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1.
Picea neoveitchii is an endemic species in China. It had been listed as an endangered species in red data books. It scatters in several locations of south slope of the Qinling Mountain of China. Upon reviewing the related literature, discussing with leading scholars on gymnosperm, ecology and plant conservation, the field survey was carried out in four locations. There are eleven mature individuals and two seedlings surviving in its natural habitats. With the survey of quadrat method in four locations, related community index were calculated such as relative important value (RIV), species richness, similarity index, diversity index and evenness index etc. The community could be sorted and characterized as three groups based on the community parameters. The analysis of vegetation table elucidates that Picea neoveitchii is a dominant species with low grouping rate in most surveyed sites. The RAPD analysis shows target species has intraspecific genetic variability. The estimation of Shannon's phenotypic diversity index (Ho) also explains the difference of genetic variations of different locations. Due to the lack of enough knowledge and professional guide of conservation biological perspective, Picea neoveitchii had been clear-cut for timber production. The extent of occurrence and area of occupancy declined rapidly from 1950s to 1990s. According to the Conservation Category guideline proposed by the World Conservation Union, the conservation status of Picea neoveitchii was reevaluated as Critically Endangered (CR) B2b C2a D. Upon research in areas of ecology, molecular biology, cluster analysis of environmental parameters, a practical conservation strategy is recommended in this research.  相似文献   

2.
昆虫在自然界中占据着多样性更高、空间尺度更小的生境,对生境的变化也更敏感,开展昆虫多样性与环境因子的相关性研究对生态环境监测和保护具有重要意义。实验中我们选用庐山风景区不同人工草坪进行研究,对它们昆虫群落及环境因子特征进行了随机取样调查,采用多样性指数和典范对应分析(CCA)研究昆虫群落与环境因子之间的相关性。实验共收集了昆虫11目,472头,以直翅目和鳞翅目占优势,其个体数分别占捕获昆虫总个体数的5324%和2278%。CCA分析表明:昆虫与环境因子之间的相关性高达100%,提示环境因子变化影响昆虫的分布,从研究结果看,践踏强度、样地大小、植被类型都对昆虫群落的分布影响很大。为该区域昆虫资源的保护和利用以及人工草坪的设置等相关研究提供科学依据  相似文献   

3.
Harvesting of non-timber forest products is an integral component of rural livelihoods throughout the developing world. At times this is at odds with conservation objectives. Reconciliation of the two requires examination of local level contexts and needs. This paper reports on the harvesting needs for Ischyrolepis by a rural community in South Africa, against the setting that they had recently been prohibited from harvesting by the local conservation officials. Interviews were conducted with conservation officials to understand the reasoning for the prohibition. Local demand for Ischyrolepis was assessed by household surveys, as well as in-depth interviews with traders. The density and size class distribution of Ischyrolepis was determined using transects. The total annual demand for Ischyrolepis was determined to be approximately only 2.7% of the standing crop. The bulk of the annual demand was for small-scale trade, the income from which was a primary source of income for the few harvesters. Very little evidence could be found indicating that harvesting was damaging the resource or its habitat, and local knowledge suggested that the abundance of the species was stimulated by harvesting. Even if market demand were to increase, the size of the shoots required means that less than 20% of the standing crop could be harvested annually. Current regulations around harvesting are in a state of revision, and hence confusion prevails regarding if harvesting is permissible, and if so, under what conditions, which is detrimental to both conservation and livelihoods. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   

