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871.
Behavioral adaptations of ant species were studied in associations of different biotopes in the Crimean Mountains. The pattern
of an association was found to depend on the mode of the territorial behavior of dominant species, irrespective of their number.
The dominance hierarchy was more strict in monodominant than in bidominant associations. Ant species demonstrated different
behavioral strategies, plasticity of foraging, and avoidance of aggressive encounters. A method for formalizing interspecies
relationships and a model describing stochastic properties of the biological system are proposed, which can be useful in solving
various ethological and ecological problems. 相似文献
872.
873.
The developing countries i.e., the non-Annex-I countries (parties to the Kyoto Protocol but not responsible to any reduction
target yet) in the Kyoto Protocol whose economies are in transition are also allowed to reduce GHG emissions. Among these,
the countries that have accepted the Kyoto Protocol may be benefited from CDM projects to promote sustainable development.
The developed countries i.e., the Annex-I countries (that have signed the Kyoto Protocol & are responsible to have specific
GHG emission reduction target) or the investing countries, in return, have privilege to purchase CER credits (in units equivalent
to one tonne of CO2 gas emission reduction) to meet the emission target as specified in the Kyoto Protocol. The key step in understanding about
CDM is to grasp the concept of “baseline” and “additionality”. The “Baseline” is the emissions level that would have existed if a CDM project had not happened. The feature of an approved CDM project
is that the planned reductions would not occur without the additional incentive provided by emission reduction credits; this
concept is known as “Additionality”. According to environmental additionality concept, baseline emission minus project emission is equal to emissions reduction.
“Investment Additionality,” ultimately rejected during negotiation of the “Marrakech Accords” and “Financial Additionality,” are the two important concepts. The concept of trading of CER matches to the idea of Pigovian tax (equal to the negative externality and which is considered one of the “traditional” means of bringing a modicum of market
forces) in Economics, making pollution more costly to the polluter, as the polluters have negative cost since they save money
by polluting; hence, there are supposed negative externalities associated with the market activity. Economic theory predicts
that in an economy where the cost of reaching mutual agreement between parties is high and where pollution is diffuse, Pigovian
tax will be an efficient way to promote the public interest and will lead to an improvement of the quality of life measured
by the Genuine Progress Indicator and other human economic indicators, as well as higher gross domestic product growth. We
can seek a level of pollution such that the marginal savings (MS) to one polluting unit from pollution (−MC) is equal to marginal
damage (MD) from pollution over the entire population, since pollution is a public bad i.e., MS (x*) = ∑MDi (x*) where ∑Di (x) is the total damage. Though the responsibility of reduction in emission does not lie on the non-Annex-I countries, still
effort of maintaining global emission balance can be expected equally from developed and developing countries. The responsibilities
of Kyoto Protocol are (a) to reduce global GHG emissions, (b) to bring about sustainable development in the developing countries
lie on above two groups since its effect on February 16, 2005. Different polluters have different costs of pollution control.
The least costly way of controlling pollution from various sources that reflects different costs of pollution control making
the set of environmental regulations to achieve the emission target at the lowest cost makes the regulation cost-effective.
Though efficiency is not attainable for many regulations, cost-effectiveness is attainable. 相似文献
874.
Matilda Palm Madelene Ostwald Indu K. Murthy Rajiv K. Chaturvedi N. H. Ravindranath 《Regional Environmental Change》2011,11(2):423-435
This paper analyses environmental and socio-economic barriers for plantation activities on local and regional level and investigates
the potential for carbon finance to stimulate the increased rates of forest plantation on wasteland, i.e., degraded lands,
in southern India. Building on multidisciplinary field work and results from the model GCOMAP, the aim is to (1) identify
and characterize the barriers to plantation activities in four agro-ecological zones in the state of Karnataka and (2) investigate
what would be required to overcome these barriers and enhance the plantation rate and productivity. The results show that
a rehabilitation of the wasteland based on plantation activities is not only possible but also anticipated by the local population
and would lead to positive environmental and socio-economic effects at a local level. However, in many cases, the establishment
of plantation activities is hindered by a lack of financial resources, low land productivity and water scarcity. Based on
the model used and the results from the field work, it can be concluded that certified emission reductions such as carbon
credits or other compensatory systems may help to overcome the financial barrier; however, the price needs to be significantly
increased if these measures are to have any large-scale impact. 相似文献
875.
Panos Hadjinicolaou Christos Giannakopoulos Christos Zerefos Manfred A. Lange Stelios Pashiardis Jos Lelieveld 《Regional Environmental Change》2011,11(3):441-457
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
876.
Christos Giannakopoulos Effie Kostopoulou Konstantinos V. Varotsos Kostas Tziotziou Achilleas Plitharas 《Regional Environmental Change》2011,11(4):829-843
Climate changes in the Mediterranean region, related to a significant increase in temperature and changes in precipitation
patterns, can potentially affect local economies. Agriculture and tourism are undoubtedly the most important economic sources
for Greece and these may be more strongly affected by changing future climate conditions. Climate change and their various
negative impacts on human life are also detected in their environment; hence this study deals with implications, caused by
changing climate, in urban and forest areas. Potential changes for the mid-twenty-first century (2021–2050) are analysed using
a high-resolution regional climate model. This paper presents relevant climatic indices, indicative for potential implications
which may jeopardise vital economic/environmental sectors of the country. The results provide insights into particular regions
of the Greek territory that may undergo substantial impacts due to climate change. It is concluded that the duration of dry
days is expected to increase in most of the studied agricultural regions. Winter precipitation generally decreases, whereas
an increase in autumn precipitation is projected in most areas. Changing climate conditions associated with increased minimum
temperatures (approximately 1.3°C) and decreased winter precipitation by 15% on average suggest that the risk for forest fires
is intensified in the future. In urban areas, unpleasantly high temperatures during day and night will increase the feeling
of discomfort in the citizens, while flash floods events are expected to occur more frequently. Another impact of climate
change in urban regions is the increasing energy demand for cooling in summer. Finally, it was found that continental tourist
areas of the Greek mainland will more often face heatwave episodes. In coastal regions, increased temperatures especially
at night in combination with high levels of relative humidity can lead to conditions that are nothing less than uncomfortable
for foreigners and the local population. In general, projected changes associated with temperature have a higher degree of
confidence than those associated with precipitation. 相似文献
877.
