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321.
This article proposed the concept of"climate capacity"as a way of measuring human’s adaptiveness to climate change.This article also focused on the related concepts like ecological carrying capacity,water resources carrying capacity,land carrying capacity as well as population carrying capacity.The concept of climate capacity was articulated against a background of global climate and environmental change.Essentially,China’s efforts to adapt to climate change was a matter of improving climate capacity,which is the ecosystem as well as the frequency,the intensity and the scale of human’s social activities that the climatic resources of a particular geographic area were supposed to support.The climate capacity has two components.One is the natural climate capacity,which includes temperature,sunlight,precipitation,extreme climatic events,etc.The other is the derived climate capacity,which includes water resources,land resources,ecological systems,climatic risks,etc.The climate capacity can be developed or be transferred between regions by taking engineering,technology or regime-based adaptive measures.However,these adaptive measures must be implemented under the principle of economic rationalism,ecological integrity,climate protection,and social justice.It is expected that by combining the climate capacity and its threshold value with the assessment of climate change risks,we are able to predict the optimal population carrying capacity and the scale of socioeconomic development,and furthermore,provide policy support for the socioeconomic development strategy and adaptive planning.In the regions with high climate capacity,there is a symbiotic relationship between adaptation and socioeconomic development.But,in the regions with limited climate capacity,irrational development may further damage the environment.Taking the Yangtze River delta,a region with high climate capacity,and a region of Ningxia,a region with limited climate capacity,as illustrative examples,the authors of this article analyzed the policy implications of climate capacity and further made suggestions on the problems of capacitylimited adaptation and development-driven adaptation.This article argued that the concept of climate capacity can not only be used as an analytical instrument of climate change economics,but also it can provide research support for planning regional adaptation and development with climate change impact and risk assessments.  相似文献   
322.
排污权制度是解决环境容量资源配置低效率的重要手段,可以实现环境容量资源的优化配置,已在一些国家运用,并取得一定成效,但在中国其仍处于试点的阶段,亟待理论研究的支撑。研究认为,物质平衡、外部性和产权构成了排污权制度的理论基础;排污权制度的构建和完善应着眼于制度构成的基本要素、制度特征和运行条件3个方面。  相似文献   
323.
HDPE膜-膨润土复合防污帷幕被认为是目前最为安全有效的地下污染源阻隔技术之一.针对帷幕底部嵌入不透水层和帷幕下游地下水较为活跃的工况,推导了有机污染物在HDPE膜-膨润土复合防污帷幕三层结构中的一维扩散解析解.利用本文的解析解分析了HDPE膜-膨润土复合帷幕对亲水性和疏水性两类有机污染物的阻隔效果.分析结果表明:由于亲水性有机物与HDPE膜间的分配系数低,该复合防污帷幕对其阻隔效果显著优于具有高分配系数的疏水性有机物.对于疏水性有机物,可通过增大复合帷幕中膨润土的阻滞因子和帷幕厚度来改善其阻隔效果;膨润土的阻滞因子增大10倍且帷幕厚由0.6m增大为1.0m,改进后复合帷幕对疏水性有机物的阻隔效果可达到原帷幕对低分配系数亲水性有机物的阻隔水平.工程实践中可通过对HDPE膜进行表面处理以降低其分配系数或膨润土改性以增大其阻滞因子等措施来增强该复合帷幕的阻隔效果.  相似文献   
324.
如何揭示利益相关者生态补偿的真实意愿不但是生态系统服务支付研究的难点问题,也是政府及管理部门制定生态补偿政策的关键问题。为此,论文通过对辽河流域中游地区的7个主要城市进行实地调研,采用条件价值评估法,利用同一受访者同时测量其支付意愿值(WTP)和受偿意愿值(WTA)的技术手段来检验其真实补偿意愿,研究结果显示,受访地区居民保护流域生态环境和水资源的WTP为59.39元/(人·a),WTA为248.56/(人·a);同时,针对同一受访者给出的WTP与WTA之间的较大差异性利用回归分析方法,得出其呈现不对称性的主要原因是受访者的收入水平和年龄。最后,在对研究结果进行差异性分析的基础上,提出了辽河流域生态补偿意愿差异性的研究结论和政策建议。  相似文献   
325.
Like the rest of the world, African countries are reeling from the health, economic and social effects of COVID-19. The continent’s governments have responded by imposing rigorous lockdowns to limit the spread of the virus. The various lockdown measures are undermining food security, because stay at home orders have among others, threatened food production for a continent that relies heavily on agriculture as the bedrock of the economy. This article draws on quantitative data collected by the GeoPoll, and, from these data, assesses the effect of concern about the local spread and economic impact of COVID-19 on food worries. Qualitative data comprising 12 countries south of the Sahara reveal that lockdowns have created anxiety over food security as a health, economic and human rights/well-being issue. By applying a probit model, we find that concern about the local spread of COVID-19 and economic impact of the virus increases the probability of food worries. Governments have responded with various efforts to support the neediest. By evaluating the various policies rolled out we advocate for a feminist economics approach that necessitates greater use of data analytics to predict the likely impacts of intended regulatory relief responses during the recovery process and post-COVID-19.  相似文献   
326.
