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Sicyoideibasidia yunnanensis,a new species of Agaricales(Basidiomycota)from southwest China
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作者 DENG Yinglian CHEN Meng +4 位作者 LIU Wanting WANG Kaisheng LIU Linfeng LI Wen ZHAO Changlin 《菌物学报》 北大核心 2025年第11期16-29,共14页
In present study,morphological observation and phylogenetic relationship analyses by using multiple loci DNA sequences,including the internal transcribed spacer(ITS)regions,the large subunit nuclear ribosomal RNA gene... In present study,morphological observation and phylogenetic relationship analyses by using multiple loci DNA sequences,including the internal transcribed spacer(ITS)regions,the large subunit nuclear ribosomal RNA gene(nLSU),and the translation elongation factor 1-αgene(tef1),result in discovery of Sicyoideibasidia yunnanensis sp.nov.of Agaricales.The species is characterized by resupinate basidiomata with smooth,cream to yellowish hymenial surface,a monomitic hyphal system,generative hyphae bearing simple septa,and ellipsoid basidiospores.Phylogenetic analysis based on ITS+nLSU+tef1 data shows that the new species is closely related with S.bambusicola and S.punctata. 展开更多
关键词 TAXONOMY molecular systematics multigene phylogeny yunnan Province new species
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A New Antiarch,Bothriolepis zhujiangyuanensis sp.nov.,from the Eifelian(Middle Devonian)of Qujing,Yunnan,SW China
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作者 XIAN Zumin PAN Zhaohui +4 位作者 WANG Jianhua JIA Liantao ZHAO Yingtian LUO Yanchao ZHU Min 《Acta Geologica Sinica(English Edition)》 2025年第1期1-14,共14页
A new species of Bothriolepis(Placodermi,Antiarcha),B.zhujiangyuanensis sp.nov.,is described from the Eifelian(Middle Devonian)Shangshuanghe Formation at the Pearl River Source Scenic Area,Qujing,Yunnan Province,south... A new species of Bothriolepis(Placodermi,Antiarcha),B.zhujiangyuanensis sp.nov.,is described from the Eifelian(Middle Devonian)Shangshuanghe Formation at the Pearl River Source Scenic Area,Qujing,Yunnan Province,southwestern China and is characterized by a broad postpineal plate bearing a straight anterior margin,a premedian plate wider than long,and a weakly developed dorsal median ridge of the trunk shield.As the eighth Bothriolepis taxon in China,B.zhujiangyuanensis sp.nov.provides a wealth of morphological data to clarify the intrageneric interrelationships.Maximum parsimony analysis,using a revised data set of the genus with 76 ingroup taxa and 72 characters,yields a well-resolved consensus tree for Bothriolepis.The phylogenetic result shows a sister-group relationship between B.zhujiangyuanensis and B.babichevi from Kazakhstan,corroborating the biogeographic proximity between the South China and Kazakhstania blocks during the Middle Devonian. 展开更多
关键词 vertebrate paleontology placoderms Bothriolepis phylogeny PALEOBIOGEOGRAPHY EIFELIAN yunnan Province
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Neolithic to Bronze Age human maternal genetic history in Yunnan,China
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作者 Xinyu Wei Ming Zhang +30 位作者 Rui Min Zhilong Jiang Jiayang Xue Zhonghua Zhu Haibing Yuan Xiaorui Li Dongyue Zhao Peng Cao Feng Liu Qingyan Dai Xiaotian Feng Ruowei Yang Xiaohong Wu Changcheng Hu Minmin Ma Xu Liu Yang Wan Fan Yang Ranchao Zhou Lihong Kang Guanghui Dong Wanjing Ping Tianyi Wang Bo Miao Fan Bai Yuxin Zheng Yuxiao Liu Melinda A.Yang Wenjun Wang E.Andrew Bennett Qiaomei Fu 《Journal of Genetics and Genomics》 2025年第4期483-493,共11页
Yunnan in southwest China is a geographically and ethnically complex region at the intersection of southern China and Southeast Asia,and a focal point for human migrations.To clarify its maternal genetic history,we ge... Yunnan in southwest China is a geographically and ethnically complex region at the intersection of southern China and Southeast Asia,and a focal point for human migrations.To clarify its maternal genetic history,we generated 152 complete mitogenomes from 17 Yunnan archaeological sites.Our results reveal distinct genetic histories segregated by geographical regions.Maternal lineages of ancient populations from northwestern and northern Yunnan exhibit closer affinities with past and present-day populations from northern East Asia and Xizang,providing important genetic evidence for the migration and interaction of populations along the Tibetan-Yi corridor since the Neolithic.Between 5500 and 1800 years ago,central Yunnan populations maintained their internal genetic relationships,including a 7000-year-old basal lineage of the rare and widely dispersed haplogroup M61.At the Xingyi site,changes in mitochondrial DNA haplogroups occurred between the Late Neolithic and Bronze Age,with haplogroups shifting from those predominant in the Yellow River region to those predominant in coastal southern China.These results highlight the high diversity of Yunnan populations during the Neolithic to Bronze Age. 展开更多
关键词 Ancient DNA yunnan Genetic history Mitochondrial genomes NEOLITHIC Bronze age
