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271.
Given that funds for biodiversity conservation are limited, there is a need to understand people's preferences for its different components. To date, such preferences have largely been measured in monetary terms. However, how people value biodiversity may differ from economic theory, and there is little consensus over whether monetary metrics are always appropriate or the degree to which other methods offer alternative and complementary perspectives on value. We used a choice experiment to compare monetary amounts recreational visitors to urban green spaces were willing to pay for biodiversity enhancement (increases in species richness for birds, plants, and aquatic macroinvertebrates) with self‐reported psychological gains in well‐being derived from visiting the same sites. Willingness‐to‐pay (WTP) estimates were significant and positive, and respondents reported high gains in well‐being across 3 axes derived from environmental psychology theories (reflection, attachment, continuity with past). The 2 metrics were broadly congruent. Participants with above‐median self‐reported well‐being scores were willing to pay significantly higher amounts for enhancing species richness than those with below‐median scores, regardless of taxon. The socio‐economic and demographic background of participants played little role in determining either their well‐being or the probability of choosing a paying option within the choice experiment. Site‐level environmental characteristics were only somewhat related to WTP, but showed strong associations with self‐reported well‐being. Both approaches are likely to reflect a combination of the environmental properties of a site and unobserved individual preference heterogeneity for the natural world. Our results suggest that either metric will deliver mutually consistent results in an assessment of environmental preferences, although which approach is preferable depends on why one wishes to measure values for the natural world. Preferencias de Cuantificación para el Mundo Natural Usando Estudios de Valor Monetario y No Monetario.  相似文献   
272.
Geodiversity—the variability of Earth's surface materials, forms, and physical processes—is an integral part of nature and crucial for sustaining ecosystems and their services. It provides the substrates, landform mosaics, and dynamic physical processes for habitat development and maintenance. By determining the heterogeneity of the physical environment in conjunction with climate interactions, geodiversity has a crucial influence on biodiversity across a wide range of scales. From a literature review, we identified the diverse values of geodiversity; examined examples of the dependencies of biodiversity on geodiversity at a site‐specific scale (for geosites <1 km2 in area); and evaluated various human‐induced threats to geosites and geodiversity. We found that geosites are important to biodiversity because they often support rare or unique biota adapted to distinctive environmental conditions or create a diversity of microenvironments that enhance species richness. Conservation of geodiversity in the face of a range of threats is critical both for effective management of nature's stage and for its own particular values. This requires approaches to nature conservation that integrate climate, biodiversity, and geodiversity at all spatial scales.  相似文献   
273.
Natural resource managers are often expected to achieve both environmental protection and economic development even when there are fundamental trade‐offs between these goals. Adaptive management provides a theoretical structure for program administrators to balance social priorities in the presence of trade‐offs and to improve conservation targeting. We used the case of Mexico's federal Payments for Hydrological Services program (PSAH) to illustrate the importance of adaptive management for improving program targeting. We documented adaptive elements of PSAH and corresponding changes in program eligibility and selection criteria. To evaluate whether these changes resulted in enrollment of lands of high environmental and social priority, we compared the environmental and social characteristics of the areas enrolled in the program with the characteristics of all forested areas in Mexico, all areas eligible for the program, and all areas submitted for application to the program. The program successfully enrolled areas of both high ecological and social priority, and over time, adaptive changes in the program's criteria for eligibility and selection led to increased enrollment of land scoring high on both dimensions. Three factors facilitated adaptive management in Mexico and are likely to be generally important for conservation managers: a supportive political environment, including financial backing and encouragement to experiment from the federal government; availability of relatively good social and environmental data; and active participation in the review process by stakeholders and outside evaluators. Mejorando los Objetivos Ambiental y Social Mediante el Manejo Adaptativo en el Programa de Pagos por Servicios Hidrológicos en México  相似文献   
274.
This paper reports the results of a complete national survey to measure utilization rates of prenatal cytogenetic diagnosis (P.C.D.) in women of advanced maternal age in Australia. P.C.D. has been available throughout Australia for the last decade. Every laboratory in Australia providing a P.C.D. service for the years 1979–1982 took part in this study. Utilization rates (both National and State rates) by ages of mothers, are presented. Big interstate differences exist. The 1982 National P.C.D. utilization rate for pregnant women who were 40 years of age and over was 38.8 per cent, and this rate has shown an average annual increase of 9 per cent. In those four States which offered P.C.D. to pregnant women of 35 years or over the median utilization rate was 20 per cent. These Australian rates indicate an under-utilization of P.C.D. services with (in 1982) 50–80 per cent of ‘at risk’ women not being tested. Factors which influence this are discussed.  相似文献   
275.
利用餐饮废水养鱼技术的探讨   总被引:2,自引:0,他引:2  
范瑜  伏玉顺 《环境科技》2000,13(1):30-31
探讨了利用餐饮废水进行生态养殖的技术,并对餐饮废水进入养殖水域后的水质控制,必须注意的一些问题进行了分析研究.对旅游景点餐饮废水的合理利用及对环境的保护都有一定的借鉴意义.  相似文献   
276.
