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Adaptive capacity, one of the three determinants of vulnerability to climate change, is defined as the capacity of species to persist in their current location by coping with novel environmental conditions through acclimation and/or evolution. Although studies have identified indicators of adaptive capacity, few have assessed this capacity in a quantitative way that is comparable across tree species. Yet, such multispecies assessments are needed by forest management and conservation programs to refine vulnerability assessments and to guide the choice of adaptation measures. In this paper, we propose a framework to quantitatively evaluate five key components of tree adaptive capacity to climate change: individual adaptation through phenotypic plasticity, population phenotypic diversity as influenced by genetic diversity, genetic exchange within populations, genetic exchange between populations, and genetic exchange between species. For each component, we define the main mechanisms that underlie adaptive capacity and present associated metrics that can be used as indices. To illustrate the use of this framework, we evaluate the relative adaptive capacity of 26 northeastern North American tree species using values reported in the literature. Our results show adaptive capacity to be highly variable among species and between components of adaptive capacity, such that no one species ranks consistently across all components. On average, the conifer Picea glauca and the broadleaves Acer rubrum and A. saccharinum show the greatest adaptive capacity among the 26 species we documented, whereas the conifers Picea rubens and Thuja occidentalis, and the broadleaf Ostrya virginiana possess the lowest. We discuss limitations that arise when comparing adaptive capacity among species, including poor data availability and comparability issues in metrics derived from different methods or studies. The breadth of data required for such an assessment exemplifies the multidisciplinary nature of adaptive capacity and the necessity of continued cross‐collaboration to better anticipate the impacts of a changing climate.  相似文献   

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利用表型性状探讨了浙江省沿海地区20份南瓜地方品种资源的遗传多样性。结果表明,36个数量性状的变异系数在7.33%~59.11%之间,46个质量性状Shannon-wiener遗传多样性指数在0~1.99之间,表明其丰富的遗传多样性。农艺性状聚类分析表明,20份资源分为2大类,其中19份资源归为一大类;在欧氏距离15.0处把这一大类又分成5个小类,小类的划分与花萼片大小、花梗刺毛、瓜形、老瓜皮色等质量性状具有一定的相关性,但划分依据相对独立。本研究结果进一步丰富了南瓜的评价体系,并为今后优异基因资源的挖掘与利用提供了重要依据。  相似文献   

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贵州少数民族对作物种质资源的利用和保护   总被引:3,自引:0,他引:3       下载免费PDF全文
\"贵州农业生物资源调查\"项目属于国家科技基础工作重大专项。贵州属于云贵高原区,地形地貌复杂,气候多样,加之多民族聚集,有\"十里不同天,一山不同族\"的说法。正因为如此,贵州产生了丰富多样的农业生物资源。然而,世上的事物没有一成不变的,随着社会经济的发展,外来文化的渗透,贵州少数民族传统文化和生活习俗及与之相关的农业生物资源亦逐渐消失。国家为了保护少数民族传统文化和农业生物资源,特设立本调查项目,对贵州省42个县(市)进行了普查,并对其中21个县(市)进行了系统调查。本文仅介绍贵州少数民族对其相关的主要作物种质资源的利用和保护情况,旨在为国家保护少数民族传统文化、制定农业生物资源保护策略和科学研究提供基础数据和依据。  相似文献   

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贵州姑菁野生茶树形态多样性及相关性研究   总被引:3,自引:0,他引:3       下载免费PDF全文
以贵州省毕节市纳雍县姑菁村周边的野生茶树为研究对象,对其叶、花及果等34个表型性状进行统计分析,结果表明:21个描述型性状中有10个仅表现为1种表型,具有相对稳定的植物学性状,其他11个表现出不同程度的遗传分化。在数值型性状方面,变异系数在3.74%~21.86%之间,平均为15.10%;多样性指数在0.15~2.02之间,平均为1.62;基于数值型性状的聚类分析可把样本聚为3类,其中第Ⅱ、Ⅲ类均仅有3个样本,说明在后续进行农艺性状和品质性状鉴定以及对该资源保护与利用时应对该类的样株加以区分和重点关注;在环境影响方面,叶器官与果器官受到不同程度的海拔因素影响,表现出极显著相关以及分海拔区段间的差异性。姑菁野生茶树资源表型多样性丰富,后代遗传变异水平较高,具有较高的育种潜力。  相似文献   

