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资助项目
GST, P < 0.05) were exhibited by this species. The SAMOVA revealed seven diverging groups of related chlorotypes, six of them had distinct nonoverlapping geographical ranges: one in the northeast comprising 10 populations, a second with a southeast distribution comprising 22 populations, and the remaning four groups comprising 15 populations located in the west part of the species’ range along different river valleys. The genetic clustering of populations into three regions was also supported by analysis of molecular variance, which showed that most genetic variation (82.43%) was found among these three regions. Two clusters were distinguished by both phylogenetic analysis and genealogical analysis of chlorotypes, one consisting of chlorotypes from the western region and the second consisting of those from the eastern region. Significant genetic differences between the two regions might be attributed to vicariance and restricted gene flow, and this vicariance could be explained by the physical environmental heterogeneity on each side of the Tanaka-Kaiyong Line. Following the uplift of the Tibetan Plateau, the reorganization of the major river drainages was primarily caused by river separation and capture events. These historical events could change the distribution of S. davidii from fragmented to continuous (Upper/Lower Jinshajiang and Yalongjiang/Daduhe), and from continuous to fragmented (Nujiang and Jinshajiang/Honghe). However, spatial and temporal patterns of phylogeographic divergence are strongly associated with historical disjunction rather than modern drainage connections. Moreover, the following north-south split in the eastern region and effective isolation with their genetic diversity were essentially modelled by genetic drift. The higher chlorotype richness and genetic divergence for populations in western region compared with other two regions suggests that there were multipe refugia or in situ survival of S. davidii in the Himalayan-Hengduan Mountain region. Fixation of chlorotypes in the northeastern region and near fixation in the southeastern region suggest a recent colonization of these areas. We further found that this species underwent past range expansion around 37-303 thousand years ago (kya). The southeastern populations likely experienced a demographic expansion via unidirectional gene flow along rivers, while northeastern populations underwent a more northward expansion, both from initial populations (s) (21, 22, 23) preserved on eastern refugia (Jinshajiang). This process might have been accompanied with a series of founder effects or bottlenecks making populations genetically impoverished. 3. Phylogeographic analysisbased on nuclear sequence，We sequenced the nuclear (ncpGS) region in all populations sampled, recovering 23 nuclear haplotypes. Compared to cpDNA, both NST (0.470) and GST (0.338) were relatively lower, but NST was also significantly larger than GST. 37.10% of the total variation was distributed among regions which was much lower than that shown by chlorotypes. Thus, more extensive distribution of nuclear haplotypes was exhibited across the geographical range instead of the strong population subdivision observed in chlorotypes. Similarly to the chloroplast data, we found that genetic differentiation of nDNA was positively correlated with the geographical distance, but the increase in the geographical distance between populations did not increase the genetic differentiation of nDNA as rapidly as that of cpDNA. These contrasting levels between the chloroplast and nuclear genomes of S. davidii are likely due to limited gene flow of cpDNA by seeds vs. the extensive gene flow of nDNA by wind-mediated pollen in the population history. We also determined from nuclear markers that haplotype diversity was reduced in the southeastern and northeastern regions due to the loss of rare haplotypes in western region. This reduction of gene diversity is also a signature of founder events or recent bottleneck during post-glacial colonization. However, nuclear