2018年中共中央印发的《深化党和国家机构改革方案》对自然生态系统的保护修复和监管进行了部门划分,但由于生态系统结构、过程和功能的复杂性和多样性,在涉及生态保护修复具体工作时,依然面临着生态监管的职能边界不清晰、制度体系不健全等问题.以习近平生态文明思想为指引,借助于生物多样性和生态系统服务科学-政策平台(IPBES)概念框架,明晰了新时期生态环境部门生态监管职能的内涵,即从维护国家和区域生态安全的角度,通过监测、评估、监督、执法和考核等手段,对有关部门和地方政府所开展的生态保护修复工作进行行政监督和执法.解析了生态环境部门与自然资源部门(包括国家林草部门)在生态保护修复领域的职责关系,主要包括三方面:①二者分别通过间接与直接途径实现促进生态系统服务和产品供给提升的目标.②二者定位分别是外部“专职”监管和中央与地方、上级与下级的内部监督.③二者监督对象分别是督政与督事.针对新时期生态监管制度体系的构建,建议健全生态保护防控制度、建立“1+N”生态监测制度、构建生态评估及预警制度、健全生态保护执法制度、完善考核督察问责制度、健全公众参与监督制度和构建生态监管保障制度等,以进一步提升生态监管效能,推动生态保护修复成效提升,从而为人民群众提供更多更好的生态产品.   相似文献   
327.
在中国农村劳动力非农就业不断加速的背景下,探讨非农就业对集体林区不同规模林农营林轮伐期的影响机制,有助于明确不同规模经营主体今后的用材林营林目标和林业在山区未来的经营发展模式,同时为林业规模化经营的合理性提供客观依据。基于劳动力转移新经济学理论,通过对浙江、江西和福建三省450户林农的调查,收集杉木营林的地块投入产出数据,在此基础上,运用Faustmann模型计算规模户与普通户的理论最优轮伐期,运用计量模型分析非农就业对集体林区不同规模林农采伐轮伐期的影响机制。研究结果发现,普通户和规模户的理论最优轮伐期趋同;非农就业的劳动力流失效应造成普通户营林的预期主伐时间显著短于理论最优轮伐期,而规模户非农就业带来的收入效应造成其采伐决策接近于理论最优轮伐期。在农村非农就业不断增加背景下,南方集体林区规模化经营的方式有利于接近最优采伐决策,更适合于培育大径材,增加林业生态和经济效益。  相似文献   
328.
This article contributes to the understanding of adaptive capacity within national sectors by utilising two perspectives from institutional theory. Resting on data from 21 interviews the paper analyses the Norwegian electricity sector and the influence on adaptive capacity to climate change from changes in formal structure and institutional culture. The sector underwent transformational change between the beginning of the 1980s and mid-2000s, with the reform from 1991 as a watershed, and gradual consolidation from about 2000. From a self-regulated vertically integrated sector with an emphasis on robustness of supply the sector changed into a liberalised and unbundled structure, with economic efficiency as the guiding principle. These changes reduced adaptive capacity to climate change. After 2000, gradually adaptive capacity has increased somewhat. The paper argues that also social contextual factors need to be taken account of, both to understand adaptive capacity to climate change and to provide practitioners with an ability to increase it.  相似文献   
329.
世纪之交我国人口,资源,环境的趋势分析与对策   总被引:3,自引:1,他引:2  
本文全面分析了我国人口、资源、环境的现状;及其在“九五”和2010年的发展趋势;并提出了促进我国经济建设与人口、资源、环境协调发展的对策和建议。  相似文献   
330.
ABSTRACT: Legislative constraints on the development of water resources policy fit into three broad categories-political, institutional, and informational. The political category encompasses constituency needs and preferences, satisfaction with existing water management practices and policies, and the necessity for legislators to blend political ambition with public problem solving. Constraints fitting into the institutional category include differences in legislative behavior and attitudes that stem from one's location in the legislature (e.g., senate-house, leader-follower, or committee activity), the dynamics of scheduling and organization, and the capability to manage complex issues. Informational constraints refer to the availability of information and the use to which it is put by lawmakers in formulating decisions on waterrelated issues. These constraints are approached from a behavioral perspective by examining several constituency, institutional, and information hypotheses that “explain” legislative involvement with water resources issues. The data are drawn from a recent study of water resources decision making in West Virginia. Eighty-three of the 134 members of the 1975–76 West Virginia Legislature participated in the study.  相似文献   
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