880 resultados para Plant genetic structure


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The Quaternary cold periods in the Northwestern Pacific are thought to have heavily influenced the amount and distribution of intraspecific genetic variation in marine fishes. To estimate the demographic history and genetic structure of Lateolabrax macula

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The decipherment of the meager information provided by short fragments of ancient mitochondrial DNA (mtDNA) is notoriously difficult but is regarded as a most promising way toward reconstructing the past from the genetic perspective. By haplogroup-specific hypervariable segment (HVS) motif search and matching or near-matching with available modem data sets, most of the ancient mtDNAs can be tentatively assigned to haplogroups, which are often subcontinent specific. Further typing for mtDNA haplogroup-diagnostic coding region polymorphisms, however, is indispensable for establishing the geographic/genetic affinities of ancient samples with less ambiguity. In the present study, we sequenced a fragment (similar to 982 bp) of the mtDNA control region in 76 Han individuals from Taian, Shandong, China, and we combined these data with previously reported samples from Zibo and Qingdao, Shandong. The reanalysis of two previously published ancient mtDNA population data sets from Linzi (same province) then indicates that the ancient populations had features in common with the modem populations from south China rather than any specific affinity to the European mtDNA pool. Our results highlight that ancient mtDNA data obtained under different sampling schemes and subject to potential contamination can easily create the impression of drastic spatiotemporal changes in the genetic structure of a regional population during the past few thousand years if inappropriate methods of data analysis are employed.

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Background: China, with around 30 unique breeds, has a diverse duck genetic pool. Currently, there is no systematic report which investigates the genetic diversity, phylogenetic relationship, and matrilineal genetic structure of these domestic breeds and

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Schizothorax o'connori is endemic to the Yarlung Tsangpo River on the Tibetan Plateau. We assessed the relative impacts of historical and contemporary factors in organizing genetic variation in S. o'connori populations using mitochondrial cytochrome b sequences. We analyzed 191 samples from 11 populations and identified 78 haplotypes. The phylogenetic analyses and analysis of molecular variance all supported the same conclusions of two well-differentiated east-west phylogroups, separated by the Tsangpo Great Gorge. The split between the two clades accounted for 58% of the genetic variance observed among the examined samples. Waterfalls as effective barriers played an important role in shaping the phylogeographical structure of this species. Analyses of migration rates revealed that upstream dispersal was limited crossing waterfalls. Our study revealed substantial spatial and temporal variation in the influence of landscape features on contemporary patterns of genetic structure in S. o'connori. Interglacial range expansions clearly left their mark on contemporary populations above the Tsangpo Great Gorge.

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We investigated the age and growth of Schizothorax o'connori in the Yarlung Tsangpo River by examination of annuli from otoliths. The von Bertalanffy model was the most acceptable statistical growth model. Its parameters were as follows: SL infinity = 492.4 mm, K = 0.1133, t(0) = -0.5432 year and W-infinity = 1748.9 g for females; SL infinity = 449.0 mm, K = 0.1260, t(0) = -0.4746 year and W-infinity = 1287.0 g for males. Theoretical longevity was 25.9 years for the female and 23.3 years for the male. Moreover, females had larger asymptotic length and weight compared with males.

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在浏览国内外大量文献的基础上,从土壤种子库研究意义、国内外研究现状和目前研究的热点问题等方面论述土壤种子库的研究进展。针对目前土壤种子库研究的热点问题,主要从土壤种子库的分类、种子质量和种子休眠之间的关系、种子库的水平分布及种子库与地上植被的关系等方面进行讨论,指出其在遗传结构和扩散等研究内容及方法方面所存在的问题,并提出了相应的建议。

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澜沧江姬鼠(Apodemus ilex)为小型啮齿类动物,长期以来常被认为是中华姬鼠(A. draco)或长尾姬鼠(A. orestes)的同物异名,但近年基于线粒体Cyt b 的研究证明,该类群与中华姬鼠的遗传距离达到了种间水平,并被认为是一个独立种。本文提取、扩增并测定了来自云南14个地区42个产地156个澜沧江姬鼠的Cyt b 全序列,并将GenBank中的3条澜沧江姬鼠的Cyt b 全序列纳入分析,选取福建武夷山与四川峨眉山的2个中华姬鼠样品的Cyt b 全序列,以及台湾姬鼠、大耳姬鼠、高山姬鼠Cyt b 全序列作为外群,利用贝叶斯法和最大似然法构建系统发育树,并使用Network分析,分子变异分析(AMOVA)分析、错配分析(Mismatch analysis)与Fu`Fs检验等方法,探讨了这些地区澜沧江姬鼠的种群遗传结构,种群动态及生物地理格局。结果表明:云南地区过去被鉴定为中华姬鼠的样品均属于澜沧江姬鼠,澜沧江姬鼠与中华姬鼠间的遗传距离(K2P-ds+v)达到0.091,显著超过姬鼠属内种间差距(0.080),支持澜沧江姬鼠独立种的地位;该种不同地理种群可大致以澜沧江为界分为两大支系,且每个支系又各分为两个亚支系;进一步的AMOVA分析表明遗传变异主要来源于两大支系之间,而错配分析与Fu`Fs检验表明澜沧江姬鼠各地理种群及其两个支系都经历过多次扩张事件,这可能是和冰期与间冰期的轮回交替有关;分子系统树和中介网络图表明地理环境的隔离对于澜沧江姬鼠种群分化存在明显影响,其中澜沧江的阻隔作用最为显著。基于松散分子钟(Relax molecular clock)分析,中华姬鼠和澜沧江姬鼠的分歧时间大约在2.98 Ma(95%HPD: 4.32-1.88),而澜沧江姬鼠则在1.13 Ma(95%HPD: 1.95-0.65)分成两个支系。按照平均分歧时间来看,澜沧江姬鼠两个支系的的分歧事件发生在鄱阳冰期(1.2-0.9 Ma),两个支系内部进一步分化为两支的时间非常接近,分别为:Clade 1中为0.67 Ma (95%HPD: 1.17-0.34)和Clade 2 中为0.64 Ma (95%HPD: 1.17-0.36),这种隔离种群各自产生分化的时间却非常接近,这提示其分化事件可能是受到古气候如冰期或间冰期的影响所产生。

