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981.
There are multiple challenges regarding use and governance of landscapes’ goods, functions and intangible values for ecosystem health and human well-being. One group of challenges is to measure and assess principal sustainability dimensions through performance targets, so stakeholders have transparent information about states and trends. Another group is to develop adaptive governance at multiple levels, and management of larger geographical areas across scales. Addressing these challenges, we present a framework for transdisciplinary research using multiple landscapes as place-based case studies that integrates multiple research disciplines and non-academic actors: (1) identify a suite of landscapes, and for each (2) review landscape history, (3) map stakeholders, use and non-use values, products and land use, (4) analyze institutions, policies and the system of governance, (5) measure ecological, economic, social and cultural sustainability, (6) assess sustainability dimensions and governance, and finally (7) make comparisons and synthesize. Collaboration, communication and dissemination are additional core features. We discuss barriers bridges and bridges for applying this approach.  相似文献   
982.
The aim of this study was to evaluate the effectiveness of the debriefing meetings conducted after the 1999 earthquakes in Marmara, Turkey. The sample consisted of 265 teachers, 223 of whom attended the debriefing meetings. The personal satisfaction ratings of the teachers who attended the meetings revealed that they found the sessions satisfactory. The results of the comparison between those who reported that they benefited from the meetings and those who felt they did not indicated that the first group had lower scores on all of the psychopathology measures. A comparison between 42 teachers who did not attend the meetings and a randomly chosen group of 45 teachers who did attend revealed that the two groups differed significantly in terms of their post‐traumatic stress symptom scores. The findings of the study suggest that, in general, the teachers' debriefing sessions were satisfactory.  相似文献   
983.
百善煤矿通风系统阻力测定及分析   总被引:5,自引:1,他引:4  
为掌握百善煤矿井下通风阻力分布及井下通风系统稳定性,根据百善煤矿通风系统实际情况,选择6条测定路线,采用精密气压计逐点测定法,对其通风系统阻力进行测定,全面掌握矿井通风系统的阻力分布情况。分析结果表明:百善煤矿通风系统阻力分布基本合理,风量能够满足矿井实际生产的需求,矿井通风阻力主要集中在回风段。笔者针对百善煤矿通风系统的稳定性提出了合理的建议。  相似文献   
984.
部分矿井由于受到各方面因素影响,实际生产能力不能达到设计生产能力,有些采区安装的主要通风机的通风能力大于采区实际需要风量,即主要通风机匹配的电动机不合理,不但造成经济效益的损失,而且影响矿井的本质安全。本文以嘉禾煤矿浦溪井为例,通过简述矿井主要通风机与电动机匹配的合理改造,分析其运行效果和对矿井安全的影响;并浅述改造后的经济效益。  相似文献   
985.
酸性矿井水污染已成为全球范围内较为严重的环境污染问题之一,其污染范围广泛,诱因复杂,性质多变,危害深远。酸性矿井水未经处理排放造成江湖河流酸化,地表土壤板结,水中及土壤中的重金属含量超标,导致生物体内重金属过量富集,作物死亡,从而严重地危害了人类的健康和生命安全。对于酸性矿井水的治理意义重大,刻不容缓。讨论了目前国内外常见的酸性矿井水污染的治理技术方法,并对各种方法进行了比较。  相似文献   
986.
Some invasion biologists contend their science has reached a consensus on 4 facts: cost estimates of the effects of nonindigenous species provided in papers by Pimentel et al. are credible; invasive species generally, not just predators, pose significant extinction threats; characteristic biological differences distinguish novel from native species, ecosystems, communities, and processes; and ontological dualism, which distinguishes between natural and anthropogenic processes and influences, plays a useful role in biological inquiry. I contend there is no convincing empirical evidence for any of these propositions. Leading invasion biologists cite their agreement about these propositions as evidence for them and impugn the motives of critics who believe consensus should be based on evidence not the other way around.  相似文献   
987.
Olivier Rubin 《Disasters》2020,44(2):239-261
Natural hazards not only have socioeconomic ramifications, they also have political repercussions. This paper takes stock of the fast-growing area of research linking disasters triggered by natural hazards to voting behaviour. It is based on the central tenet of voter retrospection: voters place emphasis on past events when making their selection. The study uncovers a great disparity in analysis of electoral outcomes in the wake of disasters, part of which can be explained by the different methodological choices of authors. However, the unpredictability of voting behaviour in the aftermath of disasters also points to the relevance of introducing an intermediate variable when elucidating voter movements. This variable should capture the prevailing political discourses that surround disasters, as these are likely to shape the dynamics of voter retrospection. The paper demonstrates the analytical relevance of such political discourses by contrasting political dynamics in Denmark and Sweden following the Indian Ocean tsunami on 26 December 2004.  相似文献   
988.
