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Tropical deciduous forest in Yunnan,southwestern china:Implications for geological and climatic histories from a little-known forest formation

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Plant Diversity 2021年第6期43卷 444-451页

作者： Hua Zhu Peter Ashton Bojian Gu Shisun Zhou Yunhong Tan Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303PR China Arnold Arboretum Harvard University and Royal Botanic GardensKewUK

In the southern mountain ranges of Yunnan province,china,deep valleys of several large rivers create rain shadows with hot dry summers,and are locally designated tropical;towards the north,notably in the Lancang(Upper Mekong)valley,these regions may experience frost during *** woody forest canopy of these valleys is predominantly deciduous,with evergreen elements in the north,where the canopy is open and the forest ***,we here present tall forest with a closed deciduous canopy and semi-evergreen subcanopy observed in hot dry valleys of these rivers and their tributaries in the tropical *** structure and physiognomy of these forests resemble the tall(moist)deciduous forest formation widespread in South Asia and ***,these forests are largely composed of tropical elements at both the generic(80%)and the species level(>70%),indicating that these forests are indeed *** originally hypothesized that these isolated forests represent refugia of a pre-Holocene extension of tall(moist)deciduous forest formation of South Asia and *** sample plot we established to test this hypothesis confirmed that these forests share the structure and physiognomy of the tall(moist)deciduous forest formation;however,the plots also showed that these forests lack the characteristic and dominant species of the formation's Indo-Burmese *** tree flora,in particular,indicates that both deciduous and evergreen elements are instead mostly derived from the adjacent tropical semi-evergreen forests of tropical southern china;yet they also include an important endemic element,which implies that these forests have survived as refuges possibly since the *** exceptional representation of evergreen elements in these forests indicates that they have rarely been subject to hot fires or domestic cattle browsing,adding to the unique nature of the forests and further justifying their strict conservation.

关键词： Floristic composition Physiognomy Biogeography Independent species assembly Tall deciduous forest southwestern china

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Geochemical Characteristics and Zonation of Primary Halos of Pulang Porphyry Copper Deposit,Northwestern Yunnan Province,southwestern china

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Journal of china University of Geosciences 2008年第4期19卷 371-377页

作者：陈永清黄静宁梁贞 School of the Earth Sciences and Resources China University of Geosciences

The Pulang （普朗） porphyry copper deposit, located in the southern segment of the Yidun-Zhongdian （义敦-中甸） island arc ore-forming belt of the Tethys-Himalaya ore-forming domain, is a recently discovered large copper deposit. Compared with the composition of granodiorite in china, the porphyry rocks in this area are enriched in W, Mo, Cu, Au, As, Sb, F, V, and Na2O （K1≥1.2）. Compared with the composition of fresh porphyry rocks in this district, the mineralized rocks are enriched in Cu, Au, Ag, Mo, Pb, Zn, W, As, Sb, and K2O （K2≥1.2）. Some elements show clear anomalies, such as Zn, Ag, Cu, Au, W, and Mo, and can be regarded as pathfinders for prospecting new ore bodies in depth. It has been inferred from factor analysis that the Pulang porphyry copper deposit may have undergone the multiple stages of alteration and mineralization：（a） Cu-Au mineralization; （b） W-Mo mineralization; and （c） silicification and potassic metasomatism in the whole ore-forming process. A detailed zonation sequence of indicator elements is obtained using the variability index of indicator elements as follows： Zn→Ag→Cu→Au→W→Mo. According to this zonation, an index such as （Ag＊Zn）D/（Mo×W）D can be constructed and regarded as a significant criterion for predicting the Cu potential at a particular depth.

关键词： Pulang porphyry copper deposit zonation of primary halo assessment of Cu potential at depth Tethys-Himalaya ore-forming domain southwestern china

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The influence of urbanization on karst rivers based on nutrient concentration and nitrate dual isotopes： an example from southwestern china

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Acta Geochimica 2017年第3期36卷 446-451页

作者： Zhong-Jun Wang Fu-Jun Yue Jie Zeng Si-Liang Li State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081 China University of Chinese Academy of Sciences Beijing 100049China Puding Karst Ecosystem Research Station Institute of Geochemistry Chinese Academy of Sciences Anshun 562100 China School of Geographical and Earth Sciences University of Glasgow Glasgow G12 8QQ UK Key Laboratory of Karst Environment and Geohazard Ministry of Land and Resources Guizhou UniversityGuiyang 550025 China Institute of Surface-Earth System Science Tianjin University Tianjin 300072 China State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 300072 China

china is experiencing rapid urbanization that has changed the water quality of rivers, especially nutrient loads. In this study, a typical urban river located in a karst area, Chengguan River, was chosen to explore the influence of urbanization on river ecosystems based on nutrient concentration and nitrate isotopes. The results show monthly variability of water chemistry and nutrient concentration. Nutrient concentration in two tributaries and the mainstem showed significant spatial variability, with heavy N and P pollution in one tributary near a suburban area,indicating a response to different levels of *** of nitrate dual isotopes suggest thatvolatilization, assimilation, nitrification, and denitrification all occur in the polluted river. Water chemistry and nitrate isotopes show that major nitrogen sources included domestic waste and agricultural input, such as chemical fertilizer and manure. The results suggest that urbanization increases nutrient concentrations and accelerates the riverine nitrogen dynamic, and point to the need to manage point sources of sewage effluents to improve the water quality of urban rivers in southwestern china.