diversity within populations remains high. This provides evidence that regionally pollen flow might be sufficiently high to blur the genetic identity of founder populations over a reasonably large spatial scale.3. Relationships among three varieties，The phylogenetic analysis identified two phylogroups of chlorotypes, corresponding to S. davidii var. davidii and var. chuansinesis. The former was distinguished by the abscence of predonminant nuclear haplotype H1 of the latter. The monophyletic group of chlorotypes in var. davidii and var. liangshanesis showed their relatively close relationship. And their genetic divergence from the third variety appears to be relative to their slight morphological difference in leaf size and the divergent environmental niche spaces they occupy. Thus, the observed differences in morphological characters between var. chuansinesis and other two varieties can be explained by the seed dispersal limitation illustrated above (as inferred by geographical separation) and by environmental heterogeneity (as inferred by precipitation or elevation) or by a combination of both. After all, the geological changes, drainage reorganization, and floristic differences following the Himalayan uplift have been suggested to affect the genetic structure of S. davidii. These results provide new insights into the phylogeographic pattern of plants in China. In addition, the unique population genetic structure found in S. davidii has provided important insights into the evolutionary history of this species. The genetic profile uncovered in this study is also critical for its conservation management. Our study has uncovered the existence of at least two ‘evolutionary significant units’ independent units within S. davidii, corresponding to var. davidii from eastern region and var. chuansinensis from western region. The conservation efforts should first focus on most western populations and on the southeastern ones exhibiting high levels of genetic diversity, while the genetically homogeneous northeastern populations located in the degraded Loess Plateau should require much greater conservation 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Taxus wallichiana complex represents an old relict conifer lineage that survived through the Tertiary. It is currently distributed in the mountain forests in South and Southwest China south of the Qinling Mountains. In the present study, we explored phylogeography of the complex by using two chloroplast DNA regions, one nuclear ribosomal DNA spacer region and eight microsatellite (SSR) loci. The main conclusions can be summarized as follows:1. Phylogeographic pattern based on chloroplast haplotypes，There were 11 cpDNA haplotypes identified in the T. wallichiana complex The complex showed a high level of genetic diversity and obvious genetic differentiation. The 44 sampled populations showed obvious genetic structure, which could be divided into five groups, namely the Huanan group, the Daba group, the Emei group, the Yunnan group and the Qinling group. There was extremely high genetic differentiation among groups, but not significant within group. The divergence times of the five lineages, estimated using average mutation rates of trnL-trnF, fell in the Pliocene. 2. Phylogeographic patterns based on ITS sequences，These included 38 unique ‘haplotypes’ based on ITS data. Their analysis showed that the T. wallichiana complex possessed a high genetic diversity. These populations could be divided into four groups, namely the Huanan group, the Daba/Emei group, the Yunnan group and the Qinling group. Based on all results, it appears that the major lineages constituting the T. wallichiana complex have arisen before Quaternary glaciation cycles, and may have survived isolated in different refugia. During interglacial periods some lineages appear to have come in contact and hybridizedbut other lineages merged forming populations with mixed haplotypes without signs of hybridization. The present-day phylogeographical distribution pattern of the T. wallichiana complex might thus be the result of repeated