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Yam is an important edible tuber and root plant worldwide; China as one of the native places of yams has many diverse local resources. The goal of this study was to clarify the genetic diversity of the commonly cultivated yam landraces and the genetic relationship between the main yam species in China. In this study, 26 phenotypic traits of 112 yam accessions from 21 provinces in China were evaluated, and 24 simple sequence repeat (SSR) and 29 sequence‐related amplified polymorphism (SRAP) markers were used for the genetic diversity analysis. Phenotypic traits revealed that Dioscorea opposita had the highest genetic diversity, followed by D. alata, D. persimilis, D. fordii, and D. esculenta. Among the 26 phenotypic traits, the Shannon diversity indexes of leaf shape, petiole color, and stem color were high, and the range in the variation of tuber‐related traits in the underground part was higher than that in the aboveground part. All accessions were divided into six groups by phenotypic trait clustering, which was also supported by principal component analysis (PCA). Molecular marker analysis showed that SSR and SRAP markers had good amplification effects and could effectively and accurately evaluate the genetic variation of yam. The unweighted pair‐group method with arithmetic means analysis based on SSR‐SRAP marker data showed that the 112 accessions were also divided into six groups, similar to the phenotypic trait results. The results of PCA and population structure analysis based on SSR‐SRAP data also produced similar results. In addition, the analysis of the origin and genetic relationship of yam indicated that the species D. opposita may have originated from China. These results demonstrate the genetic diversity and distinctness among the widely cultivated species of Chinese yam and provide a theoretical reference for the classification, breeding, germplasm innovation, utilization, and variety protection of Chinese yam resources.  相似文献   

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A wide diversity of domesticated chicken breeds exist due to artificial selection on the basis of human interests. Miniature variants (bantams) are eminently illustrative of the large changes from ancestral junglefowls. In this report, the genetic characterization of seven Japanese miniature chicken breeds and varieties, together with institute-kept Red Junglefowl, was conducted by means of typing 40 microsatellites located on 21 autosomes. We drew focus to genetic differentiation between the miniature chicken breeds and Red Junglefowl in particular. A total of 305 alleles were identified: 27 of these alleles (8.9%) were unique to the Red Junglefowl with high frequencies (>20%). Significantly high genetic differences ( F ST) were obtained between Red Junglefowl and all other breeds with a range of 0.3901–0.5128. Individual clustering (constructed from combinations of the proportion of shared alleles and the neighbour-joining method) indicated high genetic divergence among breeds including Red Junglefowl. There were also individual assignments on the basis of the Bayesian and distance-based approaches. The microsatellite differences in the miniature chicken breeds compared to the presumed wild ancestor reflected the phenotypic diversity among them, indicating that each of these miniature chicken breeds is a unique gene pool.  相似文献   

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为揭示滇龙胆天然居群表型变异程度和变异规律,以云南省5个区域天然分布的20个野生居群400个单株20个表型性状指标为调查研究对象,并用变异系数、Shannon-Weiner多样性指数和巢式方差分析对滇龙胆居群间和居群内的表型变异进行分析,用相关性分析对滇龙胆表型性状与地理气象因子间的变异格局进行分析,用类平均聚类法对20个滇龙胆居群进行分类.结果表明:5个区域的滇龙胆以楚雄地区变异最大,变异系数为39.8%,变异最小的是昆明地区,为31.4%;不同居群的20个表型性状变异程度差异明显,变异系数在14.4%~91.8%之间,平均为40.4%,20个居群的平均变异为26.8%~37.0%;滇龙胆地理居群的表型分化较高,20个性状居群间的分化系数平均为73.14%,变化范围为36.03%~91.94%,居群间变异高于居群内;滇龙胆20个表型性状的总的多样性指数平均为2.547,5个不同分布区域多样性指数存在差异,最大为楚雄(1.271 4),最小为玉溪(1.266 7);表型性状变异受经度和降雨量影响较大,与纬度、海拔和温度相关性不显著;通过UPGMA聚类,滇龙胆被分成3个组,性状的表型特征并没有依地理距离而聚类....  相似文献   

