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471.
Bjørn Kløve Pertti Ala-aho Guillaume Bertrand Zuzana Boukalova Ali Ertürk Nico Goldscheider Jari Ilmonen Nusret Karakaya Hans Kupfersberger Jens Kvœrner Angela Lundberg Marta Mileusni? Agnieszka Moszczynska Timo Muotka Elena Preda Pekka Rossi Dmytro Siergieiev Josef Šimek Przemys?aw Wachniew Vadineanu Angheluta Anders Widerlund 《Environmental Science & Policy》2011,14(7):770-781
Groundwater dependent ecosystems (GDEs) include valuable ecosystems such as springs, wetlands, rivers, lakes and lagoons. The protection of these systems and services they provide is highlighted by international agreements, i.e. Ramsar convention on wetlands, and regional legislation, i.e. the European Water Framework Directive. Groundwater provides water, nutrients and a relatively stable temperature. However, the role of groundwater in surface ecosystems is not fully understood. The ecosystem can depend on groundwater directly or indirectly, and the reliance can be continuous, seasonal or occasional. This has implications for the vulnerability of ecosystems, as some may be easily affected by external pressure. Conceptual models and quantitative assessments of how groundwater interacts with the environment are needed. GDEs are also threatened by different land use activities and climate change. Hence, we need to understand how GDEs are affected by changes in groundwater quantity and quality, as severe groundwater changes have been observed in many regions. This study examines key aspects of GDEs (hydrogeology, geochemistry and biodiversity) in order to improve conceptual understanding of the role of groundwater in such ecosystems. The status and baseline of different types of GDEs are discussed, with particular emphasis on past evidence of environmental change and potential thresholds and threats in GDEs in various parts of Europe with different land use, climate and geology. 相似文献
472.
为探讨榆树市土壤中各种元素的地球化学特征,利用GPS野外定点采取榆树市表层及深层土壤样品,采用XRF-X荧光光谱法测定土壤元素的组成及含量,运用SPSS和EXCELL2003软件对榆树市土壤元素地球化学特征进行分析。结果表明:研究区土壤必需的大量元素含量分布规律为Al>K>Ca>Mg>N>P;土壤必需的微量元素含量具有Fe>Mn>Zn>B>Cu>Mo的特征;土壤有益元素含量具有Si>Na>Ni>Co的区域特征;土壤健康元素含量具有F>I>Se的区域特征。运用内梅罗综合指数法计算土壤污染指数,查明营养元素丰缺状况。结果表明:研究区综合污染指数为0.66,总体上属于背景水平,符合一级土壤环境质量标准,适宜种植多种农作物。 相似文献
473.
Soil erosion induced by land use changes as determined by plough marks and field evidence in the Aksum area (Ethiopia) 总被引:1,自引:0,他引:1
Rossano Ciampalini Paolo BilliGiovanni Ferrari Lorenzo BorselliStéphane Follain 《Agriculture, ecosystems & environment》2012,146(1):197-208
The aim of the research presented here was to analyse soil erosion in response to changes in agricultural and soil conservation practices throughout history. The Aksum area (Tigray, northern Ethiopia) presents favourable conditions for the development of a long-term approach for assessing soil conservation techniques that have been applied for centuries (i.e., since the Aksumite kingdom, 400 BC to 800 AD). These techniques have been maintained until the present day, and parts of the terraced systems of the area are still in use. During the 1970s, social and political events led to a remarkable change in land use patterns, and large arable areas were converted into grazing land, resulting in a significant increase in soil loss. The rates of soil erosion were evaluated based on analyses of the deep scratches (plough marks) left on stones in the soil by the maresha, the ard plough pulled by oxen used in agricultural practices of the area, and the patinas, varnishes and weathering rinds exposed by soil loss after the abandonment of the fields. The study results show average rates of soil erosion of 2.8 t ha−1 y−1 and 65.8 t ha−1 y−1 for the soil conservation conditions under traditional agriculture (long-term observations) and accelerated erosion after abandonment (short-term observations), respectively. A comparison using recently calibrated erosion evaluation techniques conducted to support the field measurements revealed a close correlation between the calculated and recorded data. 相似文献
474.
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476.
Implementing Ecosystem Management in Public Agencies: Lessons from the U.S. Bureau of Land Management and the Forest Service 总被引:1,自引:0,他引:1
Abstract: Ecosystem management was formally adopted over a decade ago by many U.S. natural resource agencies, including the Forest Service and the Bureau of Land Management. This approach calls for management based on stakeholder collaboration; interagency cooperation; integration of scientific, social, and economic information; preservation of ecological processes; and adaptive management. Results of previous studies indicate differences in the extent to which particular components of ecosystem management would be implemented within the U.S. Forest Service and the Bureau of Land Management and suggest a number of barriers thought to impede implementation. Drawing on survey and interview data from agency personnel and stakeholders, we compared levels of ecosystem-management implementation in the Forest Service and Bureau of Land Management and identified the most important barriers to implementation. Agency personnel perceived similarly high levels of implementation on many ecosystem-management components, whereas stakeholders perceived lower levels. Agencies were most challenged by implementation of preservation of ecological processes, adaptive management, and integration of social and economic information, whereas the most significant barriers to implementation were political, cultural, and legal. 相似文献
477.
As coastal populations expand, demands for recreational opportunities on beaches and coastal dunes grow correspondingly. Although
dunes are known to be sensitive to direct human disturbance and provide irreplaceable ecosystem services (e.g. erosion control,
critical habitat and nesting sites), dunes serve as campsites for large numbers of people (∼90,000 p.a.) on the ocean-exposed
shores of Fraser Island, Australia. Campsites are located in the established dunes and can only be accessed with 4WD vehicles
along tracks cut directly from the beach through the foredunes. Here we quantified the extent of physical damage to foredunes
caused by this practice, and tested whether human-induced physical changes to foredunes translate into biological effects.