expansion / contractions of populations during interglacial / glacial cycles.3. Population genetic analysis using microsatellite (SSR) markers，Eight SSR loci were used for population genetic analysis on the T. wallichiana complex. A lower level of genetic diversity at the population level and high genetic differentiation among population was detected. The results of structure analysis were similar to those on the ITS data, dividing the populations into four groups (lineages). According to the results here, it was deduced that each of the 4 lineages of the T. wallichiana complex may possessed respective glacial refugia, and some lineages (such as the Qinling and Huanan lineage) might have survived in multiple refugia in the Quaternay glaciations. The present distribution pattern of this complex was likely influenced by the uplift of the QTP and Quaternary glaciation.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.date.issued.year&advanced=false&fq=dc.language.iso_filter%3A%E4%B8%AD%E6%96%87&query1=%25E9%25A9%25AC%25E5%2585%2588%25E8%2592%25BF&&fq=dc.project.title_filter%3AThe%5C+Taxus%5C+wallichiana%5C+complex%5C+represents%5C+an%5C+old%5C+relict%5C+conifer%5C+lineage%5C+that%5C+survived%5C+through%5C+the%5C+Tertiary.%5C+It%5C+is%5C+currently%5C+distributed%5C+in%5C+the%5C+mountain%5C+forests%5C+in%5C+South%5C+and%5C+Southwest%5C+China%5C+south%5C+of%5C+the%5C+Qinling%5C+Mountains.%C2%A0In%5C+the%5C+present%5C+study%2C%5C+we%5C+explored%5C+phylogeography%5C+of%5C+the%5C+complex%5C+by%5C+using%5C+two%5C+chloroplast%5C+DNA%5C+regions%2C%5C+one%5C+nuclear%5C+ribosomal%5C+DNA%5C+spacer%5C+region%5C+and%5C+eight%5C+microsatellite%5C+%5C%28SSR%5C%29%5C+loci.%5C+The%5C+main%5C+conclusions%5C+can%5C+be%5C+summarized%5C+as%5C+follows%5C%3A1.%5C+Phylogeographic%5C+pattern%5C+based%5C+on%5C+chloroplast%5C+haplotypes%EF%BC%8CThere%5C+were%5C+11%5C+cpDNA%5C+haplotypes%5C+identified%5C+in%5C+the%5C+T.%5C+wallichiana%5C+complex%5C+The%5C+complex%5C+showed%5C+a%5C+high%5C+level%5C+of%5C+genetic%5C+diversity%5C+and%5C+obvious%5C+genetic%5C+differentiation.%5C+The%5C+44%5C+sampled%5C+populations%5C+showed%5C+obvious%5C+genetic%5C+structure%2C%5C+which%5C+could%5C+be%5C+divided%5C+into%5C+five%5C+groups%2C%5C+namely%5C+the%5C+Huanan%5C+group%2C%5C+the%5C+Daba%5C+group%2C%5C+the%5C+Emei%5C+group%2C%5C+the%5C+Yunnan%5C+group%5C+and%5C+the%5C+Qinling%5C+group.%5C+There%5C+was%5C+extremely%5C+high%5C+genetic%5C+differentiation%5C+among%5C+groups%2C%5C+but%5C+not%5C+significant%5C+within%5C+group.%5C+The%5C+divergence%5C+times%5C+of%5C+the%5C+five%5C+lineages%2C%5C+estimated%5C+using%5C+average%5C+mutation%5C+rates%5C+of%5C+trnL%5C-trnF%2C%5C+fell%5C+in%5C+the%5C+Pliocene.%C2%A02.%5C+Phylogeographic%5C+patterns%5C+based%5C+on%5C+ITS%5C+sequences%EF%BC%8CThese%5C+included%5C+38%5C+unique%5C+%E2%80%98haplotypes%E2%80%99%5C+based%5C+on%5C+ITS%5C+data.%5C+Their%5C+analysis%5C+showed%5C+that%5C+the%5C+T.%5C+wallichiana%5C+complex%5C+possessed%5C+a%5C+high%5C+genetic%5C+diversity.%C2%A0These%5C+populations%5C+could%5C+be%5C+divided%5C+into%5C+four%5C+groups%2C%5C+namely%5C+the%5C+Huanan%5C+group%2C%5C+the%5C+Daba%5C%2FEmei%5C+group%2C%5C+the%5C+Yunnan%5C+group%5C+and%5C+the%5C+Qinling%5C+group.%5C+Based%5C+on%5C+all%5C+results%2C%5C+it%5C+appears%5C+that%5C+the%5C+major%5C+lineages%5C+constituting%5C+the%5C+T.%5C+wallichiana%5C+complex%5C+have%5C+arisen%5C+before%5C+Quaternary%5C+glaciation%5C+cycles%2C%5C+and%5C+may%5C+have%5C+survived%5C+isolated%5C+in%5C+different%5C+refugia.%5C+During%5C+interglacial%5C+periods%5C+some%5C+lineages%5C+appear%5C+to%5C+have%5C+come%5C+in%5C+contact%5C+and%5C+hybridizedbut%5C+other%5C+lineages%5C+merged%5C+forming%5C+populations%5C+with%5C+mixed%5C+haplotypes%5C+without%5C+signs%5C+of%5C+hybridization.%5C+The%5C+present%5C-day%5C+phylogeographical%5C+distribution%5C+pattern%5C+of%5C+the%5C+T.%5C+wallichiana%5C+complex%5C+might%5C+thus%5C+be%5C+the%5C+result%5C+of%5C+repeated%5C+expansion%5C+%5C%2F%5C+contractions%5C+of%5C+populations%5C+during%5C+interglacial%5C+%5C%2F%5C+glacial%5C+cycles.3.