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Abandoned land identification in karst mountain area based on time series SAR characteristics at geo-parcels scale

山地科学学报（英文） 2023年第3期20卷 792-809页

作者： ZHOU Zhong-fa WANG Ling-yu CHEN Quan LUO Jian-cheng ZHAO Xin ZHANG Shu ZHANG Wen-hui LIAO Juan LYU Zhi-jun School of Karst Science Guizhou Normal UniversityGuiyang 550001China Key Laboratory of natural resources Monitoring in Tropical and Subtropical Area of South China Ministry of Natural ResourcesGuangzhou 510670China Department of Information Engineering Guizhou Institute of Light IndustryGuiyang 550001China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100101China Hengyang Normal University Hengyang 421000China

Mapping abandoned land is very important for accurate agricultural ***,in karst mountainous areas,continuous high-resolution optical images are difficult to obtain in rainy weather,and the land is fragmented,which poses a great challenge for remote sensing monitoring of agriculture *** this study,a new method for identifying abandoned land is proposed:firstly,a few Google Earth images are used to transform arable land into accurate vectorized geo-parcels;secondly,a time-series data set was constructed using Sentinel-1A alpha parameters for 2020 on each farmland geoparcel;thirdly,the semi-variation function(SVF)was used to analyze the spatial-temporal characteristics,then identify abandoned *** results show:(1)On the basis of accurate spatial information and boundary of farmland land,the SAR time-series dataset reflects the structure and time-series *** land with an accuracy of 80.25%.The problem of remote sensing monitoring in rainy regions and complex surface areas is well-resolved.(2)The spatial heterogeneity of abandoned land is more obvious than that of cultivated land within *** step size for significant changes in the SVF of abandoned land is shorter than that of cultivated land.(3)The SVF time sequence curve presented a strong peak feature when farmland was *** reveals that the internal spatial structure of abandoned land is more disordered and *** showed that time-series variations of spatial structure within cultivated land have broader applications in remote sensing monitoring of agriculture in complex imaging environments.

关键词： Sentinel-1 SAR Abandoned farmland Semi variogram function Farmland geo parcel Time seriescharacteristics Texture feature Karst mountainous area

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Evidence of hybridization of cattle and aurochs on the Tibetan Plateau3750 years ago

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Science Bulletin 2024年第18期69卷 2825-2828页

作者： Shungang Chen Lele Ren Yu Gao Guanghui Dong Guilian Sheng Jianlin Han Xinyi Liu Ningbo Chen Fahu Chen Group of Alpine Paleoecology and Human Adaptation(alpha) Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China School of History and Culture Lanzhou UniversityLanzhou 730000China Key Laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China School of Environmental Studies China University of GeosciencesWuhan 430078China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430078China Yazhouwan National Laboratory Sanya 572024China Department of Anthropology Washington University in St.LouisSt.Louis MO 63130USA Key Laboratory of Animal Genetics Breeding and Reproduction of Shaanxi ProvinceCollege of Animal Science and TechnologyNorthwest A&F UniversityYangling 712100China

Wild aurochs(Bos primigenius)were once widespread across Eurasia and North Africa but became extinct around the 17th century[1].Aurochs are considered the ancestor of modern taurine(*** taurus)and indicine(***)cattle,which were independently domesticated within regions restricted to Southwest Asia and South Asia,respectively[2,3].Extensive gene flow from local aurochs to domestic cattle has been well documented in Southwest Asia,Europe,and Africa[3,4],raising questions about the mechanisms underlying both the domestication and dispersal of early cattle.

关键词： B.t Wild Plateau

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环太平洋特大干旱导致公元1644年明朝首都的陷落（英文）

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Science Bulletin 2024年第19期 3106-3114页

作者：陈峰王涛赵晓恩 Jan Esper Fredrik Charpentier Ljungqvist Ulf Büntgen Hans W.Linderholm David Meko 许红娜岳伟鹏王世杰袁玉江郑景云潘威 Fidel Roig Martín Hadad 胡茂魏家昌陈发虎 Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security Institute of International Rivers and Eco-Security Yunnan University Southwest United Graduate School Regional Climate Group Department of Earth Sciences University of Gothenburg Climate Change Research Center and Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Department of Geography Johannes Gutenberg University Global Change Research Institute (Czech Globe) Czech Academy of Sciences Department of History Stockholm University Bolin Centre for Climate Research Stockholm University Swedish Collegium for Advanced Study Linneanum Department of Geography University of Cambridge Department of Geography Faculty of Science Masaryk University Swiss Federal Research Institute (WSL) Laboratory of Tree-Ring Research University of Arizona Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC FEMD) Nanjing University of Information Science and Technology Key Laboratory of Tree-ring Physical and Chemical Research Institute of Desert Meteorology China Meteorological Administration Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Key Laboratory of Digital Human Technology R&D and Application of Yunnan Provincial Department of Education Yunnan University Laboratorio de Dendrocronología e Historia Ambiental IANIGLA-CCT CONICET-Universidad Nacional de Cuyo Hémera Centro de Observación de La Tierra Escuela de Ingeniería Forestal Facultad de Ciencias Universidad Mayor Laboratorio de Dendrocronología de Zonas áridas CIGEOBIO (CONICET-UNSJ) Gabinete de Geología Ambiental (INGEO-UNSJ) alpha State Key Laboratory of Tibetan Plateau Earth System Environment and Resources (TPESER) Institute of Tibetan Plateau Research Chinese Academy of Sciences College of resources and Environment University of Chinese Academy of Sciences MOE Key Laboratory of We

