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151.
基于PSR模型的三峡库区生态经济区土地生态安全评价   总被引:24,自引:0,他引:24       下载免费PDF全文
针对三峡库区生态经济区土地资源的特点及所面临的主要问题,基于PSR框架模型的发展,构建了一套评价指标体系.采用熵权赋权法确定权重,运用土地生态安全综合模型,对该区域2003~2006年的土地生态安全综合指数进行了计算.结果表明,区域土地生态安全综合指数由2003年的0.134(敏感级)升高至2006年的0.269(临界安全级),整体生态安全状态呈好转趋势,土地所受的生态压力整体上有所加大.现有土地生态安全状况的改善主要依赖于对现有土地生态问题的治理.现阶段土地的生态压力依然严峻.对2003~2006年的土地生态安全变化进行分析显示,土地生态安全综合状况已进入快速改善阶段.  相似文献   
152.
As part of its development policy to relieve rural poverty in west China, the Chinese government has introduced measures such as agricultural tax exemptions, agricultural subsidies, and scientific, technological and restructuring improvements to agriculture. Following these actions, farmers’ incomes have increased greatly and the economy in poor areas of west China has seen rapid improvements. However, agricultural restructuring, infrastructure construction and ecological restoration projects have reduced the area of land under arable farming, restricting opportunities for increasing total grain yield. Regional food security is therefore threatened and an imbalance between economic development and food security is created. Shaanxi is a representative province in west China where agricultural restructuring has resulted in large areas of arable land being converted into orchards that produce higher economic returns. This study randomly surveyed 1430 farm households in three counties in the apple-producing region of Shaanxi Province (Luochuan, Changwu and Baishui). The standard of living and household income of farmers in the fruit production areas were higher than in grain-producing areas, thus discouraging grain production. Land under agriculture in the counties studied comprised 59% orchards and 39% arable, with 2% under other uses. Per capita, 204.3 kg of grain was produced, 51% of that required for self-sufficiency. Other staple foods produced amounted to only 13.9% of that needed for self-sufficiency. As a result, nearly half of the grain needed by the community was purchased from outside, resulting in very poor regional food security. Clearly, fruit production in this region seriously affects regional food security. Coordination of relationships between rural economic development and regional food security is key for sustainable development of the regional agriculture and economy of west China.  相似文献   
153.
This article presents a system dynamics (SD) method to examine the problem of forest degradation. The model developed takes a system-oriented view of forest management, embracing both social and biophysical factors affecting deforestation. Social factors examined are socio-economic variables or elements that influence behaviour and decision-making choices at the household level. Biophysical factors are four sub-components that are considered major land uses namely, the paddy field component, rattan plantations, coffee plantations and forest stands. The model was applied in a case study located in Pasir District of East Kalimantan, Indonesia. The site covers an area that includes a protected forest and a privately allocated timber license concession. Three village communities are examined in the case study. The SD model developed was applied to the case study focusing on three management policies or scenarios, which are based on access rights to the forest resources within the study area. Specifically, the property arrangements examined in each scenario are: Policy 1 – status quo (i.e. continue present property rights arrangements); Policy 2 – local communities manage the forest exclusively; and Policy 3 – collaborative management involving both local communities and a private company. Results from the model show that the third policy is the most viable option, and also lead to a win–win solution.  相似文献   
154.
This paper presents the status of sustainable livelihood security index (SLSI) of Karnataka, the most drought prone state in the Southern part of India. Computation of ecological security index, economic efficiency index and social equity index, and finally SLSI were carried out at the district level for the entire state, using empirical data. The selected indicators were first normalised, and then using estimated weights, indices were computed. The results indicate that the state has a very low SLSI with only 27.6% of total geographical area (TGA) and 21.7% of population being placed in the ‘sustainable’ and ‘highly sustainable’ categories (covering 10 districts) while only 34% of the TGA covering six districts falls in the ‘moderately sustainable’ category. The remaining area, confined mostly to the northern parts of the state, comprising 14 districts (51.8% of the state’s TGA) is categorised as ‘less sustainable’ and ‘very less sustainable’ exposing 44.4% (27.14 million) of state’s population to the perils of uncertain rainfall, high soil erosion rates, high social inequality and poor resource use efficiency. There is an urgent need to reorient development programmes and prioritise development investments in these vulnerable districts so that they are provided resources and opportunities to improve their ecological (more forest cover and less soil erosion), economic (higher agricultural productivity) and social (improved health and education facilities and rural infrastructure) status and achieve sustainable levels of livelihood.  相似文献   
155.
Andrea Schneiker 《Disasters》2013,37(2):244-266
Humanitarian and development agencies have confronted growing insecurity in some of the regions in which they work over the course of the past decade. Consequently, aid agencies are changing their approach to security issues. Compared to aid agencies from other countries, especially the United Kingdom and the United States, German aid agencies have been relatively slow to adopt security measures. In addition, the security measures they have selected differ from one agency to another, even in comparable security contexts. The literature on organisational learning helps to explain these differences. The findings show that external and internal organisational factors influence an aid agency's choice of a particular security measure. The different responses of German aid agencies to the changing security environment demonstrate that security measures are not only influenced by an organisation's identity but also can be a way for them to demonstrate their identity and thereby distinguish themselves from other actors that deliver aid.  相似文献   
156.
