全文获取类型
收费全文 | 124篇 |
免费 | 14篇 |
国内免费 | 17篇 |
专业分类
安全科学 | 6篇 |
环保管理 | 24篇 |
综合类 | 24篇 |
基础理论 | 68篇 |
污染及防治 | 4篇 |
评价与监测 | 8篇 |
社会与环境 | 14篇 |
灾害及防治 | 7篇 |
出版年
2023年 | 3篇 |
2022年 | 1篇 |
2021年 | 3篇 |
2020年 | 5篇 |
2019年 | 4篇 |
2018年 | 6篇 |
2017年 | 5篇 |
2016年 | 4篇 |
2015年 | 11篇 |
2014年 | 4篇 |
2013年 | 20篇 |
2012年 | 3篇 |
2011年 | 6篇 |
2010年 | 7篇 |
2009年 | 4篇 |
2008年 | 2篇 |
2007年 | 10篇 |
2006年 | 7篇 |
2005年 | 17篇 |
2004年 | 10篇 |
2003年 | 5篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1992年 | 2篇 |
排序方式: 共有155条查询结果,搜索用时 31 毫秒
101.
Alpina Begossi Fernando Dias de Ávila-pires 《Environment, Development and Sustainability》2003,5(1-2):179-195
Latin America comprehends notable variations in terms of natural environment, availability of natural resources, living standards, and demographic patterns. Latin America is a mosaic of cultures, post- and pre-Columbian. The rich variety of life forms discovered and described by chroniclers and traveling naturalists in the Neotropics contributed to the proposal, in mid-XVIIIth century, of a new system of classification and a scientific code of nomenclature for all organisms. Biodiversity was, for many centuries, a source of resources to be exploited in natura. In scientific circles, its inventory became the domain of taxonomists. But modern technology showed how important the miriad of life forms really are as sources of chemical molecules to be engineered as drugs and reassembled as novel manufactured products. We are on the brink of a new agricultural and medical revolution, thanks to the techniques of genetic engineering, which will lead eventually to the elimination of hunger and malnutrition.In this essay, the Brazilian environmental and social heterogeneity will serve as an example to illustrate some key points, which have influenced sustainability policies. The Amazon deforestation and indigenous knowledge (IK), subjects often associated with areas of high biodiversity, are usually the focus of environmental debates. The importance of IK in integrating development, reducing poverty and sustainability are considered together with the intellectual property rights of native populations.In the World Summit on Sustainable Development (WSSD) Implementation Plan, a few paragraphs were dedicated to Latin America, because of the pre-existing Action Platform on the Road to Johannesburg 2002, approved in Rio de Janeiro in October 2001. This paper calls attention to the need to draw up specific environmental policies for a region which shows an extremely high cultural and biological diversity, associated with a high availability of forests and water, among other resources. 相似文献
102.
Ranjay K. Singh Ramesh C. Srivastava Chandra B. Pandey Anshuman Singh 《Journal of Environmental Planning and Management》2015,58(1):69-90
This study reports on the biocultural dimensions of the tasat (Arenga obtusifolia Griff.) tree and its conservation by various informal institutions of the Adi tribe of Arunachal Pradesh, India. The study included 240 Adi community members (120 men and 120 women) residing in 12 villages of the East Siang and Upper Siang districts of Arunachal Pradesh. The study was conducted using personal interviews and participatory methods. Results indicated that the stem of tasat is used as a traditional food during droughts and in preparing an ethnic beverage. Tasat is being conserved by the Adi tribe in various habitats. Plant populations of tasat were observed relatively higher in Upper Siang than the East Siang district. The study found differences in the status of biocultural knowledge between genders and different age groups. Kebang and reglep are two indigenous institutions of men and women, respectively, and play leading roles in sustaining tasat plants in various habitats. Women of the Upper Siang district still maintain a knowledge network for diffusing biocultural knowledge related to tasat, among others, through a barter system. Changing land use patterns in agriculture affects tasat conservation. The value addition for tasat based products, and rewarding women who conserve tasat, can enhance the sustainability of tasat based on biocultural knowledge and institutions. 相似文献
103.
