首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   45篇
  免费   0篇
安全科学   8篇
废物处理   1篇
环保管理   4篇
综合类   7篇
基础理论   14篇
污染及防治   9篇
评价与监测   1篇
灾害及防治   1篇
  2019年   2篇
  2017年   1篇
  2015年   1篇
  2014年   2篇
  2013年   1篇
  2012年   1篇
  2011年   4篇
  2010年   3篇
  2009年   2篇
  2008年   1篇
  2007年   2篇
  2006年   3篇
  2005年   4篇
  2004年   6篇
  1999年   1篇
  1998年   1篇
  1995年   2篇
  1992年   1篇
  1991年   1篇
  1989年   1篇
  1987年   1篇
  1985年   2篇
  1984年   1篇
  1938年   1篇
排序方式: 共有45条查询结果,搜索用时 15 毫秒
1.
In the dry forest of southern Madagascar, a region of global conservation priority, formally protected areas are nearly totally absent. We illustrate how the continued existence of unique forest habitats in the Androy region is directly dependent on informal institutions, taboos, regulating human behavior. Qualitative interviews to map and analyze the social mechanisms underlying forest protection have been combined with vegetation analyses of species diversity and composition. Of 188 forest patches, 93% were classified as protected, and in Southern Androy all remaining forest patches larger than 5 ha were protected. Eight different types of forests, with a gradient of social fencing from open access to almost complete entry prohibitions, were identified. Transgressions were well enforced with strong sanctions of significant economic as well as religious importance. Analyses of species diversity between protected and unprotected forests were complicated because of size differences and access restrictions. However, since, for example, in southern Androy >90% of the total remaining forest cover is protected through taboos, these informal institutions represent an important, and presently the only, mechanism for conservation of the highly endemic forest species. We conclude that social aspects, such as local beliefs and legitimate sanctioning systems, need to be analyzed and incorporated along with biodiversity studies for successful conservation.  相似文献   
2.
National authorities in many countries aim at having climate change adaptation mainstreamed into existing policy domains in order to achieve coherence and synergies, and to avoid mal-adaptation. Because of local variations in climate change impacts, the lion's share of climate adaptation work will have to take place at the local level. This means also that the mainstreaming process needs to occur locally. This article examines the mainstreaming of climate change adaptation into existing sectors in five Norwegian municipalities. Applying theories of mainstreaming and policy integration we find that policy development is slower, but perhaps more robust in the municipalities that have chosen a horizontal, cross-sectoral approach to mainstreaming than in the municipalities that have chosen a vertical sector approach to mainstreaming.  相似文献   
3.
Mate sampling behaviour of black grouse females (Tetrao tetrix)   总被引:2,自引:0,他引:2  
We studied female mate sampling behaviour in lekking black grouse (Tetrao tetrix). Females mainly visited males occupying territories in the centre of the lek with relatively large territories. They were also more likely to visit males that had high attendance. The same factors were also correlated with male mating success. A multiple regression model including these factors explained more of the variance in female visits per male (53%) than in mating success (33%). The pattern of female sampling conformed with a pool comparison (best-of-n) tactic. Such a tactic is expected if the costs of sampling are low. Females of high body mass visited more males than lighter females, however, which indicates that females may vary in their search tactics and suggests that there may be search costs. The existence of costs is further suggested by the fact that if the mate from a previous year was still present, females always mated with the same male in the following year. Though search costs were not measured directly, our findings suggest that some costs are negligible (e.g. energetic exhaustion or predation) whereas others (timing of mating) may be more important.  相似文献   
4.
尤其在判断气候变化可能带来的影响时,事实证明有必要对受到显著的外部影响的有限海域的水更新速度进行评估.随SWECLIM项目一起,上述工作已在波罗的海的两个生态敏感的次盆地(即里加湾和格但斯克湾)中开展.为此目的,我们已分别以质量平衡收支和拉格朗日轨迹线为基础,采用了两种方法上不同的做法.与采用拉格朗日技术获取的结果相比,事实证明,在作为一个在形态上受到极大约束的盆地的里加湾中,使用这种箱状模型方法非常合适,而在将它用于以更加开阔的地形条件为特点的格但斯克湾时却表现出一些不足.  相似文献   
5.
Summary The social organization of the pipistrelle bat (Pipistrellus pipistrellus) was studied by means of bat boxes in southern Sweden. The males set up territories around a roosting site in the beginning of the summer at the same time as the females formed nursing colonies. After breeding, the females joined the single males in their day roosts establishing transient mating harems. Subsequently, immatures arrived at the mating grounds. The immature females, which probably attained sexual maturity during their first autumn, were admitted to the day roosts of the harem males, in contrast to the immature males. The size of the harem was dependent on the total number of females present on the mating grounds. The size, however, was also restricted by some factor, presumably the quantity of food resources in the surroundings of the specific roost site, or the capability of the harem male for mating. The mating system in the pipistrelle bat is best characterized as a resource defence polygyny. Available data on other related temperate species indicate a similar social organization in Pipistrellus nathusii and Nyctalus noctula.  相似文献   
6.