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Meta-transcriptomic analysis of tick virome diversity and ecological characteristics in Yunnan Province,southwestern China
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作者 Rong Xiang Fengjuan Tian +13 位作者 Jing Li Jihu Yang Danni Zeng Yilin Zhao Zhi Luo Miao Li Chaobo Du Wenqiang Shi Chunfeng Luo Xiaohe Liu Yi Sun Yigang Tong Chunhong Du Jiafu Jiang 《Virologica Sinica》 2025年第6期898-909,共12页
Emerging tick-borne viruses are posing an increasing health concern.However,there is limited knowledge about the distribution characteristics of tick virome in Yunnan Province,southwestern China,where it is distinguis... Emerging tick-borne viruses are posing an increasing health concern.However,there is limited knowledge about the distribution characteristics of tick virome in Yunnan Province,southwestern China,where it is distinguished by its diverse eco-climatic zones and rich biodiversity,making it a hotspot for studying tick-borne pathogens.The present study aimed to explore the diversity and ecological characteristics of tick virome in Yunnan Province,especially to identify novel potentially pathogenic viruses threatening human and vertebrate animals,and to investigate host-specific viral tropisms and their transmission characteristics.Using a meta-transcriptomic approach,the study analyzed the viromes of 448 individual ticks and approximately 10,000 eggs collected from nine counties with different hosts,altitudes and landscapes.The ticks encompassed eight species across four genera.The study focused on delineating virome diversity profiles,evaluating host-specific viral tropisms,and investigating potential transovarial transmission through viral contigs identification and Sanger sequencing.The study identified 53 viral families,revealing significant virome diversity and geographic and environmental specificity.Haemaphysalis and Ixodes ticks exhibited greater viral richness and abundance,with host taxonomy being a primary influencing factor.We determined 102 viral genomes encompassing 35 species,comprising 15 novel viruses identified when their RNAdependent RNA polymerase/DNA polymerase sequences exhibited<90% amino acid identity to known viruses.The novel vectors for vertebrate-related or potentially pathogenic viruses were also detected,thus providing new insights into transmission cycles.The evidence for transovarial transmission was reinforced by the absence of significant differences in Chuviridae and Nairoviridae families between female ticks and their eggs.These findings underscore the necessity of continuous surveillance to avert the spillover of emerging pathogens. 展开更多
关键词 TICK Tick-borne virus Virome Ecological characteristics yunnan Province
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Detrital Zircon Geochronology of Early Jurassic Successions in the Central Yunnan Basin,Southwest China:Implications of Sedimentary Provenance and Tectonic Evolution
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作者 Liangdong Luo Jun Wang +4 位作者 Yujie Yuan Zerui Liu Mengyan Jiao Yingao Zhang Saike Zhang 《Journal of Earth Science》 2025年第4期1465-1478,共14页
The Central Yunnan Basin(CYB)that tectonically located on the southwest margin of the Yangtze Block and to the eastern segment of the Paleo-Tethys tectonic domain,is a typical‘red bed'sedimentary basin formed sin... The Central Yunnan Basin(CYB)that tectonically located on the southwest margin of the Yangtze Block and to the eastern segment of the Paleo-Tethys tectonic domain,is a typical‘red bed'sedimentary basin formed since Late Triassic.The CYB is composed of mega-thick fluvial and lacustrine facies successions.However,the tectonic evolution and sedimentary provenance studies on this basin are scarce.In this study,we report new detrital zircon ages of four sandstones from the Lower Jurassic Fengjiahe Formation(FJF),including four major clusters of 2060-1810,870-760,485-430,and 280-254 Ma,with sporadic Archean,Cambrian,and Triassic ages.We interpret that the Archaean and Proterozoic zircons were mainly derived from the western Yangtze Block,which may recycle from the Jiangnan Orogen,the Cathaysia Block and the Proterozoic igneous rocks.Ordovician and Silurian zircons were probably from the Ailaoshan orogenic belt,and the Lancang Group in western Yunnan,as well as the Yangtze,Cathaysia and Indosinian blocks.Permian zircons probably came from the Ailaoshan orogenic belt and the Emeishan basalt.The youngest zircon age of~212.9 Ma indicates that the depositional age of the FJF is younger than the Norian stage.We also proposed a geodynamic model of the CYB and the Ailaoshan orogenic belt during the Mesozoic.The Simao Block to the west of the CYB constituted the Ailaoshan orogenic belt and collaged with the Yangtze Block during the Early Triassic,provided sedimentary provenance to the CYB.The Changning-Menglian zone that composed of the Baoshan and the Simao Blocks,uplifted in the Late Triassic and provided provenance to the CYB.Collapse of the Ailaoshan orogenic belt in Late Triassic probably provided channel for source materials that transported from the Lincang granites to the CYB.We propose a transtensional tectonic setting of the central Yunnan during the Early Jurassic,after a short collision during the Indosinian Movement in the Late Triassic. 展开更多