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由于人类活动所引起的地球大气层中温室气体的富集已导致全球地表平均温度在20世纪升高了0.6 ℃,并预测在本世纪将上升1.4-5.8 ℃。气候变暖对陆地植物和生态系统影响深远,并已成为全球变化研究的重要议题。高海拔、高纬度地带的生态系统对气候变化最敏感。而在高原和高山极端环境影响下所形成的高寒草甸生态系统极其脆弱,对由于温室效应引起的全球气候变化极其敏感,对这些变化的响应更具有超前性。 本研究以川西北高寒草甸植物群落及几种主要物种为研究对象,采用国际山地综合研究中心(ITEX)普遍所采用的增温方法-----开顶式生长室(OTC)模拟气候变暖来研究增温对高寒草甸植物群落结构、物质分配及其主要物种生长和生理的影响,以探讨高寒草甸植物响应与适应气候变暖的生物学和生态学机制。主要研究结论如下: 1、OTC的增温效果 由于地温、地表温度和气温的平均值在OTC内分别高出对照样地0.28℃、0.46℃和1.4℃,这说明本研究所采用的开顶式生长室(OTC)起到了增温的作用;同时,由于温室内与温室外接受的降水量相同,温室内由于热量条件的改善,土壤蒸发和植被的蒸腾作用增强,直接导致了OTC内土壤表层相对湿度的减少。 2、群落结构对增温的响应 由于增温时间较短,增温内外样地的物种组成并未发生改变;但增温后一定程度上改变了植物群落的小气候环境,从而导致物种间的竞争关系被破坏,种间竞争关系的破坏引起群落优势种组成发生相应的改变,在对照样地,鹅绒委陵菜、甘青老鹳草、遏蓝菜和蚤缀是占绝对优势的物种,而在OTC内,小米草、尼泊尔酸模、垂穗披碱草、发草和羊茅的重要性显著增加。 禾草和杂草由于对增温的生物学特性及其资源利用响应的不同,加之增温造成土壤含水量下降等环境因子的改变。与对照样地相比较,OTC内禾草的盖度及生物量都显著增加,而杂草的盖度和生物量则显著下降。 3、植物生长期对增温的响应 OTC内立枯和调落物的生物量在生长季末(10月份)都要小于对照样地的立枯和调落物生物量,而OTC内的地上鲜体生物量在10月份却略高于对照样地。这说明OTC内植物的衰老或死亡得以延缓,而植物的生长期得以延长。 4、群落生物量及分配对增温的响应 OTC内的地上鲜体生物量(10月份除外)和地下0-30cm的根系生物量与对照样地相比较,都出现了不同程度的减少;土壤根系的分配格局也发生了明显的改变,其中,OTC内0-10cm土层的生物量分配比例增加,而20-30cm土层生物量分配比例的减少。 5、群落碳、氮对增温的响应 增温后,OTC内植物群落地上活体和地下活根的碳浓度不同程度的高于对照样地,植物群落的碳库在OTC内也略高于对照样地;而OTC内植物群落地上活体和地下活根的氮浓度不同程度的低于对照样地,其植物群落的氮库与对照样地相比也略有下降。 6、几种主要植物的生长及物质分配对增温的响应 垂穗披碱草在增温后株高、比叶面积和地上生物量均显著地增加;尼泊尔酸模在增温后比叶面积和单株平均生物量积累显著地增加,而各组分中,增温处理使叶的生物量显著增加,而根的生物量却显著下降;鹅绒委陵菜在增温后株高、比叶面积和单株平均生物量积累显著地减少,而各组分中,增温处理使叶和茎的生物量显著减少,根的生物量却显著地增加。 尼泊尔酸模的LMR、RMR、R/S、根部碳含量、碳和氮在叶片与根部的分配比例在增温后显著地增加,而SMR、根部氮含量、碳和氮在茎部的分配比例在增温后却显著地降低;鹅绒委陵菜的RMR、R/S、碳和氮在根部的分配比例在增温后显著地增加,而SMR、LMR、碳在叶片的分配比例在增温后却显著地降低 7、几种主要植物的光合生理过程对增温的响应 增温使垂穗披碱草和尼泊尔酸模叶片中的叶绿素a、叶绿素b、总叶绿素含量显著增加;而鹅绒委陵菜叶片的叶绿素a、叶绿素b、总叶绿素含量在增温后显著减少,类胡萝卜素含量在增温后却显著增加。 增温对3种植物的气体交换产生了显著影响。其中,垂穗披碱草和尼泊尔酸模叶片的光响应曲线在增温后明显高于对照处理,A、E、gs、Pmax、、Rday、AQY和LSP显著增加,而LCP则显著降低;鹅绒委陵菜的光响应曲线在增温后则明显的低于对照处理,A、E、gs、Pmax、、Rday、AQY和LSP显著减少,而LCP则显著增加。 增温后垂穗披碱草和尼泊尔酸模叶片的Fv/Fm、Yield和qP显著增加;而鹅绒委陵菜叶片的Fv/Fm、Yield和qP则显著减少,qN却显著地增加。 8、几种主要植物的抗氧化酶系统对增温的响应 增温使垂穗披碱草和尼泊尔酸模体内抗氧化酶活性和非酶促作用有所提高,植物膜脂过氧化作用降低;鹅绒委陵菜叶片中酶促反应和非酶促反应在增温后也显著提高,但可能由于增温后的土壤干旱超过了鹅绒委陵菜叶的抗氧化保护能力,抗氧化酶活性及非酶促反应(脯氨酸、类胡萝卜素)的提高不足以完全清除干旱诱导形成的过量活性氧,因此叶片的膜脂过氧化程度仍然显著提高。 Enrichment of atmospheric greenhouse gases resulted from human activities such as fossil fuel burning and deforestation has increased global mean temperature by 0.6 ℃ in the 20th century and is predicted to increase in this century by 1.4-5.8 ℃. The global warming will have profound, long-term impacts on terrestrial plants and ecosystems. The ecoologcial consequences arising from global warming have also become the very important issuses of global change research. The terrestrial habitats of high-elevation and high-latitude ecosystems are regarded as the most sensitive to changing climate. The alpine meadow ecosystme, which resulted from the composite effects of mountain extreme climatic factors in Tibetan Plateau, is thus thought to be especially vulnerable and sensitive to global warming. In this paper, the response of plant community and several main species in the alpine meadow of Northewst Sichuan to experimemtal warming was studied by using open-top chambers (OTC). The aim of the this study was to research the warming effects on plant community structure, substance allocation, growth and physiological processes of several mian species, and to explore the biological and ecological mechanism of how the alpine meadow plants acclimate and adapt to future global warming. The results were as follows: 1. Warming effects of OTC The mean soil temperature, soil surface temperature and air temperature in OTC manipulation increased by 0.28℃、0.46℃ and 1.4℃ compared to the control during the growing season. This suggested that the OTC used in our study had increased temperature there. Meanwhile, the OTC manipulation slightly altered thermal conditions, but the same amount of precipitation was supplied to both the OTC manipulation and the control, so higher soil evaporation and plant transpiration in OTC manipulation directly lead to the decrease of soil surface water content. 2. The reponse of community structure to experimental warming The species richness was not changed by the short-term effect of OTC manipulation. However, experimental warming changed the microenvironment of plant community, therefore competitive balances among species were shift, leading to changes in species dominance. In the present study, the dominant plant species in the control plots were some forbs including Potentilla anserine, Geranium pylzowianum, Thlaspi arvense and Arenaria serpyllifolia, however, the importance value of some gramineous grasses including Elymus nutans, Deschampsia caespitosa, Festuca ovina, and some forbs including Euphrasia tatarica and Rumex acetosa significantly increased in OTC. The different biology characteristics and resource utilizations between gramineous grasses and forbs, and enhanced temperature caused change in some environment factors such as soil water content. As a result, the coverage and biomass of gramineous grasses significantly increased in OTC compared to the control, however, the coverage and biomass of forbs singnifciantly decreased in OTC compared to the control. 3. The reponse of plant growing season to experimental warming Both the standing dead and fallen litter biomass in OTC were lower than those in the control in October, and the biomass of aboveground live-vegetation in OTC was higher than that of the control. The results indicated that the senescence of plants was postponed, and the growing season was prolonged in our research. 