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301.
Abstract The aim of this paper is to use Erikson's approach to human development, and specifically generativity, as a framework by which to explore older people's experiences of environmental stewardship activities. Using data from a large qualitative study of environmental volunteers resident in the coastal fringes of Queensland, Australia, the paper provides important, illustrative, empirical support for Erikson's theory of generativity in later life. Findings suggest that older people are much more likely to connect their environmental actions with the longer-term future, and express a need to leave a lasting legacy for future generations. According to respondents, the later years are a time to contribute to the environment as part of a broader cycle of life. The environment is also an important site for intergenerational activities. Whilst the work presented here is only a small, localized study, use of Erikson's theory of human development as a framework helps demonstrate the importance of a generative response in later life. 相似文献
302.
Many voluntary incentive programs for provision of forest ecosystem services (ES) have low participation rates, insufficient enrollment areas, and inefficient ecological outcomes. Understanding participation behavior in such programs has therefore become a crucial part of policy success. We synthesized a large body of literature on the behavior of nonindustrial private forest owners based on surveys of stated (intended) participation or data on actual participation in existing or hypothetical programs. Using metaregression analysis, we examined how methodological, program-characteristic, and economic-incentive variables affected participation rate estimates. Participation rates tended to be overestimated when landowner participation was elicited in hypothetical choice situations (compared with real situations) and when dichotomous choice surveys (compared with census data) were used. The marginal effect sizes were quite large, for example, a 31% increase with use of stated choices in hypothetical scenarios, and practitioners should therefore be aware of them. However, use of choice experiment surveys in a modified scenario based on existing programs had no effect on participation when all other determinants were controlled for. Participation rates decreased significantly as length of the contract increased and when there was no withdrawal option. These results suggest that perpetual contracts have a lower negative impact on participation than time-limited contracts with a duration of over 50 years. We confirmed that as compensation amounts increased, participation increased. One-time up-front payments were more effective in increasing initial participation than annual payments for contracts of over 5 years. We identified the robust determinants and the effect sizes of those determinants on landowner participation rate estimates, thereby contributing to a better understanding of forest owner behavior and offering useful insights to enable researchers and resource managers to improve the design and efficiency of new and existing forest ES programs. 相似文献
303.
304.
Athanasios Ragkos Asimakis Psychoudakis Argiro Christofi Alexandros Theodoridis 《Regional Environmental Change》2006,6(4):193-200
This study proposes the valuation of wetland functions as an alternative to the conventional approach to wetland valuation, in order to derive indicators for decision-making in wetland management. It is illustrated that these functions can be valuated in terms of the goods and services they provide to society. Using a functional approach, the functions are identified and the goods and services they provide are explicitly allocated among them; then, the latter are valuated with the Contingent Valuation method. Statistical analysis of the data provides welfare measures that reflect the value of these functions. It is argued that the values of separate functions are more useful in policy-making than their aggregated value.
相似文献
Athanasios RagkosEmail: Phone: +30-2310-998826Fax: +30-2310-998828 |
305.
Ferng JJ 《Environmental management》2007,40(6):913-925
Freshwater is necessary to economic activity, and humans depend on goods and services generated by water-dependent ecosystems.
However, national freshwater management usually focuses on direct use of domestic freshwater. With an increasing scarcity
of freshwater, attention has turned to two indirect uses of freshwater by humans. The first indirect use is freshwater used
by foreign countries when producing products for export. The second use is freshwater required by local ecosystems: human
survival and development depend on goods and services generated in these ecosystems. This work adopted Taiwan as a case study.
In addition to two widely recognized ecosystem freshwater demands, evapotranspiration and reversed river flow, this study
suggests that freshwater is a constituent of some abiotic components, such as groundwater in aquifers, because excessive withdrawal
has already caused significant land subsidence in Taiwan. Moreover, the estimated results show that Taiwan’s net imports of
freshwater through trade amounts to approximately 25% of its total freshwater use for economic production. Integrating industrial
policy, trade policy, and national freshwater management is a useful approach for developing strategies to limit the growing
use of freshwater in Taiwan. Policy implications are then developed by further analyzing withdrawal sources of freshwater
(domestic and foreign) for supporting economic production in Taiwan and identifying the factors (domestic final demand and
export) driving freshwater-intensive products. 相似文献
306.
Ecosystem services provided by the landscapes of regions and cities are critical to human and environmental health, quality of life, environmental justice, biodiversity and climate mitigation and adaptation. In the Pacific Northwest region of the US, a team led by the University of Washington Green Futures Lab is working to identify, conserve and enhance regionally-significant landscapes and to evaluate their contributions as ecosystem or “open space” services. This paper outlines the goals and planning methods of the ongoing Regional Open Space Strategy for Central Puget Sound (ROSS) project, and the frameworks and processes being developed to evaluate ecosystem and open space services in order to inform and influence local and regional governance structures and decisions. 相似文献
307.
