock is projected to occur, but under some scenarios a moderate increase in higher elevation stands (>1500 m a.s.l.) is expected. Climate change is projected to negatively influence carbon storage potential across landscapes with the magnitude depending on the severity of the climate change scenario. The impact of climate change on forest diversity and habitat availability is projected to differ considerably between the two landscapes, with diversity and habitat quality generally increasing at higher elevations, and being reduced at lower elevations. Our results suggest that if currently management practices are maintained the sensitivity of forests and forest ecosystem services in the Western Rhodopes to climate change will differ between low and higher elevation sites and will depend strongly on current forest composition.  相似文献   
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Sediment samples and soils along the coast line of the Adriatic Sea were sampled along a transect near the coast line at Zadar/Croatia, ranging from north-western suburbs via the historical centre and the industrial area to south-east suburbs. The sediments were dominated by carbonates and clay minerals, and contaminations with Cd–Cu–Pb–Zn–TOC (total organic carbon) at the historical centre and the industrial site were detected, as well as P and Mo input at the mouth of a small creek, probably from agriculture. No trends between the composition of surface and subsurface sea sediments were seen. At the historic harbour site, total element concentrations versus grain size showed a minimum in the fine silt fraction for most of the elements analysed. The soil samples behind the shoreline were not carbonaceous, but dominated by Fe–Al– oxides, some contained high levels of Be–Cd–Cu–Sn–Zn. Surprisingly, high TOC values within the soils might be assigned to human impacts, not to humus. Contrary to data from street dust samples from Seoul city/Korea, which were measured within our laboratory at the same time, Pt–Ir–Au were at ambient levels due to the limited use of catalysts in cars in the Zadar area at the time of sampling.  相似文献   
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Literature data on numerical values obtained for the parameters of the two most popular models for simulating the migration of radionuclides in undisturbed soils have been compiled and evaluated statistically. Due to restrictions on the applicability of compartmental models, the convection–dispersion equation and its parameter values should be preferred. For radiocaesium, recommended values are derived for its effective convection velocity and dispersion coefficient. Data deficiencies still exist for radionuclides other than caesium and for soils of non-temperate environments.  相似文献   
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The concentration of uranium was determined in 944 samples from stream water by the inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) method and represented on a color-shaded contour map. Uranium concentrations in surface water were determined to be between 0.007 μg/l and 43.7 μg/l with median of 0.33 μg/l. The regional distribution of uranium is influenced primarily by lithological and anthropogenic factors. In Mecklenburg, northern Brandenburg, and eastern Schleswig-Holstein, elevated uranium concentrations coincide with the extent of the last Weichselian ice sheet. The maximum concentrations are observed in the surface waters of the old mining districts in the western part of the Ore Mountains and in eastern Thuringia. Elevated concentrations are found in areas of agriculturally used loess soils. These concentrations correlate with the use of phosphate fertilizers. There is a zone of elevated concentrations up to 10.0 μg U/l in the Keuper Sandstone area south of the Thuringian Forest and from northwest of Stuttgart as far as Coburg. The distribution of elevated values in mineral water shows a clear correlation with the elevated values in surface water and the geology of those locations. Bunter and Keuper strata are the most important uranium source.  相似文献   
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Eighteen representative sites for the Austrian grain-growing and eight for the potato-growing zones (soils and crops) were investigated. On each site, total element contents (B, Ba, Ca, Cd, Co, Cu, Fe, K, Li, Mg, Mn, Mo, Na, P, Sr and Zn) were determined in 4–12 varieties of winter wheat (n = 136), 6 varieties of spring durum wheat (n = 30), 5 varieties of winter durum wheat (n = 15), 7 varieties of rye (n = 49), 5 varieties of spring barley (n = 30) and 5 varieties of potatoes (n = 40). Element accumulations in grain species and potato tubers varied significantly with site conditions, with the main exceptions for B in potatoes and wheat as well as for Zn, Cu and Co in durum wheat. On average, across all investigated sites, differences in varieties occurred concerning the elements Ca, Cd, Ba, Sr and Zn (except Zn in potatoes and winter durum). A rough estimation revealed that an average Austrian consumer of wheat, rye and potatoes meets more than 50% of the needs of daily element intake for K, P and Mg, between 36 and 72% for Fe, Zn and Cu, and more than 100% for Co, Mo and Mn. In particular, the elements Ca and Na have to be added from other sources.  相似文献   