4. The reponse of community biomass accumulation and its allocation to experimental warming Experimental warming caused the decrease of aboveground live biomass and belowground root biomass except for the aboveground live biomass in October. Experimental warming also had pronounced effects on the pattern of root biomass allocation. In the present study, the root biomass in 0-10cm soil layer increased in OTC manipulation compared to the control, however, the root biomass in the 20-30cm soil layer decreased in OTC manipulation compared to the control. 5. The reponse of community C and N content to experimental warming The C concentration and stock in aboveground live and belowground root both increased in OTC manipulation compared to the control. However, the N concentration and stock in aboveground live and belowground root both decreased in OTC manipulation compared to the control. 6. The reponse of gowth and biomass, C and N alloction of several species to experimental warming Experimental warming significantly increased the height, SLA (specific leaf area) and aboveground biomass of Elymus nutans in OTC manipulation compared to the control. The SLA and total biomass of Rumex acetosa also significantly increased in OTC manipulation compared to control, among the different components of Rumex acetosa, leaf biomass significantly increased, but root biomass significantly decreased in OTC manipulation compared to the control. However, the height, SLA and total biomass of Potentilla anserina significantly decreased in OTC manipulation compared to the control, among the different component of Potentilla anserina, leaf and stem biomass significantly decreased, but root biomass significantly increased in OTC manipulation compared to the control. The LMR (leaf mass ratio), RMR (root mass ratio), R/S (shoot/root biomass ration) and root C concentration of Rumex acetosa significantly increased in OTC manipulation compared to outside control, also, Rumex acetosa allocated relatively more C and N content to leaf and root in response to experimental warming, however, the SMR (stem mass ration) and root N concentration of Rumex acetosa significantly decreased in OTC manipulation compared to outside control, also, Rumex acetosa allocated relatively less C and N content to stem in response to experimental warming. The RMR and R/S of Potentilla anserina significantly increased in OTC manipulation compared to outside control, also, Potentilla anserina allocated relatively more C and N content to root in response to experimental warming, however, the SMR and LMR of Potentilla anserina significantly decreased in OTC manipulation compared to outside control, also, Potentilla anserina allocated relatively less C and N content to leaf in response to experimental warming. 7. The reponse of physiological processes of several species to experimental warming Experimental warming significantly increased chlorophyll a, chlorophyll b and total chlorophyll of Elymus nutans and Rumex acetosa in OTC manipulation compared to outside control. However, chlorophyll a, chlorophyll b, total chlorophyll and carotenoid of Potentilla anserina in OTC manipulation significantly decreased compared to outside control. Experimental warming had pronounced effects on gas exchange of Elymus nutans, Rumex acetosa and Potentilla anserine. In the present study, warming markedly increased the light response curves of Elymus nutans and Rumex acetosa in OTC manipulation compared to outside control, and also singnificantly increased A (net photosynthesis rate), E (transpiration rate), gs (stomatal conductance), Pmax (maximum net photosynthetic rate), Rday (dark respiration rate), AQY (apparent quantum yield) and LSP (light saturation point), but LCP (photosynthetic light compensation) of Elymus nutans and Rumex acetosa in OTC manipulation singnificantly decreased compared to outside control. However, warming markedly decreased the light response curves of Potentilla anserina in OTC manipulation compared to outside control, and also singnificantly decreased A, E, gs, Pmax, Rday, AQY and LSP, but LCP of Potentilla anserina in OTC manipulation singnificantly increased compared to outside control. Experimental warming singnificantly increased the chlorophyll fluorescence kinetics parameters such as Fv/Fm, Yield and qP of Elymus nutans and Rumex acetosa and qN of Potentilla anserina in OTC manipulation, but Fv/Fm, Yield and qP of Potentilla anserina in OTC manipulation singnificantly decreased. 8. The reponse of antioxidative systems of several species to experimental warming Experimental warming tended to increase the activities of antioxidative enzymes and stimulate the role of non-enzymes of Elymus nutans and Rumex acetosa. As a result, MDA content of Elymus nutans and Rumex acetosa decreased. The activities of antioxidative enzymes and non-enzymes of Potentilla anserina also significantly increased in OTC manipulation, but more O2- was produced because of lower soil water content, and the O2- accumulation exceeded the defense ability of antioxidative systems and non-enzymes fuctions. As a result, MDA content of Potentilla anserine still increased in OTC manipulation compared to outside control.