4.
Fences are very common in rural areas, and represent important landscape elements in both tropical and temperate climate regions. In spite of their marked presence and importance, fences have been little studied, principally in Brazil. The present study examined the types of fences, the diversity of species used in their construction, as well as the diversity of their uses in a rural community in the municipality of Caruaru, Pernambuco State, northeastern Brazil. Fifty meters of fence-line in each of 50 rural properties in the community were examined, noting the diameter, height and identity of all vegetation elements used in their composition. Semi-structured interviews were also held with their builders in order to obtain information concerning fence uses. In the total of 2,500 linear meters of fence-line, 4,953 individual plant elements were identified, belonging to 51 different species. A majority of the fence elements were non-living fence posts, although the number of living posts was high. Of the total number of fence elements, 66.7% were native to the caatinga region. The large number of native species used as non-living fence posts indicates an intensive use of the caatinga vegetation and suggests the need to stimulate the use of living fence posts for conservation purposes.  相似文献   

5.
Chinese pine, Pinus tabulaeformis Carr., a species that ranges broadly across northeastern to southwestern China, plays a vital role in the maintenance of the structure and function of these ecosystems. In this study, we examined the genetic diversity of five widespread populations in Shanxi Plateau, the distribution center of Chinese pine, using 15 random amplified polymorphic DNA (RAPD) primers and five inter simple sequence repeat (ISSR) primers in 140 individual tree samples. Similar genetic differentiation results were obtained from the data of RAPD and ISSR. Based on the two sets of data, Nei’s genetic diversity was 0.2842 and 0.3078 and Shannon’s indices of diversity were 0.4332 and 0.4468. Genetic diversity at the species level was found high relative to that for other genera of Pinaceae. The greatest diversity was observed in the Lingkong Mountain population (0.3860), while the lowest was recorded in the Luya Mountain population (0.3352), most likely as a result of natural adaptation and anthropogenic perturbation. The relative magnitude of differentiation among populations (G ST) was 0.1491 and 0.1356, respectively, implying that most genetic variation was within the populations (∼0.8509), rather than among populations. Published in Russian in Ekologiya, 2008, No. 1, pp. 36–42. The article was translated by the authors.  相似文献   

6.
7.
In a meeting between FUNAI (the Brazilian Indian National Foundation) and the Kayapo in the Kayapo village of Aukre, in October 2005, the Kayapo Indians requested support to increase the culture of coconuts (Cocos nucifera) in their lands. The introduction of exotic species is a cause of biological diversity loss throughout the world. However, this is by no means applicable to all kinds of exotic species. We argue that the culture of coconuts may actually be a useful tool for the conservation of this country’s indigenous lands, despite criticism to the contrary. It may also be useful as source for raw material for the indigenous people who are presently experiencing a population boom. For the Kayapo of south-eastern Amazonia, such a demographic explosion, coupled with their increasing dependence on money to purchase industrialized goods, tend to substantially increase the pressure on their lands, which still contain a substantial amount of well-preserved seasonally-dry Amazonian forests. We investigated the actual economic relevance of coconuts for the Kayapo by measuring human and coconut populations and found that this exotic palm is not important for the subsistence of these Indians, due to coconut scarcity, and that such importance is not forthcoming. In the Amazon, coconuts may be particularly useful for the Indians’ nutrition due to the high energetic value of the solid endosperm of the mature fruit. Therefore, given the importance of indigenous lands for the conservation of the Amazonian forests, the encouragement of subsistence coconut cultures in indigenous lands is defensible as a measure for the conservation of biodiversity.  相似文献   

8.
为系统阐明长湖鱼类群落结构特征,2014年3~11月对长湖鱼类群落结构的空间差异和季节动态进行了较为全面的调查。结果表明,长湖共调查到鱼类43种,隶属于7目14科37属,主要为湖泊定居型鱼类;大湖区和海子湖区鱼类优势种组成虽存在一定的差异,但鲫、鰐、鲤和达氏鲌为两个湖区的共同优势种;长湖鱼类群落的Margalef丰富度指数、Shannon-Wiener多样性指数和Pielou均匀度指数分别为0.53~2.30、0.52~2.02和0.24~0.66,除丰富度指数外,均表现为5月或8月相对较高;聚类和MDS排序分析结果表明长湖鱼类群落分为两大类群,呈现显著的时空异质性;ABC曲线显示长湖优势鱼类以小型鱼类或大型鱼类的幼体为主,且已受到不同程度的干扰。针对长湖鱼类资源已出现衰退,建议在拆除围网/拦网养殖、取缔有害渔具的同时,考虑增殖放流、栽种水生植物等措施来达到长湖鱼类资源保护和可持续利用的目的。  相似文献   

