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981.
选取具有代表性的9类共30个具体评价指标作为我国31个省(市、自治区)的综合实力评价的原始指标,运用因子多变量统计分析法对30个指标数据进行因子分析处理,采取主成分分析法提取公因子,并采取promox斜交旋转,得出6个公因子作为评价我国31个省(市、区)的综合实力的综合变量。计算得出我国各省(市、区)的综合得分。将计算的各省区市的综合得分从大到小排列,确定等级及分值区间。根据分类结果划分为6类地区,得出第Ⅰ、Ⅱ、Ⅲ类地区全部为东部地区,其综合实力得分位居全国前6位,它们依次是广东、江苏、上海、浙江、山东和北京;而第Ⅵ类地区中除海南属于东部地区之外,其余省市区都属于西部地区,其综合实力得分位居全国后7位且均为负值。它们依次是青海、宁夏.贵州、西藏、海南、甘肃和重庆。可见东西部地区社会经济发展的极度不平衡。 相似文献
982.
The dominant use of coal in power sectors has been associated with adverse environmental impacts. Ambient air monitoring for the two size fractions of particulate matter, respirable suspended particulate matter (RSPM) and non-respirable suspended particulate matter (NRSPM) in the downwind and upwind directions of a large coal-fired power station in central India, was carried out. Collected samples of ambient particulate matter were analysed atomic absorption spectrophotometrically for 15 elements. Spatial variability in elemental composition of RSPM and NRSPM and the degree of enrichment of these toxic metals in RSPM were investigated. A significant spatial variability for the elements in RSPM and NRSPM and higher degrees of enrichment of the elements were observed. 相似文献
983.
984.
Exploring public perceptions of solutions to tree diseases in the UK: Implications for policy-makers
Tree diseases are on the increase in many countries and the implications of their appearance can be political, as well as ecological and economic. Preventative policy approaches to tree diseases are difficult to formulate because dispersal pathways for pest and pathogens are numerous, poorly known and likely to be beyond human management control. Genomic techniques could offer the quickest and most predictable approach to developing a disease tolerant native ash.The population of European Ash (Fraxinus Excelsior) has suffered major losses in the last decade, due to the onset of Hymenoscyphus fraxineus (previously called Chalara Fraxinea) commonly known in the UK as ash dieback. This study presents evidence on the public acceptability of tree-breed solutions to the spread of Chalara, with the main aim to provide science and policy with an up-stream ‘steer’ on the likely public acceptability of different tree breeding solutions. The findings showed that whilst there was a firm anti-GM and ‘we shouldn’t tamper with nature’ attitude among UK publics, there was an equally firm and perhaps slightly larger pragmatic attitude that GM (science and technology) should be used if there is a good reason to do so, for example if it can help protect trees from disease and help feed the world. The latter view was significantly stronger among younger age groups (Millennials), those living in urban areas and when the (GM)modified trees were destined for urban and plantation, rather than countryside settings. Overall, our findings suggest that the UK government could consider genomic solutions to tree breeding with more confidence in the future, as large and influential publics appear to be relaxed about the use of genomic techniques to increase tolerance of trees to disease. 相似文献
985.
Using the example of bats inhabiting the Volga region, the cases in which the anthropogenic factor creates favorable conditions for these animals or significantly reduces their diversity of their fauna are considered. In this context, an opinion concerning the approaches to the conservation of bats is formulated. 相似文献
986.
土地健康与土地资源可持续利用 总被引:6,自引:0,他引:6
土地健康是伴随可持续发展战略的实施而兴起的一个土地资源研究方向,对土地资源可持续利用的实现有着很大的实践指导意义。本文在分析土地健康内涵的基础上,论述了土地健康与土地资源可持续利用的关系,并进而针对我国土地资源的特点,提出加强土地健康研究,促进土地资源可持续利用的主要对策措施。 相似文献
987.
平原地区洪灾风险评价的GIS方法研究 --以荆州6县市为例 总被引:7,自引:1,他引:6
平原地区因地势低平。水网发达而常遭到洪水的威胁。这种威胁既有来自过境洪水的洪灾.也有来自本地因暴雨引起的涝灾。如何考虑它们两者的相互影响以及洪水灾害的自然与社会经济属性,进行洪水风险评价是一个比较困难的问题。在地理信息系统软件ArcGIS8.1支持下,既考虑过境洪水与本地涝灾,也考虑承灾体的易损性(包括人口、交通线与经济),还考虑抗灾能力,以GRID模块的地图代数作为运算手段,用AHP法确定因子的权重,建立了评估平原地区的洪灾风险的计算模型和评价方法,该模型运用于长江中游洪灾风险比较严重的地区——荆州地区的6县市.取得了比较好的效果。 相似文献
988.
Ana Rosa Moreno 《Regional Environmental Change》2006,6(3):157-164
Many people would be increasingly affected by living under critical conditions in Latin America if, as expected, global warming aggravates disease and pest transmission processes. Heat waves and air pollution would increase heat-related diseases and illness episodes in large cities. Fire smoke has been associated with irritation of the throat, lung and eyes, and respiratory problems. Climate extreme increases associated with climate change would cause physical damage, population displacement, and adverse effects on food production, freshwater availability and quality. It would also increase the risks of infectious and vector-borne diseases. Climate change impacts the geographical range, seasonality, and the incidence rate of vector-borne diseases, such as malaria. Climate-related ecological changes may expand cholera transmission, particularly among populations in low-laying tropical coastal areas. El Niño conditions may affect the incidence of infectious diseases, such as malaria. Ocean warming would increase temperature-sensitive toxins produced by phytoplankton, which could cause more frequent contamination of seafood. A clearer understanding on the current role of climate change in disease patterns will be able to improve forecasts of potential future impacts of projected climate change and support action to reduce such impacts. 相似文献
989.
采用灰色系统理论的关联度分析方法,研究了涪江上游骨滑坡的主要形成条件及触发因素。结果显示,相对主同差是滑坡的主要形成条件,地震是滑坡的主要触发因素,此外,还对滑坡相关因素进行了相关显著性比较,评价了每项相关因素的其中所起的作用,最后讨论了灰色系统理论的关联度分析方法在滑坡研究中的利弊。 相似文献
990.
陕西省的地震危险趋势估计 总被引:2,自引:0,他引:2
本文应用计算某一地震带(区)上地震复发周期的公式;T_m=m×10~(bm-a)以及灰色系统理论的动态模型对陕西地区进行了地震危险趋势估计。 相似文献