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351.
Stefan Mann 《Journal of Environmental Planning and Management》2004,47(4):541-554
The Contingent Valuation Method (CVM) and other conventional valuation methods of non‐market goods often prove to be unsuitable for the evaluation of the benefits of agro‐environmental policy. Therefore, a new method is introduced, according to which a group of experts jointly evaluates the strengths, weaknesses and finally monetary benefit of agro‐environmental programmes. While the methodology combines expert surveys, group discussions and CVM, its theoretical background is merit good theory. Compared to CVM, the most important practical difference in its outcome is the greater openness of the results. As an example, the Expert Valuation Method is applied to two groups of agro‐environmental policy measures in Switzerland. Suggestions for more efficient levels of reimbursements are made. 相似文献
352.
Mark J. Hanson Heinz G. Stefan 《Journal of the American Water Resources Association》1984,20(6):889-900
The shallow Fairmont Lakes in southern Minnesota have been treated with copper sulfate for 58 years to reduce excessive algal growth. Copper sulfate was applied to five lakes at cumulative rates upo to 1647 kg/ha (1470 1b/acre), totaling 1.5 million kilograms. Data collected since treatment of the Fairmont Lakes began in 1921 provide alarming insights into lake responses to sustained chemical treatment with copper sulfate. Short-term and long-term effects have occurred. Short-term effects include: a) the intended temporary killing of algae, b) dissolved oxygen depletion by decomposition of dead algae, c) accelerated phosphorus recycling from the lake bed and recovery of the algal population within 7 to 21 days, and d) occasional fish kills due to oxygen depletion or copper toxicity or both. Long-term effects are shown to include: a) copper accumulation in the sediments, b) tolerance adjustments of certain species of algae to higher copper sulfate dosages, c) shift of species from green to blue-green algae and from game fish to rough fish, d) disappearance of macrophytes, and e) reductions in benthic macroinvertebrates. The conclusion is that while copper sulfate treatments enjoy great popularity because they kill and remove algae almost instantaneously, other immediate or cumulative side effects can be harmful to many other aquatic organisms. 相似文献
353.
354.
Stefan Münzer Hubert D. Zimmer Maximilian Schwalm Jrg Baus Ilhan Aslan 《Journal of environmental psychology》2006,26(4):300-308
The incidental acquisition of spatial orientation knowledge when using a pedestrian navigation assistance system for wayfinding was compared to incidental learning during map-based wayfinding. First-time visitors to a real environment (a zoo) took a guided tour. In the navigation assistance conditions, users were provided with direction information and view-based pictures of the current intersection at each decision point, presented on a hand-held computer. In the map-based condition, participants derived route segments from a map (each segment comprising three or four intersections), and then walked the partial routes from memory. After walking, unexpected tests on route memory and survey knowledge were administered. Navigation assistance users showed good route knowledge and poor survey knowledge. In contrast, map users showed better survey knowledge and nearly perfect route knowledge. Variations of information presentation within navigation assistance conditions (auditory vs. visual direction command, additional presentation of allocentric spatial information) was not effective. Results are explained with an active encoding principle. Only information that is actually encoded, transformed, and/or memorized during the primary wayfinding activity, is incidentally learned. Since navigation assistance systems do not require users to encode, transform, and memorize spatial information, the spatial orientation knowledge of navigation assistance users is poor. 相似文献
355.
Stefan Gabriel 《International journal of occupational safety and ergonomics》2006,12(1):101-104
German employers' liability insurance associations or Berufsgenossenschaften (BGs)--institutions for statutory accident insurance--maintain a measurement system for hazardous substances, the so-called BGMG. The aim of the BGMG is to determine and document valid results of measurements of exposure primarily for prevention purposes. The data are collected systematically, in parallel to the sampling in a company. Parameters which are supposed to have a visible effect on exposure levels are documented. The MEGA database (documentation of measurement data relating to workplace exposure to hazardous substances) holds 1,629 million measurement values, which have been compiled in since 1972. The database offers a host of selection possibilities for assessments depending on the evaluation strategy. 相似文献
356.
Projected Climate Change Effects on Winterkill in Shallow Lakes in the Northern United States 总被引:1,自引:0,他引:1
2 was obtained from the output of the Canadian Climate Center General Circulation Model. To illustrate the effect of projected
climate change on lake DO characteristics, we present herein DO information simulated, respectively, with inputs of past climate
conditions (1961–1979) and with a projected 2 × CO2 climate scenario, as well as differences of those values. Specific parameters obtained were minimum under-ice and lake bottom
DO concentration in winter, duration of under-ice anoxic conditions (<0.1 mg/liter) and low DO conditions (<3 mg/liter), and
percentage of anoxic and low DO lake volumes during the ice cover period. Under current climate conditions winterkill occurs
typically in shallow eutrophic lakes of the northern contiguous United States. Climate warming is projected to eliminate winterkill
in these lakes. This would be a positive effect of climate warming. Fish species under ice may still experience periods of
stress and zero growth due to low DO (<3 mg/liter) conditions under projected climate warming. 相似文献
357.