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青杨作为一个本土树种,能较好的适应潮湿和寒冷的环境,对中国西部的人工造林有着重要的参考价值。在本实验中,选取7个中国西南地区分布的自然群体,用ISSR(inter-simple sequence repeats)作为分子标记研究其遗传多样性水平和遗传结构。通过筛选的8个ISSR引物,获得了158条清晰可重复的DNA条带,其中有156条具有多样性(占98.7%)。平均的Nei’s遗传多样性(h)为0.331;遗传分化系数(GST)为0.477,这表明有47.7%的遗传多样性发生在群体间。这种高水平的分化可能是由于当地复杂多变的地形和气候特点阻碍了基因流而引起的。此外在这7个青杨群体中,遗传距离和地理距离并未体现出有显著相关性(r=0.3122, P>0.05)。联合遗传距离和地理距离分析,鉴定出两处低水平基因交流的地区, 探讨其遗传障碍形成原因。 As a native species to China, Populus cathayana Rehd is well-adapted to the wet and cold environments where it occurs. It is considered to be an important reforestation species in western China. In the present study, we surveyed the level of genetic variation and the pattern of genetic structure in seven natural populations of P. cathayana, originating from the southeastern Qinghai-Tibetan Plateau of China, by using ISSR (inter-simple sequence repeats) markers. Based on eight primers, 158 clear and reproducible DNA fragments were generated, of which 156 (98.7%) were polymorphic. The average value of Nei's gene diversity (h) equaled 0.331. The coefficient of genetic differentiation (GST) equaled 0.477, which means that 47.7% of the total molecular variance existed among populations. Such a high level of divergence present among populations may be caused by the complex topography and variable climatic conditions present in the southeastern Qinghai-Tibetan Plateau which effectively restrict gene flow. Moreover, there is a lack of significant association between genetic and geographical distances (r=0.3122, P>0.05) in the populations of P. cathayana. The application of a novel method, which combines geographical coordinates and genetic differentiation to detect barriers for gene flow, allowed us to identify two zones of lowered gene flow.

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青杨(Populus cathayana Rehd.)是青杨派杨树的主要树种之一,为我国特有乡土树种,其主要分布区之一是我国的青藏高原,集中分布地带在甘肃省中部及青海省东部,四川省西北部岷江上游和松潘等地区。本研究以青藏高原东缘青杨天然分布区的6个群体143个个体为材料,用AFLP、SSR和叶绿体SSR分子标记分析青杨天然群体的遗传多样性,分析其遗传结构和分化,比较6个群体间遗传多样性的高低和群体间的遗传关系。旨在为青杨基因资源评价、保护与保存、遗传改良策略制定等提供科学理论依据。通过以上研究,得出如下主要研究结果: 1 AFLP分子标记研究结果 采用4对选择性引物对6个青杨天然群体143个个体进行分析,扩增谱带分析共检测到175个位点,其中173个位点表现为多态,多态位点百分率高达98.9%。从整体上表现出较高的遗传多样性,Nei’s基因多样度(h)水平为0.306。从青杨天然群体位点分布来看,有高达20%的位点(32位点)为群体所特有,仅有9.14%的位点(16位点)在所有群体中存在。群体间的遗传分化极大,所有遗传变异中,有48.9%的遗传变异存在于群体间。在个体群丛(Individuals cluster)和主坐标(PCO analysis)分析中,青杨各群体未呈现任何地理模式,Mantel检测也显示各群体间遗传距离与地理距离无明显相关。研究认为,由于地理和空间上大尺度的隔离和地形地貌复杂使得群体间无法进行基因交流,导致群体间遗传分化极大,另外各群体在不同的选择压力下,经历各自独立的进化历程,这些都可能导致群体间遗传距离与地理距离的不相关。 2 SSR分子标记研究结果 在SSR分析中,7个位点在6个青杨天然群体143个个体中共检测到79个等位基因,每位点检测到的等位基因数在5-16之间,平均11.3个,总体上多态位点百分率达100%。平均观察杂合度和期望杂合度分别为0.792和0.802。Hardy-Weinberg平衡检验表明青杨大部分群体都处于非平衡状态,群体大部分位点都是偏离哈迪-温伯格平衡(76.3%),只有23.7%的测验满足哈迪-温伯格平衡。分析青杨天然群体内和群体间的遗传变异,基因分化系数(GST)为0.373,即有62.7%的遗传变异存在群体内,37.3%的遗传变异存在群体间。群体内的遗传变异高于群体间水平。根据各群体遗传距离UPGMA聚类分析,有来自相临分布区、近似气候类型的群体聚在一起的趋势,但Mantel检测反映遗传距离与地理距离间并无明显相关性。 3 cpSSR分子标记研究结果 分析来自青藏高原东缘6个青杨天然群体,所用cpSSR引物中有5对cpSSR引物(CCMP2、CCMP5、SCUO01、SCU03、SCU07)都表现较高的多态性,单个引物检测的片段数都在4以上。5对cpSSR引物共检测片段数26个,组成了12种叶绿体DNA单倍型。各群体的单倍型分布和频率有较大差异,群体单倍型多样性范围为0-0.4926,TS、JZ、PW和SHY群体单倍型多样性高于QHY和LED群体水平。本研究发现,分布在青藏高原东缘的青杨天然群体,群体间不存在共享的单倍型,各群体间存在极大的遗传分化(GST=0.9223)。从青藏高原东缘地区经历的地质历史事件来看,第四纪的冰期气候变迁可能是造成青杨现今遗传结构模式的主要因素之一。根据单倍型在各群体的分布情况,进行青杨群体聚类分析结果,各群体无明显的分组现象,青杨各群体也未呈现任何清晰地理模式。 由于不同分子标记在对群体遗传多样性检测能力与效率上存在差异,所以三种标记检测的青藏高原东缘青杨天然群体遗传多性水平也不尽一致,但在与用同种方法检测其它物种或同一物种不同种源群体比较,三种分子标记方法都揭示了青藏高原东缘青杨天然群体具有中等偏上的遗传多样性水平。结果分析表明,群体间遗传分化极大,这是由于青杨天然群体分布于青藏高原东缘,既有高原又有高山峡谷,由于地理和空间上大尺度的隔离和地形地貌复杂导致了基因流物理上的阻隔。三种分子标记研究结果经Mantel分析检测,遗传距离与地理距离之间都无明显相关性。较为一致的解释是,青杨分布区域地理和空间上大尺度的隔离和和地形地貌复杂导致群体之间不存在均匀扩散现象,另外各群体在不同的选择压力下,经历各自独立的进化历程,这些都可能导致群体间遗传距离与地理距离的不相关。 The wide geographical and climatic distribution of P. cathayana Rehd. indicates that there is a large amount of genetic diversity available, which can be exploited for conservation, breeding programs and afforestation schemes. The results are as follows: 1 Research results of AFLP genetic diversity In present study, genetic diversity was evaluated in the natural populations of P. cathayana originating from southern and eastern edge of the Qinghai-Tibetan Plateau of China by means of AFLP markers. For four primer combinations, a total of 175 bands were obtained, of which 173 (98.9%) were polymorphic. Six natural populations of P. cathayana possessed different levels of genetic diversity, high level of genetic differentiation existed among populations (GST=0.489) of P. cathayana. Individuals cluster and PCO analysis based on Jaccard’s similarity coefficient also showed evident population genetic structure with high level population genetic differentiation. The long evolutionary process coupled with genetic drift within populations, rather than contemporary gene flow, are the major forces shaping genetic structure of P. cathayana populations. Moreover, there is no correspondence between geographical and genetic distances in the populations of P. cathayana, seldom gene exchange among populations and different selection pressures may be the causes. Our finding of different levels of genetic diversity within population and high level of genetic differentiation among populations provided promising condition for further breeding or conservation programs. 