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481.
Genesis T. Yengoh Augustin Tchuinte Frederick Ato Armah Justice O. Odoi 《Mitigation and Adaptation Strategies for Global Change》2010,15(8):825-841
This study set out to examine why agricultural production in differing agro-ecological zones of the same country responds
differently to a common environmental event (an extension of the rainy season). We find that the heavy reliance of farmers
in the drier agro-ecological zones on seasonal cycles make them more vulnerable to an extension of the rainy season than those
in regions where rainfall is less relied on. Effects in these vulnerable regions include significant damage to crops as well
as a shortage in local markets, which raises prices of basic food commodities. The difference between prices in low and high
food producing periods is low for crops that can easily be preserved during rains (such as cassava at 58% from an average
of 20% in previous years and yams at 82% from 65%). Crops that depend on sunshine for preservation experience greater differences
between low and high periods (maize at 92% from an average of 31% in previous years, sorghum at 180% from 53%, and beans at
68% from 42%). In zones with a history of unreliable dry seasons, farmers are more adapted to coping with an extension of
the rainy season and possess technology and skills which can be made available to others in vulnerable zones through inter-regional
knowledge transfer of knowledge and skills. This study further reinforces the understanding that isolated climate shocks could
be important in understanding and managing vulnerability. Also, vulnerability is quite variable even among communities in
the same country, in which people practice the same economic activity and are exposed to the same shock. 相似文献
482.
Andrea Cattaneo Ruben Lubowski Jonah Busch Anna Creed Bernardo Strassburg Frederick Boltz Ralph Ashton 《Environmental Science & Policy》2010,13(8):742-753
Reducing emissions from deforestation and forest degradation (REDD) can be an effective and efficient means of mitigating climate change. However, the perceived equity in the distribution of financial incentives for REDD could also emerge as a critical issue in international negotiations. The design of reference levels, which provide the benchmark for crediting emissions reductions, affects the economic incentives for national participation in a REDD mechanism and thus the overall willingness to reach an agreement on REDD. This paper compares the equity impacts of five proposed reference level designs using a partial-equilibrium model. Tradeoffs among equity, environmental effectiveness and cost-efficiency indicate the proposals trigger similar aggregate emissions reductions but lead to different outcomes in efficiency and alternative measures of equity. If equity across countries is measured as the financial incentive provided relative to a country's forest carbon stock, then a REDD mechanism compensating a uniform share of at-risk carbon stocks is the most equitable. On the other hand, if equity is evaluated as the financial incentive relative to the opportunity costs of participating in REDD, then the most equitable approach would be compensating emissions reductions but withholding a part of the payments to compensate for carbon stocks, which also encourages broader country participation under our model. 相似文献
483.
Frederick A. Armah Justice O. Odoi Genesis T. Yengoh Samuel Obiri David O. Yawson Ernest K. A. Afrifa 《Mitigation and Adaptation Strategies for Global Change》2011,16(3):291-306
Desertification, climate variability and food security are closely linked through drought, land cover changes, and climate
and biological feedbacks. In Ghana, only few studies have documented these linkages. To establish this link the study provides
historical and predicted climatic changes for two drought sensitive agro-ecological zones in Ghana and further determines
how these changes have influenced crop production within the two zones. This objective was attained via Markov chain and Fuzzy
modelling. Results from the Markov chain model point to the fact that the Guinea savanna agro-ecological zone has experienced
delayed rains from 1960 to 2008 while the Sudan savanna agro-ecological zone had slightly earlier rains for the same period.
Results of Fuzzy Modelling indicate that very suitable and moderately suitable croplands for millet and sorghum production
are evenly distributed within the two agro-ecological zones. For Ghana to adapt to climate change and thereby achieve food
security, it is important to pursue strategies such as expansion of irrigated agricultural areas, improvement of crop water
productivity in rain-fed agriculture, crop improvement and specialisation, and improvement in indigenous technology. It is
also important to encourage farmers in the Sudan and Guinea Savanna zones to focus on the production of cereals and legumes
(e.g. sorghum, millet and soybeans) as the edaphic and climatic factors favour these crops and will give the farmers a competitive
advantage. It may be necessary to consider the development of the study area as the main production and supply source of selected
cereals and legumes for the entire country in order to free lands in other regions for the production of crops highly suitable
for those regions on the basis of their edaphic and climatic conditions. 相似文献