Reuel M. Bennett Paul Rodrigo F. Cordero Gershon S. Bautista 《Chemistry and Ecology》2013,29(4):320-328
The reductive adsorption of hexavalent chromium (Cr6+) using six indigenous microorganisms isolated from contaminated soil and water samples was investigated. Quantification of Cr6+ reduction was determined using the 1,5-diphenylcarbazide method followed measuring the absorbance at OD540. Bacterial isolates identified as Klebsiella pneumoniae, Bacillus firmus and Mycobacterium sp. were capable of absorbing Cr6+ efficiently into their biomass, whereas the fungal isolates, Aspergillus flavus, Aspergillus sp. and A. niger were capable of transforming Cr6+ to Cr3+ relative to cell-wall-binding properties. Infrared spectral analysis of functional groups showed that ?OH, ?NH2 and C?O with conjugated ?NH were the binding groups responsible for adsorption of Cr6+ within the biomass of isolates. The data highlight the promising biotechnological application of these isolates in removing carcinogenic and mutagenic Cr6+ from contaminated ecosystems. 相似文献
104.
THOR HARALD RINGSBY‡ BERNT-ERIK SÆTHER HENRIK JENSEN STEINAR ENGEN† 《Conservation biology》2006,20(6):1761-1767
Abstract: In conservation ecology there is an urgent need for indicators that can be used to predict the risk of extinction of populations. Identifying extinction-prone populations has been difficult because few data sets on the demographic characteristics of the final stage to extinction are available and because of problems in separating out stochastic effects from changes in the expected dynamics. We documented the demographic changes that occurred during the period prior to extinction of a small island population of House Sparrows ( Passer domesticus ) after the end of permanent human settlement. A mark-recapture analysis revealed that this decline to extinction was mainly due to increased mortality after closure of the last farm that resulted in a negative long-term-specific growth rate. No change occurred in either the structural composition (breeding sex ratio and age distribution) of the population or in female recruitment. No male, however, recruits were produced on the island after the farm closure. Based on a simple, stochastic, density-dependent model we constructed a population prediction interval (PPI) to estimate the time to extinction. The 95% PPI slightly overestimated the time to extinction with large uncertainty in predictions, especially due to the influence of demographic stochasticity and parameter drift. Our results strongly emphasize the importance of access to data on temporal variation that can be used to parameterize simple population models that allow estimation of critical parameters for credible prediction of time to extinction. 相似文献
105.
Nathanael D. Wiseman 《Local Environment》2013,18(9):1024-1045
This article examines key socio-ecological interactions identified during a climate change vulnerability assessment in the Alinytjara Wilurara natural resources management (NRM) region of South Australia. The complex local socio-ecological interactions are highlighted to guide a response to the challenge of adapting to climate change within the region. Recognising several key desert drivers which perpetuate degraded socio-ecological systems, this article recommends that a range of strategies be employed simultaneously to enhance local environmental management in association with remote indigenous communities, including: linking people and NRM more closely; tracking funding but ensuring systems can withstand periods of limited financial support; developing cross-sectoral and cross-institutional links; empowering and engaging communities; communicating effectively; and actively supporting local and traditional environmental knowledge. Unless climate change adaptation responses within the region are conceptualised and enacted within the context of complex local socio-ecological systems, NRM will not improve and social vulnerability will increase. 相似文献
106.
Biodiversity Conservation and Resource Tenure Regimes: A Case Study from Northeast Cambodia 总被引:1,自引:0,他引:1
The management of tropical protected areas is a contentious issue in resource management and often leads to an unproductive polarization of viewpoints supporting either protectionist or sustainable development paradigms. This paper argues for a context-driven approach whereby effective management requires inputs from both paradigms in different situations. A key element of context is understanding long-practiced resource tenures and their ability to meet future conservation and livelihood goals. Different types of tenure arrangements are often required for different resources. This approach is illustrated by analysis of Virachey National Park in NE Cambodia. This park encompasses part of the ancestral territory of ethnic Brao people, who rely upon swidden agriculture, fish, terrestrial wildlife, and various nontimber forest products (NTFPs) for their livelihoods. These people have developed a mix of resource tenure regimes to promote sustainable use and to maximize local benefits. In the face of contemporary pressures, some of these traditional approaches are effective, while others are not. The paper suggests avenues for building on long-established management practices of the Brao to achieve park management goals while enhancing the welfare of the Brao people. A mix of private ownership, common property management, and central government involvement may be required to maximize benefits to local people and ensure long-term protection of biodiversity. 相似文献
107.