2 Research results of SSR genetic diversity In this study, the genetic diversity of P. cathayana was investigated using microsatellite markers. In a total of 150 individuals collected from six natural populations in the southeastern part of the Qinghai-Tibetan Plateau in China, a high level of microsatellite polymorphism was detected. At the seven investigated microsatellite loci, the number of alleles per locus ranged from 5 to 16, with a mean of 11.3, the observed heterozygosities across populations ranged from 0.408 to 0.986, with a mean of 0.792, and the expected heterozygosities across populations ranged from 0.511 to 0.891, with a mean of 0.802. The proportion of genetic differentiation among populations accounted for 37.3% of the whole genetic diversity. The presence of such a high level of genetic diversity could be attributed to the features of the species and the habitats where the sampled populations occur: The southeastern part of the Qinghai-Tibetan Plateau is regarded as the natural distribution and variation center of the genus Populus in China. Variation in environmental conditions and selection pressures in different populations, and topographic dispersal barriers could be factors associated with the high level of genetic differentiation found among populations. The populations possessed significant heterozygosity excesses, which may be due to extensive population mixing at the local scale. The cluster analysis showed that the populations are not strictly grouped according to their geographic distances but the habitat characteristics also influence the divergence pattern. In addition, we suggest that population SHY should be regarded as an ecologically divergent species of P. cathayana. 3 Research results of cpSSR genetic diversity Genetic diversity of six natural populations of P. cathayana originating from the southeastern part of the Qinghai-Tibetan Plateau in China was studied by use of cpSSR markers. Based on 5 pairs of polymorphic primers screened from 12 pairs of primers, twenty-six different length fragments and twelve different kinds of haplotypes were reduced in 143 samples. There were significant variant haplotypes among the populations.There were no shared haplotypes found among populations, analysis of molecular variance indicated that a high proportion of the total genetic variance was attributable to variations among populations (92.23%). The pattern of genetic structure which is associated with spatial separation, variation in environmental conditions and selection pressures in different populations, is also the result of geological historical factor. A molecular phylogenetic tree based on the 12 haplotypes showed that the populations are not strictly grouped according to their geographic distances.

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西南地区在我国的经济发展和生态环境建设中占重要地位,但也是我国生态环境最脆弱的地区之一,生态系统退化,生态功能减弱,严重制约着西南林业的可持续经营与发展。本项目采用DNA 分子标记SSR 研究不同生境条件下粗枝云杉群体的遗传变异及其时空分布格局,考察遗传变异与复杂的山地生态环境间的潜在联系,系统地揭示粗枝云杉天然群体与环境系统相互作用的生态适应与分子进化机制。粗枝云杉适应性强,生长迅速,在植树造林和工业用材方面占有重要地位,研究成果可为中国西南部亚高山天然林的可持续经营及退化生态系统的恢复与重建提供理论依据和科学指导。主要研究结果如下: 1. SSR 位点变异丰富,等位基因频率的分布格局多样。7 个SSR 标记全是多态位点,每位点的等位基因数变化范围为13~24,平均为19.9 个。SSR 位点的等位基因片段长度范围变化较大。73.1%的等位基因变异遵循逐步突变模型(SSM)而发生1 个重复基元的变化,22.3%和4.6%的变异分别按两阶段突变模型(TMP)发生1 个重复基元以上的变化和在SSR 位点侧翼区发生1 个碱基变化的插入-删除事件。 2. 粗枝云杉拥有中等偏高水平的遗传多样性和相对大的群体间遗传分化。通过分析代表10 个群体的250 个个体在7 个SSR位点的变化,调查了源自中国西南山区的粗枝云杉的微卫星变异。相当高的遗传多样性和强烈的群体分化发生在粗枝云杉中, 其群体平均Nei's 期望杂合度为0.707 , 群体间遗传距离为0.121~0.224(FST)和0.100~0.537(RST)。然而,群体间遗传距离与地理距离之间无相关性,从而排除了简单的距离分离模式并暗示迁移不是影响粗枝云杉遗传变异格局的主要因素。事实上,使用私有等位基因估算的基因流数量非常低,仅等于0.753。等位基因置换检验(Allele permutation tests)揭示逐步突变及遗传漂变都对群体间分化有贡献。另外,在多数位点检测到显著的群体间遗传差异,这个结果说明自然选择,假设通过环境压力,是引起粗枝云杉微地理分化的主要因素之一。根据SSR基因型,250 个粗枝云杉个体的70%被正确地归类入其各自的来源群体,结果表明微卫星(SSR)对区分来自中国不同生态地理位点的粗枝云杉基因型是有效的。 3. 在SSR、RAPD 和AFLP 位点,显著的群体间遗传结构被发现的,但三种标记间遗传分化程度和群体遗传关系有差异。利用来自10 个群体的247 个个体,我们报告了关于样本粗枝云杉群体间遗传关系的总体看法。根据各自对评价遗传关系的信息能力和适用性,SSR、RAPD 和AFLP 标记被选用,三种技术非常有效地区别这些基因型。使用的SSR、RAPD 和AFLP 标记分别估计平均Dice 相似性系数。Mantel 检验产生显著但相对低的共表型适合度(RAPD = 0.63£AFLP = 0.60和SSR = 0.75)。比较三种标记系统,RAPD 和AFLP 共表型指数相对高地相关(r =0.59),而RAPD 和SSR 及SSR 和AFLP 之间的相关系数分别是0.53 和0.35。所有系统树,包括不同标记资料结合获得的系统树,反映了多数群体依据它们的地理条件而成某种特定关系。结果暗示单个或结合标记系统能用来深入洞察粗枝云杉遗传研究,并且不同标记系统合并资料能提供更可靠的信息。 Southwestern region plays an important role in economic developmentand ecological construction in China. Yet, it is also one of the weak regionsof ecological environment in China with degraded ecosystem and imperfectfunction, which restricts the sustaining management and development ofsouthwestern forestry. The genetic variation and spatial distribution patternof P. asperata populations originating from different habitats wereinvestigated using SSR molecular markers in this study. The correlationsbetween genetic variation and ecological and environmental conditionswere detected, and the interaction between P. asperata populations andenvironmental system and the mechanism of ecological adaption -molecular evolution were revealed. Given the significant ecological andeconomic roles of the fast-growing and wide-adaptive species in reforestation and production of pulp wood and timber, the study couldprovide a strong theoretical evidence and scientific direction for thesustaining management of subalpine natural forest, and the afforestationand rehabilitation of degraded ecosystem. The results are as follows: 1. The genetic variation at SSR loci was abundant and the distributionof allelic frequencies was uneven. All seven loci were polymorphic, and thenumber of alleles per locus varied from 13 to 24 with a mean valueequaling 19.9. The allele sizes at SSR loci were found to vary widely.73.1% of allelic variation followed stepwise mutation model (SSM) whichresults increase or decrease by one repeat type, and 22.3% and 4.6% wereresulted from two-phase mutation model (TMP) with allele size varying bymore than one repeat type and from insertion-deletion events in theflanking regions at SSR loci with a single basepair changing, respectively. 