Ecosystem services and hydroelectricity in Central America: modelling service flows with fuzzy logic and expert knowledge 总被引:1,自引:0,他引:1
Bruno Locatelli Pablo Imbach Raffaele Vignola Marc J. Metzger Efraín José Leguía Hidalgo 《Regional Environmental Change》2011,11(2):393-404
Because ecosystem services are generally not produced and used in the same place, their assessment should consider the flows
of services from ecosystems to users. These flows depend on the characteristics and spatial distribution of ecosystems and
users, the spatial relationships between them, and the presence of filters or barriers between ecosystems and users. The objective
of this paper is to map the ecosystem services provided to the Costa Rican and Nicaraguan hydroelectric sectors, which are
crucial sectors for national sustainable development and depend directly on hydrological ecosystem services. The paper presents
an approach for modelling the flows of multiple services from diverse ecosystems to diverse users through different kinds
of filters in a landscape. The approach uses expert knowledge and fuzzy numbers to handle uncertainties. The analyses for
Costa Rica and Nicaragua show how the approach helps identify priority areas for the conservation and restoration of forests
for the services they provide to the hydroelectric sector. As such, it is a useful tool for defining spatially targeted policies
for the conservation of ecosystem services and for involving the users of ecosystem services in ecosystem management. 相似文献
878.
P. Valkering R. van der Brugge A. Offermans N. Rijkens-Klomp 《Regional Environmental Change》2011,11(2):229-241
Climate adaptation is a complex task surrounded by uncertainty. To support climate adaptation policies, a new scenario approach
is pursued to explore possible discontinuous future developments of societal perspectives on climate adaptation issues. The
scenario approach was tested for a case study on Dutch river management. In a series of scenario development workshops, a
select group of stakeholders explored the perspectives on the management of the River Meuse in the past, present, and future.
The process was supported by an analytical perspectives mapping tool to illustrate and analyze the development of perspectives
over time. The process and analytical tools contributed to insight into the drivers of perspective change for the case study
at hand. Moreover, the stakeholders highlighted the potential of the approach for water management policy for creating awareness
about the plurality of perspectives and the dynamics of perspective change, monitoring perspectives and perspective change
as part of a flexible policy approach, and anticipating on the occurrence of shock events. Further work is required to better
represent the social dynamics of perspectives change, to better empirically ground the perspective change model, and to apply
integrated water models in the scenario development process to assess water–society interactions. 相似文献
879.
Recent changes in flood preparedness of private households and businesses in Germany 总被引:6,自引:0,他引:6
Heidi Kreibich Isabel Seifert Annegret H. Thieken Eric Lindquist Klaus Wagner Bruno Merz 《Regional Environmental Change》2011,11(1):59-71
Using the focusing event framework, a comprehensive analysis of private households’ and businesses’ preparedness was undertaken in the aftermath of the 2002 and 2006 flood events on the Elbe River in Germany. In August 2002, preparedness of households (n = 235) and businesses (n = 103) was low: 30% of the households and 54% of the businesses took no precautionary measures before the flood event. Many undertaken emergency measures were ineffective, since only 26% of all households knew how to react when the flood warning came, and only 9% of businesses had an emergency plan in place. Due to this extreme flood, double-loop learning occurred in many households and businesses, so that many did implement precautionary measures. The distribution of adopted precautionary measures for households fits well to Preisendörfer’s low-cost hypothesis, but does not apply for businesses. Only 10% of the households (n = 112), but still 29% of the businesses (n = 41) were unprepared before the flood in 2006. Significant improvement in flood preparedness activities is still necessary. Particularly for businesses, regulatory programs and programs encouraging proactive behaviour should be implemented. The focusing event framework proofed to be a useful tool for a differentiated analysis of the responses to and learning due to a disaster also in the commercial and private sector. 相似文献
880.
Stakeholder engagement in social learning to resolve controversies over land-use change to plantation forestry 总被引:1,自引:1,他引:0
Rapid land-use change arising from incentives for afforestation has created tensions in rural communities previously dominated
by agricultural enterprises. This paper reports on an innovative experiment with social learning that incorporated participatory
modelling to resolve community concerns in a case study of plantation forestry in the Upper Clarence catchment of north-eastern
NSW Australia. The development of a diagnostic framework helped identify socioeconomic and environmental issues within the
community for investigation by a self-selected participatory advisory committee (PAC) representing a diversity of views. Implementation
of a social learning exercise offered empathetic and intellectual engagement among PAC members that maintained interest, built
confidence, and improved problem-solving capacity while fostering group ownership over decision making. A shared understanding
of dynamic landscape problems helped empower participants to collaboratively develop solutions for improved management and
operational practices, and cooperate to explore further options for plantation industry development under existing policy
guidelines which are presented in this paper. As a result of frank discussions between diverse stakeholders in a mutually
respectful learning environment that combined local, scientific and expert knowledge, concerns dissipated and participants
developed a more favourable view of plantation forestry activity. 相似文献