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181.
Effects of acidification on aquatic ecosystems are analyzed on the basis of an analytical synopsis of relevant data. Major active agents influencing aquatic organisms and main trends in the reorganization of microbial, phyto- and zooplanktonic, benthic, and fish communities in an acidified environment are described. A generalized concept of changes in ecosystems caused by acid precipitation and accompanying factors is formulated. These changes include the reduction of biodiversity of all structural elements due to the disappearance of species sensitive to acidification, modification of trophic structure, and decrease of fish stock.Translated from Ekologiya, No. 2, 2005, pp. 110–119.Original Russian Text Copyright © 2005 by Moiseenko.  相似文献   
182.
The influence of recreation activity on grass cover was studied in a herbaceous birch forest within a territory of city development. Effects of the activity depended on size and arrangement of recreation sites. It was found that most of the forest was at the second stage of degradation, while degradation of forest edges was considered as intermediate between the second and third stages. Forest edges and glade-clump communities play a particular role in maintaining the stability of recreational forests.These ecotones are both barriers preventing introduction of alien plant species into a cenosis and centers of dissemination of ruderal and meadow species.  相似文献   
183.
This study examines the perspectives of Sami community members and university researchers regarding the ethical considerations for engagement in Community-Based Participatory Research (CBPR) with Sami communities in northern Finland. Key informant interviews were conducted with Sami people from Finland who were exposed to or participated in research in their communities as well as with researchers who have conducted research with the Sami in Finland across diverse topics. Five themes were identified: establishing trust, research preparation, research comprehension, research ethics, and inclusion in research. The differences in participant perspectives were compared based on their community versus researcher roles. Our findings emphasize the need for (1) strategies to develop and maintain trust between Sami communities and researchers; (2) methods to bridge concepts of bias projected onto Sami communities and researchers by the others’ differing world views and beliefs about research; and (3) increased education in community-engaged methods for social and natural scientists working with Sami communities. This study supports the need for the development of formalized ethical protocols for conducting community-based engaged research with and for Sami people in Finland that ensure mutually beneficial research for all involved.  相似文献   
184.
Abstract:  For many regions worldwide, multiple and often contrasting biogeographic classifications exist that are derived from a variety of taxa and techniques. This presents a challenge for managers who must choose appropriate large-scale spatial frameworks for systematic conservation planning. We demonstrate how systematically collected community data can be used to evaluate existing biogeographic classifications, identify the most appropriate metric for biogeographic patterns seen in other taxonomic groups, and develop an independent biogeographic classification scheme for systematic conservation planning. We evaluated 6 existing biogeographic classifications for New Zealand's nearshore marine environment with community-similarity metrics derived from abundance and presence–absence data for macroalgae (107 species) and mobile macroinvertebrates (44 species). The concordance between community metrics and the previous classifications was high, as indicated by a high multivariate classification success (CS) (74.3–98.3%). Subsequently, we carried out an independent classification analysis on each community metric to identify biogeographic units within a hierarchical spatial framework. The classification derived from macroalgal presence–absence data achieved the highest CS and could be used as a mesoscale classification scheme in which 11 regional groupings (i.e., bioregions) (CS = 73.8–84.8%) are nested within northern and southern biogeographic provinces (CS = 90.3–98.7%). These techniques can be used in systematic conservation planning to inform the design of representative and comprehensive networks of marine protected areas through evaluation of the current coverage of marine reserves in each bioregion. Currently, 0.22% of the territorial sea around mainland New Zealand is protected in no-take marine protected areas in which 0–1.5% of each bioregion represented.  相似文献   
185.
Participatory research has not been a conspicuous methodology in developing nations for studying invasive pests, an increasing threat to the sustainable development in the tropics. Our study presents a community-based monitoring system that focuses on three invasive potato tuber moth species (PTM). The monitoring was developed and implemented by young farmers in a remote mountainous area of Ecuador. Local participants collected data from the PTM invasion front, which revealed clear connection between the abundance of one of the species (Tecia solanivora) and the remoteness to the main market place. This suggests that mechanisms structuring invasive populations at the invasion front are different from those occurring in areas invaded for longer period. Participatory monitoring with local people may serve as a cost-effective early warning system to detect and control incipient invasive pest species in countries where the daily management of biological resources is largely in the hands of poor rural people.  相似文献   
186.
As a result of monitoring spatial changes in the cenotic structure of plant communities at the taiga-extrazonal steppe boundary on the western coast of Lake Baikal, models of taiga-steppe communities reflecting the formation, dynamics, and genesis of forests in the taiga zone have been constructed. Changes in the species composition of communities, mesophytization of steppes, the expansion of moss synusiae characteristic of polydominant dark conifer and light conifer taiga forests, active forest invasion into steppe areas, and the presence of dark conifer tree species in light conifer forests have been revealed.  相似文献   
187.
