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1.
Curr Biol ; 34(6): 1271-1283.e4, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38460512

RESUMEN

Madagascar is a biogeographically unique island with a remarkably high level of endemism. However, endemic taxa in Madagascar are massively threatened due to unprecedented pressures from anthropogenic habitat modification and climate change. A comprehensive phylogeny-based biodiversity evaluation of the island remains lacking. Here, we identify hotspots of taxonomic and phylogenetic plant diversity and neo- and paleo-endemism by generating a novel dated tree of life for the island. The tree is based on unprecedented sampling of 3,950 species (33% of the total known species) and 1,621 genera (93% of the total known genera and 69% of endemic genera) of Malagasy vascular plants. We find that island-endemic genera are concentrated in multiple lineages combining high taxonomic and phylogenetic diversity. Integrating phylogenetic and geographic distribution data, our results reveal that taxon richness and endemism are concentrated in the northern, eastern, and southeastern humid forests. Paleo-endemism centers are concentrated in humid eastern and central regions, whereas neo-endemism centers are concentrated in the dry and spiny forests in western and southern Madagascar. Our statistical analysis of endemic genera in each vegetation region supports a higher proportion of ancient endemic genera in the east but a higher proportion of recent endemic genera in the south and west. Overlaying centers of phylogenetic endemism with protected areas, we identify conservation gaps concentrated in western and southern Madagascar. These gaps should be incorporated into conservation strategies to aid the protection of multiple facets of biodiversity and their benefits to the Malagasy people.


Asunto(s)
Biodiversidad , Ecosistema , Plantas , Madagascar , Filogenia
2.
BMC Biol ; 21(1): 239, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37904140

RESUMEN

BACKGROUND: The Sino-Himalayan flora harbors highly diverse high-elevation biotas, but our understanding of its evolutionary history in temporal and spatial dimensions is limited. In this study, we integrated a dated phylogenetic tree with comprehensive species distribution data to investigate changes over time and space in floristic elements, including the tropical, Tethys, northern temperate, and East Asian floristic elements, across the entire Sino-Himalaya and its three floristic regions: the Yunnan Plateau, Hengduan Mountains, and East Himalaya regions. RESULTS: Our results revealed that the Sino-Himalayan flora developed from lowland biomes and was predominantly characterized by tropical floristic elements before the collision between the Indian subcontinent and Eurasia during the Early Cenozoic. Subsequently, from the Late Eocene onwards, the uplifts of the Himalaya and Hengduan Mountains transformed the Sino-Himalayan region into a wet and cold plateau, on which harsh and diverse ecological conditions forced the rapid evolution of local angiosperms, giving birth to characteristic taxa adapted to the high altitudes and cold habitat. The percentage of temperate floristic elements increased and exceeded that of tropical floristic elements by the Late Miocene. CONCLUSIONS: The Sino-Himalayan flora underwent four significant formation periods and experienced a considerable increase in endemic genera and species in the Miocene, which remain crucial to the present-day patterns of plant diversity. Our findings support the view that the Sino-Himalayan flora is relatively young but has ancient origins. The three major shifts in the divergence of genera and species during the four formation periods were primarily influenced by the uplifts of the Himalaya and Hengduan Mountains and the onset and intensification of the Asian monsoon system. Additionally, the temporal patterns of floristic elements differed among the three floristic regions of the Sino-Himalaya, indicating that the uplift of the Himalaya and surrounding areas was asynchronous. Compared to the Yunnan Plateau region, the East Himalaya and Hengduan Mountains experienced more recent and drastic uplifts, resulting in highly intricate topography with diverse habitats that promoted the rapid radiation of endemic genera and species in these regions.


Asunto(s)
Biodiversidad , Ecosistema , Embarazo , Humanos , Femenino , Filogenia , China , Plantas
3.
Plant Divers ; 44(3): 255-261, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35769595