%5C+Population%5C+genetic%5C+analysis%5C+using%5C+microsatellite%5C+%5C%28SSR%5C%29%5C+markers%EF%BC%8CEight%5C+SSR%5C+loci%5C+were%5C+used%5C+for%5C+population%5C+genetic%5C+analysis%5C+on%5C+the%5C+T.%5C+wallichiana%5C+complex.%5C+A%5C+lower%5C+level%5C+of%5C+genetic%5C+diversity%5C+at%5C+the%5C+population%5C+level%5C+and%5C+high%5C+genetic%5C+differentiation%5C+among%5C+population%5C+was%5C+detected.%5C+The%5C+results%5C+of%5C+structure%5C+analysis%5C+were%5C+similar%5C+to%5C+those%5C+on%5C+the%5C+ITS%5C+data%2C%5C+dividing%5C+the%5C+populations%5C+into%5C+four%5C+groups%5C+%5C%28lineages%5C%29.%C2%A0According%5C+to%5C+the%5C+results%5C+here%2C%5C+it%5C+was%5C+deduced%5C+that%5C+each%5C+of%5C+the%5C+4%5C+lineages%5C+of%5C+the%5C+T.%5C+wallichiana%5C+complex%5C+may%5C+possessed%5C+respective%5C+glacial%5C+refugia%2C%5C+and%5C+some%5C+lineages%5C+%5C%28such%5C+as%5C+the%5C+Qinling%5C+and%5C+Huanan%5C+lineage%5C%29%5C+might%5C+have%5C+survived%5C+in%5C+multiple%5C+refugia%5C+in%5C+the%5C+Quaternay%5C+glaciations.%5C+The%5C+present%5C+distribution%5C+pattern%5C+of%5C+this%5C+complex%5C+was%5C+likely%5C+influenced%5C+by%5C+the%5C+uplift%5C+of%5C+the%5C+QTP%5C+and%5C+Quaternary%5C+glaciation."},{"jsname":"The floritistic composition, characteristics, endemism, origin and evolution were studied on the base of literature checked, field investigation, specimens checked and previous research work. The main result are as follows: 1. Guishan Region is rich in seed-plants. The Guishan Region flora consists of 129 families and 488 genera and 1069 species of which 6 species in 5 genera and 3 families belong to Gymnosperm, 842 species in 381 genera and 100 families belong to dicotyledon, 421 species in 102 genera and 26 families belong to monocotyledon.2. Flora Composition: The floristic elements of 62.02% tropical families and 37.98% temperate one indicates that the flora of this region has a close relationship with tropical flora historically and geographically. The floristic elements of 44.68% tropical genera and 52.96% temperate one reveals dominant temperate property, which one of the typical floristic characters in subtropical mountain region; the floristic elements of 53.83% tropical species(excluding species which are endemic to china and distribute world-wide ), 46.17% temperate ones indicates that the flora is subtropical in nature. 433 species are endemic to China ,43.96% of all the species (excluding the species world-wide).Very few species (44 species endemic to China accounted for 10.16%) distribute to the North, most of which distribute only to Shanxi, Henan, Gansu Province., indicating weak feature of temperate flora of Guishan region in nature. Statistical analysis showed that indicates that the flora of this region has a close relationship with tropical flora historically and geographically, shows transitional features in flora between tropical to temperate flora.. 3. By the comparison with five adjacent limestone and non-limestone flora on the level of family and genus, we found that the flora of Guishan Region is most closely related to the flora of Shishan Mountain and Xiaobaicaoling and Wuliang Mountain all of which situate in Central Yunnan. So the flora position of Guishan Region is: Central Yunnan Plaetau Subregion, the Yunnan Plaetau Region, the Sino-Himalayan forest Subkingdom, the east Asiatic Kingdom.4. The endemic plants in Guishan Region are rich, and the flora of Guishan Region shows limestone features. 10 genera are endemic to China, 433 species are endemic to China. Among the Chineses endemic plants, 1 genes and 7 species are endemic to Guishan Region in which 1 genes(Parasiometrum) and 3 species (Begonia guishanensis, Petrocosmea guishanensis, Parasiometrum mileens) are limestone exclusive.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.date.issued.year&advanced=false&fq=dc.language.iso_filter%3A%E4%B8%AD%E6%96%87&query1=%25E9%25A9%25AC%25E5%2585%2588%25E8%2592%25BF&&fq=dc.project.title_filter%3AThe%5C+floritistic%5C+composition%2C%5C+characteristics%2C%5C+endemism%2C%5C+origin%5C+and%5C+evolution%5C+were%5C+studied%5C+on%5C+the%5C+base%5C+of%5C+literature%5C+checked%2C%5C+field%5C+investigation%2C%5C+specimens%5C+checked%5C+and%5C+previous%5C+research%5C+work.