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91.
92.
ABSTRACT: It has been well established that the greenhouse gas loading of the atmosphere has been increasing since the mid 19th century. Consequently, shifts in the earth's radiative balance are expected with accompanying alterations to the earth's climate. With these anticipated, and perhaps already observable, changes in both global and regional climate, managers of regional water resources seek insight to the possible impacts climate change may have on their present and future water supplies. The types and degrees of impacts that climate change may have on New York City's water supply system were assessed in a study of a watershed at Allaben, New York. Hypothetical scenarios of future climate and climate change projections from three General Circulation Models (GCMs) were used in conjunction with the WatBal hydrological model and the Palmer Drought Severity Index (PDSI) to ascertain how runoff and soil moisture from this watershed may change in a warmer climate. For the worst case predictions, the results indicate that within the century of the 2000s, the watershed's air temperature may increase up to about 11°F, while its precipitation and runoff may decrease by about 13 and 30 percent, respectively. If this watershed is typical of the others within the New York City water supply system, the system's managers should consider implementing mitigation and adaptation strategies in preparation for the worst of these possible future conditions.  相似文献   
93.
新亚欧大陆桥新疆段环境灾害的灰色拓扑预测   总被引:6,自引:0,他引:6  
基于灰色系统理论中拓扑预测的理论方法 ,对新亚欧大陆桥新疆段环境灾害造成的受损长度进行了分析预测 .在对受损长度时序分布特征分析的基础上 ,给定一组阈值 ξi,并按不同的时间序列分别建立 GM(1.1)模型而得到模型群 .然后应用新亚欧大陆桥新疆段 38年(1959~1997年)的受损长度统计资料 ,对所建模型群进行了检验 ,并用此模型群对未来可能出现一定阈值范围内受损长度的年份进行了预测 .经检验 ,该模型群的原点误差范围为 0.090~6.520 ,精度范围为 72.658~ 97.134.结果表明 ,所建模型群精确度高 ,科学性较强 ,具有比较好的实用性 .  相似文献   
94.
Hurricanes devastated the Gulf coast of the USA in 2005. Hurricane Katrina, in particular, highlighted the compelling need to build more sustainable and hazard-resilient communities. Much can be learned from recovery efforts to rebuild the Gulf coast. Personal observations and interviews with planners, academics and others involved in recovery efforts inform this analysis, which focuses on New Orleans. A conceptual framework is developed and principles and operational imperatives outlined to guide action for building sustainable, hazard-resilient communities. Such communities will remain elusive unless ‘business as usual’ is confronted by a transformational process of developmental planning. Sustainable, hazard-resilient coastal communities are founded upon robust ‘critical infrastructure’ that is secured by planning and decision-making processes that enable coastal communities to build ‘layers of resilience’ to overcome ‘waves of adversity’. Planners need to take on a redefined role—as ‘new naval architects’—to design and build communities that are ‘sea-worthy’ in this age of coastal storms.
Bruce C. GlavovicEmail:
  相似文献   
95.
Arsenic was detected at concentrations exceeding the regulatory limit of 0.010 milligrams per liter (mg/L) in an off-site bedrock monitoring well downgradient of a former electroplating facility in Merrimack, New Hampshire. The bedrock underlying the site is associated with naturally occurring high concentrations of groundwater arsenic. Geochemical modeling was used to evaluate whether the arsenic in bedrock groundwater at the off-site monitoring location was site-related or naturally occurring. The hydrogeochemical signature of the off-site bedrock well did not resemble signatures of site-impacted bedrock wells. Multiple lines of evidence support that the arsenic observed in off-site bedrock groundwater was not a result of adverse impacts from site-related groundwater contamination.  相似文献   
96.
Handmer JW 《Disasters》1985,9(4):279-285
In 1977 the Government of New South Wales introduced a flood prone lands policy which attempted to break with the past emphasis on structural works. Cornerstones of the policy were the preparation of floodplain maps, and use of the 1:100 (100 year or 1%) flood to delineate floodplains and 1:20 flood for floodway definition. The fiscal and regulatory elements of the policy were to be applied more or less uniformly within the two zones. At first there was little effective opposition to the program, but this changed when large areas of Sydney, which had not been inundated since development, were mapped. Local government concern over issues of legal liability led to decisions which in turn prompted opposition to the policy from residents' action groups and property development interests. A perceived drop in property values provided the main motivation for action by residents. This pressure for change, which intensified just before the 1984 state election, saw the policy overturned.
The new policy gives local government greater responsibility for floodplain management. State authorities have withdrawn from floodplain mapping, although technical advice will continue to be provided, and there are no longer any uniform floodplain or floodway definitions. Policy implementation is to be guided by a Manual which attempts to define flood hazard in terms of both physical and social criteria.  相似文献   
97.
介绍了新研制的可降解垃圾生物消纳机的原理,并对运行试验数据进行了分析,说明该机运行良好,社会和环境效益有独特优势。  相似文献   
98.
20000~15000a.B.P.间气候最冷,生长喜冷的针叶林和干旱草原植被.在14780±700a.B.P.出现了最低海面(-154m);15000~13500a.B.P.,气候较暖湿,海面上升,生长阔叶混交林;13500~10500a.B.P.,气候有2次温暖和3次较冷,在暖期生长针阔叶混交林.较冷期则出现森林草原和草原.最低的温度比现在低5~7;一万多年来的冰后期,气候变化分为5个新冰期(包括小冰期)和5个新高温期(包括小气候最宜期).最高气温比现在高2~3℃,出现在5000~4000a.B.P.之间;最低温度比现在低3~5℃最高海面在6500~6300a.B.P.,高出现在海面4~5m.在温暖期中生长常绿一落叶阔叶林中亚热带针阔混交林;在较冷期间,生长落叶阔叶林,针叶林或草原草地.在人类影响或自然发展之结果,未来环境变化有可能向干暖气候和高海面演变,或向干冷气候和海面下降转变.这些变化将对长江中下游带来意外的灾难.  相似文献   
99.
通过对小直径锥形管的工艺分析 ,介绍了一种成形的工艺方法和措施 ;并就成形、加工模具作了详细说明  相似文献   
100.
沙腾 《污染防治技术》2006,19(6):17-19,25
生态工业园区是按照工业生态学原理,通过模拟自然生态系统,建立工业系统中“生产者-消费者-分解者”的循环途径,实现物质闭路循环和能量多级利用。文中介绍了生态工业园区的概念、分类和中国工业生态园区的建设进展。结合无锡新区生态工业园区的建设现状,提出新区的生态工业链网设计思路,通过园区成员企业之间的协同管理,以取得资源、环境与经济、社会效益的增长最大化。  相似文献   
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