关键词 central yunnan Basin detrital zircon Fengjiahe Formation JURASSIC sedimentary provenance Yimen area SEDIMENTATION
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Petrogenesis,Tectonics,and Metallogenic Potential of Early Paleozoic S-type Granites in Pinghe,Southwestern Yunnan,China
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作者 LI Guangjie CHEN Yongqing 《Acta Geologica Sinica(English Edition)》 2025年第5期1314-1327,共14页
A systematic study of early Paleozoic S-type granites in Pinghe enhances our understanding of the tectonic evolution of proto-Tethys and provides a foundation for exploring rare metal deposits in the region.The Pinghe... A systematic study of early Paleozoic S-type granites in Pinghe enhances our understanding of the tectonic evolution of proto-Tethys and provides a foundation for exploring rare metal deposits in the region.The Pinghe granites consist of monzogranite and leucogranite.Zircon U-Pb dating shows that the emplacement ages of the monzogranite and leucogranite are 502.0 Ma and 500.9 Ma,respectively.All samples have high SiO_(2) content and a weakly to strongly peraluminous character(A/CNK=1.08-1.23),consistent with S-type granites.The monzogranite has relatively high CaO,Sr,Ba,and CaO/Na_(2)O ratios but lower Rb.In contrast,the leucogranite has lower CaO,Sr,Ba,and CaO/Na_(2)O ratios but higher Rb.The similar ε_(Nd)(t)values(−9.3 to−8.4)and Pb isotopic compositions((^(206)Pb/^(204)Pb)t=18.03-19.36,(^(207)Pb/^(204)Pb)t=15.66-15.76,(^(208)Pb/^(204)Pb)t=37.97-38.55)suggest that the monzogranite formed through partial melting of crustal greywacke,while the leucogranite originated from partial melting of crustal pelite.Regional geological studies suggest that these S-type granites in Pinghe were emplaced in an active continental margin setting,associated with the westward subduction of the proto-Tethys oceanic slab.The geochemical characteristics of leucogranite are consistent with those of tungsten-tin-related granites,indicating significant metallogenic potential for W and Sn deposits. 展开更多
关键词 early Paleozoic granites S-type granites tectonics and metallogenic potential proto-Tethys Southwestern yunnan
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Estelle’s Idyllic Lodge in Yunnan
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作者 MENG JIAXIN 《China Today》 2025年第6期72-73,共2页
A French architect finds her ideal life in a scenic town in southwest China.IN the scenic Benzilan Town in China’s Yunnan Province,64-year-old French architect Estelle Achard enjoys an idyllic life in a rustic Tibeta... A French architect finds her ideal life in a scenic town in southwest China.IN the scenic Benzilan Town in China’s Yunnan Province,64-year-old French architect Estelle Achard enjoys an idyllic life in a rustic Tibetan house named Tulu Lodge,where she offers homestay services to visitors from across the globe. 展开更多
关键词 rustic tibetan house french architect tulu lodgewhere tulu lodge benzilan town homestay services idyllic life yunnan province
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The Bayesian Gaussian mixture model with nearest-neighbor distance(BGMM-NND)algorithm:A new earthquake clustering method and its application to the Sichuan–Yunnan Block
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作者 JieYi Hou Feng Hu +1 位作者 Yang Zang LingYuan Meng 《Earth and Planetary Physics》 2025年第4期828-841,共14页
We propose a robust earthquake clustering method:the Bayesian Gaussian mixture model with nearest-neighbor distance(BGMM-NND)algorithm.Unlike the conventional nearest neighbor distance method,the BGMM-NND algorithm el... We propose a robust earthquake clustering method:the Bayesian Gaussian mixture model with nearest-neighbor distance(BGMM-NND)algorithm.Unlike the conventional nearest neighbor distance method,the BGMM-NND algorithm eliminates the need for hyperparameter tuning or reliance on fixed thresholds,offering enhanced flexibility for clustering across varied seismic scales.By integrating cumulative probability and BGMM with principal component analysis(PCA),the BGMM-NND algorithm effectively distinguishes between background and triggered earthquakes while maintaining the magnitude component and resolving the issue of excessively large spatial cluster domains.We apply the BGMM-NND algorithm to the Sichuan–Yunnan seismic catalog from 1971 to 2024,revealing notable variations in earthquake frequency,triggering characteristics,and recurrence patterns across different fault zones.Distinct clustering and triggering behaviors are identified along different segments of the Longmenshan Fault.Multiple seismic modes,namely,the short-distance mode,the medium-distance mode,the repeating-like mode,the uniform background mode,and the Wenchuan mode,are uncovered.The algorithm's flexibility and robust performance in earthquake clustering makes it a valuable tool for exploring seismicity characteristics,offering new insights into earthquake clustering and the spatiotemporal patterns of seismic activity. 展开更多
