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351.
Abstract:  We investigated the short-term effects of forest clearcutting on land snails (terrestrial gastropods) in 15 forest stands along small streams in Sweden. Two different silvicultural treatments were applied at each site: clearcutting across the stream channel and buffer strips 10 m wide on each side of the stream. Additionally, we studied 10 reference sites in unlogged riparian forests along similar-sized streams. All sites were studied before logging and then 2.5 years after logging. After clearcutting the number of individuals in a 0.5-m2 sample from each site decreased on average from 107 to 87, and the mean number of species per sample decreased from 9.9 to 7.7. Most species were negatively affected, but there were also clear differences in sensitivity. There were correlations between species survival and ground moisture. At the wettest clearcut sites with an almost intact bryophyte cover, the land snails were unaffected by clearcutting. This result suggests that wet or moist forest floors can serve as refugia even at very small spatial scales (e.g., shallow hollows, crevices). If this is an important mechanism, the spatial distribution of small habitats could be important for the long-term survival of the snail fauna or other small, dispersal-limited organisms at clearcut sites. In the buffer strips, the number of individuals decreased but not the number of species, indicating that buffer-strip retention is a good practice for protecting land snails in riparian forests. The varying effectiveness of the buffer strip could partly be explained by the proportion of the remaining basal area, emphasizing that buffer strips could be even more effective if efforts are made to avoid heavy damage by windthrows.  相似文献   
352.
Calls for a reconnection to nature and the biosphere have been growing louder over the last decades. Cultural landscapes are rapidly changing, posing a threat to ecosystems and biodiversity, but also to human–nature connections. Human–nature connectedness may be a potential lever to shift the unsustainable trajectory that we are currently proceeding, but is also negatively influenced by it. To concretize the call for a reconnection to nature, we used the leverage points perspective on five empirical case studies with focus on human–nature connectedness. Based on the synthesis of our yearlong work, in this perspective paper, we propose four leverage points to foster a sustainability transformation: (1) maintain and enhance the structural diversity of landscapes, (2) maintain and enhance economically and ecologically sustainable small-scale agriculture, (3) strengthen sense of place and (4) strengthen sense of agency in actors. Intervening in these leverage points could be effective to foster human–nature connectedness and ultimately contribute towards a sustainable trajectory. We further argue that the interconnection between leverage points is equally important as their systemic depth.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01504-2.  相似文献   
353.
ABSTRACT

This study examined the intent, preparatory processes and challenges of nature photographers mainly shooting plants and animals in northern Japan. Findings revealed efforts to actively absorb scientific knowledge related to subjects during the preparatory process. Thus, a core intention is to capture nature in a scientifically credible manner, thereby demonstrating intimate understanding of subjects acquired from both scientific knowledge and first-hand field observations. In constructing their self-identity and attributing purpose to their work, photographers are grappling with internal tensions and contradictions when deciding the optimal distance to place between their field and related professions such as stock photography and artistic expression. We also observed cases where the original intentions of scientifically credible images from nature photographers might be lost as images are freely diffused via digital stock photo libraries. This harbors implications for the ability of the public to knowingly view photographs with a sort of “quality assurance” based on natural science.  相似文献   
354.
基于人的自私性的生态哲学分析——论生态问题   总被引:4,自引:0,他引:4  
基于对生态问题的哲学思考,从人性角度分析了该问题,承认该问题的出现是人与自然关系失衡的反映,进一步提出它与人的自私性有关,正是人性中自私的成分在资本、科技等帮助下扩张而伤害了自然。因此可努力挖掘人性更和谐的成分,加以培养,达成社会共识,以指导人们的实践,也作为预防和处理生态问题的根本措施之一。  相似文献   
355.
In many countries over the last decades, state initiatives have emerged to promote and support public participation in policy-making. Despite the emphasis on participation and deliberation, there are groups that remain outside the participatory proceedings. We follow through two case studies from Finland on how active citizen groups became excluded in the policy processes but decided to act nevertheless. Conceptually, the article tells two stories about multi-signification and improvisation in nature conservation processes from the citizen participation point of view. Using practice-oriented policy analysis, we explore the actors' conflicting interpretations of acting for “the sake of the lake”. We argue that in these kinds of complex policy processes, improvisation should be given more space.  相似文献   
356.
Management of many African game reserves is today often still an art based on experience and intuition, rather than a science. Decision-making is based on an informal integration of accumulated individual knowledge and keen field observations. Data are generally poorly captured and curated. Until fairly recently, denominators of biological parameters (such as the unit of land or unit of plant production used as measurement) have generally been treated as being homogenous. The patchiness of landscapes and the issue of ecological scaling were ignored, often because of a lack of appropriate technical tools. The ecological data available on the 49,000-ha Songimvelo Game Reserve (SGR) result from a number of discrete survey and monitoring projects undertaken by different researchers, with different objectives, at different spatial and temporal scales. A landscape ecological approach towards research and monitoring is appropriate for an area of the size and diversity of the SGR. A combination of a database approach and spatial representation was used to consolidate and integrate data across temporal and spatial scales. Herbivore spatial and temporal distribution patterns were explored across three spatial scales. An understanding was achieved of the importance of landscape patchiness in controlling resource availability for herbivores. This insight is important in guiding management and monitoring of the SGR by placing perceived patch overutilization in its proper landscape context. The landscape ecological approach bridges the traditional scale-independent view to a more contemporary scale-related understanding of ecosystem diversity and functioning.  相似文献   
357.
绿化建设是利用生态的想法(Ecological thinking)来创造人们的生活及工作空间。这样创造出来的健康而舒适的空间,不但不增加投资,实际上更能节能及减少运行费用,并改善空间用户的生产效率。所以在人居环境中引入"生态理念"是势在必行的。生态住宅生态设计是人居环境建设的关键。生态设计意识与住宅生态学已成为各国房产业、建筑业广泛关注的重点。  相似文献   
358.
作者以自己的工作经历、切身体会及悲惨遭遇,从多方面论述了自然保护区野外工作中可能发生的各种不测事件,并提出了应急对策。  相似文献   
359.
粮食储备对维护粮食安全和保障社会安定具有重大意义。在我国粮食产供需的时空差异持续加剧背景下,以省域为单元,利用空间探索性分析法研究我国近年来区域粮食储备的时空演变和地区差异,并利用空间计量模型对区域粮食储备规模的影响因素进行分析,给出分区域的粮食储备规模确定方式。结果发现:我国粮食储备具有显著空间正相关性,高储备区向东北地区扩展,低储备区进一步向西部地区转移,两者的显著集聚范围逐渐扩大,致使地区差异逐渐增大;区域粮食储备规模与粮食生产能力、人口规模、经济发展、灾害影响、交通条件和社会影响力紧密相关;综合考虑空间效应和相关因素确定区域粮食储备规模,为我国分区域粮食储备研究提供新思路。  相似文献   
360.
谢子超 《环境科技》2000,13(2):46-48
通过对人类社会发展历史的回顾,分析工业文明在人口、资源、环境等方面所造成的负面效应,引发人们探讨人与自然、人与自身、人与社会之间相互关系的依存、对立与协调统一的过程,从不同角度阐述人类社会发展在生态上、文化上、社会上、经济上可持续发展的可承受性。用东方古老哲理思想整合西方文明所带来的人类社会发展弊端,试求探索出一条“天人合一”、“东西合璧”的可持续发展之路。  相似文献   
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