RESUMEN

Medicinal plants are the primary material basis for disease prevention and treatment in traditional Chinese medicine (TCM). The conservation and sustainable utilization of these medicinal plants is critical for the development of the TCM industry. However, wild medicinal plant resources have sharply declined in recent decades. To ameliorate the shortage of medicinal plant resources, it is essential to explore the development potential of the TCM industry in different geographical regions. For this purpose, we examined the spatial distribution of commonly used medicinal plants in China, the number of Chinese medicinal material markets, and the number of TCM decoction piece enterprises. Specifically, multispecies superimposition analysis and Thiessen polygons were used to reveal the optimal range for planting bulk medicinal plants and the ideal regions for building Chinese medicinal material markets, respectively. Furthermore, we quantitatively analyzed mismatches between the spatial distribution of commonly used medicinal plant richness, Chinese medicinal material markets, and TCM decoction piece enterprises. We found that the areas suitable for growing commonly used medicinal plants in China were mainly distributed in Hengduan Mountain, Nanling Mountain, Wuling Mountain, and Daba Mountain areas. The Thiessen polygon network based on Chinese medicinal material market localities showed there are currently fewer markets in southwestern, northwestern, and northeastern China than in central and southern China. TCM decoction piece enterprises are concentrated in a few provinces, such as Hebei and Jiangxi. We found that the distribution of commonly used medicinal plants, Chinese medicinal material markets and TCM decoction piece enterprises are mismatched in Henan, Shaanxi, Hunan, Hubei, Zhejiang, Fujian, Chongqing, and Xizang. We recommend strengthening development of the TCM industry in Henan, Hunan, Zhejiang, Shaanxi, Hubei, Chongqing, Fujian, and Xizang; building more Chinese medicinal material markets in southwestern, northwestern, and northeastern China; and establishing medicinal plant nurseries in resource-rich provinces to better protect and domesticate local medicinal plants.

4.
J Integr Plant Biol ; 64(1): 105-117, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34773376

RESUMEN

The flora of China is well known for its high diversity and endemism. Identifying centers of endemism and designating conservation priorities are essential goals for biodiversity studies. However, there is no comprehensive study from a rigorous phylogenetic perspective to understand patterns of diversity and endemism and to guide biodiversity conservation in China. We conducted a spatial phylogenetic analysis of the Chinese angiosperm flora at the generic level to identify centers of neo- and paleo-endemism. Our results indicate that: (i) the majority of grid cells in China with significantly high phylogenetic endemism (PE) were located in the mountainous regions; (ii) four of the nine centers of endemism recognized, located in northern and western China, were recognized for the first time; (iii) arid and semiarid regions in Northwest China were commonly linked to significant PE, consistent with other spatial phylogenetic studies worldwide; and (iv) six high-priority conservation gaps were detected by overlaying the boundaries of China's nature reserves on all significant PE cells. Overall, we conclude that the mountains of southern and northern China contain both paleo-endemics (ancient relictual lineages) and neo-endemics (recently diverged lineages). The areas we highlight as conservation priorities are important for broad-scale planning, especially in the context of evolutionary history preservation.


Asunto(s)
Magnoliopsida , Biodiversidad , Evolución Biológica , China , Magnoliopsida/genética , Filogenia
5.
PhytoKeys ; 166: 97-103, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33239957

RESUMEN

Pternopetalum paucifoliolatum, a new species from Sixigou Scenic Area, Emeishan City, Sichuan Province, is proposed and described. Diagnostic morphological characters, full description, detailed illustrations, and a distribution map are provided. The new species is similar to P. porphyronotum in possessing the 1-pinnate leaves and the abaxially purple-red leaflets, but differs from the latter by shorter stature, fewer leaflets ((1-) 3-7) and rays (5-8), the leaflet margin white-ciliate. The new species, which is assessed as Critically Endangered (CR), was only found on limestone cliffs. We also provide a new key to the species of Pternopetalum.

6.
Plant Divers ; 42(2): 67-73, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32373764

RESUMEN

For a quantitative biogeographical regionalization, the choice of an appropriate dissimilarity index to measure pairwise distances is crucial. Several different metrics have been used, but there is no specific study to test the impact of metric choice on biogeographical regionalization. We herein applied a hierarchical cluster analysis on the mean nearest taxon distance (MNTD) and the phylogenetic turnover component of the Sørensen dissimilarity index (pßsim) pairwise distances to generate two schemes of phylogenetic regionalization of the Chinese flora, and then evaluated the effect of metric choice. Floristic regionalization based on MNTD was influenced by richness differences, but regionalization based on pßsim can clearly reflect the evolutionary history of the Chinese flora. We provided a brief description of the five regions identified by pßsim, and the regionalization can help develop strategies to effectively conserve the taxa and floristic regions with different origins and evolutionary histories.

