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871.
Coastal communities experience a wide array of environmental and social changes to which they must constantly adapt. Further, a community's perception of change and risk has significant implications for a community's willingness and ability to adapt to both current and future changes. As part of a larger study focusing on the adaptive capacity of communities on the Andaman Coast of Thailand, we used Photovoice to open a dialogue with communities about changes in the marine environment and in coastal communities. This article presents the results of two exploratory Photovoice processes and discusses prospects for using the Photovoice method for exploring social and environmental change. Changes examined included a number of broader environmental and social trends as well as ecological specifics and social particularities in each site. Participants also explored the social implications of environmental changes, the impacts of macro-scale processes on local outcomes, and emotive and active responses of individuals and communities to change. Photovoice is deemed a powerful method for: examining social, environmental, and socio-ecological change, triangulating to confirm the results of other scientific methods, revealing novel ecological interactions, and providing input into community processes focusing on natural resource management, community development, and climate change adaptation.  相似文献   
872.
阐述了张家界市森林病虫害的发生特点、森防工作面临的问题,并提出了强化森防工作的建议.  相似文献   
873.
本文试图从森林承载力的主要影响因素入手,通过人均消耗木材、薪柴、水果、干果等四个反映不同生活水平的指标,分析山东省沿海防护林体系的森林生产力及其与人口、经济社会发展的相关关系,预测山东沿海防护林体系不同时期、不同生活水平条件下的森林承载力,并探讨提高森林承载力的对策途径。  相似文献   
874.
湖北省具有发展森林资源的良好条件,但目前的森林覆盖率不高,林种结构不合理,森林生产力相当低。应在保护和经营好现有森林资源的基础上,以扩大森林面积和提高森林质量为中心,统筹规划,合理布局,增加投入,加速发展,科学经营,永续利用,不断提高其经济、社会、生态效益,造福于人民。  相似文献   
875.
The dissolved and particulate trace metals in large and middle-sized Chinese rivers remain comparable with other less-disturbed world systems. Levels of nutrients in Chinese rivers are high due to erosion over the drainage area and the application of chemical fertilizers, which induces an N/P ratio up to 100–1,000. The concentrations of organic pollutants in Chinese rivers are ranked at the lower end of those of world systems; however, pollution has been identified in coastal waters from north to south of the country. In estuarine and coastal waters, dissolved trace metals illustrate a feature of remobilization, while non-conservative distribution is observed, with exceptions for iron and aluminum. Particulate trace metals demonstrate a fairly stable distribution along the salinity gradient, when the absolute concentration is normalized to reference materials. In high-turbidity estuaries, seaward nutrient flux can be increased by a factor of 5–10. Finally, the N/P ratio approaches 10–20 at the interior of the East China Sea, indicating that in coastal regions photosynthesis changes from P to N and Si limitations. Electronic Publication  相似文献   
876.
Forests in and around the reserve located near the city of Chernogolovka (50 km northeast of Moscow), forests adjoining the city, and urban forests were examined during the period from 1992 to 2004. Differences between forests of the reserve proved to be less significant than those resulting from the impact of urban factors. The influence of a small city was found to change the structure of communities of small mammals in surrounding forests by reducing their diversity and enhancing the dominance of ecologically restrained synanthropic species.  相似文献   
877.
国家森林公园生态评价方法研究   总被引:4,自引:0,他引:4  
严山  周良 《环境导报》1998,(3):35-37
宝华山国家级森林公园是华东地区自然生态环境保存比较完好的北亚热带森林生态系统,通过建立多层次的生态评价指标体系,运用指标赋分和加权平均法,对宝华山林林公园进行评价。结果认为,该森林公园具有一定的代表意义和较高的保护开发价值。  相似文献   
878.
Coordinated soil–geobotanical studies revealed a close correlation between the species diversity of phytocenoses and soil properties in the Russkii Sever National Nature Park (Vologda oblast). Soil acidity, together with the concentrations of exchangeable calcium, potassium, and magnesium, is a factor determining variations of species diversity indices for vascular plants and bryophytes in forest biogeocenoses.  相似文献   
879.
Abstract:  Introducing rare plants to new sites for conservation to offset effects of habitat destruction requires detailed knowledge of habitat requirements, plant demography, and management needs. We conducted a factorial experiment replicated at three coastal prairie sites to test the effects of clipping frequency and litter accumulation on seed germination, seedling survival, reproduction, and seedling recruitment of introduced populations of the endangered, tall-stature, annual forb, Holocarpha macradenia (DC.) E. Greene. Clipping favored H. macradenia , primarily by enhancing seed germination and flower production. Litter accumulation had no effect on seed germination, even after 5 years of treatments. Seedling recruitment was highly site specific with large numbers of recruits recorded at only one of three sites. Although recruitment of seedlings was higher in clipped plots for 2–3 years, by 4–5 years after introduction very few seedlings survived to reproduction in any treatment. We attribute this result to a combination of poor habitat quality, small population size, and lack of a seed bank. We were unsuccessful in introducing this relatively well-studied species of concern to apparently suitable habitat at multiple sites in multiple years, which suggests that translocating rare plant populations to mitigate for habitat destruction is an expensive and highly uncertain endeavor.  相似文献   
880.
山区生态环境恶化原因及解决途径   总被引:1,自引:0,他引:1  
我国是个少林的国家,森林资源主要分布在东北、西南等地的山区,这些森林资源对于防止水土流失、保护生态环境起着非常重要的作用。然而,建国以后,我国山区的森林资源却遭到了很大破坏,山区生态环境也日趋恶化。本文即是从上述现实出发,分析了造成山区森林资源破坏和生态环境恶化的主要原因,探讨了怎样才能保护森林,保护好人类自己的家园。  相似文献   
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