%5C+The%5C+main%5C+result%5C+are%5C+as%5C+follows%5C%3A%5C+1.%5C+Guishan%5C+Region%5C+is%5C+rich%5C+in%5C+seed%5C-plants.%5C+The%5C+Guishan%5C+Region%5C+flora%5C+consists%5C+of%5C+129%5C+families%5C+and%5C+488%5C+genera%5C+and%5C+1069%5C+species%5C+of%5C+which%5C+6%5C+species%5C+in%5C+5%5C+genera%5C+and%5C+3%5C+families%5C+belong%5C+to%5C+Gymnosperm%2C%5C+842%5C+species%5C+in%5C+381%5C+genera%5C+and%5C+100%5C+families%5C+belong%5C+to%5C+dicotyledon%2C%5C+421%5C+species%5C+in%5C+102%5C+genera%5C+and%5C+26%5C+families%5C+belong%5C+to%5C+monocotyledon.2.%5C+Flora%5C+Composition%5C%3A%5C+The%5C+floristic%5C+elements%5C+of%5C+62.02%25%5C+tropical%5C+families%5C+and%5C+37.98%25%5C+temperate%5C+one%5C+indicates%5C+that%5C+the%5C+flora%5C+of%5C+this%5C+region%5C+has%5C+a%5C+close%5C+relationship%5C+with%5C+tropical%5C+flora%5C+historically%5C+and%5C+geographically.%5C+The%5C+floristic%5C+elements%5C+of%5C+44.68%25%5C+tropical%5C+genera%5C+and%5C+52.96%25%5C+temperate%5C+one%5C+reveals%5C+dominant%5C+temperate%5C+property%2C%5C+which%5C+one%5C+of%5C+the%5C+typical%5C+floristic%5C+characters%5C+in%5C+subtropical%5C+mountain%5C+region%5C%3B%5C+the%5C+floristic%5C+elements%5C+of%5C+53.83%25%5C+tropical%5C+species%5C%28excluding%5C+species%5C+which%5C+are%5C+endemic%5C+to%5C+china%5C+and%5C+distribute%5C+world%5C-wide%5C+%5C%29%2C%5C+46.17%25%5C+temperate%5C+ones%5C+indicates%5C+that%5C+the%5C+flora%5C+is%5C+subtropical%5C+in%5C+nature.%5C+433%5C+species%5C+are%5C+endemic%5C+to%5C+China%5C+%2C43.96%25%5C+of%5C+all%5C+the%5C+species%5C+%5C%28excluding%5C+the%5C+%5C+species%5C+world%5C-wide%5C%29.Very%5C+few%5C+species%5C+%5C%2844%5C+species%5C+endemic%5C+to%5C+China%5C+accounted%5C+for%5C+10.16%25%5C%29%5C+distribute%5C+to%5C+the%5C+North%2C%5C+most%5C+of%5C+which%5C+distribute%5C+only%5C+to%5C+Shanxi%2C%5C+Henan%2C%5C+Gansu%5C+Province.%2C%5C+indicating%5C+weak%5C+feature%5C+of%5C+temperate%5C+flora%5C+of%5C+Guishan%5C+region%5C+in%5C+nature.%5C+Statistical%5C+analysis%5C+showed%5C+that%5C+%5C+indicates%5C+that%5C+the%5C+flora%5C+of%5C+this%5C+region%5C+has%5C+a%5C+close%5C+relationship%5C+with%5C+tropical%5C+flora%5C+historically%5C+and%5C+geographically%2C%5C+shows%5C+transitional%5C+features%5C+in%5C+flora%5C+between%5C+tropical%5C+to%5C+temperate%5C+flora..%5C+3.%5C+By%5C+the%5C+comparison%5C+with%5C+five%5C+adjacent%5C+limestone%5C+and%5C+non%5C-limestone%5C+flora%5C+on%5C+the%5C+level%5C+of%5C+family%5C+and%5C+genus%2C%5C+we%5C+found%5C+that%5C+the%5C+flora%5C+of%5C+Guishan%5C+Region%5C+is%5C+most%5C+closely%5C+related%5C+to%5C+the%5C+flora%5C+of%5C+Shishan%5C+Mountain%5C+and%5C+Xiaobaicaoling%5C+and%5C+Wuliang%5C+Mountain%5C+all%5C+of%5C+which%5C+situate%5C+in%5C+Central%5C+Yunnan.%5C+So%5C+the%5C+flora%5C+position%5C+of%5C+Guishan%5C+Region%5C+is%5C%3A%5C+Central%5C+Yunnan%5C+Plaetau%5C+Subregion%2C%5C+the%5C+Yunnan%5C+Plaetau%5C+Region%2C%5C+the%5C+Sino%5C-Himalayan%5C+forest%5C+Subkingdom%2C%5C+the%5C+east%5C+Asiatic%5C+Kingdom.4.%5C+The%5C+endemic%5C+plants%5C+in%5C+Guishan%5C+Region%5C+are%5C+rich%2C%5C+and%5C+the%5C+flora%5C+of%5C+Guishan%5C+Region%5C+shows%5C+limestone%5C+features.%5C+10%5C+genera%5C+are%5C+endemic%5C+to%5C+China%2C%5C+433%5C+species%5C+are%5C+endemic%5C+to%5C+China.%5C+Among%5C+the%5C+Chineses%5C+endemic%5C+plants%2C%5C+1%5C+genes%5C+and%5C+7%5C+species%5C+are%5C+endemic%5C+to%5C+Guishan%5C+Region%5C+in%5C+which%5C+1%5C+genes%5C%28Parasiometrum%5C%29%5C+and%5C+3%5C+species%5C+%5C%28Begonia%5C+guishanensis%2C%5C+Petrocosmea%5C+guishanensis%2C%5C+Parasiometrum%5C+mileens%5C%29%5C+are%5C+limestone%5C+exclusive."},{"jsname":"The origin center and diversity center of the genus Ligularia were considered to be central China and Hengduan Mountains Region (HMR) of China, respectively. In this research, we studied the phylogeographic pattern of L. hodgsonii and L. tongolensis, which was distributed in the origin center and diversity center, respectively. We aimed to infer the evolutionary process of Ligularia species. 