Evaluation of protected area effectiveness is critical for conservation of biodiversity. Protected areas that prioritize biodiversity conservation are, optimally, located and managed in ways that support relatively large and stable or increasing wildlife populations. Yet evaluating conservation efficacy remains a challenging endeavor. We used an extensive community science data set, eBird, to evaluate the efficacy of protected areas for birds across the Gulf of Mexico and Atlantic coasts of the United States. We modeled trends (2007–2018) for 12 vulnerable waterbirds that use coastal areas during breeding or wintering. We compared two types of protected areas—sites where conservation organizations implemented active stewardship or management or both to reduce human disturbance (hereafter stewardship sites) and local, state, federal, and private protected areas managed to maintain natural land cover (hereafter protected areas)—as well as unprotected areas. We evaluated differences in trends between stewardship, protected, and unprotected areas across the Gulf and Atlantic coasts as a whole. Similar to a background sample, stewardship was known to occur at stewardship sites, but unknown at protected and unprotected areas. Four of 12 target species—Black Skimmer (Rynchops niger), Brown Pelican (Pelecanus occidentalis), Least Tern (Sternula antillarum), and Piping Plover (Charadrius melodus)—had more positive trends (two to 34 times greater) at stewardship sites than protected areas. Furthermore, five target species showed more positive trends at sites with stewardship programs than unprotected sites during at least one season, whereas seven species showed more positive trends at protected than unprotected areas. No species had more negative trends at stewardship sites than unprotected areas, and two species had more negative trends at protected than unprotected areas. Anthropogenic disturbance is a serious threat to coastal birds, and our findings demonstrate that stewardship to reduce its negative impacts helps ensure conservation of vulnerable waterbirds.  相似文献   
989.
Global biodiversity indices are used to measure environmental change and progress toward conservation goals, yet few indices have been evaluated comprehensively for their capacity to detect trends of interest, such as declines in threatened species or ecosystem function. Using a structured approach based on decision science, we qualitatively evaluated 9 indices commonly used to track biodiversity at global and regional scales against 5 criteria relating to objectives, design, behavior, incorporation of uncertainty, and constraints (e.g., costs and data availability). Evaluation was based on reference literature for indices available at the time of assessment. We identified 4 key gaps in indices assessed: pathways to achieving goals (means objectives) were not always clear or relevant to desired outcomes (fundamental objectives); index testing and understanding of expected behavior was often lacking; uncertainty was seldom acknowledged or accounted for; and costs of implementation were seldom considered. These gaps may render indices inadequate in certain decision-making contexts and are problematic for indices linked with biodiversity targets and sustainability goals. Ensuring that index objectives are clear and their design is underpinned by a model of relevant processes are crucial in addressing the gaps identified by our assessment. Uptake and productive use of indices will be improved if index performance is tested rigorously and assumptions and uncertainties are clearly communicated to end users. This will increase index accuracy and value in tracking biodiversity change and supporting national and global policy decisions, such as the post-2020 global biodiversity framework of the Convention on Biological Diversity.  相似文献   
990.
Integration of environmental science in society is impeded by the large gap between science and policy that is characterised by weaknesses in societal relevance and dissemination of science and its practical implementation in policy. We analyse experiences from BONUS, the policy-driven joint Baltic Sea research and development programme (2007–2020), which is part of the European Research Area (ERA) and involves combined research funding by eight EU member states. The ERA process decreased fragmentation of Baltic Sea science and BONUS funding increased the scientific quality and societal relevance of Baltic Sea science and strengthened the science-policy interface. Acknowledging the different drivers for science producers (academic career, need for funding, peer review) and science users (fast results fitting policy windows), and realising that most scientists aim at building conceptual understanding rather than instrumental use, bridges can be built through strategic planning, coordination and integration. This requires strong programme governance stretching far beyond selecting projects for funding, such as coaching, facilitating the sharing of infrastructure and data and iterative networking within and between science producer and user groups in all programme phases. Instruments of critical importance for successful science-society integration were identified as: (1) coordinating a strategic research agenda with strong inputs from science, policy and management, (2) providing platforms where science and policy can meet, (3) requiring cooperation between scientists to decrease fragmentation, increase quality, clarify uncertainties and increase consensus about environmental problems, (4) encouraging and supporting scientists in disseminating their results through audience-tailored channels, and (5) funding not only primary research but also synthesis projects that evaluate the scientific findings and their practical use in society – in close cooperation with science users − to enhance relevance, credibility and legitimacy of environmental science and expand its practical implementation.  相似文献   
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