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Effects of formal credit on pastoral household expense: Evidence from the Qinghai-Xizang Plateau of China
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作者 Yan Zhang Yi Huang +1 位作者 Fan Zhang Zeng Tang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1774-1785,共12页
Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'welfare.In pastoral China,formal financial institutions are gradually increasing.Howeve... Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'welfare.In pastoral China,formal financial institutions are gradually increasing.However,a limited understanding remains of how formal credit affects herders'household expenses.Based on a survey of 544 herders from the Qinghai-Xizang Plateau of China,this study adopted the propensity score matching approach to identify the effect of formal credit on herders'total household expenses,daily expenses,and productive expenses.The results found that average age,grassland mortgage,and other variables significantly affected herders'participation in formal credit.Formal credit could significantly improve household expenses,especially productive expenses.A heterogeneity analysis showed that formal credit had a greater impact on the household total expense for those at higher levels of wealth;however,it significantly affected the productive expense of herders at lower wealth levels.Moreover,the mediating effect indicated that formal credit could affect herders'household income,thus influencing their household expenses.Finally,this study suggests that policies should improve herders'accessibility to formal credit. 展开更多
关键词 formal credit herders EXPENSE qinghai-xizang plateau
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Calculation of Solar Albedo and Radiation Equilibrium over the Qinghai-Xizang Plateau and Analysisof Their Climatic Features 被引量:6
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作者 赵平 陈隆勋 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2000年第1期140-156,共17页
Using radiation data from the Automatic Weather Stations (AWSs) for thermal balance obser-vations, which were set up at Lhasa, Nagqu, Xigaze and Nyingchi by the Sino-Japanese Asian Monsoon Mechanism Co-operative Proje... Using radiation data from the Automatic Weather Stations (AWSs) for thermal balance obser-vations, which were set up at Lhasa, Nagqu, Xigaze and Nyingchi by the Sino-Japanese Asian Monsoon Mechanism Co-operative Project in 1993–1996, and 1985–1989 Earth Radiation Balance Experiment (ERBE) measurements of Langley Research Center/NASA of US, and 1961–1996 monthly mean data from 148 surface stations over the Qinghai-Xizang Plateau (QXP) and its neighborhood, study is performed on empirical calculation methods of surface albedo, surface total radiation, planetary albedo and outgoing longwave radiation with the climatic features of radiation balance at the surface and the atmospheric top examined. Evidences suggest that the empirical formulae for surface albedo, planetary albedo, surface to-tal radiation and outgoing longwave radiation from the atmospheric top are capable of describing their seasonal and interannual variations over the QXP. The surface albedo is marked by noticeable seasonal variation and yearly mean of 0.22 with the maximum of 0.29 in January and minimum of 0.17 in July and August; in winter the albedo has great horizontal difference, bigger in the moun-tains than in the river valleys, and small in summer. The planetary albedo shows a smaller range of its annual variation with the yearly mean of 0.37, the maximum (minimum) occurring in February and March (autumn). In winter its high-value regions are mainly at Gar (Shiquanhe) in the western QXP and from the southwestern Qinghai to the northeastern Tibet and the low-value area at the northern slope of the central Himalayas; in summer, however, the albedo distribution displays clear-ly a progressive decrease from southeast to northwest. As for the surface total radiation, its values and annual varying range are smaller in the east than in the southwest. Its high-value center is at the southern slope of the Himalayas in winter and makes a conspicuous westward migration in spr-ing, remaining there for a long time, and it begins to retreat eastward in autumn. Monthly mean values of the surface net radiation are all positive and larger in summer than in winter. The net ra-diation is significantly intensified under the combined effect of surface total radiation and surface albedo from spring to early summer, resulting in the strongest sector in the mid plateau with its center staying nearly motionless from March to September, and is reduced in autumn dominantly by surface effective radiation. The earth-atmosphere system loses heat outward from October to next February and gains in other months. On an average, the plateau gains heat of 15 W m-2 on an annual basis. Key words The Qinghai-Xizang Plateau - Albedo - Radiation balance - Climatic feature (1)This work was supported under the auspices of the National (G1998040800) and CAS’s Key Project for Basic Research on Tibetan Plateau (KZ951-A1-204; KZ95T-06). 展开更多
关键词 The qinghai-xizang plateau ALBEDO Radiation balance Climatic feature
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INTERNATIONAL COOPERATIVE STUDIES ON THE QINGHAI-XIZANG PLATEAU
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作者 Zheng Du(Institute of Geography, the CAS, Beijing 100101)Deputy Director of the CAS Integrated Scientifie Expedition to the Qinghai-Xizang Plateau and Director of the CAS Institule of Geopgraphy 《Bulletin of the Chinese Academy of Sciences》 1995年第2期206-208,共3页
The Qinghai-Xizang Plateau is known as "the roof of the world".Its intensive uplifting has been one of the most important events in the past two million years of the earth history,which strongly affects the ... The Qinghai-Xizang Plateau is known as "the roof of the world".Its intensive uplifting has been one of the most important events in the past two million years of the earth history,which strongly affects the physical environment and human activities both in the plateau itself and in its nearby regions.As a natural laboratory in the fields of geo-science,biology,resources and environment,the Plateau has attracted worldwide attention from the academic circles.Because the main body of the plateau is located in China,Chinese scientists shoulder major responsibilities for 展开更多
