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831.
Social networks are critical to the success of behavioral interventions in conservation because network processes such as information flows and social influence can enable behavior change to spread beyond a targeted group. We investigated these mechanisms in the context of a social marketing campaign to promote a wildlife poisoning hotline in Cambodia. With questionnaire surveys we measured a social network and knowledge and constructs from the theory of planned behavior at 3 points over 6 months. The intervention initially targeted ∼11% (of 365) of the village, but after 6 months ∼40% of the population was knowledgeable about the campaign. The likelihood of being knowledgeable nearly doubled with each additional knowledgeable household member. In the short term, there was also a modest, but widespread improvement in proconservation behavioral intentions, but this did not persist after 6 months. Estimates from stochastic actor-oriented models suggested that the influences of social peers, rather than knowledge, were driving changes in intention and contributed to the failure to change behavioral intention in the long term, despite lasting changes in attitudes and perceived norms. Our results point to the importance of accounting for the interaction between networks and behavior when designing conservation interventions. 相似文献
832.
Michael?M.?WebsterEmail author Paul?J.?B.?Hart 《Behavioral ecology and sociobiology》2006,60(1):77-86
Any mechanism that allows animals to increase their foraging efficiency is likely to be selected for, including the ability
to learn to recognise and subsequently discriminate between habitat types based on their profitability. In a series of laboratory
studies, we manipulated prey densities across two different experimental subhabitats and demonstrated that threespine stickleback
(Gasterosteus aculeatus) can develop foraging preferences for subhabitats that have previously yielded prey. Fish were not recalling the spatial
location of prey patches; rather, they were discriminating between subhabitats based on foraging experience there and allocating
foraging effort accordingly. Foraging preferences took around 14 days to develop, and once established, they persisted independently
of experimental prey density, suggesting that fish were using experience rather than real-time sampling to select foraging
grounds. When we presented focal fish with social information cues, we found that they preferentially used local enhancement
and current public information cues when they conflicted with previous experience, but that they did not use prior public
information. This suggests that in the presence of conspecifics, individuals prioritise social conformity over the use of
private information. We discuss our results in the context of optimal foraging and the trade-offs associated with balancing
conflicting private and social information. 相似文献
833.
Development projects that impact wetlands commonly require compensatory mitigation, usually through creation or restoration
of wetlands on or off the project site. Over the last decade, federal support has increased for third-party off-site mitigation
methods. At the same time, regulators have lowered the minimum impact size that triggers the requirement for compensatory
mitigation. Few studies have examined the aggregate impact of individual wetland mitigation projects. No previous study has
compared the choice of mitigation method by regulatory agency or development size. We analyze 1058 locally and federally permitted
wetland mitigation transactions in the Chicago region between 1993 and 2004. We show that decreasing mitigation thresholds
have had striking effects on the methods and spatial distribution of wetland mitigation. In particular, the observed increase
in mitigation bank use is driven largely by the needs of the smallest impacts. Conversely, throughout the time period studied,
large developments have rarely used mitigation banking, and have been relatively unaffected by changing regulatory focus and
banking industry growth. We surmise that small developments lack the scale economies necessary for feasible permittee responsible
mitigation. Finally, we compare the rates at which compensation required by both county and federal regulators is performed
across major watershed boundaries. We show that local regulations prohibiting cross-county mitigation lead to higher levels
of cross- watershed mitigation than federal regulations without cross-county prohibitions. Our data suggest that local control
over wetland mitigation may prioritize administrative boundaries over hydrologic function in the matter of selecting compensation
sites. 相似文献
834.
以提高人防工程管理质量、效益、信息化为根本目的,采用计算机技术、图形学技术、数据管理技术、数据分析技术、智能技术、人机交互技术、数据交换技术、网络通信技术等,基于数字地下空间与工程,旨在建立高度综合的、统一的、开放的和真三维的人防信息系统。文章着重讨论了系统总体结构、技术结构、信息数据的获取和处理、系统的功能,并通过一工程实例说明数字地下空间与工程在人防信息系统中的应用。人防信息系统对城市人防工程设备的承载力、辐射范围缓冲区、人口疏散隐蔽最佳路径、实时监测等空间分析提供支持;对提高人防工程的管理水平、工作效率、功能发挥以及地下空间的可持续发展也将起到积极的作用,产生巨大的社会和经济效益。 相似文献
835.