2. P. asperata possessed a moderate to high level of genetic diversityand considerable genetic differentiation. Microsatellite variation of P.asperata. originating from the mountains of southwestern China wasinvestigated by analyzing variation at seven SSR loci in 250 individualsrepresenting ten populations. A fair degree of genetic diversity and strongpopulation subdivision occurred with the mean gene diversity (H) of 0.707,and genetic distances among populations varying between 0.121 and 0.224(FST) and between 0.100 and 0.537 (RST). However, inter-populationgenetic distances showed no correlation with geographic distances between the population sites. This ruled out a simple isolation by distance modeland suggested that migration does not have a great impact. In fact, theamount of gene flow, detected using private alleles, was very low, equalingonly 0.753. Allele permutation tests revealed that stepwise-like mutations,coupled with genetic drift, could contribute to population differentiation.Moreover, significant genetic differences between populations weredetected at most loci. The results indicate that natural selection, presumablythrough environmental stress, may be one of the main factors causingmicro-geographical differentiation in the genetic structure of P. asperata.Based on SSR genotypes, 70% of the 250 individuals were correctlyclassified into their sites of origin. This suggests that microsatellites (SSRs) are effective in distinguishing genotypes of P. asperata originating fromdiverse eco-geographical sites in China. 3. Using a set of 247 individuals from ten P. asperata populations wereport an overview on the genetic relationship among the sampled P.asperata populations. RAPD, AFLP and SSR were used in terms of theirinformativeness and applicability for evaluate relationship and all threetechniques discriminated the genotypes very effectively. Mean Dicesimilarities coefficient were estimated using RAPD, AFLP and SSR,respectively. The Mantel test resulted in a significant but relatively low fit(RAPD = 0.63, AFLP = 0.60 and SSR = 0.75) of cophenetic values.Comparing the three marker systems to each other, RAPD and AFLP cophenetic indices were highly correlated (r = 0.59), while correlationcoefficient between RAPD and SSR was r = 0.53 and between SSR andAFLP was r = 0.35. For all markers a relatively high similarity indendrogram topologies was obtained although some differences wereobserved. All the dendrograms, including that obtained by the combineduse of all the marker data, reflect some relationships for most of thepopulations according to their geographic conditions. The results indicatethat single or combined marker system could be used to insight into geneticstudy in P. asperata and the combined data of different marker systems canprovide more reliable information.

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青藏高原东南缘由于特殊的生态地理条件,有着丰富的森林资源,这些资源是长江上游涵养水源、保持水土的生态屏障,是生物多样性的资源宝库。但随着过量的森林采伐,使该区曾经丰富的生物多样性资源遭受了前所未有的破坏,天然林的质量严重下降,生态系统退化,功能减弱。与此同时,许多物种的种群规模正在锐减,物种的遗传多样性也严重丧失。川西云杉是西部地区分布最广的云杉树种之一,在较高海拔的地区有着重要的生态学功能,是一种适应性很强的乡土树种。本项目采用简单序列重复标记(SSR)和特定序列位点(STS)研究不同生境条件下川西云杉群体的遗传变异及其时空分布格局,考察遗传变异与复杂的山地生态环境间的潜在联系,系统地揭示川西云杉天然群体与环境系统相互作用的生态适应与分子进化机制。研究成果能有效地为该树种遗传资源的科学保护与合理利用提供理论依据和科学指导,可为中国西南部亚高山天然林的可持续经营及退化生态系统的恢复与重建提供依据。主要研究结果如下: 1 STS和SSR两种分子标记的研究结果表明:川西云杉群体拥有中等水平的遗传多样性(基于SSR标记,平均He = 0.640;基于STS标记,平均He = 0.553)。造成这种中等水平的遗传多样性,可能是由于历史原因,川西云杉天然林被大量采伐,导致了遗传多样性的丧失。两种方法都检测出群体BT有着最高水平的遗传多样性。 2 两种标记的结果都一致说明:检测的10个川西云杉群体间遗传分化比较高,其存在群体间的遗传变异比例要明显地高于广泛分布的挪威云杉、横贯大陆的黑云杉以及兼有连续分布和不连续分布的西加云杉等,但要低于分布范围狭窄且呈不连续分布的粗枝云杉。青藏高原东南部的片段化生境可能是导致高水平遗传分化的主要原因。 3 基于两种标记的UPGMA 聚类和PCA分析结果,以及基于SSR标记的FCA分析结果都显示:群体BY遗传上明显区别于其它群体,其可能原因是青藏高原东南缘山脉阻隔而导致的生殖隔离的结果。 4 根据软件Bottleneck 1.2.02的检测以及不依赖哈迪一温伯格平衡的M比率检测结果:川西云杉种群很有可能经历了近期的遗传瓶颈效应。在本研究中遗传瓶颈效应并没有显著影响到物种的遗传多样性。然而,在这些片断化群体未来的子代群体中很可能出现遗传瓶颈导致的遗传多样性下降的效应。 Due to the extremely complex topography and climatic conditions, the southeast of the Qinghai-Tibet Plateau is region abundant in forest resource, which is benefit to the upper reaches of the Yangtze River water conservation, and protecting natural environment and biodiversity resources. However, by the reason of a plenty of trees were cut in these yeas, the biodiversity resource was destroy with degraded ecosystem and imperfect funcation. Picea balfouriana is one of the regionally distributed conifer species in the southeast of the Qinghai-Tibet Plateau and considered as a constructive species within its distribution area. It is an optimal species for the production of biomass. Moreover, it is well adapted to stressful environments at high altitude, especially to cold and drought conditions which are generally harsh for other trees. In our study, two types of molecular markers (SSR and STS) were used to estimate the genetic diversity and genetic structure of P. balfouriana populations originating from the southeast of the Qinghai-Tibet Plateau with varying climatic and geographical conditions. The results will not only provide a deep insight into its genetic diversity and population genetic structure but also valuable information for further management and breeding programs in P. balfouriana. In summary, the results obtained in this study revealed that: 1 A moderate degree of genetic variation is present in P. balfouriana in the southeast of the Qinghai-Tibet Plateau and it may caused by many trees were cut in the past. Population BT owns the highest level of genetic diversity by both two types of markers. 2 Considerable population differentiation exists among the ten P. balfouriana populations based on both SSR and STS markers, possibly caused by habitat fragmentation and heterogeneous environments. 3 The UPGMA clustering and PCA analyses based on SSR and STS marker, and FCA analyses based on SSR marker congruously separated population BY from other populations, which is likely due to the presence of mountain barriers. 4 The results of bottleneck analysis indicated that P. balfouriana populations that have undergone recent declines. In our research, the bottleneck effect don’t have a significant impact on the genetic diversity of species, however, the level of genetic diversity of P. balfouriana offspring populations growing in the fragmented habitats will decline in the future.

