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741.
Climate change vulnerability is disproportionately distributed between different population segments in society. This study qualitatively explores how key stakeholders in municipalities (i.e. planning and operational staff in municipalities and the vulnerable themselves) construct social vulnerability in relation to climate change with a specific focus on thermal stress (i.e. heat waves) and which adaptive responses they identify at different levels. The empirical material consists of five focus groups with actors in a large Swedish municipality where the “Vulnerability Factor Card Game” was used as stimulus material to create 10 fictional individuals. The results show that there is a substantial amount of local knowledge about vulnerability drivers and inter-relations between social factors and vulnerability. Local decision-makers also defined a wide range of possible adaptation measures at different municipal levels. Our study clearly indicates that contextualised knowledge, which could complement the quantitative approaches in research, is abundant among municipal planners, staff employed at municipal operations such as health care, and among the vulnerable themselves. This knowledge remains untapped by research to a great extent and only seems to have an insignificant influence on policy-making. In particular, how impacts vary between different social and demographic groups and how adaptation strategies that target the most vulnerable could be defined are of great interest. The present study clearly indicates that social hierarchy may produce increased inequality in the specific context of climate change, vulnerability and adaptive responses at different levels.  相似文献   
742.
Climate change presents a complex environmental health and justice challenge for the field of urban planning. To date, the majority of research focuses on measuring local climate efforts and evaluating the general efficacy of adopted climate action plans (CAPs). Cumulatively, these studies argue that socio-economic and demographic variables (such as the fiscal health of cities, city size, and median household income) are important factors in implementing climate policies. Less studied are issues of environmental justice and the impacts of climate change on population health. Through interviews with urban planners and a document analysis of CAPs, this study assesses how California cities with high levels of pollution and social vulnerability address climate change and public health. The findings of this study show that CAPs in these cities rarely analyse whether greenhouse gas reduction strategies will also yield health co-benefits, such as a reduction in the co-pollutants of climate change (i.e. ozone, particulate matter, and nitrogen oxides). In many instances, the net co-benefits of health are not monetised, quantified, or even identified by local governments. In California's most impacted cities, climate planning activities and work on public health are happening in a parallel manner rather than through an integrated approach. The results suggest a need for increased opportunities for interagency coordination and staff training to conduct health analyses, free and easily accessible tools, methods for prioritising funding streams, and the development of partnerships with community-based organisations for linking climate planning with public health.  相似文献   
743.
Since the inception of sustainable development (SD), there has been a somewhat ignored contradiction between paradigms that are ecosystem‐based and paradigms that are human‐based or purely economic. We suggest that this contradiction can be unified through a balance of the two. The Chinese Yin‐Yang philosophy is applied as a tool or approach to seeking balance between these ecocentric and anthropocentric paradigms. Priority education policy design for the merging of ecology and health are projected through an Ecohealth lens in response to increasing SD challenges and the intention of the international Ecohealth organization to contribute to SD goals. Meeting SD goals along the nexus of health and environment is further considered through early‐careerist cultural assessments and projections. The groups considered for their professional image of the future are: members of the Ecohealth Association Student Section and Chinese early‐careerists participating in a related conference. In response to SD goals, a problem‐based learning design is suggested as an education policy priority. Rather than approaching SD as a boolean concept, for example, by either focusing on ecosystem sustainability or economic development, we suggest education policy for programmes and curriculums that will help emerging professionals balance these paradigms, so as to best address national and global challenges.  相似文献   
744.
Assisted colonization of vascular plants is considered by many ecologists an important tool to preserve biodiversity threatened by climate change. I argue that assisted colonization may have negative consequences in arctic‐alpine and boreal regions. The observed slow movement of plants toward the north has been an argument for assisted colonization. However, these range shifts may be slow because for many plants microclimatic warming (ignored by advocates of assisted colonization) has been smaller than macroclimatic warming. Arctic‐alpine and boreal plants may have limited possibilities to disperse farther north or to higher elevations. I suggest that arctic‐alpine species are more likely to be driven to extinction because of competitive exclusion by southern species than by increasing temperatures. If so, the future existence of arctic‐alpine and boreal flora may depend on delaying or preventing the migration of plants toward the north to allow northern species to evolve to survive in a warmer climate. In the arctic‐alpine region, preventing the dispersal of trees and shrubs may be the most important method to mitigate the negative effects of climate change. The purported conservation benefits of assisted colonization should not be used to promote the migration of invasive species by forestry.  相似文献   
745.
Changes in land use and land cover are important in global climate change, but the many uncertainties in historical estimates seriously hamper climate modelling. We collected new data on estimated per capita land use over the last two millennia, using new data sources from the Humanities. In general, and in agreement with literature, we found that per capita land use indeed has not been constant in the past, but differ per region and over time. Land use in the distant past was mostly less than 1 ha/cap. However, the recently colonised regions show much higher values and have experienced a much higher per capita land use for the recent past. Most known trajectories follow a concave or bell-shaped curve towards the present.  相似文献   
746.