Historical documents provide evidence for regional droughts preceding the political turmoil and fall of Beijing in 1644 CE, when more than 20 million people died in northern China during the late Ming famine period. However, the role climate and environmental changes may have played in this pivotal event in Chinese history remains unclear. Here, we provide tree-ring evidence of persistent megadroughts from1576 to 1593 CE and from 1628 to 1644 CE in northern China, which coincided with exceptionally cold summers just before the fall of Beijing. Our analysis reveals that these regional hydroclimatic extremes are part of a series of megadroughts along the Pacific Rim, which not only impacted the ecology and society of monsoonal northern China, but likely also exacerbated external geopolitical and economic pressures. This finding is corroborated by last millennium reanalysis data and numerical climate model simulations revealing internally driven Pacific sea surface temperature variations and the predominance of decadal scale La Ni?a-like conditions to be responsible for precipitation decreases over northern China,as well as extensive monsoon regions in the Americas. These teleconnection patterns provide a mechanistic explanation for reoccurring drought spells during the late Ming Dynasty and the environmental framework fostering the fall of Beijing in 1644 CE, and the subsequent demise of the Ming Dynasty.

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Dust storms in northern China and their significance for the concept of the Anthropocene

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Science China Earth Sciences 2022年第5期65卷 921-933页

作者： Jianbao LIU Jie CHEN Shengqian CHEN Xinwei YAN Haoran DONG Fahu CHEN Key Laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental ScienceLanzhou UniversityLanzhou 730000China Group of Alpine Paleoecology and Human Adaptation(alpha) State Key Laboratory of Tibetan Plateau Earth SystemResources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

A key scientific issue in the study of the Anthropocene is the determination of the corresponding stratigraphic marker in geological *** arid and semi-arid regions of Asia are the second largest dust source on Earth,and their release,transport and deposition of dust affect global climate change,as well as marine and terrestrial biogeochemical *** the past~2000 years,human activity has outpaced natural climatic variability as the dominant control of dust storms in northern ***,exploring the potential of anthropogenic Asian dust as a marker of the Anthropocene and its impacts on lake ecosystems may contribute to an improved definition of the characteristics and timing of the *** this context,we measured spectrally-inferred chlorophyll a from the sediments of an undisturbed alpine lake in northern China,and compared the results with dust storm data from the same cores and with regional climatic *** dust is a widely distributed,globally significant signal of human activity,and it is also well preserved in various geological archives;hence,we propose anthropogenic dust can be considered as a potential marker of the *** dust signals in stratigraphic records during the past~2000 years differ substantially from those during the early and middle Holocene,which demonstrates that,at least since~2000 years ago,human activity has exceeded the natural forcing of dust transport in northern *** therefore propose that there are spatial and temporal differences in the onset of the Anthropocene,as defined by anthropogenic dust deposition,which is therefore *** spectrally-inferred chlorophyll a record is consistent with dust storm activity over the past~2000 years(except since the 1950s),suggesting that anthropogenic dust storms were the dominant control on lake primary *** to the 1950s the interactions of the East Asian summer monsoon(EASM),human activity,dust storms and lake ecos

关键词： Anthropocene Stratigraphic marker Dust storms Lake primary production Time-transgressive Great Acceleration

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Purification,Characterization and ~1H NMR Resonance Assignment of an α-Like Neurotoxin BmK 16 from the Venom of Chinese Scorpion Buthus martensii Karsch

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Chinese Journal of Chemistry 2003年第10期21卷 1378-1384页