关键词： Urbanization Urban river Nitrate isotopes southwestern china Chengguan River

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Early Cretaceous dinosaur and other tetrapod tracks of southwestern china

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Science Bulletin 2016年第13期61卷 1044-1051页

作者： Lida Xing Martin G.Lockley State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences School of the Earth Sciences and Resources China University of Geosciences Dinosaur Trackers Research Group University of Colorado Denver

In recent years the Lower Cretaceous red beds of southwestern china have yielded more than 20 significant dinosaur-dominated tracksites. More than half occur in the Jiaguan Formation with the remainder in the Feitianshan and Xiaoba formations. Collectively these sites provide evidence of at least 13 distinct dinosaurian trackmaker morphotypes, in addition to two avian theropod(bird)morphotypes and pterosaur and turtle tracks. Together these total 17 morphotypes provide a data base of 479 potential trackmakers, probably representing the same number of individuals. Such an ichnological database provides a useful proxy paleoecological census of tetrapod communities in the area during the Early Cretaceous, and is especially significant given the complete absence or scarcity of skeletal remains reported from these *** composition of ichnofaunas in all three formations is heavily saurischian(theropod and sauropod) dominated with a high diversity of distinctive theropod morphotypes,mostly assignable to known ichnogenera. Moreover, ichnofaunal data from multiple sites are generally consistent between sites and an indication of the reliability and repeatability of track census data. Such regionally-widespread data are rapidly superseding the information available from the skeletal record in the corresponding area, and must therefore be considered of high paleontological value.

关键词： Early Cretaceous - Dinosaur tracks southwestern china Paleoecology

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The challenge of soil loss control and vegetation restoration in the karst area of southwestern china

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International Soil and Water Conservation Research 2020年第1期8卷 26-34页

作者： Ligang Zhou Xiangdong Wang Zhaoyan Wang Xiaoming Zhang Cheng Chen Huifang Liu State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Research and Hydropower ResearchBeijing100048China Research Center of Water and Soil Conservation Ecological Engineering and Technology Beijing100048China

Soil loss, both from surface soil loss and subsurface soil leakage, in the karst regions of southwestern china is a serious environmental problem that threatens sustainability in that region. The surface soil loss has been extensively studied, and many studies have been conducted to investigate the causes, impacts and mechanisms involved, but the study of subsurface soil leakage has received little attention due to the difficulties in studying the natural conditions. There is no consensus on the overall proportions between surface soil loss and subsurface soil leakage. To control soil loss, improve ecological restoration, and help locals out of poverty, the Chinese government carried out a series of ecological restoration projects in the karst regions of southwestern china starting in the 1980s. As a result, the intensity and areal extent of soil loss continues to decrease and the ecological situation is steadily improving. However, because of the fragile ecosystem in the karst regions, the soil loss control is a long-term task, and the soil loss in some karst regions continues to be a problem. Subsequently, we put forward some suggestions for the policy makers relative to conservation of soil loss and vegetation restoration. These suggestions include:(1) government, private organizations and individuals are encouraged to raise funds for soil loss control and vegetation restoration;(2) nature reserves should be established to increase biodiversity;(3) engineering projects such as small reservoirs, ponds, and flow diversion channels should be constructed in marginal karst regions.

关键词： Karst Soil loss Vegetation restoration southwestern china

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Divergent effects of climate change on cropland ecosystem water use efficiency at different elevations in southwestern china

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Journal of Geographical Sciences 2022年第8期32卷 1601-1614页

作者： TAO Jian ZHU Juntao ZHANG Yangjian DONG Jinwei ZHANG Xianzhou School of Public Administratio n Shand ong Tech no logy and Business UniversityYantai 264005ShandongChina Nagqu Alpine Grassland Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China

Understanding climatic effects on cropland water use efficiency at different elevations is imperative for managing agricultural water and production in response to ongoing climate change in climate-sensitive areas with complex topography, such as southwestern china. We investigated climatic effects on cropland water use efficiency in southwestern china at each 100-m elevation bin during 2001–2017. The maximum water use efficiency was 1.71 gC kg^(–1) H_2O for the 1900–1999 m elevation bin under the growing season temperature and precipitation of 14.58±0.32℃ and 965.40±136.45 mm, respectively. The water use efficiency slopes were dominated by the evapotranspiration slopes at elevations below 1999 m but were controlled by the gross primary productivity slopes at elevations above 2000 m. This difference was caused by the substantial responses of evaporation to climate change at lower elevations and the increased climatic sensitivity of gross primary productivity at higher elevations. In comparison to those at other elevations, croplands at lower elevations were more vulnerable to extreme drought because of the dominant role fluctuating evapotranspiration played in water use efficiency. The findings will improve cropland water management in the study area.

