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91.
浮游细菌群落对城市湖泊中的营养元素循环及有机质分解发挥着重要作用.基于高通量测序技术,对南昌市湖泊浮游细菌群落结构的时间(4、6和8月)和城郊差异及其影响因素进行了研究.结果表明:(1)南昌湖泊浮游细菌优势类群为放线菌门(Actinobacteria, 41.60%)、变形菌门(Proteobacteria, 22.29%)、蓝藻菌门(Cyanobacteria, 16.21%)和拟杆菌门(Bacteroidota, 10.17%).(2)南昌湖泊细菌群落结构在4、6和8月间存在显著差异,但在城区湖泊与郊区湖泊间不存在显著差异;以Proteobacteria(4月>6月>8月)和Cyanobacteria(6月>8月>4月)为主的10种菌门的丰度在3个月份间存在显著差异;6月菌群结构的相似性会随地理距离的增加产生明显的减小趋势,4月和8月的减小趋势不明显.(3)在降水偏多的6月,湖泊非淡水细菌的占比显著高于4月和8月,城区湖泊与郊区湖泊的非淡水细菌占比没有显著差异.(4)确定性过程主导了湖泊细菌群落的构建,随机过程对湖泊菌群构建的贡献较低;水温是影响南昌湖泊细菌...  相似文献   
92.
聂文东  刘学敏  张杰平  汪明  王若嘉 《灾害学》2011,26(1):133-137,143
通过对2009年11月12日在四川省广元市三堆镇马口村举行的自然灾害应急演练进行初步的分析研究,总结出了从前期准备、正式实施到演练评估的农村社区自然灾害应急演练基本流程和方法。在马口村自然灾害应急演练的前期准备阶段,根据当地实际情况选择了滑坡、泥石流为演练的自然灾害背景,制定了3级响应演练模式,并细化了各级响应的启动标准。在演练的正式实施阶段,采用了参与式的演练方案设计方法,充分调动了当地群众的积极性。演练结束后在现场发放调查问卷,对演练进行了多方面、多角度的评估,演练基本达到了预定目标。  相似文献   
93.
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   
94.
Trends in the diversity of structural organization of soil animal communities are analyzed using an example of the taxocenes of springtails, small soil arthropods. Different methods for describing the structure of communities are considered. On the basis of parameters characterizing specialization and stability of communities, several patterns of their organization in springtails are distinguished. It is shown that the new approach offers new opportunities in forecasting community dynamics under the effects of natural and anthropogenic factors.  相似文献   
95.
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   
96.
The structure of most forest communities in the European forest–steppe, including protected areas, has been disturbed. The adverse consequences of these disturbances include the incomplete age structure of the populations of cenosis-forming species and the irreversibility of successions. The conservation of biodiversity in the structurally disturbed communities is impossible without human intervention, which must be aimed at restoring their age heterogeneity with regard to their specific ecological features.  相似文献   
97.
This study provided information about the benthic insect communities that are present in the impacted reaches of Haggarty Creek.  相似文献   
98.
锡林郭勒盟不同草原类型植物群落多样性初步研究   总被引:1,自引:0,他引:1  
应用双指示种分析法TWINSPAN(Two-Way Indicators Species Analysis,TWINSPAN)和无偏对应分析DCA(Detrended Correspondence Analysis,DCA)对2005年7月中旬在锡林郭勒盟不同草原类型下采集的32个样方进行分类和排序处理。研究结果表明:1)研究区依据水分的差异包括3个不同草原类型(荒漠草原、典型草原、草甸草原),再依据热量和人为干扰的差异包括8个植物群落类型;2)草原植物群落多样性随荒漠草原-典型草原-草甸草原的变化而增加;在中度干扰下,草原植物群落比原生群落具有更高的多样性;不同草原类型过渡带的草原植物群落结构多样性比物种多样性明显。  相似文献   
99.
山东近海黄海段营养盐结构对初级生产力的影响研究   总被引:1,自引:1,他引:0  
于2006年8月(夏季)、2006年12月(冬季)、2007年4月(春季)、2007年10月(秋季)对山东近海黄海段的初级生产力和营养盐结构进行了调查.结果显示:(1)调查海域初级生产力的年平均值为438 mg/(m(2)·d),并呈现出"春季>夏季>秋季>冬季"的变化趋势;调查海区的营养盐结构表现出明显的季节分化:春...  相似文献   
100.
Solomon Islands is vulnerable to negative impacts from climate change, where people’s livelihoods and their well-being are threatened, especially the viability of isolated communities. Realising the increasing risks from climate change on communities, government, in partnership with aid-donor partners, has invested millions of dollars in climate change projects, through mitigation and adaptation strategies. As a form of adaptation, the government invests in programmes aimed at increasing the adaptive capacity of the vulnerable communities through landscape and seascape projects across the rural communities. Focusing on the “transformation concept” as a long-term adaptation strategy and enlargement of climate engineering and ecological resilience concepts, the paper discusses why building resilience from transformation of rural communities, as well as from landscape and seascape projects, would benefit communities and relevant authorities. This paper describes the findings of a study on two rural villages, Keigold and Mondo, from Ranogha Islands, Western Province, in Solomon Islands, where 80% of households decided to relocate from their old village “Mondo” to their new home “Keigold” after an earthquake in 2007, as part of a self-initiative. The reallocation process can be seen as a case of pro-active community transformation that provides valuable lessons to other rural communities that may be forced to move due to impacts from natural catastrophes, including those explained by climate change risks. Lessons from this experience suggest that policy-makers and non-government organisations should consider and empower local transformation initiatives as a way to building long-term adaptation to climate change.  相似文献   
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