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451.
土地承载力是人地关系的基础表征,开展土地承载力评价可以为实施农业空间治理、制定农业发展政策等提供参考。以西藏自治区为例,基于人体每日所需热量、蛋白质和脂肪评价土地的现实承载力及其变化。评价结果表明:(1)西藏自治区土地承载指数从2004-2016年一直维持在80.66%~89.84%之间,处于平衡有余状态。(2)未来西藏自治区土地承载指数将会持续保持在87.5%之上,呈现先升后降的变化态势,在2032年达到峰值,届时土地承载指数将会超过92.56%;此后将会持续下降,在2050年将低于90%。以土地承载力评价为基础,根据未来食物消费需求变化和西藏自治区的自然条件,提出不增加农牧业开发强度,保持农牧业生产空间规模稳定,并逐步优化调整农牧业发展结构,适度降低粮食种植面积,在适宜地区扩大蔬菜、瓜果种植,以及发展草牧业经济等建议。  相似文献   
452.
Results from a 1995 survey of utility company biologists indicate that aquatic biodiversity is an emerging and poorly understood issue. As a result, there is some confusion about what aquatic biodiversity actually is, and how we can best conserve it. Only one fourth (24%) of the respondents said their company has a stated environmental policy that addresses biodiversity. Many respondents indicate that over the years they have not specifically managed for biodiversity, but have been doing that through their efforts to assure balanced indigenous populations. While regulations are still the major driver for biological work, an increasing number of companies are involved in voluntary partnerships in managing water resources. Of these voluntary partnerships, 70% have biodiversity as a goal. Biodiversity is becoming an increasingly common subject of study, and a vast majority (75%) of the respondents suggested it should be a goal for utility resource management. Conservation of aquatic biodiversity is a complex task, and to date most aquatic efforts have been directed toward fish and macroinvertebrates. Ecological research and technological development performed by the utility industry have resulted in a number of successful biopreservation and biorestoration success stories. A common theme to preserving or enhancing aquatic biodiversity is preserving aquatic habitat. Increasingly, ecosystem management is touted as the most likely approach to achieve success in preserving aquatic biodiversity. Several utilities are conducting progressive work in implementing ecosystem management. This paper presents the potential interactions between power plants and biodiversity, an overview of aquatic biodiversity preservation efforts within the electric utility industry, more detail on the results of the survey, and recent initiatives in ecosystem management.  相似文献   
453.
一体化与多中心:黄河流域水管理模式初探   总被引:3,自引:0,他引:3  
结合黄河漉域水质水量管理的现状.在分析国外流域水质水量管理方面的经验和发展趋势的基础上.提出了在黄河漉域实施水质水量一体化管理的框架建议,并对黄河广泛分布的灌区水管理提出了准多中心的制度安排建议。  相似文献   
454.
As lifecycle emissions accounting becomes more widely used in policy, it is important to understand how it has been applied. This paper analyses policy-making for two U.S. fuel regulations—the federal Renewable Fuel Standard (RFS) and the California Low Carbon Fuel Standard (LCFS)—that were pioneering not only in using life cycle assessment (LCA) in performance-based environmental regulations, but especially for including emissions from indirect land use change (ILUC). The case studies in this paper focus, in particular, on the decision to include ILUC in lifecycle emissions accounting. Tracing the development of these policies shows the key role of environmental policy entrepreneurs in advocating for ILUC emissions accounting during policy formulation. Moreover, it highlights a paradox in the use of science: although ILUC policy proponents were motivated by best available research, they were also politically enabled by scientific uncertainty and lack of understanding. Understanding this political dimension of decision-making is valuable for scholars as well as practitioners facing similar decisions.  相似文献   
455.
Samantha Melis 《Disasters》2022,46(1):226-245
The response to the earthquakes in Nepal on 25 April and 12 May 2015 was as overwhelming as the magnitude of the events themselves. Tensions between the humanitarian imperative and the post-conflict state-building agenda soon became evident. Many actors offered support by creatively complying with the state's approach, whereas others bypassed official channels completely. In post-conflict settings such as Nepal, the situation is especially complicated because of the contradiction between policies underscoring the importance of the state in the response and the reality of the fragility of the state, which often leads to the significant involvement of aid organisations. The post-conflict political landscape of Nepal shaped the contours of the response, as well as how actors decided to operate within them. This paper, based on empirical findings from four months of research, contributes to a better understanding of the intricacies of the post-conflict and post-disaster nexus in the context of a state-led response.  相似文献   
456.
