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A New Eosauropterygian(Diapsida:Sauropterygia) from the Middle Triassic of Luoping,yunnan Province

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Journal of Earth Science 2012年第1期23卷 33-40页

作者： Long Cheng Xiaohong Chen Xiongwei Zeng Yongjian Cai Key Laboratory of Biogeology and Environmental Geology of Ministry of Education China University of GeosciencesWuhan 430074China Wuhan Institute of Geology and Mineral Resources Wuhan 430223China Wuhan Institute of Earthquake Engineering Wuhan 430071China

A new eosauropterygian, Largocephalosaurus polycarpon gen. et sp. nov., was described based on a skeleton from the Middle Triassic of Luoping （罗平）, Ynnnan （云南） Province, southwestern China. The new taxon is characterized by a big skull, paired frontal, laterally expanded upper temporal fossa, anterior process of squamosal entering orbit, robust teeth with basally expanded crown and blunt tip, short cervical region, distinctly elongated transverse process of the dorsal vertebrae, short and broad dorsal ribs, stout gastralia, scapula with distinctly posterodorsally extending blade, distinctly robust humerus, eleven carpal ossifications, and a manual fomula of 2-3-4-5-5. A phylogenetic analysis suggests that Largocephalosaurus is the basal-most member of a clade including Wumengosaurus, European pachypleurosaurs, and Nothosauroidea.

关键词： yunnan Triassic Guanling Formation Sauropterygia.

A DISCUSSION ON BIOGEOGRAPHICAL LINES OF THE TROPICAL SUBTROPICAL yunnan

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Chinese Geographical Science 2002年第1期12卷 91-97页

作者： ZHU Hua, YAN Li chun(Kunming Division of Xishuangbanna Tropical Botanical Garden, the Chinese Academy of Sciences, Kunming 650223, P.R.China) Kunming Division of Xishuangbanna Tropical Botanical Garden the Chinese Academy of Sciences Kunming P. R. China

Based on comparative studies on four regional floras from northwest, west, south and southeast of yunnan respectively, the formerly suggested two biogeographical lines, i.e. the “Tanaka Line" and the “Ecogeographical Diagonal Line", both going from northwest to southeast of yunnan, and their significance are discussed. In family and generic levels, similarity coefficients among the four compared floras are more than 93% and 60% separately, which indicate the close floristic affinities among them. The highest similarity coefficient, i.e. 98.7% in family level and 78.6% in generic level separately, is found between the regional flora of northwest yunnan and the flora of southeast yunnan although these two regions are the most distant away each other among the compared regional floras. The flora of northwest yunnan is also the most similar to the flora of southeast yunnan in floristic composition. These support the idea of “Ecogeographical Diagonal Line". In specific level, the relatively high similarity coefficient is between the regional flora of west yunnan and the one of south yunnan. The floristic affinities among these regional floras and some distribution patterns could be explained by the geological history and tectonic theory of yunnan.

关键词： biogeographical lines floristic affinity yunnan

The Dynamic Mechanisms for the Formation of Primary Metal Zoning of Cassiterite-Sulfide Deposits in the Gejiu Metallogenic Province, yunnan

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Acta Geologica Sinica(English Edition) 1991年第1期65卷 51-63页

作者： Yu Chongwen Jiang Yaosong China University of Geosciences, Beijing China University of Geosciences Beijing

Copper and tin in cassiterite-sulfide deposits of the Gejiu metallogenic province are intimately associatedand show peculiar primary metal zoning. The authors made use of computer techniques to simulatenumerically the zoning of these ore deposits. The study shows that the regular spatial zoning probably resultedfrom the succession of multiple, intermittent and pulsatory mineralizations, The successive transports with di-verse velocities along channelways of the ore-forming solutions, taking place under conditions of definite dif-ference between metal concentrations, in solutions and wallrocks, followed by differential deposition, consti-tute possible dynamic mechanisms for the primary metal zoning.

