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981.
Sun Jin 《中国人口.资源与环境(英文版)》2013,11(1):57-60
Abstract While analyzing overall planning and coordinated development of urban-rural areas, this paper shows that overall planning for the development of urban-rural areas is a requirement for the best use of productive forces. It means the setting up of a policy mechanism for coordinated growth. Recognizing this, the government should set up a way to lead and manage a unified program to increase service and decrease controlling administration power, while safeguarding and fulfilling the farmers' ownership to the means of production. 相似文献
982.
Abstract: In light of limited conservation funding, global conservation initiatives are increasingly focused on regions of the planet that have been identified as valuable on the basis of their species diversity, the vulnerability of resident species to extinction, or the perceived pristine nature of their ecosystems. Regions that have been resilient to high rates of extinction have not yet been systematically considered in conservation efforts. We used published range maps for 392 vertebrate species to compare historical and current species ranges. We used the results of the comparison to identify regions of the globe in which no known vertebrate species has been extirpated in the past 200 years. In 17 regions, no detectable vertebrate extinctions occurred in the past 200 years. In 6 other regions, reintroductions of species restored the full historic complement of vertebrate species. The effects of humans on a landscape, as measured by the human‐footprint index, although useful, was not a singularly good predictor of faunal intactness because more than 20% of intact land area was in heavily affected areas (50% of Earth's land area), and several regions where humans have had very little effect did not have intact faunas. Only 22% of intact land area was within protected‐area networks. High‐latitude areas were particularly underrepresented; they made up 3 of the 4 least‐protected areas in our analyses. Our results indicate that although protected areas are in some cases associated with the prevention of extinctions, there are many regions in which human activity coexists with intact vertebrate assemblages. In addition, our new approach for assessing the value of global regions for conservation identifies several regions that are not represented in other prioritization metrics. 相似文献
983.
984.
Protected areas present a global heritage. Assessing conservation achievements in protected areas is of crucial importance with respect to the on-time delivery of international biodiversity conservation targets. However, monitoring data from publicly accessible databases for comparative studies of conservation achievements in the protected areas of the world are very scarce, if not non-existent. At first glance this is surprising because, with regards to protected areas, at least according to well established protected area management guidelines and widely accepted public mandates, a great deal of monitoring work and data gathering is to be conducted. This would imply that data on changes of biodiversity in protected areas could be expected to exist, and the constant progress in information technologies and Web tools engenders hope that some of it might even be available online for the global public. This review article presents the results of an extensive online search and review of existing monitoring data from freely accessible online databases for its use in an assessment of conservation achievements in a larger sample of protected areas. Results show two contrary sides to the status quo of accessible data from the World Wide Web for conservation science: data overkill and data scarcity with poor metadata provision. While ever more research is, in fact, based on open-access online data, such as extrapolations of species ranges used in conservation management and planning, it remains almost impossible to obtain a basic set of information for an assessment of conservation achievements within a larger number of protected areas. This awareness has triggered a detailed discussion about the discrepancies in sharing data at the level of protected areas; mismatching relationships between expected activities in protected areas and the capacity for delivering these requirements are certainly among the main challenges. In addition, the fear of data misuse potentially resulting in harm for nature, careers, and competencies still seems to be a critical barrier strictly controlling the willingness to share data. Various initiatives aimed at tackling technical and cultural obstacles are introduced and discussed to reach the goal of a modern resource management based on adaptive management using digital opportunities of the new millennium for a sustainable global village. 相似文献
985.
Fuzzy adaptive management of social and ecological carrying capacities for protected areas 总被引:1,自引:0,他引:1
Commonly used methods of evaluating the degree of consistency of protected area ecosystems with social and ecological carrying capacities are likely to result in decision errors. This occurs because such methods do not account for imprecision and uncertainty in inferring the degree of ecosystem consistency from an observed ecosystem indicator. This paper proposes a fuzzy adaptive management approach to determine whether a protected area ecosystem is consistent with ecological and social carrying capacities and, if not, to identify management actions that are most likely to achieve consistency when there is uncertainty about the current degree of consistency and how alternative management actions are likely to influence that consistency. The proposed approach is illustrated using a hypothetical example that uses an ecosystem indicator that reflects combinations of different levels of user satisfaction and conservation of threatened and endangered species. Application of the proposed fuzzy adaptive management approach requires a protected area manager to: (1) identify alternative management actions for achieving ecosystem consistency with social and ecological carrying capacities in each of several management zones in a protected area; (2) randomly assign alternative management actions to management zones; (3) define fuzzy sets for the ecosystem indicator and degree of ecosystem consistency, and fuzzy relations between the ecosystem indicator and the degree of ecosystem consistency; (4) monitor the indicator in each management zone; (5) define fuzzy sets based on the observed indicator in each management zone; and (6) combine the fuzzy sets defined on the observed indicator and the fuzzy relations between the indicator and the degree of ecosystem consistency to reach conclusions about the most likely degree of consistency for alternative management actions in each management zone. The fuzzy adaptive management approach proposed here is advantageous when the benefits of avoiding the decision errors inherent with crisp and stochastic decision rules outweigh the added cost of implementing the approach. 相似文献
986.
