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71.
Quantification of the Impact of Land-Use Changes on Ecosystem Services: A Case Study in Pingbian County, China 总被引:3,自引:0,他引:3
Li RQ Dong M Cui JY Zhang LL Cui QG He WM 《Environmental monitoring and assessment》2007,128(1-3):503-510
Pingbian Miao Autonomous County is one of the poorest rural areas in China. Land-use changes, mainly driven by agricultural
expansion and deforestation, may significantly impact ecosystem services and functions, but such effects are difficult to
quantify. In the present study, Landsat image data were combined with the published coefficients about the world and China
ecosystem to quantify land-use and ecosystem service changes in the mountainous area. A sensitivity analysis was employed
to determine the effect of manipulating these coefficients on the estimated values. Our results show that during the past
decades (from 1973 to 2004) forests and grasslands were converted into shrubland and cropland, respectively, resulting in
a continuous decrease in ecosystem service (from 124.5 US$ × 106 in 1973 to 100.4 US$ × 106 in 2004). We found that the decrease of mixed forest in the study area was the largest contributor (i.e., 25.4 US$ × 106) to the decline of the ecosystem service. Therefore we propose that future land-use policy should pay more attention to the
crucial ecosystem functions of these forests (including tropical forest), and that it is necessary to balance the relationship
between the livelihood of local farmers and environmental protection in order to maintain a healthy and stable ecosystem. 相似文献
72.
Benefit distribution plays a central role in incentivizing action in REDD+ (Reducing Emissions from Deforestation and Degradation and forest enhancement). Conceived as a global performance-based incentive mechanism to reduce land-use emissions in developing countries, REDD+ involves changes in resource governance by many actors at multiple scales, in order to minimize the climate impact of land-use activities or to maximize their contribution to reducing greenhouse gas emissions. A key governance issue for developing countries is how to incentivize action among stakeholders and the way countries design their benefit-sharing mechanisms (BSMs) is therefore seen as a critical factor in determining the success of REDD+ in the long term. This comprehensive research investigates up-to-date national level REDD+ planning documents to provide new evidence on how countries are planning to implement BSMs, including an analysis of common governance themes and where gaps exist. Our unique comparative study based on five country cases reveals that there is a lack of comprehensive participatory, transparent and accountable processes among country strategies and in particular, shortcomings in preparation for local and subnational governance, financial disbursement and dispute-resolution mechanisms. Furthermore, countries are making slow progress on land tenure and carbon rights reform. In fact, such ambiguous legislation on carbon benefits, coupled with weak institutional capacity and ineffective dispute-resolution mechanisms, may make it difficult for REDD+ stakeholders to participate fully in initiatives and receive a fair distribution of benefits. This research indicates that REDD+ actors including donors and national governments will need to further rethink strategies and policy frameworks to improve their BSMs and to guarantee effective, equitable and efficient REDD+ outcomes in the long term. 相似文献
73.
This study describes the deforestation impact from three settlements, 5 de Junio, El Tigre, and 30 de Agosto, near the Madidi National Park in Bolivia. First deforestation rates along the road that connects the settlements and then deforestation within each settlement are examined. Landsat Thematic Mapper (TM) imagery from 1987, 1997, and 2000 were used to measure the deforestation. Face-to-face interviews were also used to collect detailed social and land-use information. Road-building and farming have been the major causes of deforestation in this region. The TM measurements indicate a high increase in the deforestation rate along the road in the area of study. The results also show a rapidly escalating deforestation rate in 5 de Junio, a potential high future deforestation rate in El Tigre, and a gradual deforestation increase in 30 de Agosto. The information provided by the settlers about clearing was compared with the imagery analysis. Generally, the settlers estimates were lower than the deforestation as derived from the imagery. 相似文献
74.
This study aimed at clarifying the impact of deforestation and afforestation on the quality of life in a village in Sichuan Province, China. We devised a conceptual model of bioresource production and use based on quantified energy flow. The basic structure of the model has three sectors: production, use, and externals. We developed comprehensive methodology to quantify the model. Bioresource use per person in 1997 was 3.7 GJ for food, 10.2 GJ for fodder, 0.2–0.4 GJ for building material, 12.8 GJ for fuel, and 1.8 GJ for fertilizer, totaling 28.6–28.8 GJ.We used four environmental indicators to evaluate bioresource production and use: a biological productivity indicator, a use-efficiency indicator, a supply–demand balance indicator, and a self-sufficiency indicator. Use of these indicators showed that supply-demand balance of fuel was dramatically improved from 30% to 85% by afforestation, but 99% of bioresource use still depends on domestic products. Thus, it is necessary to improve biological productivity and promote the efficient use of bioresources to achieve sustainable living in the area. Massive deforestation in the 1950s caused a direct shortage of building material and fuel wood. The shortage of wood led to a stagnation in the rebuilding of houses, and fuel wood was substituted with crop residues. Because crop residues had been used for fertilizer and fodder, their use as fuel caused a shortage of fertilizer and fodder. This was an indirect impact of deforestation on peoples quality of life. 相似文献
75.