关键词： Met rate The Dynamic Mechanisms for the Formation of Primary Metal Zoning of Cassiterite-Sulfide Deposits in the Gejiu Metallogenic Province yunnan

An Evaluation of the Introduction of Modified Cropping Practices in yunnan Province,China,Using Surveys of Farmers’ Households

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Agricultural Sciences in China 2009年第2期8卷 188-202页

作者： M Subedi T J Hocking M A Fullen A R McCrea E Milne D J Mitchell WU Bo-zhi School of Applied Sciences University of Wolverhampton Wulfruna Street Wolverhampton WV1 1LY UK The Macaulay Institute Craigiebuckler Aberdeen AB15 8QH UK yunnan Agricultural University Kunming 650201 P.R.China

Problems associated with land degradation are serious in China. Sloping land in South China has experienced a decline in crop productivity by 30-60% due to soil erosion and it has been predicted that most topsoil will be lost within the next 100 years if current erosion rates continue. Considering these situations, an agro-environmental research and development project （Sustainable Highland Agriculture in South-East Asia- SHASEA） was conducted in a catchment in yunnan Province, China, to address the objectives of increasing crop productivity in sustainable and environmentally-friendly ways. A range of cropping practices was developed and implemented in a rural upland catchment （Wang Jia）. At the end of the project, farmers were surveyed to evaluate project effectiveness. All farmers from Wang Jia Catchment, who were involved in project implementation, were surveyed. A sample of farmers working in an adjacent catchment （not associated with the project） was surveyed for comparative purposes. Farmers had different perceptions of the cropping practices employed. Contour cultivation was preferred and likely to be adopted. Others practices such as straw mulching and intercropping were seen as less appropriate and unlikely to be adopted. Polythene mulch was recognized as effective, but likely to be adopted only if financial returns were favourable. The availability of relevant information had an important impact on the extent of technology testing by farmers and their willingness to adopt the practices in the future.

关键词： cropping practices farmers' perceptions household survey yunnan China

Surrogacy of bird species in systematic conservation planning and conservation assessments in yunnan Province,China

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Journal of Mountain Science 2022年第10期19卷 2861-2873页

作者： ZHOU Jian YANG Fei-ling ZHONG Zi-jie ZHANG Ji LENG Xian YE Jin WU Rui-dong Conservation Biogeography Research Group Institute of International Rivers and Eco-securityYunnan UniversityKunming 650091China yunnan Key Laboratory of International Rivers and Transboundary Eco-security Yunnan UniversityKunming 650091China

Bird diversity is often used as surrogates for other species diversity,but there is a limited understanding of the extent of this surrogate in identifying representative priority conservation areas(PCAs).We used yunnan Province in China as a case to measure the surrogacy of birds in systematic conservation ***,we collected distribution records of mammals,amphibians,reptiles,and birds from public databases and literature,and applied systematic conservation planning methods to identify *** targeted four taxonomic groups at conservation targets of 17%,31%,and 50%of the total study area,and used the Jaccard similarity index to evaluate the surrogate extent of bird PCAs for the other three ***,we overlapped different portfolios of PCAs with six categories of protected areas(PAs)in yunnan,calculated the protection rates,and evaluated the effect of sustainable-use PAs on improving the protection rate of strict Nature *** results showed that bird PCAs generally had the highest surrogacy for representing PCAs of the other three *** the 50%conservation target,the Jaccard indices between birds and the other taxa reached about ***,amphibian PCAs had a good surrogacy for conserving reptiles,with a Jaccard index of 0.30,0.44 and 0.51 at the 17%,31%and 50%conservation targets,*** existing PA system had quite low coverages for PCAs of these four taxa,and the average protection rates were 22.97%,19.78%and 16.52%at the three levels of conservation targets,*** sustainable-use PAs can greatly complement the strict Nature Reserves by achieving average increased PA coverages of 10.00%,9.20%and 7.90%at the three conservation *** findings provide a basis for surrogate-based conservation planning for areas with insufficient biodiversity information.

关键词： Biodiversity surrogates Priority conservation areas Protected areas Systematic conservation planning Threatened species yunnan

Coping with Pressures of Modernization by Traditional Farmers: a Strategy for Sustainable Rural Development in yunnan, China

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Journal of Mountain Science 2007年第1期4卷 57-70页

作者： SHIRO Chikamatsu Jose Ireneu Furtad SHEN Lixin YAN Mei Imperial College London London SWT 2AZ England U.K. yunnan Academy of Forestry Kunming 650204 China Asian Institute of Management Manila Philippines

Traditional farming practices conform to sustainable rural livelihoods, while agricultural modernisation tends to undermine these practices through various perturbations. A case study in Tengchong County (western yunnan, China) shows that transformation of traditional alder (Alnus nepalensis) and dry rice (upland rice) rotational farming to introduced Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) plantations leads to localised water scarcity and soil fertility decline. While farmers are aware of ecological sustainability of traditional farming, they prefer Chinese fir forestry because it is less labour-intensive, has a high market value, and releases time for profitable off-farm work. Farmers adapt to economic liberalization by planting high value crops and trees. However, alternatives to make local agricultural production more profitable through competitive business strategies, cooperative approaches, innovations in integrating high value crops and 'downstream' processingfor sustainable rural livelihoods have been overlooked largely due to poor information availability and lack of organisational framework.