关键词： cropland water use efficiency southwestern china elevational gradient

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Fossil seeds of Euryale(Nymphaeaceae) indicate a lake or swamp environment in the late Miocene Zhaotong Basin of southwestern china

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Science Bulletin 2015年第20期60卷 1768-1777页

作者： Yongjiang Huang Xueping Ji Tao Su Li Wang Chenglong Deng Wenqi Li Hongfen Luo Zhekun Zhou Key Laboratory for Plant Biodiversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences Yunnan Institute of Cultural Relics and Archaeology and Research Center for Southeast Asian Archeology Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Zhaotong Institute of Cultural Relics Zhaoyang Museum

Euryale （Nymphaeaceae） is a monotypic genus distributed in eastern Asia, but fossils in its native distribu- tion are sparse as compared to Europe where the genus has disappeared. Here, we describe a new fossil species, Euryale yunnanensis sp. nov., from the late Miocene Zhaotong Basin in southwestern china on the basis of seed remains. Char- acteristics including an ellipsoidal to almost spherical shape, a smooth surface, a germination cap that covers the micro- pyle, the separation of the hilum and germination cap （mi- cropyle）, elliptic testa surface cells with undulate margins and thickened cell walls collectively indicate a close affinity with the genus Euryale in Nymphaeaceae. Comparisons of seed morphology and anatomy demonstrate that the newly described fossil species differs from modem and other fossil species of Euryale and thus verify the assignment to a new fossil species. As the modem Euryale is an aquatic plant, preferably living in swamps and lakes with shallow and stable water, we hypothesize that a lake and/or swamp environment with shallow water was present near Shui- tangba in the Zhaotong Basin, where the Shuitangba homi- noid lived during the late Miocene. This inference is generally consistent with paleoenvironmental data extracted from avian, fish, frog, turtle and crocodile fossils, as well as from aquatic pollen. The fossil history suggests a compara- tively recent （Miocene） emergence of Euryale, which is roughly in agreement with the divergence time inferred from the molecular information.

关键词： Euryale Nymphaeaceae Aquatic Late Miocene Zhaotong Basin southwestern china

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Zircon SHRIMP U-Pb geochronology,geochemistry and petrogenesis of the upper Eocene Shuangmaidi peraluminous granite in Baoshan Block,Western Yunnan Terrain,southwestern china

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Science china Earth Sciences 2011年第7期54卷 982-997页

作者： HUANG JingNing CHEN YongQing ZHAI XiaoMing LU YingXiang XIE YongFu CHENG ZhiZhong School of Earth Science andMineral Resources China University ofGeosciences Beijing 100083 China College of Lake County 19351 W. Washington St Grayslake IL 60030 USA Yunnan Geological Survey Kunming 650051 China Baoshan Branch Company Yunnan Company of Mineral Resources Baoshan 678000 China Institute of Exploration Geophysics and Geochemistry Chinese Academy of Geological Sciences Langfang 065000 China The Geological Museum of china Beijing 100034 China

The Baoshan Block is tectonically located in the middle segment of the Sibumasu plate. Granitic magmatism within the Baoshan Block has been considered weakly active due mainly to very limited exposures during the Himalaya orogenic episode. The geochronological study on the buried Shuangmaidi granite has confirmed the existence of the Cenozoic granitoids in the Baoshan Block. The present study indicates that：（1） It is medium- to coarse-grained two mica phyric granite, characterized by high SiO2 （73.55%-77.16%） and low CaO （0.34%-1.38%） contents, with a total alkalis （K2O＋Na2O） of 5.22%-8.03%, K2O/Na2O ratios of 0.24-1.79, and total rare earth elements （ZREE） of the granite between 85 and 125 ppb. All samples are enriched in light REE and exhibit medium negative Eu anomalies; and they show pronounced negative anomalies in Ba, Sr, Ti, and Nb but significant positive anomalies in K, Rb, U, Th, and Pb on mantle-normalized trace element patterns, indicating typi-cally peraluminous to strongly peraluminous S-type granite. （2） The zircon SHRIMP U-Pb ages of the granite are 36.27±0.48 Ma for the samples from ZK7-1 and 35.78±0.49 Ma for those from ZK0-1, respectively. The similar zircon ages from these two drill cores may suggest that the granite samples come from the same buried pluton. （3） 206pb/204pb values of the granite vary from 20.115 to 25.359, 207pb/204pb from 15.776 to 16.160, and 208pb/204pb from 39.236 to 41.285, showing the characteristics of radio- active lead anomaly of the upper crust. The （87Sr/86Sr）i values calculated on the average age of the two-mica orthoclase granite （36 Ma） range from 0.72524 to 0.77503 and eNd（t） values vary from -10.9 to -11.7. These data, along with the depleted-mantle Nd modal ages of 1.73-1.80 Ga, imply that the granites might have formed from partial melting of the Precambrian crystal basements. （4） On the Hf-Rb-Ta diagram, almost all the samples fall within the field of post-collision tectonic setting. The CaO/Na2O and A1203/TiO

