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921.
922.
Abstract: Habitat fragmentation is a severe threat to tropical biotas, but its long‐term effects are poorly understood. We evaluated longer‐term changes in the abundance of larger (>1 kg) mammals in fragmented and intact rainforest and in riparian “corridors” in tropical Queensland, with data from 190 spotlighting surveys conducted in 1986–1987 and 2006–2007. In 1986–1987 when most fragments were already 20–50 years old, mammal assemblages differed markedly between fragmented and intact forest. Most vulnerable were lemuroid ringtail possums (Hemibelideus lemuroides), followed by Lumholtz's tree‐kangaroos (Dendrolagus lumholtzi) and Herbert River ringtail possums (Pseudocheirus herbertensis). Further changes were evident 20 years later. Mammal species richness fell significantly in fragments, and the abundances of 4 species, coppery brushtail possums (Trichosurus vulpecula johnstoni), green ringtail possums (Pseudochirops archeri), red‐legged pademelons (Thylogale stigmatica), and tree‐kangaroos, declined significantly. The most surprising finding was that the lemuroid ringtail, a strict rainforest specialist, apparently recolonized one fragment, despite a 99.98% decrease in abundance in fragments and corridors. A combination of factors, including long‐term fragmentation effects, shifts in the surrounding matrix vegetation, and recurring cyclone disturbances, appear to underlie these dynamic changes in mammal assemblages. 相似文献
923.
通过对安徽省石英砂加工企业生产工艺流程和现场进行调查分析,得出矽尘和噪声是两种最主要的职业病危害因素,发现石英砂生产企业矽尘和噪声危害十分严重,生产作业现场未配备任何防护装备和个人防护用品,作业人员接触职业病危害的比率非常高。分析了石英砂加工企业在职业病危害防护与管理方面的欠缺与不足,提出了针对矽尘和噪声危害因素的具体工程防护措施与管理对策,从源头控制和消除职业病危害,保护劳动者的生命安全与健康。 相似文献
924.
925.
分析了目前我国航空公司在安全信息管理和安全信息管理水平综合评价方面存在的问题.从航空公司安全信息管理的实际工作出发,结合安全管理体系(SMS)中对于安全信息管理的要求,建立了航空公司安全信息管理水平评价指标体系,并针对每个评价指标建立了4个等级的评价标准.基于主成分分析方法建立了航空公司安全信息管理水平综合评价模型.按照建立的指标体系和评价标准对5家航空公司进行了安全信息管理水平评分,并以此数据为基础,利用建立的综合评价模型对5家公司的安全信息管理水平进行了综合评价和排序,针对评价结果对各航空公司提高安全信息管理水平提出了具体的建议措施. 相似文献
926.
927.
Jon Naustdalslid 《Journal of Environmental Planning and Management》2015,58(5):913-931
Management of fresh water resources meets a range of often conflicting interests. Waterways usually run across political and administrative borders and hence make management difficult and collective action politically challenging. In order to meet these challenges, multi-level bioregional approaches to water management have been called for. Such an approach is institutionalised in the EU's Water Framework Directive (WFD). This paper presents the experiences of the Morsa water sub-district in southern Norway, a pilot for implementing the WFD. The paper discusses Morsa in the light of four principles for multi-level water governance: management on a bioregional scale; polycentric governance; public participation; and an experimental approach to water governance. Contrary to widely held assumptions that collective action in polycentric networks will be difficult because actors will follow their own narrow interests, the findings demonstrate how this is not an absolute truth, and how social action cannot be fully explained by rational action theories. The analysis concludes that the relative success of Morsa relates to a complex of factors, including openness of practices and active involvement of key actors, strong but including leadership, and a knowledge based ‘hybrid’ type of multi-level network combining horizontal and vertical network governance. 相似文献
928.
Sebastiaan van Herk Jeroen Rijke Chris Zevenbergen Richard Ashley Broos Besseling 《Journal of Environmental Planning and Management》2015,58(3):554-575
Adaptive co-management and learning are paramount for integrated flood risk management. Relevant literature focuses on adaptation at the level of physical and societal systems. The level of projects and programmes is largely overlooked, but they comprise interventions that adapt our physical systems and they provide opportunities for learning to contribute to transitions of societal systems. This paper aims to increase understanding on how learning takes place and can be stimulated within a programme. The mixed-method case study of Room for the River, a €2.3 billion programme for flood risk management, shows that a programme can be organised using various governance arrangements to stimulate learning and be a means for adaptive co-management to deliver upon environmental objectives. 相似文献
929.
Monica Gruezmacher Kristof Van Assche 《Journal of Environmental Planning and Management》2015,58(11):2015-2036
We investigate natural resource governance in three indigenous communities in the Colombian Amazon. We base our analysis on an evolutionary governance model in which governance dimensions emerge as relevant through time. The less accessible of the communities represents earlier steps in governance evolution, while the more physically accessible is more integrated into the western scene. We observe how increased physical accessibility in a community brings in western governance models which hybridize with more traditional ones, influencing the couplings between the social and ecological systems. We zoom in on changing management of three commonly used palm species and illustrate how detailed studies of natural resource management contribute to understanding governance evolution. By comparing governance evolutions we were able to gain insights and improve our understanding on how natural resource management changes in communities transiting into western ways of living. In doing so we recognized points of rigidity and flexibility which might influence the social ecological systems capacity to adapt to changing conditions. 相似文献
930.
平台信息系统的批生产管理以往未受到足够的重视,分析了现行的批生产管理体系问题,从文件管理、质量和可靠性保障、工艺管理、组织管理和技术状态控制四个方面详细阐述了如何进行平台信息系统的批生产管理。 相似文献