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The thawing and subsequent decomposition of large stocks of soil organic carbon (SOC) currently stored in the northern circumpolar permafrost region are projected to result in a ‘positive’ feedback on global warming. The magnitude of this feedback can only be assessed with improved knowledge about the total size and geographic distribution of the permafrost SOC pool. This study investigates SOC storage in an under-sampled mountain permafrost area in the Russian High Altai. SOC stocks from 39 soil pits are upscaled using a GIS-based land cover classification. We found that the top 100 cm of soils in Aktru Valley and the adjacent Kuray Basin only holds on average 2.6 ± 0.6 kg C m−2 (95% confidence interval), of which only c. 1% is stored in permafrost. Global warming will result in an upward shift of alpine life zones, with new plant cover and soil development at higher elevations. As a result, this type of mountain permafrost area might act as a net C sink in the future, representing a ‘negative’ feedback on global warming.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01433-6) contains supplementary material, which is available to authorized users. 相似文献
95.
大别山区是土壤侵蚀较为强烈的地区之一,严重的土壤侵蚀不但恶化了自然环境,而且制约着该区域经济社会的可持续发展.在GIS的支持下,通过建立土壤侵蚀数据库获取有关土壤侵蚀量以及土壤侵蚀环境分析所需的基础数据,然后根据环境经济学相关的基本原理和方法对土壤侵蚀进行了货币化估算,以达到土壤侵蚀经济损失估值的目的. 相似文献
96.
The dual goals of the Organic Act of 1916 and Wilderness Act of 1964 are to protect natural resources and provide quality
visitor experiences. Park managers need metrics of trail conditions to protect park resources and quality of visitor experiences.
A few methods of sampling design for trails have been developed. Here, we describe a relatively new method, spatially balanced
sampling, and compare it to systematic sampling. We evaluated the efficiency of sampling designs to measure recreation-related
impacts in Rocky Mountain National Park. This study addressed two objectives: first, it compared estimates of trail conditions
from data collected from systematic versus spatially balanced sampling data; second, it examined the relationship between
sampling precision and sampling efficiency. No statistically significant differences in trail condition were found between
the 100-m interval and the spatially balanced datasets. The spatially balanced probability-based dataset was found to be a
good estimate of trail conditions when analyses were conducted with fewer sample points. Moreover, spatially balanced probability-based
sampling is flexible and allows additional sample points to be added to a sample. 相似文献
97.
Xie Genzong Qiu Penghua Tang Shaoxia 《中国人口.资源与环境(英文版)》2007,5(1):74-83
As the protected areas of land and coastal environment, nature reserves are designed to address how to reconcile the conservation of biodiversity, the quest for economic and social development and the maintenance of cultural values. This paper establishes a framework for nature reserve development that seeks to incorporate ecotourism into its strategies. The overall purpose was to identify the information needs required for a comprehensive nature reserve that incorporates ecotourism related values. It also illustrates the utility of this framework in the context of the Wuzhishan Mountain Region of China. A literature review, the first phase of a visionary strategy and a subsequent gap analysis for available management information were undertaken in order to achieve this paper's purpose. Finally, recommendations axe pre-sented for integrating ecotourism into nature reserve development in the Wuzhishan Mountain Region. 相似文献
98.
九华山佛茶文化旅游开发研究 总被引:3,自引:0,他引:3
九华山佛茶文化旅游既有历史优势,又有区位优势,开发九华山佛茶文化旅游是将九华山的佛教旅游资源与茶文化旅游资源中的寺院茶文化相结合。更新观念、重视特形象设计、丰富完善旅游产品、加大旅游商品开发和不断开拓旅游市场等是九华山佛茶文化旅游开发的重要举措。 相似文献
99.
Thapa GB 《Environmental management》2001,27(5):667-679
Mountain watersheds, comprising a substantial proportion of national territories of countries in mainland South and Southeast
Asia, are biophysical and socioeconomic entities, regulating the hydrological cycle, sequestrating carbon dioxide, and providing
natural resources for the benefit of people living in and outside the watersheds. A review of the literature reveals that
watersheds are undergoing degradation at varying rates caused by a myriad of factors ranging from national policies to farmers'
socioeconomic conditions. Many agencies—governmental and private—have tried to address the problem in selected watersheds.
Against the backdrop of the many causes of degradation, this study examines the evolving approaches to watershed management
and development. Until the early 1990s, watershed management planning and implementation followed a highly centralized approach
focused on heavily subsidized structural measures of soil conservation, planned and implemented without any consultation with
the mainstream development agencies and local people. Watershed management was either the sole responsibility of specially
created line agencies or a project authority established by external donors. As a consequence, the initiatives could not be
continued or contribute to effective conservation of watersheds. Cognizant of this, emphasis has been laid on integrated,
participatory approaches since the early 1990s. Based on an evaluation of experiences in mainland South and Southeast Asia,
this study finds not much change in the way that management plans are being prepared and executed. The emergence of a multitude
of independent watershed management agencies, with their own organizational structures and objectives and planning and implementation
systems has resulted in watershed management endeavors that have been in complete disarray. Consistent with the principle
of sustainable development, a real integrated, participatory approach requires area-specific conservation programs that are
well incorporated into integrated socioeconomic development plans prepared and implemented by local line agencies in cooperation
with nongovernment organizations (NGOs) and concerned people. 相似文献
100.
为了加强对黑龙江省暴雨中尺度系统的认识,有利于暴雨灾害的预报和防御,对2005年7月28-29日发生在小兴安岭的暴洪中尺度系统,从大尺度环流形势、环流演变特征、云图和雷达回波上观测到的中尺度云团的发生发展、水汽来源、产生的热力和动力条件等几方面进行了比较深入的分析。分析表明:暴雨中尺度系统是在高空槽和新生东北低涡的环境中诱发出来的;卫星和雷达图像也观测到了中-β尺度和中-α尺度的中尺度对流复合体(Mesoscale Convective complex,MCC)的发生发展;中尺度系统的水汽通道主要有两支:西南气流和偏东气流;中层冷空气的推动、风场垂直和水平切变及地形强迫抬升是这次暴洪过程中尺度系统的动力因子和触发条件。 相似文献