WANG Ren zhong 《环境科学学报(英文版)》2002,(1)
IntroductionTheintra andinter specificvariationsofplantpopulationshavebeenwelldocumentedformanyplantpopulations (Bassow ,1 997;Callaway ,1 994;Delph ,1 993;Ford ,1 981 ;Jones,1 999;Monson ,1 989;Pavone ,1 985;Vavre,1 997) .However,mostofthestudiesfocusedoninter specificvariationsinmal… 相似文献
108.
Manure odor, which results in the increasing complaints and lawsuits, has increased the tension among swine producers and surrounding residents. The effects of Lactobacillus plantarum and different rates of soluble carbohydrates additions to swine manure on odorous compounds, chemical compounds and indigenous flora were evaluated. Additions were calculated on dried manure weight basis. Variables monitored included ammonia (NH3), hydrogen sulfide (H2S), odor offensiveness, pH, ammonium nitrogen(NH4^+-N), volatile fatty acids (VFAs), urease and indigenous flora. The results indicated that the combination of L. plantarum and soluble carbohydrates dramatically reduced manure pH. Lower pH resulted in the reduction of NH3 volatilization (34.6%-92.4%, P〈0.01), the increases of H2S (P〈 0.05) and NH4^+-N (5.3%-17.5%, P〈0.05). In addition, L. plantarum and soluble carbohydrates additions significantly reduced odor offensiveness, those VFAs related to malodor indicators(valeric acids, 12.3%-47.7%, P〈 0.05; iso-valeric, 3.5%-23.8%) and the main microorganisms responsible for odor production, with the number of Eubacteria in swine manure reducing by 4.9%, 11.6%, 17.4%, 34.1% and 32.2% respectively. 相似文献
109.
Demographic Responses by Birds to Forest Fragmentation 总被引:1,自引:0,他引:1
Abstract: Despite intensive recent research on the effects of habitat loss and fragmentation on bird populations, our understanding of underlying demographic causes of population declines is limited. We reviewed avian demography in relation to habitat fragmentation. Then, through a meta-analysis, we compared specific demographic responses by forest birds to habitat fragmentation, providing a general perspective of factors that make some species and populations more vulnerable to fragmentation than others. We obtained data from the scientific literature on dispersal, survival, fecundity, and nesting success of birds. Birds were divided into subgroups on the basis of region, nest site, biogeographical history, and migration strategy. Species most sensitive to fragmentation were ground- or open-nesters nesting in shrubs or trees. Residents were equally sensitive to fragmentation in the Nearctic and Palearctic regions, but Nearctic migrants were more sensitive than Palearctic migrants. Old World species were less sensitive than New World species, which was predicted based on the history of forest fragmentation on these two continents. Pairing success was the variable most associated with fragmentation, suggesting an important role of dispersal. Fledgling number or condition, timing of nesting, and clutch size were not associated with sensitivity to fragmentation, suggesting that negative fragmentation effects on birds do not generally result from diminished food resources with increasing level of fragmentation. Future studies on demographic responses of birds to habitat fragmentation would be more effective if based on a combination of measures that can distinguish among the demographic mechanisms underlying population changes related to habitat fragmentation. 相似文献
110.
Clements A 《Environmental monitoring and assessment》2004,99(1-3):233-243
Desertification of shrub and grassland into pinyon-juniper woodland is occurring over much of the Colorado Plateau in the
southwestern United States. As trees invade, they out-compete shrubs and grasses, increasing erosion rates and reducing infiltration
of moisture into the soil. This has caused habitat problems for wildlife, and reduced forage for livestock. These impacts
also affect the human communities that rely on ranching and tourism related to hunting. Past land use and management practices
including heavy livestock grazing, fire suppression and introduction of exotic annual plants are believed to have led to current
conditions. The Montrose office of the Bureau of Land Management has implemented an ecosystem-based program to reverse the
desertification process on public land. The program is centered on detailed landscape objectives describing the desired vegetation
mosaic on 360 000 ha of public land. The objectives outline proportions of plant seral stages and arrays of patch sizes for
each planning unit. These objectives are based on priority management issues and the need to replicate a natural vegetation
mosaic. Where the existing mosaic does not meet objectives, mechanical vegetation treatments and prescribed fire are used
to create early and mid-seral patches on the ground. This restored vegetation pattern and type should be sustained over time
through a natural fire regime and improved livestock management. Because many uncertainties exist, an adaptive management
process is being used that allows mosaic objectives to be changed or processes modified where monitoring or scientific research
indicate a need. 相似文献