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961.
随着城市化进程的加快和城市规模的迅速扩大,房屋安全使用与管理已经成为社会稳定和发展的重要课题。以上海为例,系统扼要地总结了房屋安全隐患的类型,提出房屋安全管理体系应涵盖房屋安全管理法律、房屋安全普查与检测鉴定、房屋安全技术标准、房屋安全信息系统、房屋应急抢险机制、房屋安全科普教育、专家决策咨询系统等7个方面,并对其中的主要内容做了初步的阐述。 相似文献
962.
基于遥感信息的沙漠化灾害程度定量提取研究 总被引:5,自引:4,他引:5
在分析沙漠化等级遥感信息提取现状的基础上,根据遥感手段沙漠化等级综合标志,提出了植被盖度分割和缨帽变换分割两种沙漠化程度遥感信息提取方法,并将其与传统的监督分类进行了比较.认为监督分类精度最低,植被盖度分割和缨帽变换分割更适用于生态环境动态监测,而在水体分布区缨帽变换分割较植被盖度分割适用. 相似文献
963.
黄河流域土地利用与土壤侵蚀的耦合关系 总被引:30,自引:0,他引:30
在遥感技术与GIS技术的支持下,首先通过遥感影像解译,获取了黄河流域20世纪90年代中期和末期的土地利用与土壤侵蚀数据,建立了反映该流域土地利用与土壤侵蚀的数字环境模型,而后对黄河流域近5年的土地利用与土壤侵蚀的耦合关系进行了研究.结果表明:不同的土地利用方式对土壤侵蚀的发育有着不同的影响,土地利用的变化直接影响着土壤侵蚀强度的变化,而形成土壤侵蚀的一个重要原因是土地利用方式不当.优化土地利用结构,选择合理的土地利用方式,对于高效利用土地资源,控制水土流失,实现区域经济的可持续发展具有重要意义. 相似文献
964.
在对国内外近年应用地理信息系统(GIS)解决地质学问题进行简要评述的基础上,通过实例阐述了借助于GIS技术,采用多源信息方法进行煤矿区突水预测的方法与步骤及预测结果。并展望了该方法在矿井突水预测中的应用前景。 相似文献
965.
Hakan Basaiaoclu Ertürk Celenk Miguel A. Mariulo Nurinnisa Usul 《Journal of the American Water Resources Association》1997,33(2):455-464
ABSTRACT: Geographic Information Systems (GIS) technology is used to identify candidate sites for a solid waste disposal facility in the Gölbasi region of Turkey that has suffered from the negative impact of a current but poorly-located open-dump site on the environment. The municipality of Gölbasi has noticed its deleterious effect on the environment, and has thus decided to dismiss this open-dump site and search for new landfill sites. In this study, the procedure followed under a GIS framework rejects the unacceptable sites considering environmental factors exclusively, other than economic and political issues, contained in the form of multiple layers of attribute information to select the candidate sites for landfilling wastes through an overlay analysis performed by GIS software, ARC/INFO V 7.1. For the spatial data requirements of GIS, a number of thematic map layers (ground water, wetlands and swamp areas, surface water, roads, topographic contours, ecological features, settlements, erosion susceptibility zones, and soil type) are prepared in digital form. In this application, GIS is considered as a screening tool in a site selection process to narrow the number of candidate sites, subsequently leading to one or more sites for detailed investigation. Preliminary ranking for a group of potential sites is done on the basis of simple calculations coupled with on-site field studies. 相似文献
966.
Andres R. Garcia-Martin Frederick N. Scatena Glenn S. Warner Daniel L. Civco 《Journal of the American Water Resources Association》1996,32(6):1259-1271
ABSTRACT: Statistical analysis of watershed parameters derived using a Geographical Information system (GIS) was done to develop equations for estimating the 7d–10yr, 30d–10yr, and 7d–2yr low flow for watersheds in humid montane regions of Puerto Rico. Digital elevation models and land use, geology, soils, and stream network coverages were used to evaluate 21 geomorphic, 10 stream channel, 9 relief, 7 geology, 4 climate, and 2 soil parameters for each watershed. To assess which parameters should be used for further investigation, a correlation analysis was used to determine the independence and collinearity among these parameters and their relationship with low flows. Multiple regression analyses using the selected parameters were then performed to develop the statistical models of low flows. The final models were selected in the basis of the Mallow Cp statistic, the adjusted R2, the Press statistic, the degree of collinearity, and an analysis of the residuals. In the final models, drainage density, the ratio of length of tributaries to the length of the main channel, the percent of drainage area with northeast aspect, and the average weighted slope of the drainage were the most significant parameters. The final models had adjusted standard errors of 58.7 percent, 59.2 percent, and 48.6 percent for the 7d–10yr, 30d–10yr, and 7d–2yr low flows respectively. For comparison, the best model based on watershed parameters that can be easily measured without a GIS had an adjusted standard error of 82.8 percent. 相似文献
967.
This article describes an approach to assessing spatial and temporal land-use and land-cover changes in and adjacent to protected
areas and to the measurement of landscape stability within a protected area. Methods employed include aerial photographic
interpretation and GIS technology. Odum's four-compartment ecosystem model provides the conceptual framework for assessing
landscape stability. The study area is a selected sample of the Upper San Pedro National Riparian Conservation Area in the
high desert grassland of southeastern Arizona. Significant changes were observed in the landscape matrix and riparian ecosystem.
However, when these changes were assessed in the context of Odum's model, the change was nonsignificant. Implications of the
approach and potential applications in protected area management are discussed. 相似文献
968.
Pohchin Lai 《Environmental management》1991,15(5):595-601
Many state and local agencies have begun to adopt computer technology as a means of upgrading existing mapping and related
practices. These agencies are faced with the dualism of wanting modern technology within a traditional setting and demanding
technological independence at the same time. This article is an account of the art of technology transfers, with discussions
about the necessary ingredients and constraints in the identification, adaptation, absorption, implementation, diffusion,
and evaluation of new technologies. In general, a systematic approach towards the strengthening of endogenous capabilities
with sufficient provision for operational and policy changes may be preferable to the idea of comprehensive planning. 相似文献
969.
A new method for predicting vegetation distributions using decision tree analysis in a geographic information system 总被引:4,自引:0,他引:4
Decision tree analysis was used to predict the distribution of forest communities in an area on the south coast of New South
Wales, Australia. The analysis was carried out using a geographical information system environmental data base of those topographic
and geological variables thought to influence the distribution of vegetation and derived from cartographic sources. The resulting
maps of forest communities are of a resolution sufficient to delimit individual forest stands and contain much ecological
information. 相似文献
970.
Jacqueline Nicol 《Journal of Environmental Planning and Management》1991,34(1):37-42
The paper starts by assessing some of the needs for information management within the health service in Great Britain. Geographic Information Systems are introduced, and some of the functions such as database management, networking and overlying are described. Principally, it is argued that GIS can fill the role as a health information system, resource management system, and has the potential to assist in family practitioner monitoring and epidemiological studies. 相似文献