1. The phylogeography of L. hodgsonii，Here, we investigated the phylogeographic history of L. hodgsonii disjunctively distributed in China and Japan. Two hundred and eighty individuals were collected from 29 natural populations, 23 located in China and 6 in Japan. A total of 19 haplotypes were identified with the combination of three chloroplast DNA (cpDNA) sequences variations (trnQ-5’rps16, trnL-rpl32 and psbA-trnH). At the species level, a high level of haplotype diversity (Hd) and total genetic diversity (HT) was detected. However, the average intrapopulation diversity (HS) was very low. Consequently, the population differentiation(NST = 0.989, GST = 0.933 ) was pronounced with a significant phylogeographic structure (NST > GST, p < 0.01). At the regional level, Chinese and Japanese L. hodgsonii had a similar estimate of genetic diversity (China: Hd = 0.847, HT = 0.869; Japan: Hd = 0.766, HT = 0.867). Populations from China and Japan possess unique sets of haplotypes, and no haplotypes were shared between the regions. Furthermore, both the phyloegenetic and network analyses recovered the haplotypes of China and Japan as two distinct clades. Thus, we suggested the disjunct distribution of L. hodgsonii in China and Japan may present the climatic vicariant relicts of the ancient widely distributed populations. After divergence, this species within each region experienced independent evolutionary process. In China, L. hodgsonii was distributed around the Sichuan Basin. This distribution range can be divided into five regions. They were Jiajin Mountain region, E’mei Mountain region, Yunnan-Guizhou Plateau region, Wushan-Wuling Mountain region and Qinling Mountain region. Twelve haplotypes were indentified within these regions. Each region had its own specific haplotypes, which had different ancestry in the network. We deduced that Chinese L. hodgsonii might survive the LGM in multiple isolated refugia around the Sichuan Basin. In Japan, L. hodgsonii was disjunctively distributed in northern Honshu and Hokkaido. Seven haplotypes were identified within this region. However, the genetic diversity in Honshu (Hd = 0.821) was much higher than that in Hokkaido (Hd = 0.513). And all haplotypes in Hokkaido were derived from Honshu. This haplotype distribution suggested that the northern Honshu could have served as refuge in Japan. Nested clade analysis (NCA) indicated multiple forces including the vicariance and long-distance dispersal affected the disjunctive distribution among populations of L. hodgsonii in Japan.2. The phylogeography of L. tongolensis，Ligularia tongolensis was distributed along the Jinshajiang watershed, Yalongjiang watershed and Wumeng Mountain. In order to deduce the demographic history of this species, we sequenced two chloroplast DNA (cpDNA) intergenic spacers (trnQ-5’rps16, trnL-rpl32) in 140 individuals from 14 populations of three groups (Jinshajiang vs. Yalongjiang vs. Wumeng) within this species range. High levels of haplotype diversity (Hd = 0.814) and total genetic diversity (HT = 0.862) were detected at the species level, based on a total oftwelve haplotypes identified. However, the intrapopulation diversity (HS = 0.349) was low, which led to the high levels of genetic divergence (GST = 0.595, NST = 0.614, FST = 0.597). In consideration of the speciation of L. tongolensis resulting from the uplifts of the Qinghai-Tibetan Plateau (QTP), we thought the present genetic structure of L. tongolensis was shaped by the fragmentation of ancestral populations during the courses of QTP uplifts. This was further supported by the absence of IBD tests (r = –0.291, p = 0.964), which suggest that the differentiation had not occurred in accordance with the isolation by distance model. The genetic differentiation in L. tongolensis appears to be associated with historical events. Meanwhile, H2 and H5, the dominant haplotypes that located on internal nodes and deviated from extinct ancestral haplotype in the network, were detected to be shared between Jinshajiang and Yalongjiang groups. We deduced that ancestral populations of this