Cyanobacterial bloom events in South Taihu Lake cause serious water quality problems and disturb aesthetic view of lake’s environment. In this study, correlations between cyanobacterial blooms and hydro-meteorological factors, including water quality, temperature and precipitation were investigated. Results demonstrated that South Taihu Lake was heavily affected by cyanobacteria and the proliferation of cyanobacteria due to variations in hydro-meteorological factors and water quality conditions. Water quality parameters, including COD, NH3-N, TN and TP improved significantly since 2008 even at an elevated cyanobacterial bloom situation. Correlation analyses have shown that the development of cyanobacterial density and chlorophyll a concentration was sensitive to a wider temperature variation. The optimum temperature for cyanobacteria was 20°C, while extremely low and high temperatures were found to suppress their growth. Moreover, unusual rainfall patterns were measured during the study period (2003–2009), which showed an adverse impact on cyanobacterial development. Findings from this study suggested that seasonal lake’s water quality monitoring; suitable treatment of cyanobacterial blooms and strict policy implementation can solve the water quality issues in highly eutrophic lakes like Taihu.  相似文献   
747.
In late 1995, school children discovered malformedfrogs in a south central Minnesota pond. Press coverage resultedin numerous citizen reports of frog malformation across Minnesotain 1996. After some initial site investigation, 3 affected frogsites and 4 nearby reference sites were selected for moredetailed evaluation. Field biologists made 89 visits to studysites beginning spring 1997 through fall 1999 to examine thenumber and type of frog malformations. Over 5,100 Leopardfrogs (Rana pipiens) were captured and examined atall study sites. Water elevations and associated littoralinundation were recorded from 1997-2000. Results indicate thatmalformation occurred at all study sites above historicalbackground levels. Rana pipiens malformation across allsites over three seasons averaged 7.9% and ranged from 0 to 7% at reference sites and 4 to 23% at affected sites. At onenorthern Minnesota site, mink frog (Ranaseptentrionalis) malformation was 75% in 1998. A sitecharacteristic common to the most affected sites was an elasticzone of littoral inundation. Climate driven hydrologic variationlikely influenced water depth and associated breeding locations.  相似文献   
748.
What impact does ecological uncertainty have on agents' decisions concerning domestic emissions abatement, physical investments, and R&;D expenditures? How sensitive are the answers to these questions when we move from exogenous to endogenous technical change? To investigate these issues we modify the ETC-RICE model described in Buonanno et al. (2001) by embedding in it a hazard rate function as in Bosello and Moretto (1999). With this model at hand we run numerical optimisations focusing our attention on the control variables of the representative agents, i.e., domestic abatement rate, investments in physical capital, and R&;D spending, as well as on the endogenous patterns of GDP level and CO2 emissions. Our results show that uncertainty strongly influences agents behaviour; in particular, agents slow down their emissions in order to maintain a more sustainable growth path. In addition, R&;D expenditures trigger the “engine of growth” exclusively when environmental technical change is formalized in an endogenous fashion. However, even if environmental uncertainty may stimulate technical change, long-run growth it turns out to be negatively affected by the former, as also predicted by Clarke and Reed (1994) Tsur and Zemel (1996) and Bosello and Moretto (1999).  相似文献   
749.
The Kyoto Protocol created the Clean Development Mechanism (CDM) to allow industrial countries to reach part of their greenhouse gas (GHG) emission reduction through projects in developing countries. To calculate the achieved emission reduction a reference scenario has to be developed – the baseline. Despite efforts to develop realistic baselines, a certain degree of uncertainty regarding actual reductions will be inevitable. It is therefore necessary to compare the costs (including transaction costs) of developing a baseline against the informational benefit it can be expected to produce. While project-related baselines are already being applied, the proponents of country-related baselines have still to show the applicability of their approach for the CDM. The possibility of quantifying indirect effects and considering market distortions and subsidies through aggregation in the country-related baselines is weighed up by the manipulability and uncertainty of the assumptions required in such a baseline. Thus project-specific baselines are recommended. In cases of severely distorted markets undergoing liberalization or subsidy phase-out, a country-related baseline can be helpful. Sectoral or programme baselines would be suited to large-scale energy and sequestration projects. Moreover it has to be considered whether emission reductions are generally achieved in the context of relocation or done in the context of global emitting capacity expansion.  相似文献   
750.
Few studies on measures for mitigation of damage caused by man-made emissions to the environment have tried to consider all major effects. We illustrate the importance of an integrated approach by estimating costs and benefits of a proposed energy saving program for Hungary, originally designed to reduce CO2 emissions. The dominant benefit of implementing the program is likely to be reduced health damage from local pollutants. Also reduced costs of material damage and to a lesser extent vegetation damage contribute to make the net benefit considerable. Compared to the reduction in these local and regional effects, the benefits from reducing greenhouse gases are likely to be minor. Since local effects in general occur much earlier after measures have been implemented than effects of increased emissions of greenhouse gases, inclusion of local effects makes evaluation of climate policy less dependent on the choice of discount rate. In our opinion, similar results are likely for many measures originally designed to reduce emissions of greenhouse gases particularly in some areas in developing countries with high local pollution levels. Main uncertainties in the analysis, e.g. in the relationships between damage and pollution level, are discussed.  相似文献   
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