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内蒙古3种生态型扁蓿豆遗传多样性与亲缘关系的分析   总被引:1,自引:0,他引:1  
采用SSR分子标记结合21个表型性状对来自内蒙古3种生态型扁蓿豆种质资源的遗传多样性和亲缘关系进行了分析.结果表明:3种生态型的22份扁蓿豆材料在考察的4个质量性状上差异明显;在17个数量性状上,总体变异程度为黄花型扁蓿豆>扁蓿豆>细叶扁蓿豆;表型性状的遗传相似系数在31.59~113.27间,变异系数为43.30%.SSR分析结果显示,18对引物平均多态性比率为80.09%,引物平均等位位点数为6.06,位点多态性信息含量平均为0.32,遗传相似系数在0.37~0.47间,变异系数为61.80%.表型性状聚类、SSR分子标记聚类及主成分分析结果均显示,黄花型扁蓿豆和扁蓿豆的亲缘关系较近,与细叶扁蓿豆的亲缘关系较远.  相似文献   

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灯盏花种质资源群体表型多样性研究   总被引:10,自引:2,他引:10       下载免费PDF全文
以采集自云南和贵州的21份灯盏花种质资源为材料,观测了它们的群体表型性状特征,并分析了这些表型性状的遗传多样性.结果表明:灯盏花种质资源的表型质量性状在居群内外均有丰富变异,不同质量性状的频率不同,并以多叶型的植株、绿色的茎、疏的茎毛、倒披针型的基生叶、全缘叶、锐尖的叶尖、花色淡紫和黄色的管状花冠口等为代表性表型性状.居群内各数量性状间以单株基生叶数和单株分枝数变异系数较高(均超过50%),而花序直径变异系数最低(18.14%);居群间各表型性状以株高和单序管状花数变异系数较高(52.98%和41.98%),而单株基生叶数和基生叶长变异系数较低(<20%).地理类群间表型分化系数为26.58%,地理类群内表型分化系数为73.42%.灯盏花性状表型多样性指数以株高最高(2.243),以单株分枝数和单株基生叶数较低(1.723和1.874),总体平均表型多样性指数为2.028;不同地理类群的表型多样性指数为1.589~1.890,并以楚雄地区最高,曲靖地区最低.研究发现,灯盏花种质资源具有丰富的质量和数量性状变异,多数性状的地理类群内变异大于地理类群间,且表型多样性指数相对较高,对其地理类群内变异的保护和利用对灯盏花育种具有重要的意义.  相似文献   

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广西普通野生稻(Oryza rufipogon Griff)表型性状和SSR多样性研究   总被引:15,自引:0,他引:15  
以中国普通野生稻初级核心种质中广西普通野生稻部分中的 2 2 3份野生稻为材料 ,以平均分布于水稻 12条染色体上的 34对SSR引物和中国稻种资源目录中的表型性状分析广西普通野生稻SSR位点的等位变异、多样性的地理分布及不同生长习性间的多样性分布等。结果表明 ,每对引物检测到的多态性片段 7~ 4 8条 ,平均为 2 4 .91条 ,普通野生稻的等位变异数明显大于地方稻种 ,在所分析的SSR位点中杂合位点比例变化在 1.35 %~ 81.31%之间 ,平均为 32 .0 1% ,与自花授粉的栽培稻相比具有较高的杂合率 ;北纬 2 2°~ 2 3°和 2 3°~ 2 4°范围内的两个区域内(一个包括隆安、扶绥和邕宁三县 ,另一个包括象州、来宾、武宣、玉林和贵港五个县 )所包含的普通野生稻数量多 ,遗传多样性大 ,在DNA水平上是广西普通野生稻的遗传多样性中心 ,而表型性状多样性中心是在北纬 2 1°~ 2 2°和2 2°~ 2 3°,其多样性分布与DNA水平不完全一致。在 4种生长习性间 ,DNA水平上的遗传多样性大小依次为匍匐型 ,倾斜型 ,半直立型和直立型 ,表型水平的多样性与DNA水平的多样性基本一致。  相似文献   