陈磊  姜海 《自然资源学报》2021,36(8):1988-2005
如何在县域层面深化主体功能区治理理念与方法应用,切实提升国土空间治理效果是新时代中国自然资源管理亟需破解的现实问题。主体功能区在国土空间管制中发挥宏观整体性的基础约束作用,重点关注开发密度高、资源环境承载力弱以及关系国家粮食生态安全的空间范围。县域主体功能区划分应遵循供需双侧导向的适宜性判别思路,兼顾空间边界模糊与监管责权交叉,融合技术判别与主体协商,尽可能落实到镇、村庄行政边界之上。对连云港市赣榆区的应用研究表明:以镇行政边界作为空间边界限阈,该区可以划分出转型发展区、提质发展区、重点建设区、重点培育区、一般农业生产区、果林产业园建设区和禁止开发区等主体功能区。县域主体功能区划定及实施过程应充分考虑县级空间事权关系,构建以省级—县级政府为主体、全社会共同参与的治理与监管体系,从土地市场、政策调控和社会监督三方面形成管控决策协调互动的政策机制。  相似文献   
457.
Currently,the problem of climate change is already far beyond the category of scientific research,and it affects the economic operation mode,interests pattern,and geographical relationships and becomes the focus of global governance.During the transition period of the international economic and social development and the critical transformation period of the world geopolitical pattern reorganization,China’s industrialization is still at the intermediate stage,and tackling with climate change is also China’s internal demand under this development stage.With more influence of climate change on national competitiveness,climate change and geopolitics present complex multiple relations,and climate change in the era of geopolitical landscape gradually affected the national strategy and diplomacy.This article offered some relevant suggestions based on evaluating the new geopolitical characteristics of climate change:(1)weighing of interests and properly handling the complex relations among major powers during international climate negotiations;(2)strengthening risk judgments and actively cooperating with the United States and the European Union on energy and climate change;(3)relying on the"One Belt(Silk Road Economic Belt)and One Road(twenty-first century Maritime Silk Road)"to ensure China’s energy security and actively participating in the global energy governance;(4)strengthening the"south-south cooperation"mechanism innovation and increasing the investment.  相似文献   
458.
探索低效工业用地减量化治理对优化土地资源利用格局、促进产业升级和城市高质量发展具有重要意义。在分析低效工业用地治理复杂系统特征的基础上,建构“情境—结构—行为—结果”分析框架,以超大城市上海市为例,采用扎根分析方法,揭示减量化过程和运行机理。结果显示:(1)低效工业用地减量化具有规划限制性、公共利益性和乡村嵌入性特征,由外部环境、用地效益、主体角色和减量化治理共同构成“外缘—内核”式的复杂适应系统。(2)建设用地“天花板”刚性约束下的宏观资源—环境—发展压力与微观用地效益是减量化的外部情境;内源性主体治理能力不足与外源性主体基于公共利益主动介入共同构成基于价值共享的治理结构;刚性政策、激励政策和支持政策形成了“三元互补”系统推动了集体行动;结果则呈现出城市高质量发展与资源再配置的协调,而平衡生态保护与经济发展、解决减量化短期压力将成为持续开展减量化的重点与难点。研究结果可为长三角其他城市开展低效工业用地治理提供经验和案例的借鉴。  相似文献   
459.
Tanzania, arguably mainland Africa's most important nation for conservation, is losing habitat and natural resources rapidly. Moving away from a charcoal energy base and developing sustainable finance mechanisms for natural forests are critical to slowing persistent deforestation. Addressing governance and capacity deficits, including law enforcement, technical skills, and funding, across parts of the wildlife sector are key to effective wildlife protection. These changes could occur in tandem with bringing new models of natural resource management into play that include capacity building, corporate payment for ecosystem services, empowering nongovernmental organizations in law enforcement, greater private‐sector involvement, and novel community conservation strategies. The future of Tanzania's wildlife looks uncertain—as epitomized by the current elephant crisis—unless the country confronts issues of governance, embraces innovation, and fosters greater collaboration with the international community.  相似文献   
460.
唐宏  张新焕  杨德刚 《自然资源学报》2011,26(10):1658-1669
基于农户访谈与问卷调查,对新疆三工河流域农户的生态移民意愿、移民效果与留居意愿进行调查,并采用Logistic模型对农户移民意愿与留居意愿的主要影响因素进行分析。研究结果显示:①家庭人口数、人均纯收入、主要收入来源、非农收入比重和参与退耕还林情况是影响农户搬迁意愿的主要因素,家庭人口数量越少,非农收入比重越大,对生态环境保护重要性的认知越强,就越能接受生态移民政策;②移民工程对河谷内生态环境改善作用显著,促进了退耕还林进程,草场压力有所缓解,但移民农户没有得到妥善安置,影响了农户家庭收入,其对定居点生产条件与生活环境评价较低,42.35%的农户认为搬迁后生活质量变差;③移民农户的留居意愿普遍不强,71.92%的农户想搬回原居住地,生活质量变化、定居点灌溉条件与耕地质量是影响其留居意愿的主要因素。政府应着力改善定居点水土资源条件与基础设施建设,提供农业技术培训,鼓励外出务工,以增加农户经济收入,改善生产生活环境,加强农户移民与留居意愿,促进移民工程的顺利实施。  相似文献   
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