Reinhard Mechler Stefan Hochrainer Asbjørn Aaheim Håkon Salen Anita Wreford 《Mitigation and Adaptation Strategies for Global Change》2010,15(7):737-762
Adaptation to climate change in Europe has only recently become a true policy concern with the management of extreme events
one priority item. Irrespective of future climatic changes increasing the need for systematic evaluation and management of
extremes, weather-related disasters already today pose substantial burdens for households, businesses and governments. Research
in the ADAM project identified substantial direct risks in terms of potential crop and asset losses due to combined drought
and heatwave, as well as flood hazards in Southern and Eastern Europe, respectively. This paper focuses on the indirect, medium
to longer term economic risks triggered by the direct risks and mediated by policy responses. We present a selection of three
economic impact and adaptation assessments and modelling studies undertaken on extreme event adaptation in Europe. Responding
to a need for more economically based adaptation assessments, we address some relatively unresearched issues such as the understanding
of past adaptation, the role of market response to impacts as well as government’s ability to plan for and share out extreme
event risks. The first analysis undertakes an empirical exploration of observed impacts and adaptation in the agricultural
sector in the UK comparing the impact of consecutive extreme events over time in order to determine whether adaptation has
occurred in the past and whether this can be used to inform future estimates of adaptation rates. We find that farmers and
the agricultural sector clearly have adapted to extreme events over time, but whether this rate can be maintained into the
future is unclear, as some autonomous adaptation enacted seemed rather easy to be taken. Markets may mediate or amplify impacts
and in the second analysis, we use an economic general equilibrium model to assess the economic effects of a reduction in
agricultural production due to drought and heatwave risk in exposed regions in Spain. The analysis suggests that modelled
losses to the local economy are more serious in a large-scale scenario when neighbouring provinces are also affected by drought
and heatwave events. This is due to the supply-side induced price increase leading to some passing on of disaster costs to
consumers. The simulation highlights the importance of paying particular attention to the spatial and distributional effects
weather extremes and possibly changes therein induced by climate change may incur. Finally, we discuss how national governments
may better plan their disaster liabilities resulting from a need to manage relief and reconstruction activities post event.
We do so using a risk based economic planning model assessing the fiscal consequences associated with the coping with natural
extremes. We identify large weather-related disaster contingent liabilities, particularly in the key flood hot spot countries
Austria, Romania, and Hungary. Such substantial disaster liabilities (“hidden disaster deficits”) when interacting with weak
fiscal conditions may lead to substantial additional stress on government budgets and reduced fiscal space for funding other
relevant public investment projects. Overall, our paper suggests the importance of respecting the specific spatial and temporal
characteristics of extreme event risk when generating information on adaptation decisions. As our adaptation decisions considered,
such as using sovereign risk financing instruments are associated with a rather short time horizon, the analysis largely focuses
on the management of today’s extreme events and does not discuss in detail projections of risks into a future with climate
change. Such projections raise important issues of uncertainty, which in some instances may actually render future projections
non-robust, a constraint to be kept in mind when addressing longer term decisions, which at the same time should account for
both climate and also socioeconomic change. 相似文献
358.
Stefan Hochrainer Reinhard Mechler Georg Pflug 《Mitigation and Adaptation Strategies for Global Change》2009,14(3):231-250
This paper discusses the applicability of crop insurance for the case of Malawi and explores the potential impact of climate
change on the viability of the Malawi weather insurance program making use of scenarios of climate change-induced variations
in rainfall patterns. The analysis is important from a methodological and policy perspective. By combining catastrophe insurance
modeling with climate modeling, the methodology demonstrates the feasibility, albeit with large uncertainties, of estimating
the effects of climate variability and climate change on the near- and long-term future of microinsurance schemes serving
the poor. By providing a model-based estimate of insurance back-up capital necessary to avoid ruin under climate variability
and climate change, along with the associated uncertainties and data limitations, this methodology can quantitatively demonstrate
the need for financial assistance to protect micro-insurance pools against climate-induced insolvency. This is of major concern
to donors, NGOs and others supporting these innovative systems, those actually at-risk and insurers providing insurance. A
quantitative estimate of the additional burden that climate change imposes on weather insurance for poor regions is of interest
to organizations funding adaptation. Further, by linking catastrophe modeling to regionalized climate modeling, the analysis
identifies key modeling inputs necessary as well as important constraints. We end with a discussion of the opportunities and
limits to similar modeling and weather predictability for Sub-Saharan Africa beyond the case of Malawi.
相似文献
Reinhard MechlerEmail: |
359.
S. Bringezu H. Schütz K. Arnold F. Merten S. Kabasci P. Borelbach C. Michels G.A. Reinhardt N. Rettenmaier 《Journal of Cleaner Production》2009
The global land area required to meet the German consumption of agricultural products for food and non-food use was quantified, and the related greenhouse gas (GHG) emissions, particularly those induced by land-use changes in tropical countries, were estimated. Two comprehensive business-as-usual scenarios describe the development corridor of biomass for non-food use in terms of energetic and non-energetic purposes. In terms of land use, Germany was already a net importer of agricultural land in 2004, and the net additional land required by 2030 is estimated to comprise 2.5–3.4 Mha. This is mainly due to biofuel demand driven by current policy targets. Meeting the required biodiesel import demand would result in an additional GWP of 23–37 Tg of CO2 equivalents through direct and indirect land-use changes. Alternative scenario elements outline the potential options for reducing Germany's land requirement, which reflect future global per capita availability. 相似文献
360.
Lindström ES Eiler A Langenheder S Bertilsson S Drakare S Ragnarsson H Tranvik LJ 《Ecology》2007,88(1):252-3; discussion 253-5