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We present climate change projections and apply indices of weather extremes for the Mediterranean island Cyprus using data from regional climate model (RCM) simulations driven by the IPCC A1B scenario within the ENSEMBLES project. Daily time-series of temperature and precipitation were used from six RCMs for a reference period 1976–2000 and for 2026–2050 (‘future‘) for representative locations, applying a performance selection among neighboring model grid-boxes. The annual average temperatures of the model ensemble have a ±1.5°C bias from the observations (negative for maximum and positive for minimum temperature), and the models underestimate annual precipitation totals by 4–17%. The climatological annual cycles for the observations fall within the 1σ range of the 6-model average, highlighting the strength of using multi-model output. We obtain reasonable agreement between models and observations for the temperature-related indices of extremes for the recent past, while the comparison is less good for the precipitation-related extremes. For the future, the RCM ensemble shows significant warming of 1°C in winter to 2°C in the summer for both maximum and minimum temperatures. Rainfall is projected to decrease by 2–8%, although this is not statistically significant. Our results indicate the shift of the mean climate to a warmer state, with a relatively strong increase in the warm extremes. The precipitation frequency is projected to decrease at the inland Nicosia and at the coastal Limassol, while the mountainous Saittas could experience more frequent 5–15 mm/day rainfall. In future, very hot days are expected to increase by more than 2 weeks/year and tropical nights by 1 month/year. The annual number of consecutive dry days shows a statistically significant increase (of 9 days) in Limassol. These projected changes of the Cyprus climate may adversely affect ecosystems and the economy of the island and emphasize the need for adaptation strategies.  相似文献   
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The international, interdisciplinary biodiversity research project BIOTA AFRICA initiated a standardized biodiversity monitoring network along climatic gradients across the African continent. Due to an identified lack of adequate monitoring designs, BIOTA AFRICA developed and implemented the standardized BIOTA Biodiversity Observatories, that meet the following criteria (a) enable long-term monitoring of biodiversity, potential driving factors, and relevant indicators with adequate spatial and temporal resolution, (b) facilitate comparability of data generated within different ecosystems, (c) allow integration of many disciplines, (d) allow spatial up-scaling, and (e) be applicable within a network approach. A BIOTA Observatory encompasses an area of 1?km2 and is subdivided into 100 1-ha plots. For meeting the needs of sampling of different organism groups, the hectare plot is again subdivided into standardized subplots, whose sizes follow a geometric series. To allow for different sampling intensities but at the same time to characterize the whole square kilometer, the number of hectare plots to be sampled depends on the requirements of the respective discipline. A hierarchical ranking of the hectare plots ensures that all disciplines monitor as many hectare plots jointly as possible. The BIOTA Observatory design assures repeated, multidisciplinary standardized inventories of biodiversity and its environmental drivers, including options for spatial up- and downscaling and different sampling intensities. BIOTA Observatories have been installed along climatic and landscape gradients in Morocco, West Africa, and southern Africa. In regions with varying land use, several BIOTA Observatories are situated close to each other to analyze management effects.  相似文献   
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This paper presents an application of a modified ecological footprint method, using a regional, disturbance-based approach. In contrast to conventional institutional ecological footprint calculations, energy and land use resulting from all upstream production processes are explored by employing an input-output framework. Ecological footprints are calculated for two research institutions: the School of Physics (SoP) at the University of Sydney, and the Sustainable Ecosystems (CSE) Department of the Commonwealth Scientific and Industrial Research Organisation. These are broken down further in terms of land disturbance and greenhouse gas emissions, and as a function of production layer. To enable the use of the results in policy formulation, the ecological footprints are decomposed into detailed contributing paths, which are ranked according to their importance, using structural path analysis. The paper demonstrates that a considerable proportion of impacts occur upstream in industrial production. Thus a significant result of the study is the weight of obscure paths in the total footprints and, therefore, the importance of conducting an holistic assessment in order to ensure all upstream contributions are captured in the final impact of the institution.  相似文献   
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