9.
Forest vegetation of a community managed forest (Van Panchayat) located between 1570–1700 m elevation was studied along four aspects. Quercus leucotrichophora was the dominant species on three of the four aspects. Across the aspects the total tree density ranged between 150 and 490 ind/ha, sapling density between 100 and 370 ind/ha, seedling density varied from 241 to 1090 ind/ha. The shrub density ranged from 166 to 690 ind/ha and herb density from 6000–17100 ind/ha. The total basal area of tree layer varied from 9.78 to 13.5 m2/ha showing that the forest is young. Species diversity value for tree layer varied from 0.14 to 1.69. Quercus leucotrichophora were regenerating well due to effective forest management by local communities. The higher proportion of seedlings of Quercus leucotrichophora indicating that the Van Panchayat are playing important role in conservation of oak forest of Himalaya.  相似文献   

10.
Abstract

The coupling relation exists in water and soil conservation and economic-social development. The article analyses the relation of soil and water conservation and economic-social development stages as well as the coupling analytical method. Then calculates the expecting income by dispersing Markov decision and calculates the correlation coefficient and the relationship degree. The article obtains the relationship of soil and water conservation investments and all kinds of incomes. Finally, it analyzes the important meaning in socio-economic development of water and soil conservation.  相似文献   

11.
We compared differences in plant species diversity between conifer (Pinus tabulaeformis) plantations and natural secondary forests in the middle of the Loess plateau. The goal of the study was to examine the differences in the effect of stand development on species diversity and in species responses to changes between forest types and between forest layers. To clarify the effects of differences in forest management, we emphasized the functional types of plant species occurring in each forest type. The result as follow: (1) The H′ and S of tree layer were significantly lower in natural conifer forest than old conifer and secondary forest, but were not different compared with mid aged conifer forest. The H′ and S of shrub layer were significantly lower in mid aged conifer forest compared with other forest types. The H′ of herb layer showed no significant differences in the four forest types. The evenness index (J′) of tree layer of mid aged conifer forest was lower than other forest communities and its J′ of shrub layer was highest although its richness of shrub layer was lower than in the other forest types. (2) The analysis of β diversity index also indicated large differences between conifer plantations and natural forests. Although the tree layer species were similar in old plantation and natural conifer forests, they differed greatly between the natural conifer and secondary forests. The natural conifer and secondary forest species composition in shrub layer differed significantly from those in plantation and secondary plots. Tree species were significantly less common in plantations than in abandoned coppice forests. Species composition in the herb layer of different forest types was similar. (3) The management of P. tabulaeformis plantations alters plant species composition considerably; the number of sub tall-tree species is increased in old aged conifer forest, especially species dispersed by animals. Plantation management appears to affect ecological processes through seed dispersal. From the perspective of management, the change in the structure and composition of the canopy in plantations could affect the behavior of dispersers and regeneration.  相似文献   

12.
基于2013~2015年、2017~2018年长江中游监利江段的鱼类资源监测数据,采用多样性指数和多元统计方法分析该江段的鱼类群落结构特征。研究表明:5年共监测到鱼类68种,隶属于6目13科,其中鲤形目共46种;2018年监测的鱼类种类数要多于其他年份。各年份的均匀度指数值相差不大,2018年Shannon Wiener指数值和Margalef丰富度指数值要大于前面4个年份,优势度指数值有一定波动,但值均偏低。ABC曲线及W统计表明2013年和2014年鱼类群落结构受到了人类活动的严重扰动,而2015、2017和2018年受到人类活动的扰动程度不大。聚类分析和非度量多维尺度分析显示鱼类群落可以分为三组,但相似性分析表示三组间无明显差异。  相似文献   