关键词： Agrobiodiversity sustainable rural development capital assets traditional knowledge tra-ditional fanning yunnan alderupland rice Chinese fir

The role of aerial algae in the formation of the landscape of the yunnan Stone Forest,yunnan Province, China

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Science China Earth Sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3, ZHANG Jie2, SONG Linhua1 & BAO Haosheng2 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2. Department of Geography, Nanjing University, Nanjing 210093, China 3. School of Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Department of Geography Nanjing University Nanjing 210093 China School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, yunnan Province, China, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (<10-3m) and minor-scale (10-3-10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, yunnan Province, China.

Chemical compositions of sulfides in the porphyry Cu ores,Yangla Cu deposit,yunnan,China:implication for ore genesis

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Acta Geochimica 2020年第6期39卷 947-972页

作者： Xinfu Wang Bo Li Zuopeng Xiang Yan Yue Guo Tang Faculty of Land and Resource Engineering Kunming University of Science and TechnologyKunming 650093China Kunming Prospecting Design Institute of China Nonferrous Metals Industry Co. LtdKunming 650051China

The Yangla Cu deposit is the largest ore deposit in the Jinshajiang polymetallic metallogenic belt,northwest yunnan,*** is no consensus on the genesis of the ore deposit owing to the limited studies on the chemical compositions of *** study used an electron probe micro-analyzer to constrain the chemical compositions of pyrite,chalcopyrite,molybdenite,and sphalerite in the porphyry Cu ore of the Yangla Cu deposit and compared them with the chemical compositions of sulfides in the skarn Cu *** trace element contents and their occurrences were used to estimate the metallogenic temperature and infer the genesis of the Yangla *** results show that the sulfides in the porphyry Cu ores have variations of ore element concentrations relative to their theoretical *** is depleted in S but elevated in Fe;chalcopyrite is depleted in Cu,Fe,and S;and molybdenite and sphalerite are enriched in S whilst depleted in Mo and *** concentrations of the main metallogenic elements Cu,Fe,Mo,Zn,and S in the porphyry are generally lower than those in skarn,suggesting that the porphyry ore was formed in a moderate to moderate-high temperature metallogenic *** formation time may also be slightly later than that of the skarn Cu *** such as As,Co,***,Zn,Mo,Cd,and Ni mainly exist as isomorphic replacements and mineral inclusions in the sulfides of both porphyry and skarn Cu *** trace element features of sulfides in the two ore bodies show that the Yangla Cu deposit may be a composite super imposed ore deposit,and让s formation has undergone the process of exhalative-sedimentary to skarnporphyry mineralization.

关键词： Sulfides Trace elements Chemical composition Yangla Cu deposit yunnan

Palaeomagnetic Study on the Precambrian-Cambrian Boundary Candidate Stratotype Section at Meishucun, yunnan

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Acta Geologica Sinica(English Edition) 1991年第1期65卷 97-108页

作者： Liang Qizhong Fang Wu Rob Van der Voo yunnan Institute of Geological Science, Kunming,yunnan Department of Geological Sciences,University of Michigan,Ann Arbor, MI.48109-1063, U.S.A. Liu Linqun yunnan Institute of Geological Scienc Kunming Yunnan China

The Meishucun secton has been recommended as an international candidate stratotype secton of thePrecambrian-Cambrian boundary. The paper deals with the palaeomagnetic study on the section. A total of159 palaeomagnetic samples were successively collected from the platform-facies sequence of carbonates andphosphates at the section. Thermal demagnetization results indicate a great majority of the rocks at the sectionhave been strongly overprinted by recent magnetic field, but 57 samples have preserved remanentmagnetization with antipodal directions (mean D/I=4.2°/ 7.1°, K=9, α_(95) = 6.6°). Baaed on calculation,the location of the palaeomagnetic pole was at 68.8°N and 270.7°E, which is different from any palaeopolesobtained from younger Phanerozoic rocks in South China. The results reveal a polarity zonation which in-cludes at least 9 reversal events. A comparison of China's magnetostratigraphic records with those fromSiberia, Australia and the western U.S.A. shows that all the sections are characterized by frequent polarity re-versals.

关键词： yunnan Palaeomagnetic Study on the Precambrian-Cambrian Boundary Candidate Stratotype Section at Meishucun