Many services generated by forest ecosystems provide essential support for human well-being. However, the vulnerability of these services to environmental change such as forest fragmentation are still poorly understood. We present spatial modeling of the generation of ecosystem services in a human-dominated landscape where forest habitat patches, protected by local taboos, are located in a matrix of cultivated land in southern Madagascar. Two ecosystem services dependent on the forest habitats were addressed: (1) crop pollination services by wild and semidomesticated bees (Apoidea), essential for local crop production of, for example, beans, and (2) seed dispersal services based on the presence of ring-tailed lemurs (Lemur catta). We studied the vulnerability of these ecosystem services to a plausible scenario of successive destruction of the smallest habitat patches. Our results indicate that, in spite of the fragmented nature of the landscape, the fraction of the landscape presently covered by both crop pollination and seed dispersal services is surprisingly high. It seems that the taboo system, though indirectly and unintentionally, contributes to upholding the generation of these services by protecting the forest patches. Both services are, however, predicted to be very vulnerable to the successive removal of small patches. For crop pollination, the rate of decrease in cover was significant even when only the smallest habitat patches were removed. The capacity for seed dispersal across the landscape displayed several thresholds with habitat patch removal. Our results suggest that, in order to maintain capacity for seed dispersal across the landscape and crop pollination cover in southern Androy, the geographical location of the remaining forest patches is more crucial than their size. We argue that in heavily fragmented production landscapes, small forest patches should increasingly be viewed as essential for maintaining ecosystem services, such as agricultural production, and also should be considered in the ongoing process of tripling the area of protected habitats in Madagascar.  相似文献   
7.
This paper seeks to contribute to debates on the potential for conservation planning to engage actively with conflict. Current research in conservation planning generally approaches conflict by concentrating on the challenges of securing agreement and consensus. Recent planning literature advocates approaches that are more open to conflict. In the analysis of a Norwegian regional planning process for wild reindeer conservation, we examine how planning authorities handled conflict, and in particular how planning documents portrayed conflicts expressed during the planning process. Findings show that the aim of reaching regional consensus limited the scope of planning, and led to the exclusion of difficult issues and opposing views. Instead of engaging actively with conflict, the planning authority framed opposing positions as unplannable, and failed to recognise them as legitimate. This contributed to weakening of the legitimacy of the regional plan when put to the test.  相似文献   
8.
High-voltage (hV) transmission grids are projects of societal importance that potentially have controversial social and environmental impacts. Former research shows that public opposition is sparked by the perception of negative local impacts and unjust concessionary processes. In this paper, we complement these perspectives by assessing the institutional practices of the regulatory agencies in dealing with scientific uncertainties. The regulatory agencies’ ‘ways of doing things’ are often designed to serve policy and management needs. A critical point is that the demarcation between scientifically based facts, values and assessments is often blurred in the decision-making process. This paper draws on two Norwegian case studies to investigate how the regulatory agencies dealt with (1) electromagnetic fields and health risks and (2) overhead lines versus sea cables. We argue that ambiguities and uncertainties that arise in the hV transmission line processes create ‘trolls’, and we explore how the local inhabitants and affected stakeholders in the two cases responded to these and how it triggered further opposition. By investigating how and why trolls appear and are handled, we conclude by discussing how public opposition related to hV transmission grids may be reduced – and how some ‘trolls’ may crack.  相似文献   
9.
Sigray P  Lundberg P 《Ambio》2004,33(4-5):267-274
Direct measurements of the potential induced by motion of electrically conducting seawater through the earth's magnetic field may be used to estimate ocean transports. For the purpose of evaluating the feasibility of monitoring the Baltic climate, a number of temporary observational systems based on this principle have been established around the Swedish coast. Some results from these investigations are presented, and the study is concluded by an outlook towards the prospects for future work along these lines.  相似文献   
10.
Diurnal activity pattern of suspension-feeding arms of the infaunal brittle star Amphiura filiformis was recorded in situ by time-lapse photography at 30 m water depth in the Gullmarsfjord, west Sweden. Activity was clearly related to the photoperiod with high activity at night and low or no activity during daytime. In laboratory experiments, the activity of the arms of A. filiformis changed in relation to new manipulated photoperiods, demonstrating exogenous circadian rhythms. The time difference for the greatest change in activity of the arms between control and treatment was correlated with the photoperiodicity. The recently found microlenses and associated neural photoreceptors in ophiuroids may apply also to A. filiformis. The trade-off between efficient feeding and predator avoidance is discussed.Communicated by M. Kühl, Helsingør  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号