基于生产可能性边界的黄河三角洲湿地生态系统服务权衡强度 总被引:3,自引:0,他引:3
提出了一种基于生产可能性边界(PPF)的湿地生态系统服务权衡强度计算方法,包括湿地生态系统服务定量评估、权衡关系判定、PPF曲线绘制和权衡强度计算四个步骤。以黄河三角洲湿地为研究对象,对保护情景、现状发展情景及开发情景三种土地利用发展模式下的主导生态系统服务进行了定量化权衡分析。结果表明:各生态系统服务间呈现显著相关关系(R2≥0.9,P<0.01),各发展情景下,栖息地质量与碳储量之间均为协同关系;物质生产与栖息地质量间均为权衡关系,排序为保护情景<基期<现状发展情景<开发情景;而对于物质生产与碳储量之间,在保护及现状发展情景下存在协同关系;而开发情景下转变为权衡关系。该模型通过灵活比较不同生态服务间权衡关系分析进行系列管理规划的方案优选,为实现区域可持续发展提供科学依据。 相似文献
308.
Toledo-Aceves T Meave JA González-Espinosa M Ramírez-Marcial N 《Journal of environmental management》2011,92(3):974-981
Tropical montane cloud forests (TMCF) are among the most threatened ecosystems globally in spite of their high strategic value for sustainable development due to the key role played by these forests in hydrological cycle maintenance and as reservoirs of endemic biodiversity. Resources for effective conservation and management programs are rarely sufficient, and criteria must be applied to prioritize TMCF for conservation action. This paper reports a priority analysis of the 13 main regions of TMCF distribution in Mexico, based on four criteria: (1) forest quality, (2) threats to forest permanence, (3) threats to forest integrity, and (4) opportunities for conservation. Due to the diverse socio-environmental conditions of the local communities living in Mexican TMCF regions, their associated social characteristics were also evaluated to provide a background for the planning of conservation actions. A set of indicators was defined for the measurement of each criterion. To assign priority values for subregions within each main region, an international team of 40 participants evaluated all the indicators using multicriteria decision-making analysis. This procedure enabled the identification of 15 subregions of critical priority, 17 of high priority, and 10 of medium priority; three more were not analysed due to lack of information. The evaluation revealed a number of subjects that had hitherto been undetected and that may prove useful for prioritization efforts in other regions where TMCF is similarly documented and faces equally severe threats. Based on this analysis, key recommendations are outlined to advance conservation objectives in those TMCF areas that are subjected to high pressure on forest resources. 相似文献
309.
A generic input-state-output scheme has been used to represent ecosystem dynamics. Systemic approaches to ecosystems use functions that are based either on inputs, state or outputs of the system. Some examples of approaches that use a combination of functions have been recently proposed. For example the use of eco-exergy to emergy flow can be seen as a mixed input-state approach; more recently, to connect the state to the output of the ecosystem, the relation of eco-exergy and ecosystems services has been proposed. This paper studies the link between the useful output of an ecosystems and its input through the relation between ecosystem services and emergy flow, in a kind of grey/black box scheme (i.e., without considering the state and the structure of the ecosystem). No direct connection between the two concepts can be determined, but identifying and quantifying the emergy flows feeding an ecosystem and the services to humans coming from them facilitate the sustainable conservation of Nature and its functions. Furthermore, this input-output relation can be established in general by calculating the ratio of the value of the ecosystem services to the emergy flow that supports the system. In particular, the ratio of the world ecosystem services to the emergy flow supporting the entire biosphere has been calculated showing that, at least at the global level, Nature is more efficacious in producing “money” (in form of ecosystem services) than economic systems (e.g., national economies and their GDP). 相似文献
310.
VALUING ECOSYSTEM SERVICES OF CHILEAN TEMPERATE RAINFORESTS 总被引:1,自引:0,他引:1
LAURA NAHUELHUAL PABLO DONOSO ANTONIO LARA DAISY NÚÑEZ CARLOS OYARZÚN EDUARDO NEIRA 《Environment, Development and Sustainability》2007,9(4):481-499
The Valdivian Rainforest Ecoregion (35°–48° S) in southern South America is among the ecosystems with highest conservation
priority worldwide due to its rich diversity, degree of endemism, and critical conservation status. Temperate rainforests
in this vast area are essential as source of biological resources and to maintain different ecosystem services which remain
largely unmeasured and unvalued. Consequently, the benefits they provide are not reflected in decision-making regarding forest
management and conservation. Based on existing studies and results from ongoing research we describe selected ecosystem services
and provide estimates of their economic value. Timber benefits for secondary forests expressed as net present stumpage values
were US$ 3742 ha−1 and US$ 3093 ha−1 for sustainable forest management (SFM) and unsustainable harvesting, respectively. Timber benefits for old growth forests␣equaled
US$ 4546 ha−1 and US$ 5718 ha−1, for SFM and unsustainable harvesting, respectively, using an 8% discount rate. Annual benefits from recreation were US$
1.6 ha−1 and US$ 6.3 ha−1 for the two most important national parks located in the study area. The annual value of maintaining soil fertility was US$
26.3 ha−1 using the replacement cost of nutrient losses due to soil erosion. The annual economic value of water supply for human consumption
using the production function method was US$ 235 ha−1. These results provide valuable information on the kind and magnitude of values that could be relevant in decision-making
concerning conservation and management of native forests in the Valdivian Rainforest Ecoregion. 相似文献