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genetics, such as: population size, reproduction, mating system, growth, development,genetic structure and systematics status; The main results are presented below: The seasonal variation of the operational sexual ratio of this animal was found in the field and the ration always bias the female in the breeding season. Aiming at this character and considering the distance of time and space of both sexual habitat in breeding season, we census female population first by toe-clipping mark-recapture method, then estimated the population size with the definitive sexual ratio. Up to now, this species was found only at the Beilun district of the Ningbo City. The population size of the Ruiyan Temple Forest Park approximates to 369. The status of this population is extremely endangered, so besides protecting this population at the original locality, we also suggested to breed the salamander in fenced locality and to hatch embryos artificially, and send metamorphosed juveniles back to nature. We can transfer some individuals to other similar habitats or breed them under artificial conditions for saving this species from extinction. The early developmental stage of the Chinhai salamander is the same as its relative species, E. andersoni. Their balanceres are poorly developed and disappear very early. Temperature and moisture significantly influence the embryonic development of the Chinhai salamander. The embryonic stage is approx. 29 days under room temperature. The hatchling grows in a logarithmic curve. The larvae stage in water is approx. 58- 88 days. Many factors influence the nomal development, including two aspects of internal and external. Due to these factors, the effective protected measures were presented in detail. The breeding migration of E. chinhaiensis takes place at late March~late April every year. This salamander's hatching rate is high, but the rate of hatchling migrating into water is low. The average effectiveness of all the nest sites is 36.7%. The maternal self-conservation was contrary to the reproductive success of the egg-laying strategy. In the strategy of egg-laying behavior, the first factor selected by the female was its self-conservation, the second is embryonic survival rate, and the last is rate of hatchling survival rate. The oviposition selection is significant for the survival of the larvae. Based on the analysis of the evolutionary process of reproductive behaviors nad egg-laying site selections of all genera of the family Salamandridae, we deduced that perhaps Echinotriton is a transitional type in the evolutionary process from water to land. Due to its location in the adaptive stage in the terrestrial evolution, Echinotriton chinhaiensis's terrestrial nest may be one of important reason that causes this species to be endangered. The genetic deversity analysis shows that although the population size of the Chinhai salamander is quite small compared to other Chinese salamandrid species, the genetic diversity of this population is not reduce remarkably. We explain this phenomena with the polygamy mating system of this species. The result of 4 families' parenthood determinations shows that the parenhood determination can be taken without any paternal information. The "children" of every female include rich genetic information from at least two "fathers". It implies that female Chinhai salamander mates more than once with different males in a breeding season. The molecular evidence, the behavioral observation evidences and the sperm evidence in the female cloaca proved that this species has a polygamy mating system. The kin recognition in the mating of adult salamander was first discussed. The taxonomic status and phylogenetic relationships of 12 species representing 6 genera in the family Salamandridae were studied using DNA fingerprinting. The results showed that the DNA fingerprinting. The results showed that the DNA fingerprinting patterns demonstrated rich genetic diversity and species diversity, and also revealed the taxonomic status and phylogenetic relationshipes of higher taxa to a certain extent. The results are highly consistent with those obtained from the studies based on the morphology, ecology, cytology and molecular biology. The compreshensive analysis indicate that Tylototrition hainanensis and T. wenxianensis should be valid species; Echinotriton should be a valid genus;Tylotortriton is a natural cluster; Tylotortriton asperrimus should be put in Tylototrition rather than in Echinotriton, Hypselotriton and Allomestriton are synonyms of Cynops and Paramesotriton, respectively. There are three main groups in Chinese salamandride: Cynops, Paramesotriton and Pachytrition from the first group, the species of the Tylototriton from the second, and E. chinhaiensis composes the third.

