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301.
我国生态功能区划的目标、原则与体系   总被引:32,自引:2,他引:32  
阐述了我国开展生态功能区划的背景,分析了全国生态功能区划的基本目标和任务。以生态系统科学为基础,明确了开展生态功能区划的基本原则——生态系统完整性原则。在生态系统完整性原则下。定义系统、系统边界、系统等级和认识生态系统的尺度。对生态功能区划与自然区划、农业区划以及生态地域划分之间的联系与区别进行了分析,指出从单一要素的各种自然区划,到以整体生态系统为基础的生态功能区划是协调人与自然关系、寻求自然资源保护与人类对资源的永续利用之间的平衡的认识进步。在生态系统完整性原则上,提出了我国生态功能区划体系的框架。论述了流域在生态和社会经济方面的重要性。认为以大流域为基本区划单元的划分是构建我国生态功能区划的基本方式.“生态热点”地区规划是必要的、灵活的辅助手段.  相似文献   
302.
基于DPSIR概念模型的农业可持续发展宏观分析   总被引:25,自引:0,他引:25  
DPSIR概念模型继承了PSR模型的优点,是分析评估环境系统有效工具,本文以DPISR概念模型为指导,系统分析了农业业系统的现状,塑造这一现状的驱动力和压力,探讨了农业对于互不干涉和人类健康的影响,以及实现农业可持续发展的政策响应,目的是建立农业可持续发展的指标体系和实现农业资源的优化配置,本文认为DPSIR概念模型有利于分析复杂系统的因果关系,能有效整合资源开发,环境保护和经济发展。  相似文献   
303.
In order to further ensure that the 2030 Agenda for Sustainable Development is to be implemented and the action measures of all countries are consistent, the United Nations has put forward a set of indicators to monitor and evaluate the progress of global sustainable development. This set of evaluation indicators is aimed for global and regional progress. An important feature of the evaluation indicators is that they are internationally comparable, but due to the large differences in the levels of sustainable development among countries, this framework of evaluation indicators has a disadvantage that it does not apply to tracking the progress of sustainable development at the national level. This paper focuses on the analysis of specific issues in the application of the global sustainable development indicators framework to meet the goals and targets of the UN and builds a system of evaluation indicators to assess the progress of sustainable development at the national level in China, and offers a perspective to assess China’s progress as well.  相似文献   
304.
采用溶剂热法合成了金属有机骨架材料Cu_3(BTC)_2(BTC为均苯三甲酸根),并对其进行了XRD表征。考察了刚果红初始质量浓度、溶液pH及Na~+浓度等工艺参数对Cu_3(BTC)_2吸附刚果红效果的影响,对其吸附热力学和动力学进行了研究。结果表明:刚果红初始质量浓度增大,吸附量增大,脱色率逐渐降低;酸性条件下的吸附性能好于碱性条件;Na~+对吸附具有抑制作用,Na~+的浓度越高,抑制作用越明显;Cu_3(BTC)_2对刚果红的吸附符合Langmuir吸附等温模型和准二级动力模型。  相似文献   
305.
讨论了传统的物质流分析(MFA)方法用于城市生活垃圾代谢分析的适用性及不足之处,在此基础上结合城市生活垃圾的处理流程,对传统的MFA框架进行了改进,构建了适合城市生活垃圾代谢分析的框架,并对新框架的3个模块进行了详细的说明,建立了相应的评价指标体系并给出了应用实例。城市生活垃圾循环利用系统物质代谢分析框架能够清楚地描述生活垃圾进入经济系统后的具体流向和流量,为描述城市生活垃圾的代谢情况提供了定性及定量化的分析工具。  相似文献   
306.
The need for enhanced environmental planning and management for highland aquatic resources is described and a rationale for integrated action planning is presented. Past action planning initiatives for biodiversity conservation and wetland management are reviewed. A reflective account is given of integrated action planning from five sites in China, India and Vietnam. Eight planning phases are described encompassing: stakeholder assessment and partner selection; rapport building and agreement on collaboration; integrated biodiversity, ecosystem services, livelihoods and policy assessment; problem analysis and target setting; strategic planning; planning and organisation of activities; coordinated implementation and monitoring; evaluation and revised target setting. The scope and targeting of actions are evaluated using the Driving forces, Pressures, State, Impacts and Responses framework and compatibility with biodiversity conservation and socio-economic development objectives are assessed. Criteria to evaluate the quality of planning processes are proposed. Principles for integrated action planning elaborated here should enable stakeholders to formulate plans to reconcile biodiversity conservation with the wise use of wetlands.  相似文献   
307.