836.
尚凤荣 《城市环境与城市生态》1995,(1)
本文对引进的天津水质自动监测系统在运行期间,通讯系统出现的故障作了全面的剖析研究,并提出了解决这些问题的方法。 相似文献
837.
环境影响评价需要新的突破 总被引:9,自引:0,他引:9
陈国阶 《中国人口.资源与环境》2006,16(6):149-152
中国环境影响评价已取得巨大成绩,在项目建设、区域发展中起着重要的作用,成为环境保护的重要保证手段。但中国环境影响评价依然存在十分突出的问题,还不能充分发挥其应有的功能。为此,环境影响评价应坚持正确的价值观,要打破环评单位隶属于项目建设单位的主从关系,环境单位要有独立行使调整、考察、分析、评价和下环评结论的权利;环境影响评价的时间要适时、充分,杜绝项目先上马后补环评,或项目要上马临时补环评的做法;战略环评应在宏观发展战略发挥更大的作用,成为国家宏观调控的有力工具之一;要构建环评的公共服务信息平台,反对信息部门垄断和数据虚假;环评方法贵在创新、重在实用,要积极应用新方法、新技术,反对数学方法与模型的滥用。 相似文献
838.
Water information: what is it good for? The use of information in transboundary water management 总被引:3,自引:1,他引:2
Consistent and relevant information on the status of water systems is indispensable for rational and cost-effective water management. This statement has general validity for all types of river basins, but is particularly relevant for transboundary water regions. Information is used to support decision-making and to evaluate the effects of water resources management decisions. Information production however lags behind developments in water management, which becomes clear from the fact that information still focuses on ecological components of water bodies and largely ignores the importance of socio-economic data stemming from human activities taking place in the river basin. Production of improved information is hindered by strong boundaries between different disciplines that are not easily overcome. Moreover, consideration of information needs and the goals of information dissemination prior to producing information is insufficient and the relevant actors are often reluctant to participate in these processes as they are time consuming. Differences in institutional behaviour also hinder cooperation between institutions, while organisational structures are insufficiently tuned to the needs of the external environment. All these issues hinder the use of information as the basis for decision-making. This paper provides an overview of relevant aspects of information from a broad range of perspectives and establishes the need for changes in the production and use of environmental information in support of water management. The paper is largely based on the outcomes of a closed multi-disciplinary specialist meeting on the role and use of environmental data and information in transboundary water contexts held in Arendal, Norway, September 2002. 相似文献
839.
G3技术集成及其在青藏铁路信息化中的应用研究 总被引:2,自引:0,他引:2
青藏铁路是世界上海拔最高、线路最长的高原铁路。铁路沿线环境恶劣(严寒缺氧,气候恶劣、多年冻土地段长、生态环境脆弱等)。因此,不仅要求在工程建设过程中采用先进的设备和技术手段,而且,要求在线路建成后实现其运营、维修管理信息化。笔者提出采用G3(包括全球定位系统GPS、地理信息系统GIS、全球移动通讯系统GSM)技术集成来确保建成后线路的安全运营。在集成系统中:GPS主要用于实施、快速地获取空间目标的三维坐标;GIS为系统集成提供基础平台,对空间信息进行综合分析和综合处理;GSM实现信息的无线、实时的传输。采用G3技术可以实现列车行车信息的实时发布、传输与接收,实现数据共享,从而保证行车安全。 相似文献
840.
上海城市森林综合评价研究 总被引:12,自引:1,他引:11
近年来,许多国家把发展城市森林作为实施城市可持续发展战略的一项重要内容。城市森林的综合评价在城市森林的理论研究、规划、设计和管理中具有重要的实践意义。根据城市森林评价的特点和实际,依据信息系统建设的原则和方法,以VB为开发平台,采用ESRI公司的Areobjects组件技术,设计开发了上海城市森林综合评价信息支持系统,探讨了在系统开发过程中的主要技术问题。包括系统分析与设计的原则、方法。以及系统的结构、功能设计和系统的实现等。并利用该系统对上海城市森林进行了尝试性评价。认为:上海城市森林的协调性相对较好,而城市森林生态结构有待进一步提高。 相似文献