13.
Water insecurity, induced or intensified due to climate change, has emerged as a key policy challenge in poor and developing countries such as India. Drawing on social cognitive theory, this paper examines the role of perceived collective efficacy—people's shared beliefs about their group's capabilities to accomplish collective tasks—and trust in government as factors influencing Indians' engagement with government water conservation policies. Using a national survey of Indians (N = 4031), we found that individuals with high levels of perceived collective efficacy and trust in government are more likely to support government water conservation policies. Moreover, for individuals with low trust in government, higher collective efficacy is associated with greater policy support. Perceived collective efficacy is also associated with activist behaviours, while distrust is not. Increasing collective efficacy beliefs, for example through mass media channels and targeted campaigns, could help increase citizens' engagement with climate change adaptation policies.  相似文献   

14.
三峡库区香溪河消落带植被多样性及分布格局研究   总被引:1,自引:0,他引:1  
研究三峡大坝蓄水10 a后香溪河消落带不同高程区域植被的物种组成、群落多样性及其空间分布特征,旨在为库区消落带生态修复中的物种选择、植被群落重建提供依据。研究结果发现:(1)香溪河消落带植被以一年生草本植物为主,物种组成比较简单。植物种群空间分布分析表明,优势种种群均属于聚集分布;(2)随着高程的增加,α多样性指数中Patrick丰富度、Shannon-wiener多样性和Pielou均匀度呈增加趋势,而Simpson优势度则与其它三个指数相反呈递减的趋势;而β多样性指数中Cody指数、Wilson-Shmida指数、Jaccard指数和Sorenson 指数均呈增加趋势;(3)推荐狗牙根、马唐、狗尾草和香附子4种植物作为三峡库区香溪河消落带植被恢复的备选草本物种。  相似文献   

15.
长江常熟江段近岸小型鱼类群落结构及多样性探析   总被引:2,自引:0,他引:2  
2009年3月~2010年2月,利用密目插网对长江常熟江段小型鱼类进行了连续监测,首次对该江段的小型鱼类群落组成、优势种组成及生物多样性进行了剖析。结果表明:该江段共有小型鱼类24种,隶属于5目7科,其中鲤形目最多。根据〖WTBX〗IRI〖WTBZ〗指数分析,贝氏〖FK(W1。1〗〖PS餐鱼1.eps〗〖FK)〗、刀鲚、窄体舌鳎、蛇鮈和光泽黄颡鱼为优势种,共占总数量的83.44%,占总重量的8202%;贝氏〖FK(W1。1〗〖PS餐鱼1.eps〗〖FK)〗和窄体舌鳎在各个季节中均为优势种,刀鲚在春、夏、秋3季为优势种。基于渔获数量的分析结果显示,常熟江段各月多样性特征值范围为:Shannon Wiener指数(H’) 118~176, Margalef指数(R)087 ~207,Pielou指数(J’)048~083,McNaughton指数(Dn) 057~086。Margalef指数和McNaughton指数春季最高,冬季最低;Shannon Wiener指数和Pielou指数冬季最高,夏季最低。最后探讨了影响该江段小型鱼类群落结构的各种因素,提出了合理开发和保护小型渔业资源的建议  相似文献   

16.