作者：张乃霞吴宫王中华吴厚铭 State Key Laboratory of Bioorganic and natural Products Chemistry

A natural scorpion toxin BmK 16 was purified for the first time from the venom of the Chinese scorpion Buthus martensii Karsch (BmK) by using combined gel filtration, ion exchange and reversed phase chromatography. The sequence of the N terminal 8 amino acid residues was determined by Edman degradation. Using the N terminal sequence as a tag, the database searching revealed a hit in the scorpion cDNA Bank. The sequence for N terminal 8 amino acid residues, molecular weight and amino acid compositions of BmK 16 were identical with the calculated values according to the first 64 residues' sequence of the precursor peptide alpha neurotoxin TX16 derived from the sequence of the cDNA AF156597 (EMBL). The sequence specific resonance assignment of BmK 16 was achieved and the intact sequence of BmK 16 was determined as followings: VRDAY IAKPH NCVYE CARNE YCNDL CTKNG AKSGY CQWVG KYGNG CWCKE LPDNV PIRVP GKCH. Furthermore, the results from the sequence homology analysis and the toxicity assays indicated that BmK 16 was an α like scorpion neurotoxin.

关键词： scorpion toxin Buthus martensii Karsch BmK 16,αlike scorpion neurotoxin amino acid sequence resonance assignment

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Alternating influences of the Westerlies and Indian Summer Monsoon on the hydroclimate of the source region of the Yarlung Tsangpo over past 4000 yr

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Frontiers of Earth Science 2023年第4期17卷 933-944页

作者： Zhe SUN Zirui HUANG Kejia JI Mingda WANG Juzhi HOU Institute of Geography and resources Science Sichuan Normal UniversityChengdu 610066China Group of Alpine Paleoecology and Human Adaptation(alpha) State Key Laboratory of Tibetan Plateau Earth SystemResources and Environment(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of Sciences(CAS)Beijing 100101China School of Geography Liaoning Normal UniversityDalian 116029China

The Yarlung Tsangpo,the longest river in the southern Tibetan Plateau(TP),has attracted much research attention aimed at understanding the factors controlling its modern hydrology and possible future discharge in the context of ongoing climate ***,partly due to the complex regional climatic background,no consistent conclusions have been reached,especially for its upper *** reconstructions of the source region of the Yarlung Tsangpo can potentially improve our understanding of the history of humidity and its response to climatic *** this study,we used a 97 cm gravity core from Gongzhu Co to reconstruct the hydrology change during the late *** core was dated using AMS ^(14)C and Pb/Cs methods,and we used measurements of element contents(determined by high-resolution XRF scanning),grain size,IC/TOC,and magnetic susceptibility to reconstruct hydroclimatic changes in the source of the Yarlung Tsangpo watershed since~4000 yr *** with a modern meteorological data set,we found that PC1 of the XRF data,the Ca/(Fe+Ti)ratio,and EM1 of the grain size data were indicative of changes in *** records demonstrate a wet interval during~4-1.7 ka BP(ka=1000 yr,BP represents years before 1950 AD),followed by a dry period during since~1 ka *** with independent regional paleoclimatic records revealed shifts in the dominant factors controlling *** wet interval during~4-1.7 ka BP was coeval with a strengthened Westerlies,implying a dominant moisture supply from northern high ***,the extremely low values of Ca/(Fe+Ti)ratio during~4-2.5 ka BP indicate potential glacial freshwater source,which is corroborated by the concurrent high magnetic susceptibility values and increased grain *** rapid drying trend during~1.7-1 ka BP suggests a switch in moisture supply from the Westerlies to the Indian Summer Monsoon(ISM).We attribute the drought conditions after~1 ka BP to a weakened ISM,althoug

关键词： late Holocene humidity changes Westerlies ISM Yarluang Tsangpo

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Earliest hand-and footprint art indicates that Denisovans may have occupied the interior of the high-altitude Tibetan Plateau since 200 thousand years ago

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Science China Earth Sciences 2022年第4期65卷 769-772页

作者： Fahu CHEN Huan XIA Zhenxiu JIA Dongju ZHANG Group of Alpine Paleoecology and Human Adaptation(alpha) Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Beijing 100101China MOE Key Laboratory of Western China’s Environmental System Lanzhou UniversityLanzhou 730000China

As a result of rapid uplift since the late Cenozoic, the Tibetan Plateau eventually developed an enormous area(3.08 million km^(2)) and became the highest elevation plateau on Earth. The cold and hypoxic environments of the Tibetan Plateau,combined with the strong solar radiation receipt and lack of biological resources, present a major challenge to the occupation and expansion of humans.