关键词 earthquake clustering BGMM-NND algorithm Sichuan–yunnan Block seismic modes
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Geochemistry and U-Pb geochronology of the granite porphyry in Bainiuchang,Southeastern Yunnan,China
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作者 Nan Shi Jun Zhu +9 位作者 Xuelong Liu Shitao Zhang Guangzhi Meng Hong Zhang Jialong Cheng Jiehu Zhou Bode Lu Junshan Dao Xue Mi Maohuang Fan 《Acta Geochimica》 2025年第2期325-347,共23页
The Bainiuchang Ag-polymetallic ore deposit,located in southeastern Yunnan,China,is one of the region's largest deposits.However,the hyp abyssal granite porphyry within this mining area has yet to be comprehensive... The Bainiuchang Ag-polymetallic ore deposit,located in southeastern Yunnan,China,is one of the region's largest deposits.However,the hyp abyssal granite porphyry within this mining area has yet to be comprehensively investigated.In this study,we conducted geochemical,geochronological,whole-rock Sr-Nd isotope,and zircon Hf isotope analyses on granite porphyry samples collected from the Bainiuchang deposit.The results indicate that the granite porphyry formed between 87.5 and 87.4 Ma in the Late Yanshanian period.Geochemically,the granite is strongly peraluminous,with high silica and alkali contents consistent with S-type granite characteristics.The granite porphyry is enriched in large-ion lithophile elements(Rb,Th,U,and K)and is relatively depleted in Ba and Sr.The initial ^(87)Sr/^(86)Sr ratios are high(0.71392-0.71585),accompanied by low ε_(Nd)(t)values(-8.9 to-8.2).The zircons exhibited similarly low ε_(Hf)(t)values(-9.31 to-3.6).These data suggest that the porphyry-forming magma originated from a continental crustal source.The two-stage Hf and Nd model ages are estimated at 1534-1216 Ma and 1615-1561 Ma,respectively.Thus,the granite porphyry likely formed under a strike-slip extensional setting in the Late Yanshanian period and resulted from the re-melting of Proterozoic basement metagreywackes.This porphyry shares a similar magmatic origin with concealed granite bodies within the deposit and is associated with structural reactivation during the Yanshanian.The findings of this study provide valuable insights into the tectonomagmatic mineralization processes in the B ainiuchang area. 展开更多
关键词 Zircon U-Pb ages GEOCHEMISTRY Sr-Nd isotopes Granite porphyry Bainiuchang silver polymetallic ore deposit Southeastern yunnan
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A Study on the Beliefs and Attitudes of Nurses in Yunnan Province Towards Nurse Prescriptive Authority
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作者 Yulin Lu Jian Chen +3 位作者 Ying Li Jun Yu Yanyu Chen Jiangyu Xue 《Journal of Clinical and Nursing Research》 2025年第1期194-202,共9页
Objective: To investigate the current beliefs and attitudes of nurses in Yunnan Province toward prescriptive authority, analyze the influencing factors, and provide evidence for future research and policy formulation ... Objective: To investigate the current beliefs and attitudes of nurses in Yunnan Province toward prescriptive authority, analyze the influencing factors, and provide evidence for future research and policy formulation to support the establishment of nurses’ prescriptive authority in China. Method: A cross-sectional survey was conducted among 937 nurses in Yunnan Province using the Beliefs and Attitudes Scale on Nurses’ Prescriptive Authority. The scale assessed four dimensions: perceived need, self-efficacy, perceived benefits, and perceived barriers. Multiple linear regression analysis was used to identify factors influencing the overall score and each dimension. Results: The total score of the Beliefs and Attitudes Scale was 89.17 ± 17.69, indicating a moderate level of awareness and positive attitude among nurses. The highest-scoring dimension was perceived benefits (34.94 ± 8.04), while the lowest was perceived barriers (15.23 ± 3.5). Age was identified as a significant factor influencing the overall score and self-efficacy dimension (P < 0.05). Years of practice influenced the perceived benefits dimension (P = 0.051), while gender, age, and professional title were key factors affecting the perceived barriers dimension (P < 0.05). Male nurses and senior nurses demonstrated more caution toward potential risks associated with prescriptive authority. Conclusion: Nurses in Yunnan Province exhibit moderate levels of belief in and attitudes toward prescriptive authority, with age being the most significant influencing factor. Tailored training programs, policy promotion, and practical guidance are recommended to enhance nurses’ understanding and support for prescriptive authority, thereby improving nursing practices and addressing regional healthcare challenges. 展开更多
关键词 Nurses’prescriptive authority Beliefs and attitudes Influencing factors yunnan Province Nursing policy
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Multiple-stage W mineralization in the Guanfang W deposit,southeastern Yunnan Province,China:Insights from scheelite in-situ trace elemental and Sr isotopic analyses