人类活动对生态系统服务功能的影响   总被引:50,自引:1,他引:50  
生态系统服务功能是人类可持续发展的基础,但是人类在利用生态系统提供自然资源和生存环境两个方面的多种服务功能的同时,也在强烈影响生态系统的服务功能。除部分人类活动有利于生态系统服务功能的稳定与提高外,更多地则导致了一系列危及自身生存与发展的生态环境危机与灾难。目前,生态系统服务功能受到人类活动影响的后果已成为全球面临的日益突出的重大问题和人类社会共同关注的焦点,因而人类活动对生态系统服务功能的影响愈加受到人们的重视。论文介绍了生态系统服务功能的定义,阐述了生态系统服务功能的内涵,重点分析了人类活动影响生态系统服务功能的类型、人类活动对生态系统服务功能的影响及变化趋势。在此基础上,对尚待进一步研究的内容提出了建议。  相似文献   
277.
生态系统服务价值评估研究进展及其在环境保护中的意义   总被引:2,自引:0,他引:2  
介绍了生态系统服务功能价值的国内外研究进展。对研究趋势进行了分析,并对开展生态价值评价在环境保护中的意义进行了分析。  相似文献   
278.
Selecting reserves for forest biodiversity maintenance is often done by setting criteria for components of structural elements of biodiversity, such as a volume of decaying wood. We tested how the different threshold values for the components of structural elements affect the cost-effective site selection. Using Finnish National Forest Inventory information and remote sensing data, we determined a habitat quality index and economic value for each site in Satakunta region in Finland. Moreover, we defined several sets of potential conservation targets using alternative criteria for the habitat quality index developed for the Finnish case study. These figures were used in the site selection model in order to maximize the sum of habitat index of selected areas under a given budget constraint. We found that the production possibility frontier for the outputs of timber and biodiversity is only slightly concave when using the given threshold values. Thus, the optimal combination of the outputs is sensitive to the relative values of these goods. Our results suggest that an integrated approach in forest conservation could provide to environmental managers considerable cost savings compared with current management practices. Environmental managers could also reduce conservation costs by loosening the criteria for potential conservation targets. This would not lower considerably the quality of conserved forests.  相似文献   
279.
杨青  刘耕源 《环境科学学报》2018,38(11):4527-4538
湿地生态系统服务价值越来越被人类所认可,但由于湿地生态系统结构、功能、生态过程等的复杂性及现有价值评估方法的局限性,给湿地生态系统保护工作的推进造成了一定影响.基于此,本研究在厘清沼泽、湖泊、水库/坑塘、河流及滨海湿地生态系统差异性的基础上,根据生态系统存量流量变化、生态过程带来的附加影响和全球性生态系统服务在局地的分摊及人类感受将湿地生态系统服务价值分为直接价值(增加生物量、固碳释氧、提供水源、补给地下水、增加底泥)、间接价值(净化大气、水,营养物质运移、调节温湿度、提供水电)和存在价值(调节气候、维持生物多样性、旅游休闲+航运价值、文化教育价值);然后使用能值分析方法构建了非货币量的湿地生态系统服务价值评估框架和方法学,该框架尝试解决核算缺乏统一标准、重复计算和跨空间尺度数据转化等难题;并以珠江三角洲城市群为例,核算其湿地生态系统服务价值.该研究能为湿地生态系统差异性保护与管理、生态补偿机制的确立和完善提供一定的科学依据.  相似文献   
280.
周健  官冬杰  周李磊 《环境科学学报》2018,38(11):4539-4553
生态足迹思想被引入我国后,受到了许多学者的关注,结合生态系统服务价值相关理论,可以量化生态补偿标准.本文以重庆三峡库区为研究对象,通过基于"省公顷"的模型改进方法修正模型,计算生态足迹与生态承载力,得到其空间分异特征,引入生态系统服务价值,构建基于生态足迹的三峡库区后续发展生态补偿标准模型,并计算各个区县的生态补偿标准,与其他大型库区的生态补偿结果进行对比.研究结果表明:在2010—2016年,重庆三峡库区的平均生态足迹为34586160.120 hm~2,平均生态承载力为6664208.176 hm~2,通过对重庆段的所有区县进行生态安全判断,发现全部都是处于不安全状态,需要进行生态补偿.整体上,生态补偿需补偿约54.92亿元.而人均补偿额度小于100元的有大渡口区、奉节县、石柱县、巫山县、巫溪县、云阳县和忠县7个区县,在100~200元有长寿区、丰都县、开州区和武隆区4个区县,在200~300元的有巴南区和北碚区2个区县,在300~400元的有万州区、江北区、江津区、涪陵区和南岸区5个区县,大于400元的有沙坪坝区、渝中区、渝北区和九龙坡区4个区县.随着经济发展,必定会带来生态足迹与生态承载力的改变,生态补偿额度也会相应的增加.  相似文献   
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