Climate change is projected to influence the genetic resources of plant species. Recent research has examined genetic diversity patterns under current climate conditions, with little attention to the future genetic consequences for species. In this study, we combined ecological niche modeling and population genetic approaches to project future changes in genetic diversity using plastid and nuclear DNA and reconstructed distribution patterns of three circumboreal plants (Chamaedaphne calyculata, Linnaea borealis ssp. borealis, and Pedicularis sceptrum-carolinum ssp. sceptrum-carolinum) in the last glacial maximum. We found that circumboreal plants could potentially lose their geographic ranges in the future (2070; 35–52% in RCP 4.5 (representative concentration pathways), 37–53% in RCP 6.0, and 56–69% in RCP 8.5), only slightly compensated by a predicted range gain of 18–33% (across the three RCPs). It is expected that future genetic diversity level could remain similar or lower than the present level. On the other hand, the homogeneity of the genetic background—a lack of admixture and domination of one gene pool in most populations of C. calyculata and L. borealis ssp. borealis—was predicted to become more pronounced in the future. Combining the paleoecological niche modeling and genetic data revealed, more precisely, the climate refugia for circumboreal plants in the Alps, central Asia, Beringia, and southern North America and the macrorefugia more restricted to the northern part of Eurasia and North America, reaching the arctic zone.

  相似文献   

17.
In the 35 years since its inception, the Brazilian National Program for the Conservation of Marine Turtles (TAMAR) has had great success in protecting the five species of sea turtles that occur in Brazil. It has also contributed significantly to worldwide scientific data and knowledge about these species’ biology, such as life cycles and migration patterns. TAMAR’s conservation strategies have always relied on a variety of environmental education and social inclusion (EESI) activities highly adapted to the socio-environmental evolving contexts of its 25 locations distributed across nine states. Diversity and flexibility are critical to enable timely and effective local responses to existing or potential threats to sea turtles. The intuitive, locally adapted, decentralized, and independent way EESI activities have been carried out have generated positive results in the resolution of specific and evolving local problems through the course of the project. This article brings EESI under the same conceptual framework that underlies its conservation approach by adopting an adaptive threat management framework to organize and qualify its educational and social inclusion interventions according to the main categories of threat addressed by TAMAR.  相似文献   

18.

Genetic polymorphism has been studied in populations of two annual xerohalophyte species of the family Chenopodiaceae, Atriplex tatarica and Sedobassia sedoides, growing on soils with different levels of soil moisture and sodium and potassium ion contents. A tendency toward decrease in the percentage of polymorphic loci in A. tatarica at higher soil salinity and increase in the observed heterozygosity of S. sedoides populations at higher levels of soil potassium has been revealed, with parameters of genetic variation in either species showing no dependence on soil moisture. Soil potassium deficiency is a stress factor for S. sedoides at both physiological and population-genetic levels. Mechanisms controlling sodium absorption and maintaining ion homeostasis and also a high level of homozygosity in S. sedoides indicate the improvement of stress tolerance in this annual species.

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19.
Davidova  R.  Vasilev  V.  Boycheva  M.  Bakalova  J.  Ali  N. 《Russian Journal of Ecology》2019,50(2):200-207

The dynamics of nest-dwelling mites from the nests of the great tit in the protected area of Kamchia Mountain in Northeastern Bulgaria was investigated. The mite fauna inhabiting the nests of great tit differs significantly in terms of the degree of infestation, species richness, abundance and structure of communities in study years. There are statistically significant differences in the specimens’ number between 2014 and the other years 2012, 2013 and 2015. The mite species such as Dermanyssus gallinae, Androlaelaps casalis and Ornithonyssus sylviarum demonstrated significant changes in the abundance over the study years. A relation between the abundance of a species and the species diversity in the nests was not registered. Comparison of the annual dynamics of mites in the nests of great tit and the nests of semi-collared flycatcher for the same period of time and for the same environment, showed similarities—a significant fluctuation in the abundance of mites over the years and differences—in the species richness. Regarding the structure of the communities, both similarities and differences were recorded.

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20.
Abstract

Spring water in the city of Jinan comes from the limestone areas. Understanding the capacity of wellspring conservation is a critical point to resume the perennial spewing of the spring water. The vegetation, soil, and other natural and human aspects related to the conservation are studied by using the methods of geographic information systems (GIS), remote sensing (RS), and field investigation. In the end, suggestions for administration and planning as well as countermeasures are put forward.  相似文献   

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