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作者 Bin Sun Yi Liu +4 位作者 Zhigang Kong Xuelong Liu Xiaojun Jiang Chao Li Wenchang Li 《Acta Geochimica》 2025年第1期112-127,共16页
The Guanfang large-scale W deposit is located in the W polymetallic ore concentration area of Bozhushan in southeastern Yunnan,China.Despite extensive research,the fluid evolution process of the deposit remains ambigu... The Guanfang large-scale W deposit is located in the W polymetallic ore concentration area of Bozhushan in southeastern Yunnan,China.Despite extensive research,the fluid evolution process of the deposit remains ambiguous,leading to controversy regarding its genesis.This study conducted a detailed field geological survey,with systematic sampling of the KT6 orebody,to delineate mineralization stages.Fine mineralogy work,including the use of CL images of scheelite,in-situ LA-ICP-MS trace elements,and Sr isotopes,was carried out on diff erent generations of scheelite formed in various stages.The findings identified the evolution of fluids in the mineralization process,shedding light on the genesis of the deposit.The study revealed four mineralization stages at the Guanfang W deposit:prograde skarn stage,retrograde skarn stage,quartz-sulfide stage,and carbonate-fluorite stage.Diff erent generations of scheelite(Sch I,Sch II,Sch III)were observed in the first three stages,displaying distinct chondrite-normalized REE patterns.The REE of Sch I mainly substituted into the Ca site by REE^(3+)+□_(Ca),and there may be a similar substitution of Nb for REE,whereas it is not the main substitution method.The REE of Sch II mainly enter the scheelite lattice in the form of REE 3++Na+,and there may be a substitution of Nb for REE isomorphism.In the early stage,The REE of Sch III was mainly replaced by Nb for REE isomorphism,while in the later stage,the replacement mode of REE^(3+)+□_(Ca)coexisted with it.The Mo content in scheelite,along with the corresponding Eu anomalies in both scheelite and garnet,collectively imply that the ore-forming fluids during various mineralization stages were predominantly oxidizing,with only slight reducibility observed in Sch II.The in-situ Sr isotope ratios of scheelite concentrates ranged from 0.7093 to 0.7153,resembling those of the Bozhushan granite,indicating a relationship between W mineralization and granite.In addition,the Y/Ho ratios of scheelite from various mineralization stages exhibit a narrow range(19-31),with a pronounced correlation between the contents of Y and Ho and a similar trend in their variation.This consistency suggests that the Guanfang deposit has undergone a uniform or comparable evolutionary process,implying a stable ore-forming fluid across diff erent mineralization stages. 展开更多
关键词 Guanfang W deposit Trace elements of scheelite In-situ Sr isotopes Southeast yunnan
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A comprehensive study on in situ stress field characteristics and changes in rock mechanical properties in deep mines in northeastern Yunnan,China
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作者 Hui Wang Bangtao Sun +4 位作者 Cong Cao Shibo Yu He Wang Ye Yuan Hua Zhong 《Deep Underground Science and Engineering》 2025年第2期241-254,共14页
The Maoping lead–zinc mining area is a significant metal mine site in northeastern Yunnan.In this study,both hydraulic fracturing in situ stress testing and ultrasonic imaging logging were first carried out in the mi... The Maoping lead–zinc mining area is a significant metal mine site in northeastern Yunnan.In this study,both hydraulic fracturing in situ stress testing and ultrasonic imaging logging were first carried out in the mining area.Second,930 focal mechanism solutions and 231 sets of stress data near the mining area were collected.Then,the variations in the type of in situ stress field,the magnitude of in situ stress,the direction of horizontal principal stress,and the ratio of lateral pressure were analyzed to characterize the distribution of the in situ stress field.On this basis,a new method using borehole breakouts and drilling-induced fractures was proposed to determine the stress direction.Finally,the evolution of the mechanical properties of dolomite with burial depth was analyzed and the influence of rock mechanical properties on the distributions of the in situ stress field was explored.The results show that the in situ stress in the mining area isσ_(H)>σ_(V)>σ_(h),indicating a strike–slip stress state.The in situ stress is high in magnitude,and its value increases with burial depth.The maximum and minimum horizontal lateral stress coefficients are stabilized at approximately 1.22 and 0.73,respectively.The direction of the maximum horizontal principal stress is NW,mainly ranging from N58.44°W to N59.70°W.The stress field inferred from the focal mechanism solution is in good agreement with the test results.The proportion of structural planes with dip angles between 30°and 75°exceeds 80%,and the dip direction of the structural planes is mainly NW to NWW.The line density of structural planes shows high density in shallow areas and low density in deep areas.More energy tends to be accumulated in rocks with higher elastic modulus and strength,leading to higher in situ stress levels.These findings are of significant reference for mine tunnel layout,support design optimization,and disaster prevention. 展开更多