7.
Mol Phylogenet Evol ; 129: 15-26, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30026123

RESUMEN

Species represent the most basic unit of taxonomy. As such, species delimitation represents a crucial issue for biodiversity conservation. Taxonomic practices were revolutionized in the last three decades due to the increasing availability of molecular phylogenetic data. The genus Triplostegia (Caprifoliaceae) traditionally consists of two species, T. glandulifera and T. grandiflora, distinguishable mainly based on quantitative morphological features. In this study, we sequenced nine chloroplast loci (i.e., accD, psbK-psbI, rbcL-accD, rpoB-trnC, rps16-trnQ, trnE-trnT, trnF-ndhJ, trnH-psbA, trnS-trnG) and one nuclear locus (ITS) of 16 individuals of Triplostegia representing the entire distribution range of both species recognized. Furthermore, we also obtained whole chloroplast sequences for 11 of the 16 individuals for which silica gel-dried leaves were available. Our phylogenetic analyses integrating chloroplast genome sequences and multiple loci data revealed that Triplostegia includes four main clades that largely match geography. Neither T. grandiflora nor T. glandulifera was recovered as monophyletic and no diagnosable differences in leaf, flower, and pollen traits were detected between the two species, indicating the need for a revised species circumscription within Triplostegia. Our study highlights the importance of combining data from different sources while defining species limits.


Asunto(s)
Caprifoliaceae/genética , Sitios Genéticos , Genoma del Cloroplasto , Secuencia de Bases , Cloroplastos/genética , Genes de Plantas , Geografía , Filogenia , Hojas de la Planta/anatomía & histología , Polen/ultraestructura , Especificidad de la Especie
8.
Nature ; 554(7691): 234-238, 2018 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-29420476

RESUMEN

High species diversity may result from recent rapid speciation in a 'cradle' and/or the gradual accumulation and preservation of species over time in a 'museum'. China harbours nearly 10% of angiosperm species worldwide and has long been considered as both a museum, owing to the presence of many species with hypothesized ancient origins, and a cradle, as many lineages have originated as recent topographic changes and climatic shifts-such as the formation of the Qinghai-Tibetan Plateau and the development of the monsoon-provided new habitats that promoted remarkable radiation. However, no detailed phylogenetic study has addressed when and how the major components of the Chinese angiosperm flora assembled to form the present-day vegetation. Here we investigate the spatio-temporal divergence patterns of the Chinese flora using a dated phylogeny of 92% of the angiosperm genera for the region, a nearly complete species-level tree comprising 26,978 species and detailed spatial distribution data. We found that 66% of the angiosperm genera in China did not originate until early in the Miocene epoch (23 million years ago (Mya)). The flora of eastern China bears a signature of older divergence (mean divergence times of 22.04-25.39 Mya), phylogenetic overdispersion (spatial co-occurrence of distant relatives) and higher phylogenetic diversity. In western China, the flora shows more recent divergence (mean divergence times of 15.29-18.86 Mya), pronounced phylogenetic clustering (co-occurrence of close relatives) and lower phylogenetic diversity. Analyses of species-level phylogenetic diversity using simulated branch lengths yielded results similar to genus-level patterns. Our analyses indicate that eastern China represents a floristic museum, and western China an evolutionary cradle, for herbaceous genera; eastern China has served as both a museum and a cradle for woody genera. These results identify areas of high species richness and phylogenetic diversity, and provide a foundation on which to build conservation efforts in China.


Asunto(s)
Biodiversidad , Magnoliopsida/clasificación , Filogenia , China , Conservación de los Recursos Naturales/métodos , Evolución Molecular , Mapeo Geográfico , Análisis de Regresión , Análisis Espacio-Temporal
9.
Ecol Evol ; 8(2): 1131-1146, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29375785