The Central Himalayan region is suffering from severe ecological problems as a consequence of deforestation and that threatens
the subsistence population of the region. We analyze this problem and propose a plan for ecologically sustainable development
for the region based on an analysis of the interrelationships of various ecosystems, particularly cropland and forest ecosystems,
around which most human activities are concentrated. Each energy unit of agronomic yield leads to expenditure of about 12
energy units of forest/grazing land energy. Because with rapidly declining forest area, this form of agriculture is no longer
sustainable and cannot be converted into a fossil fuel-based agriculture, we propose that agriculture in the mountain region
has to be largely replaced with farm forests to revitalize the environment and to generate the basic needs of the subsistence
economy of the hill population whose food grain needs can be met from the plains. We conclude by describing the advantages
that are likely to accrue to the people for their long-term future. In terms of both energy and money, the value of resources
collected from the forest to support agriculture in the present systems far exceeds the value of food grain that would be
required to enable the proposed farm forest-based systems to function. At regional level, the proposed system would generate
more energy than the existing systems, not only because the productivity of forest is about tenfold greater than that of cropland,
but also because the proposed plan promotes recovery of various ecosystems. 相似文献
76.
Philip M. Fearnside 《Mitigation and Adaptation Strategies for Global Change》2009,14(6):557-567
Amazonian forest reserves have significant carbon benefits, but the methodology used for accounting for these benefits will
be critical in determining whether the powerful economic force represented by mitigation efforts to slow global warming will
be applied to creating these reserves. Opportunities for reserve creation are quickly being lost as new areas are opened to
deforestation though highway construction and other developments. Leakage, or the effects that a reserve or other mitigation
project provokes outside of the project boundaries, is critical to a proper accounting of net carbon benefits. Protected areas
in the Amazon have particularly great potential mitigation benefits over an extended time horizon. Over a 100-year time frame,
virtually no unprotected forest is likely to remain, meaning that potential leakages (both leakage to the vicinity of the
reserves and that displaced by removing protected areas from the land-grabbing market) should not matter much because any
short-term leakage would be “recovered” eventually. The effect of the value attributed to time greatly influences the impact
of leakage on benefits credited to reserves. Simple assumptions regarding leakage scenarios illustrate the benefits of reserves
and the critical areas where agreement is necessary to make this option a practical component of mitigation efforts. The stakes
are too high to allow further delays in reaching agreement on these issues. 相似文献
77.
Brazil’s Cuiabá- Santarém (BR-163) Highway: The Environmental Cost of Paving a Soybean Corridor Through the Amazon 总被引:1,自引:0,他引:1
Fearnside PM 《Environmental management》2007,39(5):601-614
Brazil’s Cuiabá-Santarém (BR-163) Highway provides a valuable example of ways in which decision-making procedures for infrastructure
projects in tropical forest areas need to be reformulated in order to guarantee that environmental concerns are properly weighed.
BR-163, which is slated to be paved as an export corridor for soybeans via the Amazon River, traverses an area that is largely
outside of Brazilian government control. A climate of generalized lawlessness and impunity prevails, and matters related to
environment and to land tenure are especially unregulated. Deforestation and illegal logging have accelerated in anticipation
of highway paving. Paving would further speed forest loss in the area, as well as stimulate migration of land thieves (grileiros) to other frontiers. An argument is made that the highway should not be reconstructed and paved until after a state of law
has been established and it has been independently certified that sufficient governance prevails to secure protected areas
and enforce environmental legislation. A waiting period is needed after this is achieved before proceeding with the highway
paving. Above all, the logical sequence of steps must be followed, whereby environmental costs are assessed, reported, and
weighed prior to making de facto decisions on implementation of infrastructure projects. Deviation from this logical sequence is a common occurrence in many
parts of the world, especially in tropical areas. 相似文献