全文获取类型
收费全文 | 408篇 |
免费 | 8篇 |
国内免费 | 8篇 |
专业分类
安全科学 | 11篇 |
废物处理 | 3篇 |
环保管理 | 179篇 |
综合类 | 92篇 |
基础理论 | 72篇 |
污染及防治 | 29篇 |
评价与监测 | 21篇 |
社会与环境 | 14篇 |
灾害及防治 | 3篇 |
出版年
2023年 | 4篇 |
2022年 | 2篇 |
2021年 | 11篇 |
2020年 | 11篇 |
2019年 | 3篇 |
2018年 | 6篇 |
2017年 | 8篇 |
2016年 | 17篇 |
2015年 | 9篇 |
2014年 | 8篇 |
2013年 | 19篇 |
2012年 | 8篇 |
2011年 | 39篇 |
2010年 | 18篇 |
2009年 | 42篇 |
2008年 | 29篇 |
2007年 | 17篇 |
2006年 | 17篇 |
2005年 | 14篇 |
2004年 | 13篇 |
2003年 | 10篇 |
2002年 | 13篇 |
2001年 | 11篇 |
2000年 | 13篇 |
1999年 | 8篇 |
1998年 | 9篇 |
1997年 | 7篇 |
1996年 | 4篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 5篇 |
1990年 | 6篇 |
1989年 | 4篇 |
1988年 | 9篇 |
1987年 | 5篇 |
1986年 | 3篇 |
1985年 | 2篇 |
1984年 | 4篇 |
1983年 | 2篇 |
1981年 | 1篇 |
1980年 | 1篇 |
排序方式: 共有424条查询结果,搜索用时 15 毫秒
281.
针对雨水的南方丘陵城市环境景观基础设施网络问题,以雨水排泄和汇集为导向,以GIS为分析工具,计算出雨水汇集点和排泄路径的适宜性分析图,结合城市内现有环境,如公园、广场、废弃地、绿地等用地选择环境景观基础设施节点,根据现有城市用地布局、水系、道路系统,具体计算出这些环境景观设施廊道,构建一个多功能景观基础设施网络体系,在一定程度上缓解环境雨水内涝问题,同时又能改善城市景观环境,促进城市环境景观基础设施与城市环境基础设施的融合. 相似文献
282.
Effects of habitat and landscape fragmentation on humans and biodiversity in densely populated landscapes 总被引:3,自引:0,他引:3
Manuela Di Giulio Rolf Holderegger Silvia Tobias 《Journal of environmental management》2009,90(10):2959-2968
Landscape fragmentation has often been seen as an only ecological problem. However, fragmentation also has a societal perspective, namely, in how humans perceive landscape fragmentation and in how landscape fragmentation potentially influences human well-being. These latter aspects have rarely been addressed so far. The inter-relationship of ecological and human dimensions of landscape fragmentation becomes especially evident when looking at the landscape where most people in industrial countries live, namely in suburban and urban areas. In these areas, landscape planners and environmental managers are confronted with the problem that landscapes should fullfil various functions, often with conflicting goals, e.g. nature reserves to enhance species richness vs. recreational areas for city-dwellers. We reviewed the ecological and sociological literature relevant for fragmentation in suburban and urban landscapes. In an interdisciplinary approach, we evaluated whether there are similarities and dissimilarities between the ecological and the human aspects of landscape fragmentation. We found important similarities. An example is that for both, humans and biodiversity, the loss of semi-natural areas has more drastic effects than the fragmentation of these areas per se. However, there are also relevant differences. We concluded that in densely populated landscapes a shift from responsive planning to an intentional design of environments is therefore needed. 相似文献
283.
Otero Pastor I Casermeiro Martínez MA Ezquerra Canalejoa A Esparcia Mariño P 《Journal of environmental management》2007,85(1):204-214
Landscape evaluation is now widely recognised as a powerful, interdisciplinary, environmental research method. The aim of the present work was to compare two landscape evaluation methods as part of a physical planning process: the cartographic assessment method and the in situ assessment method. This comparison was performed using an area of the Montes de Toledo, in the centre of Spain. Both methods provided similar results for the majority of the landscape units studied. This shows that the cartographic method can be successfully used in landscape evaluation, allowing important savings in terms of fieldwork. However, this is only the case when the information provided by the available maps is sufficiently accurate to allow the correct assignment of coefficients by a panel of experts. 相似文献
284.
The extent of wetland in New Zealand has decreased by approximately 90% since European settlement began in 1840. Remaining
wetlands continue to be threatened by drainage, weeds, and pest invasion. This article presents a rapid method for broad-scale
mapping and prioritising palustrine and estuarine wetlands for conservation. Classes of wetland (lacustrine, estuarine, riverine,
marine, and palustrine) were mapped using Landsat ETM+ imagery and centre-points of palustrine and estuarine sites as ancillary
data. The results shown are for the Manawatu–Wanganui region, which was found to have 3060 ha of palustrine and 250 ha of
estuarine wetlands. To set conservation priorities, landscape indicators were computed from a land-cover map and a digital
terrain model. Four global indicators were used (representativeness, area, surrounding naturalness, and connectivity), and
each was assigned a value to score wetland sites in the region. The final score is an additive function that weights the relative
importance of each indicator (i.e., multicriteria decision analysis). The whole process of mapping and ranking wetlands in
the Manawatu–Wanganui region took only 6 weeks. The rapid methodology means that consistent wetland inventories and ranking
can now actually be produced at reasonable cost, and conservation resources may therefore be better targeted. With complete
inventories and priority lists of wetlands, managers will be able to plan for conservation without having to wait for the
collection of detailed biologic information, which may now also be prioritised. 相似文献
285.