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山西五鹿山森林群落木本植物功能多样性   总被引:1,自引:9,他引:1       下载免费PDF全文
薛倩妮  闫明  毕润成 《生态学报》2015,35(21):7023-7032
通过选取群落中木本植物种子的扩散方式、传粉方式、植株高度和盖度等13个功能性状,计算出群落的6个功能多样性指数:功能性状距离、功能性状平均距离、功能体积、功能均匀度、功能分散指数和Rao二次熵指数,结合群落物种丰富度指数、Shannon-Wiener指数和物种均匀度指数对山西五鹿山森林群落木本植物功能多样性进行研究。结果表明:(1)功能性状距离、功能性状平均距离、功能体积与物种丰富度、Shannon-Wiener指数显著正相关;功能均匀度与Shannon-Wiener指数、物种均匀度指数显著正相关;功能分散指数、Rao二次熵指数与物种均匀度指数、Shannon-Wiener指数显著正相关;(2)功能多样性的差异很大程度上是由于物种差异所引起的;(3)6个功能多样性指数可分为三类:功能性状距离、功能性状平均距离、功能体积为功能丰富度指数;功能均匀度为功能均匀度指数;功能分散指数和Rao二次熵指数为功能离散度指数。该分类结果符合指数的计算方法和生态学意义,以及相互独立的标准。  相似文献   

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The analysis of functional diversity (FD) has gained increasing importance due to its generality and utility in ecology. In particular, patterns in the spatial distribution and temporal change of FD are being used to predict locations and functional groups that are immediately vulnerable to global changes. A major impediment to the accurate measurement of FD is the pervasiveness of missing data in trait datasets. While such prevalent data gaps can engender misleading inferences in FD analyses, we currently lack any practical guide to handle missing data in trait datasets. Here, we identify significant mismatches between true FD and values derived from datasets that contain missing data. We demonstrate that imputing missing data with a phylogeny‐informed approach reduces the risk of misinterpretation of FD patterns, and provides baseline information against which central questions in ecology can be evaluated.  相似文献   

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泥炭地生态系统功能很大程度上取决于群落中物种功能性状的变化,但目前的相关研究仍非常有限。研究对大兴安岭4个地区的灌丛-莎草泥炭地植物地上-地下部分开展调查和取样,系统分析了植物比叶面积,比根长,比根面积,叶片和根系碳、氮和磷含量及生物量,研究了泥炭地植物的功能性状。通过计算群落加权平均值和功能离散度、Rao二次熵指数及相关变异系数,结合生物多样性指数,探讨泥炭地生物多样性、功能性状及功能多样性间相关性。结果表明:(1)灌木柴桦叶中的氮、磷含量显著高于白毛羊胡子草,且柴桦比叶面积变异系数较高;(2)灌木细根比根长和比根面积显著小于莎草,但细根氮和磷含量显著高于莎草。而且,灌木叶片和细根生物量显著高于莎草;(3)功能离散度和Rao二次熵指数较低,且其变异系数高于生物多样性和群落加权平均值各指数的变异系数;(4)灌木与莎草表现出地上-地下性状相关性上的差异,灌木根长与根面积显著正相关,莎草叶片和根系碳、氮和磷含量分别表现出了显著正相关,而功能离散度和Rao二次熵指数与生物多样性各指数相关性呈现一致性,其存在较强的耦合关系。研究结果表明,大兴安岭泥炭地物种间对资源竞争较大,灌木更适应泥炭地贫营养的环境。  相似文献   