China is a country with multinationalities. The political, social, and economic significances of the economic and social development in the minority areas have a very close connection with the modernization of the whole China's politics, society, and economy. The movement of minority rural migrants to the urban areas or to the nonagricultural industries is one of the key issues in the economic and social development in the minority rural areas. The rural population migration in the minority areas was taken as the important research topic, hoping to be of benefit to the deeper understanding of the current migration movement in China. 相似文献
987.
TIMOTHY R. McCLANAHAN 《Conservation biology》2010,24(6):1519-1528
Abstract: The adoption of fisheries closures and gear restrictions in the conservation of coral reefs may be limited by poor understanding of the economic profitability of competing economic uses of marine resources. Over the past 12 years, I evaluated the effects of gear regulation and fisheries closures on per person and per area incomes from fishing in coral reefs of Kenya. In two of my study areas, the use of small‐meshed beach seines was stopped after 6 years; one of these areas was next to a fishery closure. In my third study area, fishing was unregulated. Fishing yields on per capita daily wet weight basis were 20% higher after seine‐net fishing was stopped. The per person daily fishing income adjacent to the closed areas was 14 and 22% higher than the fishing income at areas with only gear restrictions before and after the seine‐net restriction, respectively. Incomes differed because larger fish were captured next to the closed area and the price per weight (kilograms) increased as fish size increased and because catches adjacent to the closure contained fish species of higher market value. Per capita incomes were 41 and 135% higher for those who fished in gear‐restricted areas and near‐closed areas, respectively, compared with those who fished areas with no restrictions. On a per unit area basis (square kilometers), differences in fishing income among the three areas were not large because fishing effort increased as the number of restrictions decreased. Changes in catch were, however, larger and often in the opposite direction expected from changes in effort alone. For example, effort declined 21% but nominal profits per square kilometer (not accounting for inflation) increased 29% near the area with gear restrictions. Gear restrictions also reduced the cost of fishing and increased the proportion of self‐employed fishers. 相似文献
988.
International projects frequently struggle with the dilemmas of community participation, whether the community in question
is the object of a development or aid intervention, or is to be persuaded to cooperate on a conservation project. This paper
discusses the challenges facing interventionists and the obstacles and opportunities that local people encounter as they come
into contact with exogenous conservation and development projects. The key issues presented can be summarized as legacy, legitimacy,
agency and communication. We argue that project planners need to understand the history of past interventions in order to
respond appropriately to local expectations. At the same time, the complexity of community leadership and representation complicates
the sometimes conflicting agendas of project developers and communities. Much depends on personal relations, individual agency,
and initiative. Finally, the physical means of communication—language, print and broadcast media, transport and telecommunications—are
important aspects to consider when assessing the limitations to community participation. Although there have been valuable
successes in international projects in Russia, as in other regions of the world, a better understanding of community participation
is needed to ensure more effective and sustainable means for engaging communities in project development and implementation.
This paper explores these questions through a locally-grounded analysis based on the academic research and practitioner experience
of the two authors in the remote home of a World Heritage site—the Kamchatka Peninsula, in the Russian Far East. 相似文献
989.
昆明“3·29”森林火灾对防控林区火灾的启示 总被引:2,自引:1,他引:1
李世友 《中国安全生产科学技术》2009,5(6):48-52
介绍昆明的“3·29”森林火灾基本情况。在对该火烧迹地进行3年跟踪调研的基础上,总结了该火灾对防控西南林区森林火灾的6点启示:(1)紫茎泽兰入侵区应慎修生土隔火带;(2)通过发挥山沟的阻火作用、营林防火、森林可燃物制炭等技术措施构建阻火林分;(3)重视森林火灾次生灾害;(4)开发新型森林灭火剂及施用技术;(5)适时运用以火灭火战术;(6)探索与集体林权制度改革相适应的森林消防对策。 相似文献
990.
Allison H. Roy William D. Shuster 《Journal of the American Water Resources Association》2009,45(1):198-209
Abstract: Although total impervious area (TIA) is often used as an indicator of urban disturbance, recent studies suggest that the subset of impervious surfaces that route stormwater runoff directly to streams via stormwater pipes, called directly connected impervious area (DCIA), may be a better predictor of stream ecosystem alteration. We evaluated the differences between TIA and DCIA in the Shepherd Creek catchment, a small (1.85‐km2), suburban basin in Cincinnati, Ohio. Imperviousness determinations were calculated based on publicly available geographic information system (GIS) data and parcel‐scale field assessments, and these direct assessments were compared to DCIA calculated from published, empirical relationships. Impervious and semi‐impervious area comprised 13.1% of the catchment area, with 56.3% of the impervious area connected. When summarized by subcatchments (0.26‐1.85 km2), TIA measured in the field (11‐23%) was considerably higher than that calculated from the National Land Cover Data Imperviousness Layer (7‐18%). In contrast, TIA calculated based on aerial photos was similar to TIA calculated from field assessments, thus indicating that photo interpretation may be adequate for catchment‐scale (>25 ha) TIA determinations. While these GIS data sources can be used to calculate TIA, on‐site assessments were necessary to accurately determine DCIA within residential parcels. There was a wide variation in percent connectivity across parcels, and, subsequently, DCIA was not accurately predicted from empirical relationships with TIA. We discuss applications of DCIA data that highlight the importance of parcel‐scale field assessments for managing suburban watersheds. 相似文献