关键词 current stress field in situ stress measurement northeastern yunnan rock mechanical properties structural plane characteristics
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Identifying Social-ecological Driving Mechanisms of Farmland Transfer at the County Scale in Central Yunnan Urban Agglomeration, China
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作者 WANG Yiting LI Chun +4 位作者 ZHAO Fangkai CHEN Shanshan LI Ninglv YI Shengyuan CHEN Liding 《Chinese Geographical Science》 2025年第3期454-471,共18页
Farmland transfer is an important land policy for reducing agricultural fragmentation and improving land use efficiency.Many studies have investigated the driving forces of farmland transfer at the farmers’scale.Howe... Farmland transfer is an important land policy for reducing agricultural fragmentation and improving land use efficiency.Many studies have investigated the driving forces of farmland transfer at the farmers’scale.However,the overall spatial distribution and driving mechanisms of farmland transfer at the county scale has been less quantified.In this study,we evaluated farmland transfer and its spatial pattern in Central Yunnan Urban Agglomeration(CYUA)of China by using statistical data at the county scale in 2020.A so-cial-ecological indicator system,comprising natural endowment,social indicators,economic indicators,and landscape patterns,was es-tablished to explore the relationship between farmland transfer and its driving factors.Additionally,a heuristic structural equation mod-el(SEM)was employed to disentangle direct and indirect drivers of farmland transfer.The results indicated that significant spatial clusters of farmland transfer,with high transfer rates concentrated in highly urbanized areas and low transfer rates prevalent in tradition-al ethnic minority regions.Farmland transfer is primarily driven by soil quality,landscape patterns,terrain,and social-economic rurality.Specifically,higher soil quality and improved landscape connectivity facilitate farmland transfer directly,while gentler slopes promote farmland transfer indirectly by supporting better educational opportunities and fewer minority population.Improving rural vocational training and optimizing landscape patterns through land consolidation and redistribution are important in the mountainous areas.This study can provide valuable analytical framework for farmland management for other mountainous regions. 展开更多
关键词 farmland transfer mountainous urban agglomeration social-ecological indicators structural equation modeling landscape pattern Central yunnan Urban Agglomeration China
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Assessment of Genetic Diversity of Yunnan,Tibetan,and Xinjiang Wheat Using SSR Markers 被引量:26
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作者 王海燕 王秀娥 +1 位作者 陈佩度 刘大钧 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第7期623-633,共11页
A total of 206 SSR (Simple Sequence Repeats) primer pairs were used to detect genetic diversity in 52 accessions of three unique wheat varieties of western China. A total of 488, 472, and 308 allelic variants were d... A total of 206 SSR (Simple Sequence Repeats) primer pairs were used to detect genetic diversity in 52 accessions of three unique wheat varieties of western China. A total of 488, 472, and 308 allelic variants were detected in 31 Yunnan, 15 Tibetan and 6 Xinjiang wheat accessions with an average of PIC values 0.2764, 0.3082, and 0.1944, respectively. Substantial differences in allelic polymorphisms were detected by SSR markers in all the 21 chromosomes, the 7 homoeologous groups, and the three genomes (A, B, and D) in Yunnan, Tibetan, and Xinjiang wheat. The highest and lowest allelic polymorphisms in all the 21 chromosomes were observed in 3B and 1D chromosomes, respectively. The lowest and highest allelic polymorphisms among the seven homoeologous groups was observed in 6 and 3 homoeologous groups, respectively. Among the three genomes, B genome showed the highest, A the intermediate, and D the lowest allelic polymorphism. The genetic distance (GD) indexes within Yunnan, Tibetan, and Xinjiang wheat, and between different wheat types were calculated. The GD value was found to be much higher within Yunnan and Tibetan wheat than within Xinjiang wheat, but the GD value between Yunnan and Tibetan wheat was lower than those between Yunnan and Xinjiang wheat, and between Tibetan and Xinjiang wheat. The cluster analysis indicated a closer relationship between Yunnan and Tibetan wheat than that between Yunnan and Xinjiang wheat or between Tibetan and Xinjiang wheat. 展开更多
关键词 yunnan wheat Tibetan wheat Xinjiang wheat genetic diversity SSR markers
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Genetic differentiations between randomly and selectively bred pig populations in Yunnan,China 被引量:10