河流流域生态安全综合评估方法   总被引:9,自引:3,他引:6  
在国内外生态安全相关研究的基础上,提出了河流流域生态安全的定义. 以河流流域生态安全为研究对象,基于DPSIR(驱动力-压力-状态-影响-响应)模型框架,构建了评估指标体系,并利用多准则群体决策模型的层次分析法和熵权法确定指标权重. 以晋城市沁河流域为例,对该流域2005─2009年生态安全状况进行了综合评估. 结果表明:5年内沁河流域的生态安全综合指数从2005年的0.487升至2009年的0.641,状态从“安全”区域底部逐步提升到顶部,人均GDP增长、单位工业产值CODCr和NH3-N排放强度的降低、污水处理厂投入使用和环保投资的逐年增加是影响其变化的关键因素.   相似文献   
157.
湖泊生态安全及其评估方法框架   总被引:6,自引:1,他引:5  
针对目前我国湖泊存在的主要生态安全问题,同时考虑流域人类活动对湖泊的影响,阐述了对湖泊生态系统及湖泊生态安全的深层认识和理解,并在此基础上建立了“4+1”湖泊生态安全评估方法框架. 该方法框架包括湖泊水生态系统健康评估、流域社会经济活动对湖泊生态影响评估、湖泊生态服务功能评估和湖泊生态灾变评估,以及在这4项评估的基础上建立的湖泊生态安全综合评估. “4+1”湖泊生态安全评估方法框架既可作为对湖泊生态安全进行整体综合评估的方法,又反映了湖泊水生态健康、流域人类活动对湖泊的影响、湖泊生态服务功能以及湖泊生态灾变4个过程对湖泊生态安全的影响关系,识别影响湖泊生态安全的限制性因子. 湖泊生态安全评估启示我国湖泊管理应由水质管理向流域生态系统管理转变,其实质是解决好“人湖”关系,实现“人湖”和谐发展.   相似文献   
158.
为了弥补传统的海洋石油固定平台内部安防系统的不足,达到海洋石油固定平台全天候自动监测、自动报警、无人值守、主动防御、预防为主的目的,以便提早发现灾害或事故的苗头,提供及时报警,并采取适当的预防措施。根据主动防御、准确测报、防范未然和规避事故的原则方针,按区域警戒与要地防范相结合的方法,介绍了外部安防系统在海洋石油固定平台中的应用,包括六个子系统、工作流程、各个子系统在海洋石油固定平台中的应用以及特点和价值,从监控、应急、监管等多角度出发,实现了一体化的安全监控。  相似文献   
159.
能源安全综合评价方法探讨   总被引:6,自引:0,他引:6  
能源安全是指一个国家或地区可以获取稳定、足量、经济、清洁的能源供给,以满足需求,保障经济社会稳健运行和持续、协调发展的能力和状态。它可用加权综合模型计算得来的"能源安全度"指数进行描述,取值范围最高为1,最低为0,分值越高越安全。研究表明,现实情景下,我国能源安全度平均为0.712 5,处于"基本安全"状态。未来发展规划得当,措施得力,到2020年、2030年能源安全度可提高到0.841 1、0.847 7,进入"安全"区间。若遇针对我国的能源封锁,则能源安全度可能会降至0.552 0的"不安全"区间。解决我国能源安全问题的关键,主要是增加战略储备、实行供应多元化、加强地质勘查、发展替代能源、提高能源效益,而且能源外交也要摆在显著位置。  相似文献   
160.
The American National Standards Institute (ANSI)/American Petroleum Institute (API) Standard 780 Security Risk Assessment (SRA) Methodology was published in June 2013 as a U. S. standard for security risk assessments on petroleum and petrochemical facilities. The standard represents a model standard for evaluating all security risks of petroleum and petrochemical infrastructure and operations and assists industries in more thoroughly and consistently conducting SRAs. The 2013 Standard is an update from the previous API/NPRA SRA Methodology (2004) and focuses on expanding functional utility without changing the basic methodology.The methodology can be applied to a wide range of assets even beyond the typical operating facilities of the industry. This includes refining and petrochemical manufacturing operations, pipelines, and transportation operations including truck, marine, and rail, as well as worker and executive security, housing compounds, and remote operational sites. The new standard describes the most efficient and thorough approach for assessing security risks widely applicable to the types of facilities operated by the industry and the security issues they face. It is voluntary but has been adopted by the Kingdom of Saudi Arabia Ministry of Interior High Commission for Industrial Security as the mandatory security risk assessment methodology for industrial facilities.This paper examines the key elements of the ANSI/API SRA process and discusses how forward thinking organizations may use risk-based performance metrics to systematically analyze facility security postures and identify appropriately scaled and fiscally responsible countermeasures based on current and projected threats. The AcuTech Consulting Group developed the methodology under contract to the API, and the author was the project manager for the project.  相似文献   
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