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1.
Environmental Science and Pollution Research - Bisphenol-A is widely used chemical in industry and unfortunately often detected in natural waters. Considered as an emerging pollutant, bisphenol-A...  相似文献   
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The fate of hydrophobic organic compounds (HOCs) in soils and waters in a northern boreal catchment was explored through the development of a chemical fate model in a well-characterised catchment system dominated by two land types: forest and mire. Input was based solely on atmospheric deposition, dominated by accumulation in the winter snowpack. Release from soils was governed by the HOC concentration in soil, the soil organic carbon fraction and soil-water DOC content. The modelled export of selected HOCs in surface waters ranged between 11 and 250 ng day−1 during the snow covered period, compared to 200 and 9600 ng/d during snow-melt; highlighting the importance of the snow pack as a source of these chemicals. The predicted levels of HOCs in surface water were in reasonable agreement to a limited set of measured values, although the model tended to over predict concentrations of HOCs for the forested sub-catchment, by over an order of magnitude in the case of hexachlorobenzene and PCB 180. This possibly reflects both the heterogeneity of the forest soils and the complicated and changing hydrology experienced between the different seasons.  相似文献   
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A resource allocation trade-off is expected when resources from a common pool are allocated to two or more traits. In holometabolous insects, resource allocation to different functions during metamorphosis relies completely on larval-derived resources. At adult eclosion, resource allocation to the abdomen at the expense of other body parts can be seen as a rough estimate of resource allocation to reproduction. Theory suggests geographic variation in resource allocation to the abdomen, but there are currently no empirical data on it. We measured resource allocation to the abdomen at adult eclosion in four geometrid moths along a latitudinal gradient. Resource (total dry material, carbon, nitrogen) allocation to the abdomen showed positive allometry with body size. We found geographic variation in resource allocation to the abdomen in each species, and this variation was independent of allometry in three species. Geographic variation in resource allocation to the abdomen was complex. Resource allocation to the abdomen was relatively high in partially bivoltine populations in two species, which fits theoretical predictions, but the overall support for theory is weak. This study indicates that the geographic variation in resource allocation to the abdomen is not an allometric consequence of geographic variation in resource acquisition (i.e., body size). Thus, there is a component of resource allocation that can evolve independently of resource acquisition. Our results also suggest that there may be intraspecific variation in the degree of capital versus income breeding.  相似文献   
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Shrubs and trees are expected to expand in the sub-Arctic due to global warming. Our study was conducted in Abisko, sub-arctic Sweden. We recorded the change in coverage of shrub and tree species over a 32– to 34-year period, in three 50 × 50 m plots; in the alpine-tree-line ecotone. The cover of shrubs and trees (<3.5 cm diameter at breast height) were estimated during 2009–2010 and compared with historical documentation from 1976 to 1977. Similarly, all tree stems (≥3.5 cm) were noted and positions determined. There has been a substantial increase of cover of shrubs and trees, particularly dwarf birch (Betula nana), and mountain birch (Betula pubescens ssp. czerepanovii), and an establishment of aspen (Populus tremula). The other species willows (Salix spp.), juniper (Juniperus communis), and rowan (Sorbus aucuparia) revealed inconsistent changes among the plots. Although this study was unable to identify the causes for the change in shrubs and small trees, they are consistent with anticipated changes due to climate change and reduced herbivory.  相似文献   
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Drainage of forested wetlands for increased timber production has profoundly altered the hydrology and water quality of their downstream waterways. Some ditches need network maintenance (DNM), but potential positive effects on tree productivity must be balanced against environmental impacts. Currently, no clear guidelines exist for DNM that strike this balance. Our study helps begin to prioritise DNM by: (1) quantifying ditches by soil type in the 68 km2 Krycklan Catchment Study in northern Sweden and (2) using upslope catchment area algorithms on new high-resolution digital elevation models to determine their likelihood to drain water. Ditches nearly doubled the size of the stream network (178–327 km) and 17% of ditches occurred on well-draining sedimentary soils, presumably making DNM unwarranted. Modelling results suggest that 25–50% of ditches may never support flow. With new laser scanning technology, simple mapping and modelling methods can locate ditches and model their function, facilitating efforts to balance DNM with environmental impacts.  相似文献   