关键词： Tibetan Plateau interior

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A Cool-Arid Climate with Large Temperature Seasonality Implied by Arboreal Pollen in the Early Holocene,North-Central China

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地球科学学刊:英文版 2023年第5期34卷 1629-1631页

作者： Fang Tian Meijiao Chen Qinghai Xu Xianyong Cao College of Resource Environment and Tourism Capital Normal UniversityBeijing 100048China College of Geography Sciences Hebei Normal UniversityShijiazhuang 050024China Group of Alpine Paleoecology and Human Adaptation(alpha) State Key Laboratory of Tibetan Plateau Earth SystemEnvironment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

The climate of the North-Central China during the Early Holocene is still debated,particularly with regard to precipitation,despite various paleoclimate records based on multi proxies and models(Chen et al.,2015;Liu J B et al.,2015;Liu Z Y et al.,2014).The temperature pattern is also uncertain because of a lack of temperature records for north-central *** sequences are still the most abundant paleo-environmental record particularly for north-central China and have the potential to explore the past precipitation and temperature changes,because both precipitation and temperature are essential for plant growth,and the sensitivity to climatic variables varies among different plants(Liang et al.,2020).Quantitative climate reconstructions based on the modern pollen-climate relationship have been widely generated for east Asia,and the results used to explore the spatial-temporal patterns and mechanisms of past climate changes(Chen et al.,2020,2015;Herzschuh et al.,2019).

关键词： China Holocene climate

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Putative Chitin Synthases from Branchiostoma floridae Show Extracellular Matrix-related Domains and Mosaic Structures

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Genomics, Proteomics & Bioinformatics 2012年第4期10卷 197-207页

作者： Gea Guerriero Fungal Genetics and Genomics Unit Department of Applied Genetics and Cell BiologyUniversity of Natural Resources and Life Science ViennaUniversity and Research Center Campus Tulln-TechnopolKonrad Lorenz Strasse 24A-3430 TullnAustria

The transition from unicellular to multicellular life forms requires the development of a specialized structural component, the extracel- lular matrix （ECM）. In Metazoans, there are two main supportive systems, which are based on chitin and collagen/hyaluronan, respec- tively. Chitin is the major constituent of fungal cell walls and arthropod exoskeleton. However, presence of chitin/chitooligosaccharides has been reported in lower chordates and during specific stages of vertebrate development. In this study, the occurrence of chitin syn- thases （CHSs） was investigated with a bioinformatics approach in the cephalochordate Branchiostomafloridae, in which the presence of chitin was initially reported in the skeletal rods of the pharyngeal gill basket. Twelve genes coding for proteins containing conserved amino acid residues of processive glycosyltransferases from GT2 family were found and 10 of them display mosaic structures with novel domains never reported previously in a chitin synthase. In particular, the presence of a discoidin （DS） and a sterile alpha motif （SAM） domain was found in nine identified proteins. Sequence analyses and homology modelling suggest that these domains might interact with the extracellular matrix and mediate protein-protein interaction. The multi-domain putative chitin synthases from B. floridae constitute an emblematic example of the explosion of domain innovation and shuffling which predate Metazoans.

关键词： Branchiostomafloridae Chitin synthase Discoidin domain Extracellular matrix

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Holocene thermal maximum mode versus the continuous warming mode:Problems of data-model comparisons and future research prospects

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Science China Earth Sciences 2023年第8期66卷 1683-1701页

作者： Fahu CHEN Yanwu DUAN Shuo HAO Jie CHEN Xiaoping FENG Juzhi HOU Xianyong CAO Xu ZHANG Tianjun ZHOU Group of Alpine Paleoecology and Human Adaptation(alpha) Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China College of resources and Environment University of Chinese Academy of SciencesBeijing 100049China College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

The Holocene,the most recent interglacial,provides an important time window for evaluating current global warming and predicting future temperature *** the development of new temperature proxies and improvements in climate models,significant progress has been made in understanding Holocene temperature ***,a major debate persists about whether global temperatures during the Holocene followed a pattern of gradual warming from the end of the Last Glacial Maximum,which culminated in a temperature maximum in the early to middle Holocene,followed by gradual cooling in the late Holocene(the thermal maximum mode);or whether there was a continuous warming trend that continued to the present day(the continuous warming mode).Significant discrepancies exist between different proxy records as well as between proxy records and models,which have resulted in the “Holocene temperature conundrum” that has challenged paleoclimatologists for the past ***,we summarize the progress made to date in the study of Holocene temperature change via proxy reconstructions,climate model simulations,and paleoclimate data *** emphasize that the current research has limitations in terms of the multiplicity and seasonality of proxy records,the spatial heterogeneity of temperature records,and the incorporation of feedback processes(e.g.,vegetation,cloudradiation feedback) in climate *** limitations have hindered a comprehensive understanding of the processes and mechanisms of Holocene temperature *** solve the “Holocene temperature conundrum”,it is necessary to strengthen theoretical research on climate proxies from the perspective of the underlying processes and mechanisms,elucidate the seasonal response of various temperature proxies,emphasize regional differences in temperature changes,and expand quantitative temperature reconstructions to areas with limited ***,it is also necessary to improve the simulation performance of complex

关键词： Holocene temperature change Thermal maximum mode Continuous warming mode Seasonality of proxies Climate simulations

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