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沙蜥属(Phrynocephalus)的卵胎生类群主要分布在我国青藏高原,包括南疆沙蜥(P. forsythii)、西藏沙蜥(P. theobaldi)、红尾沙蜥(P. erythrurus)、贵德沙蜥(P. putjatia)和青海沙蜥(P. vlangalii)。其卵胎生生殖方式适应了高寒生境,与青藏高原隆升有关。纵观前人的研究,上述几种卵胎生沙蜥的分类、系统发育关系以及生物地理都还存在疑问。本文研究了分布在若尔盖湿地的青海沙蜥红原亚种(P. v hongyuanensis)以及分布在黄河上游其它地区青海沙蜥种组的地理分布格局,并探讨了其形成机制。 青海沙蜥在黄河上游主要分布于若尔盖湿地以及青海湖周边地区。若尔盖湿地青海沙蜥红原亚种的生境由于沼泽的形成被切割成不连续的斑块,通过遗传分析可以推测这种特殊生境对它们遗传结构的影响。其次,贵德沙蜥、青海沙蜥的青海湖周边各居群以及若尔盖湿地居群之间的系统地理格局还未见报道。因此本文以居群为单位,将它们作为一个复合体,通过系统地理研究,可以了解其种群遗传结构,据此分析相关的地质历史事件对其分布的影响。主要结果如下: 1. 若尔盖湿地青海沙蜥红原亚种的种群遗传结构: 共研究了三个地理单元(红原(HY)、辖曼(XM)、玛曲(MQ))的7个采集点的72个个体。所有ND4-tRNALeu序列比对得到785 bp的片断,定义了9种单倍型。结果显示总的核苷酸多样性较低,单倍型多样性较高。分子变异分析(AMOVA)显示3个单元间差异显著(P<0.01),遗传变异主要存在于地理单元间,占62.61%。除MQ单元,XM各居群与HY居群混杂在一起,单倍型网络图没有显示出单倍型和地理位置的对应关系。XM单元单倍型的不配对分布(Mismatch distribution)为明显左移的单峰,且Fu’s Fs test为负值,表明XM单元可能经历了近期种群扩张,有足够的时间积累单倍型的多态性,还不足以大幅提高核苷酸多样性,这是其单倍型多样性较高和核苷酸多样性较低的原因。MQ单元遗传多样性低而与其他单元显著分化,推测这与3万年前黄河在若尔盖玛曲之间贯通有关。近期沼泽的形成对XMb居群的隔离时间短,使得其遗传多样性低但还不足以形成大的遗传差异。无论黄河的贯通还是沼泽的形成其隔离形成的时间都不长,其作用改变了单倍型出现的频率,也出现了一些特有单倍型,但共享单倍型还广泛存在,还不足以使得不同居群之间形成较大的遗传距离。 2. 黄河上游青海沙蜥种组的分布格局与地史过程的关系: 黄河上游青海沙蜥种组包括贵德沙蜥、青海沙蜥指名亚种的青海湖周边各居群、青海沙蜥红原亚种若尔盖湿地居群、以及青海湖以西的部分居群(序列由Genbank下载获得),总计22个居群189个样品。所有ND4-tRNALeu序列比对得到703个位点,定义了39种单倍型。以南疆沙蜥为外群构建的贝叶斯树以及MP法构建的无根树,都分为A、B两大组。其中A包括若尔盖湿地居群以及玛多居群(A1)、青海湖以西的居群和兴海居群(A2)、西藏沙蜥;B包括青海湖以南的居群和天祝居群(B1)、青海湖以东北的居群(B2)。单倍型网络图分别对应了系统发育树上的各支。按照系统发育结果分组进行分子变异分析,得到组间变异占88.63%,各组间差异显著(P=0.000)。种群遗传结构分析得到,A1和B2可能经历了近期的种群扩张,前者扩张时间约为0.105-0.189 Ma B.P.(million years before present),后者为0.057-0.102 Ma B.P.,可能与末次间冰期的气候变暖有关。A2和B1对应的两个地理单元都具有较强的种群遗传结构,较为稳定。 青海沙蜥种组A、B两大支之间遗传距离大,分化明显,分化大约发生在4.29-2.38 Ma B.P.,推测青藏运动的A幕运动后复杂的地形变化可能是它们产生分化的原因。B1和B2分化大约发生在1.73-0.96 Ma B.P.,这与湟水流域构造运动发生的时间相符。在早、中更新世时期,B1支内部各居群可能有交流,中更新世末共和盆地出现的抬升以及河流溯源改道等事件可能是引起这支内部多个单倍型丢失的原因。A1、A2支的分化可能与倒数第三次冰期降临之后气候变冷、阿尼玛卿山的大冰帽有关。 The viviparous group of genus Phrynocephalus is mainly distributed in the Qinghai –Tibetan Plateau, including P. forsythii、P. theobaldi、P. erythrurus、P. putjatia and P. vlangalii. These species are adapted well to the cold clime there, and the origin of this group was the result of a vicariance event associated with the uplifting of the Qinghai -Tibetan Plateau. Although many works have been done, there are still several questions about classification、phylogenetic relationships and the biogeography of this group. The phylogeographic pattern of the P. vlangalii complex on the upper reaches of the Yellow River and the P. v. hongyuanensis in Zoige Wetland were studied in this thesis. On the upper reaches of the Yellow River, P. vlangalii complex are distributed in Zoige Wetland and the southeast and northeast region of Kuku-noor Lake. Because of the forming of the wetland in Zoige, the habitats for sand lizards are divided into many discontinuous ones, and it is necessary to analyze genetic structure in these unique habitats. The phylogeographic patter among P. putjatia、populations of P. vlangalii in the southeast region of Kuku-noor Lake and populations of P. vlangalii in Zoige Wetland hasn’t been studied yet, and the complicated geological events of the Plateau may play an important role in the populations’ diversity and species forming there. So these populations were gathered as a complex, and phylogeographic analysis were used to clarify these doubts. According to the two topics above, this thesis has two parts of results as follows: 1. Three geographic units of P. vlangalii hongyuanensis in Zoige Wetland were defined, and they were Xiaman (XM)、Hongyuan (HY) and Maqu (MQ). 785bp fragments of the mtDNA ND4-tRNAleu were determined from 72 samples and nine haplotypes were identified. As a whole, the nucleotide diversity was low,but the haplotype diversity was high. Analysis of molecular variance (AMOVA) showed that the three units were distinctly different(P<0.01),and 62.61% of the total genetic diversity was attributable to variation among units. There were 3 haplotypes shared among XM and HY,and no geographic clustering was observed except MQ from the TCS network. The results from the mismatch distribution analysis and Fu’s Fs test implied that there might be a recent population expansion in the XM unit, and this may be the reason why XM had a high haplotype diversity but a low nucleotide diversity. We estimate that the MQ and XMb have lower diversities because of some very recent geographic events, such as the formation of the Yellow river’s upriver and the Zoige Wetland. Although they are distinctly different, not enough time has passed for them to have diverged a great genetic distance. 2. 189 samples in 22 populations of P. vlangalii complex were collected, including P. putjatia、populations of P. vlangalii in the southeast and northeast region of Kuku-noor Lake、 populations of P. vlangalii in Zoige Wetland and the data from Genbank. 703bp ND4-tRNALeu sequences identified 39 haplotypes. P. forsythii was selected as outgroup, and both the Bayesian tree and the MP unrooted tree were divided into two groups(A、B). A included populations in Zoige Wetland and Xinghai(A1)、populations in the west of Kuku-noor Lake(A2)、P. theobaldi, and B included populations in the southeast of Kuku-noor Lake and Tianzhu(B1)、populations in the northeast of Kuku-noor Lake(B2). The haplotype network agreed with these groups. AMOVA showed that these five groups were distinctly different(P<0.01), and 88.63% of the total genetic diversity was attributable to variation among groups. There might be recent population expansion in A1 and A2, which corresponded to the dry climate of the last interglacial period. The expansion times were 0.189-0.105 Ma B.P. and 0.102-0.057 Ma B.P., respectively. A2 and B1 had strong genetic structure. The large genetic distance between A and B showed that they had been separated from each other for a long time(about 4.29-2.38 Ma B.P.), and it corresponded to the A phase of Qingzang Movement. The diversity between B1 and B2 at 1.73-0.96 Ma B.P. may be caused by the geological event in Huangshui valley. In early Pleistocene, populations in B1 may have gene flow because of geographic linkage, and later the uplift of the Plateau and the change of river route there made a few haplotypes lost. A1 and A2 were divided into two parts by A’nyemaqen Mountains at 0.66-0.37 Ma B.P., which maybe corresponded to glaciations at about 0.7 Ma B.P.