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四川省珙桐天然种群叶表型多样性   总被引:1,自引:0,他引:1  
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In chimpanzees (Pan troglodytes), high-ranking males are expected to have high reproductive success and females typically emigrate upon reaching maturity. Although high average relatedness among males in the same social groups has been assumed, previous reports have indicated that relatedness among males is not necessarily significantly higher than that among females. The paternity of 11 offspring and the relatedness of 50 individuals in the M group of chimpanzees at Mahale Mountains National Park, Tanzania, were investigated using DNA analyses. We determined the fathers of 10 offspring. Two different alpha males sired a total of five offspring, whereas the other males had low reproductive success. The proportion of paternal half-sibling pairs among the 10 offspring was 15.6%. The average relatedness among mature males was significantly higher than that among mature females. The existence of an old male and the long tenure of one alpha male may have contributed to this significant difference. The average dyadic relatedness among mature natal individuals was significantly higher than that in natal-immigrant pairs in which the individuals came from different groups. The average relatedness among immigrant females was similar to that in pairs of natal and immigrant females, suggesting that the immigrants came from various groups. Thus, female transfer acts to maintain low average relatedness within the group. A comparison of our results to those from other study sites suggests that although the average relatedness among adult males does not reach the level of half-siblings, under some circumstances it can exceed the relatedness of females.  相似文献   

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为有效评价和利用蔗茅种质资源,挖掘其优良性状,以滇、黔、川考察收集的29份蔗茅为材料,选取5个数量性状为指标,对其多样性指数、变异系数、数量性状之间的相关性、数量性状与经纬度、海拔的相关性进行研究。分析结果表明:(1)共采集到25份高海拔种质资源,其中海拔超过2800米有4份,进一步丰富了甘蔗野生种质资源库;(2)蔗茅种质资源数量性状的Shannon-Wiener多样性指数均较高,株高多样性指数最高(1.441),锤度多样性指数最低(1.291);数量性状遗传变异较丰富,各性状变异系数范围为21%~38%,变异系数最大的为株高(38%),最小的为叶长(21%);(3)蔗茅种质资源性状差异显著,叶长、叶宽、株高、茎径存在较大相关性,而与锤度不相关;叶宽与经度呈正相关,与纬度、海拔呈负相关。(4)聚类分析结果表明,蔗茅种质资源可分为四大类群,其中Ⅱ类群(EF-27)具有良好的数量性状和锤度品质潜力,可推荐作为甘蔗育种杂交利用首选材料。  相似文献   

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为有效评价和利用蔗茅种质资源,挖掘其优良性状,以滇、黔、川考察收集的29份蔗茅为材料,选取5个数量性状为指标,对其多样性指数、变异系数、数量性状之间的相关性,数量性状与经纬度、海拔的相关性进行研究。分析结果表明:(1)共采集到25份高海拔种质资源,其中海拔超过2800m的有4份,进一步丰富了甘蔗野生种质资源库;(2)蔗茅种质资源数量性状的Shannon-Wiener多样性指数均较高,其中株高的最高为1.441,锤度的最低为1.291;数量性状遗传变异较丰富,各性状变异系数范围为21%~38%,变异系数最大的为株高(38%),最小的为叶长(21%);(3)蔗茅种质资源性状差异显著,叶长、叶宽、株高、茎径存在较大相关性,而与锤度不相关;叶宽与经度呈正相关,与纬度、海拔呈负相关。(4)聚类分析结果表明,蔗茅种质资源可分为4大类群,其中第Ⅱ类群(EF-27)具有良好的数量性状和锤度品质潜力,可推荐作为甘蔗育种杂交利用首选材料。  相似文献   

20.
The association between population dynamics and genetic variability is of fundamental importance for both evolutionary and conservation biology. We combined long-term population monitoring and molecular genetic data from 123 offspring and their parents at 28 microsatellite loci to investigate changes in genetic diversity over 14 cohorts in a small and relatively isolated population of mountain goats (Oreamnos americanus) during a period of demographic increase. Offspring heterozygosity decreased while parental genetic similarity and inbreeding coefficients (F(IS) ) increased over the study period (1995-2008). Immigrants introduced three novel alleles into the population and matings between residents and immigrants produced more heterozygous offspring than local crosses, suggesting that immigration can increase population genetic variability. The population experienced genetic drift over the study period, reflected by a reduced allelic richness over time and an 'isolation-by-time' pattern of genetic structure. The temporal decline of individual genetic diversity despite increasing population size probably resulted from a combination of genetic drift due to small effective population size, inbreeding and insufficient counterbalancing by immigration. This study highlights the importance of long-term genetic monitoring to understand how demographic processes influence temporal changes of genetic diversity in long-lived organisms.  相似文献   

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