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作者 亐开兴 吴桂生 +4 位作者 苟潇 严达伟 连林生 Mumtaz Baig 张亚平 《Zoological Research》 CAS CSCD 北大核心 2011年第3期255-261,共7页
To assess the genetic diversity between randomly and selectively bred populations,we sequenced 438 bp of the mitochondrial DNA control region from 102 pigs.These samples represented four native pig breeds,one nucleus ... To assess the genetic diversity between randomly and selectively bred populations,we sequenced 438 bp of the mitochondrial DNA control region from 102 pigs.These samples represented four native pig breeds,one nucleus and one conservation herd from Yunnan,China.Twenty haplotypes with sixteen polymorphic sites were identified.The number of haplotypes in the nucleus herd of Saba pig and the conservation herd of Banna miniature pig were restricted to three and one,respectively,while the randomly bred pig populations exhibited over six haplotypes.Notably,haplotype diversity in randomly bred populations was significantly greater than the selectively bred populations(h=0.732 vs.0.425 and 0,exact test,P≤0.0036).These findings demonstrate that selective breeding generated low genetic diversity compared to randomly bred pig breeds.A timely intervention and well programmed breeding approach would stop further genetic diversity reduction in the nucleus and conservation herds of native pig breeds.Otherwise,selective breeding would dramatically reduce genetic diversity in only several years,indicating that sharp contradictions exist between breeding,conservation and genetic diversity.Genetic relationships are discussed based on net genetic distances among pig populations. 展开更多
关键词 yunnan pig breeds Genetic diversity Randomly bred population Selectively bred population
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A New Species of the Genus Garra from Nujiang River Basin, Yunnan, China (Teleostei: Cyprinidae) 被引量:6
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作者 陈自明 赵晟 杨君兴 《Zoological Research》 CAS CSCD 北大核心 2009年第4期438-444,共7页
A new species of the subfamily Labeoninae, Garra nujiangensis Chen and Yang, sp. nov. is recognized from a secondary branch of Nujiang River (upper Salween) in Zhenkang county, Yunnan province, China. It can be dist... A new species of the subfamily Labeoninae, Garra nujiangensis Chen and Yang, sp. nov. is recognized from a secondary branch of Nujiang River (upper Salween) in Zhenkang county, Yunnan province, China. It can be distinguished from other beardless Garra species by the following combination of characters: 12 - 14 circumpedunele scales; 48 - 50 lateral- line scales; a pair of rudimentary rostral barbels present in little individuals; 8 - 9 branched dorsal-fin rays; 5 - 6 scales between dorsal-fin origin and lateral line and 3 - 4 scales between pelvic-fin origin and lateral line; caudal peduncle relatively stouter; length between snout tip to posterior margin of eye longer than body depth at anal fin origin; head length longer than body depth at dorsal fin origin; prepelvic length 50.0% - 53.7% of standard length; pre-anus length 58.9% - 63.9% of standard length; body width 16.7% - 19.6% of standard length; body depth at dorsal fin 19.2% - 22.6% of standard length. The present study also verified that the presence of tiny barbells is a juvenile character in some beardless Garra species, such as G. nujiangensis and G. alticorpora. 展开更多
关键词 Garra CYPRINID New species yunnan
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Suitability Assessment of Mononychellus tanajoa(Acari:Tetranychidae) in Yunnan Based on Maxent Model 被引量:4
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作者 卢辉 陈青 +1 位作者 卢芙萍 徐雪莲 《Agricultural Science & Technology》 CAS 2011年第12期1905-1908,共4页
[Objective] This study aimed to analyze the potential geography distribution of M.tanajoa in Yunnan.[Method] The suitability of M.tanajoa in Yunnan was studied in this paper using Maxent and ArcGIS,based on the biolog... [Objective] This study aimed to analyze the potential geography distribution of M.tanajoa in Yunnan.[Method] The suitability of M.tanajoa in Yunnan was studied in this paper using Maxent and ArcGIS,based on the biological data and known distribution of M.tanajoa,and meteorological data from years of 1950-2000 in WorldClim.[Result] The results showed that there were four levels of suitability assessment of M.tanajoa in Yunnan,in which western and eastern areas are in the most suitability,including part areas of Simao,Lincang,Baoshan,Nujiang,Diqing,Qujing and Wenshan areas.[Conclusion] The potential geographic distribution of M.tanajoa in Yunnan defined in this paper constructed the theory basis and technical support for scientifically forming of quarantine policy and measure for M.tanajoa in China. 展开更多
关键词 Mononychellus tanajoa yunnan Suitability assessment MAXENT
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Relationship between Rice Cultural Diversity and Ecological Environment in Yunnan Province of China 被引量:3
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作者 曾亚文 杜娟 +3 位作者 普晓英 罗曦 杨树明 杨涛 《Agricultural Science & Technology》 CAS 2012年第10期2247-2256,共10页