Twenty-three south-Swedish public supply wells were studied to assess pesticide pollution of regional groundwater resources. Relations between pesticide occurrence, hydrogeology, and land use were analyzed using Kohonen’s Self-Organizing Maps approach. Pesticides are demonstrated to be substantially present in regional groundwater, with detections in 18 wells. Concentrations above the drinking water threshold are confirmed for nine wells. Observations indicate considerable urban influence, and lagged effects of past, less restricted use. Modern, oxic waters from shallow, unconfined, unconsolidated or fracture-type bedrock aquifers appear particularly vulnerable. Least affected waters appear primarily associated with deeper wells, anoxic conditions, and more confined sediment aquifers lacking urban influence. Comprehensive, standardized monitoring of pesticides in groundwater need to be implemented nationwide to enable sound assessments of pollution status and trends, and to develop sound groundwater management plans in accordance with the Water Framework Directive. Further, existing water protection areas and associated regulations need to be reassessed.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0548-1) contains supplementary material, which is available to authorized users.  相似文献   
308.
In this article, we describe how protecting vernal pools was discussed by experts in the northeastern United States (U.S) within the context of a theoretical policy framework. We offer insight about characteristics of feasible vernal pool policy solutions, and identify gaps in our understanding, particularly regarding conditions in states currently lacking specific vernal pool protections. Vernal pools are geographically isolated, intermittent wetlands that provide important habitat for a variety of plants and animals. Many may not be federally protected as a result of judicial decisions over the past two decades, and the rule intended to clarify what qualifies for federal protection is currently being reviewed by the courts. Thus, state or local policy approaches may be alternatives to conserving vernal pools. We interviewed vernal pool experts in the northeastern U.S. regarding approaches to vernal pool protection and analyzed their perceptions through the lens of Kingdon's ( 2011 ) multiple streams policy development framework. The framework denotes 13 characteristics of three processes associated with policy development: problem identification, policy solution development, and the impacts of politics. While analyzed for all 13 components, we found participants most often discussed feasibility of policy formulation and implementation, particularly with regard to protecting vernal pools of high value while also remaining within the bounds of what public opinion supports.  相似文献   
309.
秦毅红  郑佳翔  胡彬  杜凯 《化工环保》2017,36(5):562-565
采用离子交换法制备锌铜双金属有机骨架(Zna/HKUST-1,a=1/24,1/12,1/6,1/3,a为Zn与Cu的摩尔比),用于催化CO还原脱硝反应。采用XRD,SEM,FTIR,H2-TPR,BET等方法对Zna/HKUST-1进行了表征。表征结果表明:Zna/HKUST-1中有明显的Zn—O键和铜基金属有机骨架(HKUST-1)的结构,证明Zn成功进入了HKUST-1中;但随a的不同,Zna/HKUST-1的形貌、大小及比表面积出现了差异。实验结果表明,Zna/HKUST-1(a=1/24)对CO还原脱硝反应的催化活性最高,可在230℃达到NO转化率100%。  相似文献   
310.
Human–wildlife conflict (HWC) is a key topic in conservation and agricultural research. Decision makers need evidence-based information to design sustainable management plans and policy instruments. However, providing objective decision support can be challenging because realities and perceptions of human–wildlife interactions vary widely between and within rural, urban, and peri-urban areas. Land users who incur costs through wildlife argue that wildlife-related losses should be compensated and that prevention should be subsidized. Supporters of human–wildlife coexistence policies, such as urban-dwelling people, may not face threats to their livelihoods from wildlife. Such spatial heterogeneity in the cost and benefits of living with wildlife is germane in most contemporary societies. This Special Section features contributions on wildlife-induced damages that range from human perspectives (land use, psychology, governance, local attitudes and perceptions, costs and benefits, and HWC and coexistence theory) to ecological perspectives (animal behavior). Building on current literature and articles in this section, we developed a conceptual model to help frame HWC and coexistence dimensions. The framework can be used to determine damage prevention implementation levels and approaches to HWC resolution. Our synthesis revealed that inter- and transdisciplinary approaches and multilevel governance approaches can help stakeholders and institutions implement sustainable management strategies that promote human–wildlife coexistence.  相似文献   
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