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Protecting water quality in forested regions is increasingly important as pressures from land-use, long-range transport of air pollutants, and climate change intensify. Maintaining forest industry without jeopardizing sustainability of surface water quality therefore requires new tools and approaches. Here, we show how forest management can be optimized by incorporating landscape sensitivity and hydrological connectivity into a framework that promotes the protection of water quality. We discuss how this approach can be operationalized into a hydromapping tool to support forestry operations that minimize water quality impacts. We specifically focus on how hydromapping can be used to support three fundamental aspects of land management planning including how to (i) locate areas where different forestry practices can be conducted with minimal water quality impact; (ii) guide the off-road driving of forestry machines to minimize soil damage; and (iii) optimize the design of riparian buffer zones. While this work has a boreal perspective, these concepts and approaches have broad-scale applicability.  相似文献   
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The copper (Cu) resistance of Arctostaphylos uva-ursi was tested in a pot experiment (lasting 8 weeks) using rooted cuttings originating from an area near the Harjavalta Cu-Ni smelter, SW Finland. The fine roots were moderately infected by arbutoid mycorrhizae. The plants were exposed to five Cu levels (1, 10, 22, 46 and 100 mg l(-1)) given repeatedly together with a nutrient solution. The critical Cu concentration in the nutrient solution inhibiting the growth of A. uva-ursi was below 10 mg l(-1) Cu (EC(50) value for biomass production 3.3 mg l(-1) Cu). This concentration was clearly lower than the value we have found earlier for other dwarf shrubs under similar experimental conditions. Most of the Cu given accumulated in the roots and old stems. The results suggest that A. uva-ursi cuttings were relatively sensitive to Cu despite the ability of the adult clones to grow in Cu-contaminated soil. The adult clones extend their roots into the less toxic deeper soil layers, which may facilitate the avoidance of heavy metals.  相似文献   
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The effects of long-term enhanced UV-B radiation on growth and secondary compounds of two conifer species were studied in an outdoor experiment. Scots pine (Pinus sylvestris) seedlings were exposed for two growing seasons and Norway spruce (Picea abies) seedlings for three growing seasons to supplemental UV-B radiation, corresponding to a 30% increase in ambient UV-B radiation. The experiment also included appropriate controls for ambient and increased UV-A radiation. Enhanced UV-B did not affect the growth of the conifer seedlings. In addition, neither the concentrations of terpenes and phenolics in the needles nor the concentrations of terpenes in the wood were affected. However, in the UV-A control treatment the concentrations of diterpenes in the wood of Scots pine decreased significantly compared to the ambient control. Apparently, a small increase in UV-B radiation has no significant effects on the secondary compounds and growth of Scots pine and Norway spruce seedlings.  相似文献   
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Human factors (HF) in creating and managing safety in complex systems is a continuous topic of research and discussion. In the aviation organisation under study here, an HF expert had started work in a newly created position one and a half years prior to the study. The aim of the study was to find out if HF was seen as a safety creating factor and what the conceptions of HF were in regard to the theoretical developments in the field. These topics were studied in order to determine the most effective means of implementing HF-work within the organisation. Two manager groups (upper and middle management) were targeted as subjects of the study due to their crucial role in developing working culture. Twenty-one managers were interviewed from nine units that represented three operational environments (radar units with heavy traffic, combined civil/military units and procedural air traffic control units, including airport operations. Managers were found to have disjointed and vague conceptions of HF and a lack of shared vision or strategy regarding HF. Some managers lacked an appropriate conception of HF. The present situation can prevent the organisation from utilizing HF competence in maintaining and developing the safety of services. Conceptions were most up-to-date at units, where outside pressures for change had forced managers to take HF issues into account in their operational environments. While the long-term implementation of HF faces considerable challenges, the article gives several proposals for organisational structures that support a more effective realization of HF.  相似文献   
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