A spatially explicit linear, additive model was developed for quantifying site characteristics of riparian areas of the lower Cedar River, Washington, USA. The spatial complexity and distribution of combined habitat and anthropogenic landscape features were used to define habitat indices that indicate the relative quality of riparian habitats. Patches of contiguous grid cells were measured in terms of their locations, sizes, and relative degree of fragmentation. Additionally, intrapatch heterogeneity was measured to identify unique combinations of habitat and anthropogenic factors for individual grid cells within patches. Model verification indicated that existing floodplain riparian habitats received positive indices more than 90% of the time. Mean patch sizes and fragmentation indices were similar for all positive indices throughout the reaches in the valley floor. Among all reaches, reach 7 had the highest number of positive patches due to a higher degree of meandering in this reach. This procedure and model outputs provide unique screening opportunities for prioritizing management of riparian areas (e.g., conservation, restoration and enhancement). 相似文献
286.
287.
孔祥谦 《中国环境管理干部学院学报》2007,17(2):66-68
昌黎黄金海岸自然保护区的建立给当地及相邻地区带来多种效益,其中有保护生物多样性、维护海岸稳定、完善防护林等作用的生态效益;促进当地经济发展的社会效益及以生态旅游和水产养殖为主的经济效益。与此同时,也带来一些问题,如海洋执法问题。对此,保护区要建立海监机构,并与科学管理处合作,加强执法以保护生态环境。 相似文献
288.
Remotely sensed data have been used extensively for environmental monitoring and modeling at a number of spatial scales; however,
a limited range of satellite imaging systems often constrained the scales of these analyses. A wider variety of data sets
is now available, allowing image data to be selected to match the scale of environmental structure(s) or process(es) being
examined. A framework is presented for use by environmental scientists and managers, enabling their spatial data collection
needs to be linked to a suitable form of remotely sensed data. A six-step approach is used, combining image spatial analysis
and scaling tools, within the context of hierarchy theory. The main steps involved are: (1) identification of information
requirements for the monitoring or management problem; (2) development of ideal image dimensions (scene model), (3) exploratory
analysis of existing remotely sensed data using scaling techniques, (4) selection and evaluation of suitable remotely sensed
data based on the scene model, (5) selection of suitable spatial analytic techniques to meet information requirements, and
(6) cost–benefit analysis. Results from a case study show that the framework provided an objective mechanism to identify relevant
aspects of the monitoring problem and environmental characteristics for selecting remotely sensed data and analysis techniques. 相似文献
289.
Noncrop areas such as hedgerows in agricultural landscapes can perform several ecological and agronomic functions (e.g., habitat,
movement corridors, windbreak, etc.), but their dynamics and drivers of changes are often poorly known. We conducted a study
in three agricultural landscapes of southern Quebec, Canada, to assess and compare the spatial and temporal (1958–1997) dynamics
of three hedgerow networks in relation to geomorphic conditions (marine, glacial, and mixed deposit) and land-use changes.
Hedgerow networks were mapped and described in terms of their structure (density, degree of connectivity, and presence of
trees or shrubs) and their relationship to other components of the landscape (connection to woodland). Relationships were
assessed in time and space using nonparametric correlation, Mantel test, and principal components analysis (PCA). Results
show significant differences between hedgerow structure for the three landscapes and distinct temporal and spatial dynamics
that can be related to changes in management practices and agricultural policies. On marine deposits, increases in hedgerow
density did not always correspond to an increase in their degree of connectivity, suggesting a possible reduction in network
quality. On glacial deposits, hedgerow density declined following abandonment of agricultural land, but rather than disappearing,
these linear structures were integrated into adjacent brush or forested areas. Our analysis reveals the complex spatial and
temporal dynamics of the hedgerow networks and highlights the need to take into account spatial attributes such as connectivity
and connection to woodland to evaluate more accurately overall network quality. 相似文献
290.
Lowe WH 《Environmental management》2002,30(2):225-233
The movement of individuals among populations can be critical in preventing local and landscape-scale species extinctions
in systems exposed to human perturbation. Current understanding of spatial population dynamics in streams is largely limited
to the reach scale and is therefore inadequate to address species response to spatially extensive perturbation. Using model
simulations, I examined species response to perturbation in a drainage composed of multiple, hierarchically arranged stream-patches
connected by in-stream and overland pathways of dispersal. Patch extinction probability, the proportion of initially occupied
patches extinct after 25 years, was highly sensitive to the extent of species occupancy and perturbation within the drainage,
longitudinal species distribution, perturbation decay rate and the covariance pattern of stochastic effects on colonization
and extinction probabilities. Results of these simulations underscore the importance of identifying and preserving source
populations and dispersal routes for stream species in human-impacted landscapes. They also highlight the vulnerability of
headwater specialist taxa to anthropogenic perturbation, and the strong positive effect on species resilience of habitat rehabilitation
when recolonization is possible. Efforts to conserve and manage stream species may be greatly improved by accounting for landscape-scale
spatial population dynamics. 相似文献