Of the 124 km of ocean-exposed beaches, 122 km (98%) are open to vehicles driven on the beaches, and camping zones cover 28.7
km or 23% of the dunes. A total of 235 vehicle tracks are cut across the foredunes at an average density of eight tracks per
km of beach. These tracks have effectively destroyed one-fifth (20.2%) of the dune front in camping zones, deeply incising
the dune-beach interface. There is evidence of accelerated erosion and shoreline retreat centred around vehicle tracks, resulting
in a “scalloping” of the shoreline. No dune vegetation remains in the tracks and the abundance of ghost crabs (Ocypode spp.) is significantly reduced compared with the abutting dunes. Because current levels of environmental change caused by
dune camping may not be compatible with the sustainable use of coastal resources and conservation obligations for the island
(listed as a World Heritage Area and gazetted as a National Park), restoration and mitigation interventions are critical.
These will require spatial prioritisation of effort, and we present a multi-criteria ranking method, based on quantitative
measures of environmental damage and ecological attributes, to objectively target rehabilitation and conservation measures.
Ultimately, coastal management needs to develop and implement strategies that reconcile demands for human recreation, including
beach camping, with conservation of coastal dune ecosystems. 相似文献
478.
Particle size distribution and pollutants in road-deposited sediments in different areas of Zhenjiang,China 总被引:2,自引:0,他引:2
An understanding of road-deposited sediment (RDS) characteristics on an impervious surface is essential to estimate pollutant
washoff characteristics and to minimise the impacts of pollutants on the water environment. A total of 62 RDS samples were
collected from four different land-use types (commercial, residential, intense traffic and riverside park) in Zhenjiang City,
China. The samples were fractionated into seven grain-size classes and analysed for particle size distribution and concentrations
of pollutants. The samples are found to consist predominantly of fine particles (60–80%, <250 μm). The maximum mean concentrations
of zinc, lead and copper were 686.93, 589.19 and 158.16 mg/kg, respectively, with the highest metal concentrations found in
samples from the intense traffic area. The maximum mean contents of organic matter (12.55%), nitrogen (6.31 mg/g) and phosphorus
(5.15 mg/g) were found in samples from the commercial area. The concentrations of heavy metals were highest in the smallest
particle size fraction analysed (63 μm). The organic matter and nitrogen content generally increased with decreasing particle
sizes in the <500-μm particle size range. The results also revealed that most of the total nitrogen (TN) is attached to the
finer sediments and that to effectively reduce TN loads in particulates, treatment facilities must be able to remove the finer
particles (down to 125 μm for TN). 相似文献
479.
From meso- to macro-scale dynamic water quality modelling for the assessment of land use change scenarios 总被引:3,自引:0,他引:3
Shaochun Huang Cornelia Hesse Valentina Krysanova Fred Hattermann 《Ecological modelling》2009,220(19):2543-2558
The implementation of the European Water Framework Directive requires reliable tools to predict the water quality situations in streams caused by planned land use changes at the scale of large regional river basins. This paper presents the results of modelling the in-stream nitrogen load and concentration within the macro-scale basin of the Saale river (24,167 km2) using a semi-distributed process-based ecohydrological dynamic model SWIM (Soil and Water Integrated Model). The simulated load and concentration at the last gauge of the basin show that SWIM is capable to provide a satisfactory result for a large basin. The uncertainty analysis indicates the importance of realistic input data for agricultural management, and that the calibration of parameters can compensate the uncertainty in the input data to a certain extent. A hypothesis about the distributed nutrient retention parameters for macro-scale basins was tested aimed in improvement of the simulation results at the intermediate gauges and the outlet. To verify the hypothesis, the retention parameters were firstly proved to have a reasonable representation of the denitrification conditions in six meso-scale catchments. The area of the Saale region was classified depending on denitrification conditions in soil and groundwater into three classes (poor, neutral and good), and the distributed parameters were applied. However, the hypothesis about the usefulness of distributed retention parameters for macro-scale basins was not confirmed. Since the agricultural management is different in the sub-regions of the Saale basin, land use change scenarios were evaluated for two meso-scale subbasins of the Saale. The scenario results show that the optimal agricultural land use and management are essential for the reduction in nutrient load and improvement of water quality to meet the objectives of the European Water Framework Directive and in view of the regional development plans for future. 相似文献
480.
《Environmental Hazards》2013,12(3):200-210
Superstorm Sandy made landfall in New Jersey on 29 October 2012, leaving tens of thousands homeless, businesses destroyed, and 90% of New Jersey residents without electricity. Widespread infrastructure and property damage, health-related issues, and social dislocations still remain among the challenges. We interviewed 756 people in central and coastal New Jersey to ascertain damage levels, what they would do differently next time, and what governments should do differently. To deal with future events, people thought that they should prepare, buy generators and other supplies, and evacuate sooner. Their actions dealt with preparedness, rather than recovery or resiliency. However, the subjects felt that governmental agencies also had a responsibility for emergency actions, recovery, and resiliency. Preparedness included better warnings and helping to prepare homes for the impending storm. During the storm, people thought government should have faster evacuations, communications, and provide shelter, security, and supplies. Recovery included providing gas and generators, restoring electricity, providing money, and quicker response by FEMA and insurance companies. People thought the government should ensure resiliency of their communities by allowing no beach-front homes, having better building standards, and restoring dunes. Coastal people suffered greater damage for longer, and voiced a higher sense of wanting government actions. 相似文献