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951.
南岳衡山国内旅游客源市场调查分析 总被引:6,自引:0,他引:6
彭蝶飞 《湖南环境生物职业技术学院学报》2003,9(1):51-57
对南岳衡山旅游客源市场进行调查分析,可为其旅游产业定位、旅游开发建设的阶段定位、旅游基础设施资源定位、旅游产品开发定位、旅游从业人员定位提供依据,从而推动整个衡山旅游业的发展,并促进其经济发展.本文通过对南岳衡山客源市场的调查分析,提出了对其市场开发定位及开拓策略的建议. 相似文献
952.
概括了自然保护区与社区的统一性和矛盾 ,分析了自然保护区与社区协调发展存在的主要问题 ,提出了自然保护区与社区协调发展的途径与方法 ,总结了一些保护区与社区协调发展的有效模式 ,包括政区合署模式、协调机构模式、保护与扶贫相结合模式、经济上双赢模式和公众参与模式 相似文献
953.
航空遥感地震灾害信息的快速提取 总被引:16,自引:1,他引:16
航空遥感地震灾害信息的快速提取是地震灾害损失快速评估的关键技术。遥感与地理信息系统的结合应用使得震害调查快速而又正确。本文重点论述了震害地类的特性与建立解译模型的原则、方法与不同种类信息源所采用的二套技术方案,并比较分析了二套技术方案各自的优势,探讨地震灾害信息快速提取的技术方法。 相似文献
954.
Luna EM 《Disasters》2001,25(3):216-226
The Philippines is very vulnerable to natural disasters because of its natural setting, as well as its socio-economic, political and environmental context--especially its widespread poverty. The Philippines has a well-established institutional and legal framework for disaster management, including built-in mechanisms for participation of the people and NGOs in decision-making and programme implementation. The nature and extent of collaboration with government in disaster preparedness and mitigation issues varies greatly according to their roots, either in past confrontation and political struggles or traditional charity activities. The growing NGO involvement in disaster management has been influenced by this history. Some agencies work well with local government and there is an increasing trend for collaborative work in disaster mitigation and preparedness. Some NGOs, however, retain critical positions. These organisations tend to engage more in advocacy and legal support for communities facing increased risk because of development projects and environmental destruction. Entry points into disaster mitigation and preparedness vary as well. Development-oriented agencies are drawn into these issues when the community members with whom they work face disaster. Relief organisations, too, realise the need for community mobilisation, and are thus drawn towards development roles. 相似文献
955.
Conservation Strategies for Endemic Fish Species Threatened by the Three Gorges Dam 总被引:14,自引:0,他引:14
YOUNG-SEUK PARK‡ JIANBO CHANG† SOVAN LEK WENXUAN CAO† SEBASTIEN BROSSE 《Conservation biology》2003,17(6):1748-1758
Abstract: The largest damming project to date, the Three Gorges Dam has been built along the Yangtze River (China), the most species-rich river in the Palearctic region. Among 162 species of fish inhabiting the main channel of the upper Yangtze, 44 are endemic and are therefore under serious threat of global extinction from the dam. Accordingly, it is urgently necessary to develop strategies to minimize the impacts of the drastic environmental changes associated with the dam. We sought to identify potential reserves for the endemic species among the 17 tributaries in the upper Yangtze, based on presence/absence data for the 44 endemic species. Potential reserves for the endemic species were identified by characterizing the distribution patterns of endemic species with an adaptive learning algorithm called a "self-organizing map" (SOM). Using this method, we also predicted occurrence probabilities of species in potential reserves based on the distribution patterns of communities. Considering both SOM model results and actual knowledge of the biology of the considered species, our results suggested that 24 species may survive in the tributaries, 14 have an uncertain future, and 6 have a high probability of becoming extinct after dam filling. 相似文献
956.
草原不同沙化地段蝗虫与植物群落多样性的变化及相互关系的数值分析 总被引:1,自引:0,他引:1
通过对植物和蝗虫种群生物量的调查,研究了宁夏盐池县干草原沙化过程中植物和蝗虫群落结构、多样性与丰富度的变化,以及其相互关系.结果表明,植物和蝗虫群落随着草地的沙化程度表现出序列性演替过程,蝗虫群落多样性直接受植物群密结构变化的影响,但二者的变化趋势并不完全平行.草地沙化对蝗虫群落多样性和丰富度是一种灾变性影响:沙化导致植被结构与土壤硬度的变化,造成蝗虫产卵地条件的改变. 相似文献
957.
958.
Performance and Environmental Impact of Biodegradable Films in Agriculture: A Field Study on Protected Cultivation 总被引:4,自引:1,他引:4
Anu Kapanen Evelia Schettini Giuliano Vox Merja Itävaara 《Journal of Polymers and the Environment》2008,16(2):109-122
The performance, the degradability in soil and the environmental impact of biodegradable starch-based soil mulching and low
tunnel films were assessed by means of field and laboratory tests. The lifetime of the biodegradable mulches was 9 months
and of the biodegradable low-tunnel films 6 months. The radiometric properties of the biodegradable films influenced positively
the microclimate: air temperature under the biodegradable low tunnel films was 2 °C higher than under the low density polyethylene
films, resulting in an up to 20% higher yield of strawberries. At the end of the cultivation period, the biodegradable mulches
were broken up and buried in the field soil together with the plant residues. One year after burial, less than 4% of the initial
weight of the biodegradable film was found in the soil. According to ecotoxicity tests, the kinetic luminescent bacteria test
with Vibrio fischeri and the Enchytraeus albidus ISO/CD 16387 reproduction potential, there was no evidence of ecotoxicity in the soil during the biodegradation process.
Furthermore, there was no change in the diversity of ammonia-oxidizing bacteria in the soil determined on the basis of the
appearance of amoA gene diversity in denaturing gradient gel electrophoresis. 相似文献
959.
From disaster to development: a systematic review of community‐driven humanitarian logistics 下载免费PDF全文
A plethora of untapped resources exist within disaster‐affected communities that can be used to address relief and development concerns. A systematic review of the literature relating to community participation in humanitarian logistics activities revealed that communities are able to form ad hoc networks that have the ability to meet a wide range of disaster management needs. These structures, characterised as Collaborative Aid Networks (CANs), have demonstrated efficient logistical capabilities exclusive of humanitarian organisations. This study proposes that CANs, as a result of their unique characteristics, present alternatives to established humanitarian approaches to logistics, while also mitigating the challenges commonly faced by traditional humanitarian organisations. Furthermore, CANs offer a more holistic, long‐term approach to disaster management, owing to their impact on development through their involvement in humanitarian logistics. This research provides the foundation for further theoretical analysis of effective and efficient disaster management, and details opportunities for policy and practice. 相似文献
960.
Being constantly connected to others via e‐mail and other online messages is increasingly typical for many employees. In this paper, we develop and test a model that specifies how interruptions by online messages relate to negative and positive affect. We hypothesize that perceived interruptions by online messages predict state negative affect via time pressure and that perceived interruptions predict state positive affect via responsiveness to these online messages and perceived task accomplishment. A daily survey study with 174 employees (a total of 811 day‐level observations) provided support for our hypotheses at the between‐person and within‐person level. In addition, perceived interruptions showed a negative direct association with perceived task accomplishment. Our study highlights the importance of being responsive to online messages and shows that addressing only the negative effects of perceived interruptions does not suffice to understand the full impact of interruptions by online messages in modern jobs. 相似文献