关键词： Upper Eocene peraluminous granite elements and Sr-Nd-Pb isotopic geochemistry Himalayan post-collision orogenic setting Baoshan Block southwestern china

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Causes and Predictability of the 2021 Spring southwestern china Severe Drought

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Advances in Atmospheric Sciences 2022年第10期39卷 1766-1776页

作者： Yunyun LIU Zeng-Zhen HU Renguang WU Xing YUAN CMA Climate Studies Key Laboratory National Climate CenterChina Meteorological AdministrationBeijing 100081China Key Laboratory of Meteorological Disaster Ministry of Education&Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science&TechnologyNanjing 210044China Climate Prediction Center NCEP/NOAACollege ParkMaryland 20740USA School of Earth Sciences Zhejiang UniversityHangzhou 310058China School of Hydrology and Water Resources Nanjing University of Information Science and TechnologyNanjing 210044China

In the spring of 2021,southwestern china(SWC)experienced extreme drought,accompanied by the highest seasonal-mean temperature record since *** drought event occurred in the decaying phase of a La Niña event with negative geopotential height anomalies over the Philippine Sea,which is distinct from the historical ***,spring drought over SWC is often linked to El Niño and strong western North Pacific subtropical ***,we show that the extreme drought in the spring of 2021 may be mainly driven by the atmospheric internal variability and amplified by the warming ***,the evaporation increase due to the high temperature accounts for about 30%of drought severity,with the contributions of its linear trend portion being nearly 20%and the interannual variability portion being about 10%.Since the sea surface temperature forcing from the tropical central and eastern Pacific played a minor role in the occurrence of drought,it is a challenge for a climate model to capture the 2021 SWC drought beyond one-month lead times.

关键词： extreme spring drought southwestern china precipitation evaporation warming trend internal variability predictability

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Influence of transboundary air pollution on air quality in southwestern china

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Geoscience Frontiers 2021年第6期12卷 114-128页

作者： Xiufeng Yin Shichang Kang Maheswar Rupakheti Benjamin de Foy Ping Li Junhua Yang Kunpeng Wu Qianggong Zhang Dipesh Rupakheti State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of ScienceLanzhou 730000China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100039China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100085China Institute for Advanced Sustainability Studies PotsdamGermany Department of Earth and Atmospheric Sciences Saint Louis UniversitySt.LouisMO 63108USA Northwest Institute of Eco-Environment and Resources Chinese Academy of ScienceLanzhou 730000China Institute of International Rivers and Eco-Security Yunnan UniversityKunming 650091China

Air pollution is a grand challenge of our time due to its multitude of adverse impacts on environment and society,with the scale of impacts more severe in developing countries,including ***,china has initiated and implemented strict air pollution control measures over last several years to reduce impacts of air *** data from Jan 2015 to Dec 2019 on six criteria air pollutants(SO_(2),NO_(2),CO,O_(3),PM_(2.5),and PM_(10))at eight sites in southwestern china were investigated to understand the situation and analyze the impacts of transboundary air pollutants in this *** terms of seasonal variation,the maximum concentrations of air pollutants at these sites were observed in winter or spring season depending on individual *** diurnal variation,surface ozone peaked in the afternoon while the other pollutants had a bimodal pattern with peaks in the morning and late *** was limited transport of domestic emissions of air pollutants in china to these *** emissions enhanced the concentrations of air pollutants during some pollution ***,the transboundary transport of air pollution from South Asia and Southeast Asia was associated with high concentrations of most air pollutants observed in southwestern *** air pollutants can be transported to southwestern china over long distances from the source regions,it is necessary to conduct more research to properly attribute and quantify transboundary transport of air pollutants,which will provide more solid scientific guidance for air pollution management in southwestern china.

关键词： Air pollutants Transboundary transport southwestern china

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