RESUMEN

Current disjunct patterns can result from long-distance dispersal or postglacial contraction. We herein investigate the evolutionary history of Triplostegia to elucidate the disjunction between the Himalaya-Hengduan Mountain region (HHM) and Taiwan (TW). Genetic structure of Triplostegia was investigated for 48 populations using sequences from five chloroplast loci and the ribosomal nuclear internal transcribed spacer. Divergence time estimation, ancestral area reconstruction, and species distribution modeling (SDM) were employed to examine the biogeographic history of Triplostegia. Substantial genetic differentiation among populations from southwestern China (SW), Central China (CC), and TW was detected. Triplostegia was inferred to have originated in SW, and diversification began during the late Miocene; CC was colonized in the mid-Pliocene, and TW was finally colonized in the early Pleistocene. SDM suggested an expansion of climatically suitable areas during the Last Glacial Maximum and range contraction during the Last interglacial in Triplostegia. Disjunction between HHM and TW in Triplostegia is most likely the consequence of topographic isolation and postglacial contraction. The potential climatic suitability areas for Triplostegia by 2070s (2061-2080) are predicted to slightly shrink and move northward. With continued global warming and human-induced deforestation, extinction risk may increase for the cold-adapted species, and appropriate strategies should be employed for ecosystem conservation.

10.
Food Chem ; 219: 490-495, 2017 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-27765256

RESUMEN

Vaccinium glaucoalbum, a perennial evergreen shrub, is naturally distributed in high-altitude areas. In this study, the composition and content of polyphenolic compounds in the fruit and leaf of V. glaucoalbum were characterized. In total, 24 chemical compounds were detected and identified by HPLC-DAD and HPLC-ESI-MS2. Among all the compounds determined, 15 were anthocyanins and detected in fruit, 5 were flavonols and monitored in leaf, and 4 were chlorogenic acids and found in both fruit and leaf. The total anthocyanin content (TAC) of fruit (682mg/100gFW) was the highest among wild Vaccinium berries in China which have been investigated for now, and the total flavonol content of leaf was 2764mg/100gFW. The antioxidant activity of both fruit and leaf was assessed by DPPH and FRAP assays. Given its high TAC and strong antioxidant activity, the fruit of V. glaucoalbum has great potential in functional food.


Asunto(s)
Antioxidantes/metabolismo , Frutas/metabolismo , Extractos Vegetales/metabolismo , Hojas de la Planta/metabolismo , Polifenoles/metabolismo , Vaccinium/metabolismo , Antocianinas/metabolismo , China , Cromatografía Líquida de Alta Presión , Flavonoles/metabolismo , Espectrometría de Masas
12.
Beijing Da Xue Xue Bao Yi Xue Ban ; 44(4): 639-42, 2012 Aug 18.
Artículo en Chino | MEDLINE | ID: mdl-22898863

RESUMEN

OBJECTIVE: To present the preliminary experience of the operative procedure and clinical outcomes of retroperitoneal laparoscopic nephroureterectomy (RPLNU) with a midline lower abdominal transperitoneal incision for native upper urinary tract transitional cell carcinoma (UUT-TCC) ipsilateral to a transplanted kidney. METHODS: In the study, 15 renal recipients with native UUT-TCC ipsilateral to a transplanted kidney were operated on with RPLNU via a midline lower abdominal transperitoneal incision between November 2005 and January 2009. Retroperitoneal laparoscopic nephrectomy was performed first and followed by cystoscopic excision of ipsilateral ureteral orifice with bladder cuff. A 6-8 cm midline lower abdominal incision was made. The distal ureter was dissected transperitoneally into the intramural segment and extracted completely. The intact specimen was removed manually via the same incision. The cystostomy was generally sutured. RESULTS: The mean operation time was 253 minutes. The mean estimated blood loss was 245 mL. Three patients needed blood transfusion. No open conversion was required during the retroperitoneoscopic nephrectomy. Two of the patients suffered from minor complications. The pathological findings confirmed UUT-TCC in all the patients with 9 of the pelvises and 9 of the ureters. Five of the patients were involved with bladder TCC. With the mean follow-up of 35 months, none of them had retroperitoneal recurrence or distant metastasis, 2 of the 5 patients with bladder TCC had recurrence in bladder and 4 had contralateral native UUT-TCC after the first unilateral nephroureterectomy. CONCLUSION: RPLNU with a midline lower abdominal transperitoneal incision may be a safe and feasible alternative for native UUT-TCC ipsilateral to a transplanted kidney with satisfactory oncologic outcomes.


Asunto(s)
Carcinoma de Células Transicionales/cirugía , Trasplante de Riñón , Laparoscopía/métodos , Nefrectomía/métodos , Neoplasias Ureterales/cirugía , Abdomen/cirugía , Femenino , Humanos , Masculino , Espacio Retroperitoneal , Estudios Retrospectivos , Uréter/cirugía
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