全文获取类型
收费全文 | 8127篇 |
免费 | 584篇 |
国内免费 | 1083篇 |
专业分类
安全科学 | 255篇 |
废物处理 | 45篇 |
环保管理 | 1819篇 |
综合类 | 4306篇 |
基础理论 | 1290篇 |
环境理论 | 6篇 |
污染及防治 | 417篇 |
评价与监测 | 814篇 |
社会与环境 | 752篇 |
灾害及防治 | 90篇 |
出版年
2024年 | 45篇 |
2023年 | 143篇 |
2022年 | 235篇 |
2021年 | 301篇 |
2020年 | 308篇 |
2019年 | 209篇 |
2018年 | 204篇 |
2017年 | 323篇 |
2016年 | 361篇 |
2015年 | 373篇 |
2014年 | 423篇 |
2013年 | 472篇 |
2012年 | 510篇 |
2011年 | 624篇 |
2010年 | 435篇 |
2009年 | 532篇 |
2008年 | 434篇 |
2007年 | 533篇 |
2006年 | 493篇 |
2005年 | 397篇 |
2004年 | 388篇 |
2003年 | 323篇 |
2002年 | 272篇 |
2001年 | 214篇 |
2000年 | 214篇 |
1999年 | 176篇 |
1998年 | 131篇 |
1997年 | 120篇 |
1996年 | 86篇 |
1995年 | 94篇 |
1994年 | 110篇 |
1993年 | 69篇 |
1992年 | 49篇 |
1991年 | 33篇 |
1990年 | 20篇 |
1989年 | 14篇 |
1988年 | 17篇 |
1987年 | 7篇 |
1986年 | 16篇 |
1985年 | 9篇 |
1984年 | 11篇 |
1982年 | 11篇 |
1981年 | 6篇 |
1980年 | 8篇 |
1979年 | 11篇 |
1978年 | 8篇 |
1973年 | 6篇 |
1971年 | 3篇 |
1969年 | 2篇 |
1968年 | 2篇 |
排序方式: 共有9794条查询结果,搜索用时 62 毫秒
51.
Lisa A. Baron Tom L. Ashwood Bradley E. Sample Christopher Welsh 《Environmental monitoring and assessment》1997,47(2):153-165
The belted kingfisher (Ceryle alcyon), acommon piscivore in the eastern United States, hasbecome a common endpoint in ecological riskassessments (ERA) because of their high consumptionof potentially contaminated aquatic prey. Whilebioaccumulation data and biosurveys may be used tosupport conclusions of ERAs for kingfishers, thereare currently no published data on contaminantconcentrations in kingfishers. Additionally,methods available for collecting biological samples(e.g., feathers, eggs, food debris, etc.) fromkingfisher burrows can be detrimental to thereproductive success of the birds. We present amethod for obtaining samples from burrows during orfollowing the nesting season. The method wasapplied to kingfisher burrows on the Oak RidgeReservation (ORR) in eastern Tennessee. Feathers,eggshells, and nestlings were collected from burrows and analyzed. In addition, carcasses ofthree adult kingfishers found dead on the ORR wereanalyzed. Metals and radionuclides were accumulatedby both juvenile and adult birds. Body burdens ofcadmium, lead, and cesium-137 in adult birds were belowlevels associated with toxicity. Concentrations of selenium and mercury were observed at potentiallytoxic levels. Contaminants in eggshells andnestling feathers indicate exposure, however, thereis insufficient information to evaluate thetoxicological significance of this contamination.National Laboratory Oak Ridge National Laboratory is managed for the U.S. Department of Energy by Lockheed Martin Energy Research Corp. under contract DE-AC05-96OR22464 相似文献
52.
Andrew D. Kennedy 《Environmental monitoring and assessment》1997,48(2):173-192
Identifying process from pattern is one of the most vexing tasks inenvironmental monitoring. Given information on the distribution of speciesin a pre-defined area, together with comprehensive data on how environmentalconditions in that area have altered through time, is it possible toidentify the factors controlling the species‘ layout? Here, the practicalsignificance of this quandary is demonstrated using a series ofenvironmentally-degraded coastal lagoons in New South Wales. The TuggerahLakes (33°17′S,151°30′E) have over the last 50 yearsexperienced significant changes in species‘ distributions. Seagrasses,macroalgae, phytoplankton, molluscs, prawns and the jellyfish Catostylus mosaicus have altered in spatial pattern. Two human activitieshave been blamed for these perturbations: (1) agricultural clearance ofnative vegetation from the catchment, with associated input of top-soil andnutrients; (2) the commissioning of a coal-fired power station in 1967, withmassive uptake and recirculation of lake water for cooling purposes. In thispaper, spatial changes in macrophyte distributions over the last 50 yearsare reviewed in an attempt to identify the true source(s) of perturbation.The model adopted assumes that the power station is a point source of impactwhile nutrient inputs from the catchment are a diffuse source of impact;changes in species distributions can hypothetically be related back to thesesources according to whether they are localised or widespread. However,after a comprehensive analysis of available macrophyte data derived frominterviews, aerial photography and line transect methodologyies theconclusion is reached that changes in biogeographical pattern around theTuggerah Lakes cannot be attributed to specific anthropogenic pressures atanything beyond the coarsest of levels. This is considered to be the normfor most coastal management situations where natural background variation(’noise‘) and the complexity of linkages between physical, chemical andbiological components confounds the identification of causal relationships.The practical implications of this conclusion are discussed in the contextof litigation and remedial management design. Emphasis is placed on theneed to adopt an adaptive approach to estuarine management, incorporatingexplicit recognition of the limitations of available data, and to developnew techniques for identifying cause-effect relationships. 相似文献
53.
54.
灰色局势决策用于水环境质量的评价 总被引:3,自引:0,他引:3
按灰色系统理论的观点和方法,根据各污染因子对环境质量的不同影响,将灰色局势决策法应用于水环境质量综合评价,并与水质距离评价法,模糊综合评判法和灰色关联度分析法进行了比较,结果表明,利用灰色局势决策法进行环境质量评价,是一种有效的实用方法。 相似文献
55.
介绍了灰色关联度因子分析方法,以及此法在水污染因子分析中的应用.对于一般监测资料系列短而监测项目却较齐全的情况,应用本法是较适宜的. 相似文献
56.
57.
58.
西藏公路建设过程中的生态保护 总被引:1,自引:1,他引:1
针对西藏独特的高原生态环境特征,分析了公路建设的生态影响,提出了不同生态系统类型的生态恢复和保护措施。 相似文献
59.
环境伦理是一个伴随人类文明发展历程的社会主题。由于人类缺乏对生态文明、环境伦理、环境道德的合理吸纳,造成愈演愈烈的生态恶果。人类文明正处于历史转折点,必须对传统人类文明加以辩证之否定,融物质文明、精神文明、生态文明于一体,通过提供理性制度安排、调整利益分配格局来规范人类的道德伦理观念。 相似文献
60.
Ma Shijun 《环境科学学报(英文版)》1990,2(2):57-62
This paper concisely introduced the eco-environmental survey in China and the Chinese scientific programme for environmental research which is being practiced or being planned. China has established a nation-wide system relating to environmental scientific research and environmental administration and has taken the following strategies for solving the environment problems: (1) a series of laws and regulations for environmental protection has been promulgated so as to strengthen the legal administration and economic punishment. (2) the idea of ecological construction has been proposed for the purpose of taking the environmental protection work into the consideration of the national and provincial (or regional) economic construction planning. (3) spreading ecological engineering and ecological technologies have reduced the pollutant sources and have increased the industrial and agricultural economic profit. 相似文献