species might have had a continuous distribution range, which was then fragmented and isolated by the following tectonic events. Finally, the ancestral polymorphism, H2 and H5, were randomly allocated in Jinshajiang watershed and Yalongjiang watershed. Meanwhile, H5 was the dominant haplotype in Jinshajiang watershed; H7 was the domiant haplotype in Yalongjiang watershed and Wumeng Mountain. This haplotype distribution pattern indicated that each group might have served as a refuge for L. tongolensis during the Quaternary Glaciation. Postglacial demographic expansion was supported by unimodal mismatch distribution and star-like phylogenies, with expansion ages of 274 ka B. P. for this 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a town of Shangri-la County, Diqing Prefecture, was chosen as the main field site for studying the structure and characters of traditional agricultural ecosystem, by using approaches of ethnobotany, cultural anthropology and ecology. Combined with interviewing exercises in Hanpi village, Jiantang Township, this paper also discussed the impact of traditional management on the biocultural diversity. The results showed: Traditional agroecosystem in Shangri-la is an integrated system with three subsystems, which are farming, forest and grazing subsystem. The seasonal shifting grazing activity in Shangri-la, following the natural season change and the recover process of plants, is a sustainable management that protects the local biodiversity. However, along with the decay of shifting grazing tradition recently, the local Tibetans turned to use grass land and forest which is close to villages as the main grazing lands. It increased the pasturing pressure to these areas and caused productivity decreasing and biodiversity. As a symbolic part of Tibetan culture in Shangri-la, the sacred mountain culture has played a significant role in biodiversity conservation by restricting human’s behavior. The Tibetan traditional culture, indigenous knowledge and traditional ecosystem management in Shangri-la has contributed to the biodiversity conservation in this area. However, this research indicated that under the pressure of mainstream culture and market economy, traditional knowledge is vanishing; old crop land races are decreasing; diverse land use management is inclining to be single and seasonal shifting grazing tradition is fading away. The change of diversity to singularity might cause some negative impacts on the local environment and ecosystem. In this paper, advices were also given on how to combine Tibetan traditional knowledge and management experiences into sustainable development of modern agriculture. In this thesis, genetic diversity of Musella lasiocarpa (Franch.) C. Y. Wu ex H. W. Li, a plant endemic to southwest China, was also discussed through the approach of SSR markers. The wild populations of M. lasiocarpa are very rare now due to the habitat fragment and long time human’s disturbance. By conducting broad field investigation, we have found 5 wild populations near the boarder of Yunnan and Sichuan province. Seventeen microsatellite markers were isolated from M. lasiocarpa by using FIASCO method. 8 primers were selected to do the further genetic population structure and genetic diversity analysis. The results showed that genetic diversity of M. lasiocarpa’s wild populations is higher than cultivated populations. The genetic diversity difference between wild and cultivated populations is related to the different reproduction systems. Adopting the way of asexuality reproduction, the genetic basis of cultivated populations become narrow that decrease the genetic diversity. AMOVA analysis showed that 37.19% genetic differentiation is among populations and 62.81% is within population. Genetic differentiation among different populations is related to the limited gene communication. POPGENE analysis indicated that there is very little gene flow among different populations (0.4916), which is the main reason of high genetic differentiation among M. lasiocarpa 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