[Objective] This paper aims to confirm that Yunnan is one origin center of rice and human in the world.[Method] The complicated and unique ecological environment in Yunnan makes Yunnan Province the largest center of g... [Objective] This paper aims to confirm that Yunnan is one origin center of rice and human in the world.[Method] The complicated and unique ecological environment in Yunnan makes Yunnan Province the largest center of genetic diversity and cultural diversity of rice and human being as well as the cradle of human childhood.[Result] The genetic diversity and cultural diversity of rice and human being is closely related to the ecosystem diversity.Rice civilization in Yunnan can be divided into four types,including the diversity center region of rice civilization in southwestern Yunnan,diffusion region of rice civilization of Hani-Zhuang in southern Yunnan,rice civilization region of water-drought rotation in central Yunnan and poverty region of rice civilization in northern Yunnan.Southwestern Yunnan is not only the center of genetic ecological diversity and rice cultural diversity,but also the center of origin and diversity of crop genetic diversity.It is not only a transitional region among East Asia continent,South Asian sub-continent and Indo-China Peninsula,but also a core integration area of Chinese culture,Indian culture and Mid-south Peninsula culture which all merge with the local culture.[Conclusion] Yunnan is one common sphere where the origin of human evolution is closely related to the origin of rice evolution. 展开更多
关键词 Rice culture Ecological environment Origin evolution Human being yunnan
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Documentation Concordance,Sharing and Utilization of Tea Germplasm Resources in Yunnan 被引量:3
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作者 刘本英 宋维希 +6 位作者 孙雪梅 蒋会兵 马玲 矣兵 季鹏章 汪云刚 王平盛 《Agricultural Science & Technology》 CAS 2011年第12期1842-1848,共7页
In this paper,the research achievements and progress of Yunnan tea germplasm resource in past sixty years are systematically reviewed from the following aspects:exploration,collecting,conservation,protection,identifi... In this paper,the research achievements and progress of Yunnan tea germplasm resource in past sixty years are systematically reviewed from the following aspects:exploration,collecting,conservation,protection,identification,evaluation and shared utilization.Simultaneously,the current problems and the suggestions about subsequent development of tea germplasm resources in Yunnan were discussed,including superior and rare germplasm collection,tea genetic diversity research,biotechnology utilization in tea germplasm innovation,super gene exploration and function,the construction of utilization platform,biological base of species and population conservation. 展开更多
关键词 yunnan Tea germplasm resource Documentation Concordance SHARING UTILIZATION
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Difference Analysis on Contents of Gallic Acid and Catechins of Tea Resources from Yunnan Province 被引量:3
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作者 罗向前 王家金 +6 位作者 孙雪梅 李友勇 刘本英 汪云刚 宋维希 马玲 周玉忠 《Agricultural Science & Technology》 CAS 2012年第12期2502-2506,2614,共6页
[Objective] This study aimed to analyze the difference in the contents of gallic acid and catechins of tea resources from Yunnan Province. [Method] By using high performance liquid chromatography (HPLC), the content... [Objective] This study aimed to analyze the difference in the contents of gallic acid and catechins of tea resources from Yunnan Province. [Method] By using high performance liquid chromatography (HPLC), the contents of gallic acid (GA), catechins (C), epicatechin (EC), epigallocatechin (EGC), epicatechin gallate (ECG) and epigallocatechin gallate (EGCG) of 121 tea germplasms from the China National Germplasm Tea Repositories (CNGTR) at the Tea Research Institute of Yunnan Academy of Agricultural Sciences (TRIYAAS) were measured. [Result] The content of GA ranged from 0.210% to 1.902%, with an average of 0.834%, explaining rela- tively low GA content among tea germplasms. The content of C ranged from 0.069% to 8.865%, with an average of 1.916%. The content of EC ranged from 0.126% to 2.865%, with an average of 1.112%. The content of EGC ranged from 0.00% to 3.709%, with an average of 0.954%. The content of ECG ranged from 0.739% to 8.957%, with an average of 4.063%. The content of EGCG ranged from 0.819% to 11.77%, with an average of 5.939%. The content of total C ranged from 6.354% to 22.654%, with an average of 14.042%. [Conclusion] There was relatively big difference of catechin contents among different tea resources, indicating that there was plentiful biodiversity of Yunnan tea germplasms. At the same time, three tea germplasms with high epigallocatechin gallate content (≥10%) was selected preliminarily, which would provide important materials for breeding tea cultivars with high EGCG content in the future. 展开更多
关键词 yunnan Province Tea germplasm Gallic acid CATECHINS DIFFERENCE
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