On the basis of abundant fossil and subfossil bone remains, the ecological and faunal role of the narrow-skulled vole in zonal rodent communities of northern Eurasia is analyzed over the period from the Late Pleistocene to the present time. Special attention is given to the correlated dynamics of relative abundance of Microtus gregalis and other rodent species in the course of transition from one zonal type to another and to specific features of this correlation in the southern, middle, and northern parts of the species range. It is shown that distinctive dimensional and morphotypic features of the two currently existing subspecies, Microtus gregalis major Ogn. and M. g. gregalis Pall., are the product of concordant development of the species and environmental conditions in the past 3000–4000 years (transition from the Holocene optimum to the present-day climate and state of the natural environment). Published in Russian in Ekologiya, 2007, Vol. 38, No. 2, pp. 117–123. The article was translated by the authors.  相似文献   
188.
利用磷脂脂肪酸(PLFAs)生物标记法分析野生型牵牛花(Pharbitis nil (Linn.) Choisy)根际土壤微生物群落结构,探讨牵牛花生长对石油烃污染土壤微生物群落与石油烃降解的影响.结果表明,供试土壤微生物群落中,先后出现了24种PLFAs,包括标记细菌的饱和脂肪酸(SAT)、革兰氏阳性菌(G+)的末端支链饱和脂肪酸(TBSAT)、革兰氏阴性菌(G-)的单不饱和脂肪酸(MONO)和环丙脂肪酸(CYCLO)、真菌的多不饱和脂肪酸(PUFA)和放线菌的中间型支链饱和脂肪酸(MBSAT)等六大类型.PLFAs的主成分分析(PCA)表明,牵牛花根际与对照组(未种牵牛花,CK)土壤微生物群落具有明显的差异,微生物多样性在春季增加83%、夏季增加140%、秋季增加50%;微生物的生物量在春季增加97.6%,夏季增加116.3%,秋季增加60.3%.牵牛花根际与对照组相比土壤中石油烃降解率明显提高,在春、夏、秋季分别提高了7.5%、34.2%和19.7%;并且,在牵牛花生长的不同季节石油烃的降解率有明显的差异,春季为22.3%,夏季为51.8%,秋季为38.0%.相关性分析表明,石油烃降解与土壤微生物总生物量具有中等程度的相关性(|r|=0.75);与G+细菌、甲烷氧化菌的生物量具有高度相关性,相关系数|r|>0.8;与G-的生物量具有中度相关性,相关系数为|r|=0.74;与真菌的生物量具有低度相关性,相关系数为|r|=0.36,与放线菌没有相关性,相关系数为|r|<0.30.  相似文献   
189.
Ecological literacy is founded upon knowledge and understanding about how the ecological systems of the Earth function and support life. A widespread concern that levels of ecological literacy within many contemporary human communities are inadequate to enable effective decision-making about sustainable ways of living led to a rigorous and carefully designed assessment of over 1000 South Australian adults from diverse sectors including industry, government, nongovernment, business and community organisations. This assessment tested for local and global knowledge, including an understanding of the interconnection of natural systems with human society. Quantitative analyses revealed significant relationships between scores and a range of socio-demographic characteristics. Scores varied significantly with gender, age, education, employment, place of growing up and time spent in South Australia (SA). Highest average scores were found in males, middle-age groups, the most highly educated, those with science-related educational backgrounds, those working in environment-related fields, those who grew up in small town environments rather than in large towns or cities and in those who had spent more than 10 years in SA. These findings contribute to a broader study of factors associated with ecologically literate individuals and groups within the western and industrialised adult community of SA. They form a valuable foundation on which to build efforts to further understand and develop ecological literacy within our citizenry and governing bodies.  相似文献   
190.
ABSTRACT

This article draws from the author’s four-year study of five school communities hit by the 2010–2011 earthquake sequence in the Canterbury region of New Zealand to highlight the roles that schools played in supporting their communities in the aftermath of the disaster. The article begins by synthesising the relevant literature on disasters, schools in earthquake disasters, and the importance of schools to their communities, pre- and post-disaster. The following themes from the data are discussed: (a) the role of schools in their communities prior to the earthquakes; (b) the role of schools in immediate rescue and response; (c) the role of schools in short-term relief; and (d) the role of schools in long-term recovery. The author then argues that as more evidence shows that schools play such crucial roles in post-disaster response and recovery, we need to better prepare and support them to undertake these functions. Further, we need to recognise the wider roles schools play supporting local communities to build and sustain resilience as part of on-going community cohesion and connectedness, so that society is better prepared when major disasters occur.  相似文献   
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