关键词 INTERNATIONAL COOPERATIVE STUDIES ON THE qinghai-xizang plateau
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VARIATION OF d δ^(18)O/dT IN PRECIPITATION IN THE QINGHAI-XIZANG PLATEAU 被引量:5
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作者 章新平 《Chinese Geographical Science》 SCIE CSCD 1997年第4期339-346,共8页
The relations between δ18O and temperature on the different time scales were analysed,according to the data from Tuotuohe (34°13’N, 96°25’E; 4533 m a. s. l. ), Delingha (37°22’N,97°22’E; 2981 ... The relations between δ18O and temperature on the different time scales were analysed,according to the data from Tuotuohe (34°13’N, 96°25’E; 4533 m a. s. l. ), Delingha (37°22’N,97°22’E; 2981 m a. s. l. ) and Xining (36°37’N, 101°46’E; 2261 m a. s. l. ) in the Qnghai-Xizang Plateau. The results show that the significance of d δ18O/dT on different time scales are different.The d δ18O/dT on the synoptic scale reflects the interdependent relation between δ18O and temperature in the short-term synoptic scale process; the d δ18O/d T on the seasonal scale reflects the relation between them whithin a year; and the d δ18O/d T on the climatic scale reflects the relation between them in the long-term climatic change. The calculated d δ18O/dT on climatic scale is very close to the theoretical values on the condition of advection transport for Tuotuohe Station. However, there are great differences between the calculated and the theoretical values for Delingha and Xining stations. 展开更多
关键词 qinghai-xizang plateau OXYGEN ISOTOPE temperature time scale
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Structural Variation of an Atmospheric Heat Source over the Qinghai-Xizang Plateau and Its Influence on Precipitation in Northwest China 被引量:8
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作者 魏娜 巩远发 何金海 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第5期1027-1041,共15页
NCEP/NCAR reanalysis data and a 47-year precipitation dataset are utilized to analyze the relationship between an atmospheric heat source (hereafter called 〈 Q1 〉) over the Qinghai-Xizang Plateau (QXP) and its s... NCEP/NCAR reanalysis data and a 47-year precipitation dataset are utilized to analyze the relationship between an atmospheric heat source (hereafter called 〈 Q1 〉) over the Qinghai-Xizang Plateau (QXP) and its surrounding area and precipitation in northwest China. Our main conclusions are as follows: (1) The horizontal distribution of 〈 Q1 〉 and its changing trend are dramatic over QXP in the summer. There are three strong centers of 〈 Q1 〉 over the south side of QXP with obvious differences in the amount of yearly precipitation and the number of heat sinks predominate in the arid and semi-arid regions of northwest China (NWC), beside the northern QXP with an obvious higher intensity in years with less precipitation. (2) In the summer, the variation of the heat source's vertical structure is obviously different between greater and lesser precipitation years in eastern northwest China (ENWC). The narrow heat sink belt forms between the northeast QXP and the southwestern part of Lake Baikal. In July and August of greater precipitation years, the heating center of the eastern QXP stays nearly over 35°N, and at 400 hPa of the eastern QXP, the strong upward motion of the heating center constructs a closed secondary vertical circulation cell over the northeast QXP (40~ 46~N), which is propitious to add precipitation over the ENWC. Otherwise, the heating center shifts to the south of 30°N and disappears in July and August of lesser precipitation years, an opposite secondary circulation cell forms over the northeast QXP, which is a disadvantage for precipitation. Meanwhile, the secondary circulation cell in years with more or less precipitation over the ENWC is also related to the heat source over the Lake Baikal. (3) The vertical structure of the heat source over the western QXP has obvious differences between greater and lesser precipitation years in western northwest China in June and July. The strong/weak heat source over the western QXP produces relatively strong/weak ascending motion and correspondingly constructs a secondary circulation cell in lesser/greater precipitation years. 展开更多
关键词 qinghai-xizang plateau atmospheric heat source/sink greater/lesser precipitation years northwest China
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Changes and spatial patterns of the differences between ground and air temperature over the Qinghai-Xizang Plateau 被引量:5
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作者 ZHANG Wengang LI Shuxun +1 位作者 WU Tonghua PANG Qiangqiang 《Journal of Geographical Sciences》 SCIE CSCD 2007年第1期20-32,共13页
The difference between ground soil and air temperature (Ts-Ta) was studied by using the data of ground and air temperature of 99 stations over the Qinghai-Xizang (Tibet) Plateau from 1960 to 2000,and its spatial d... The difference between ground soil and air temperature (Ts-Ta) was studied by using the data of ground and air temperature of 99 stations over the Qinghai-Xizang (Tibet) Plateau from 1960 to 2000,and its spatial distribution and time changing tendency have been diagnosed by principal component analysis and power spectral analysis methods. The results show that the values of (Ts-Ta) are the maximum in June and the minimum in December. The first three loading eigenvectors, which reflect the main spatially anomalous structure of (Ts-Ta) over the Qinghai-Xizang Plateau, contain the contrary changing pattern between the northwestern and the southeastern regions, the pattern response of the sea level elevation and the geography, and the pattern response of the distribution of the permafrost. There are four patterns of time evolution including the patterns of monotonous increasing or decreasing trends, the basic stability pattern and the parabola pattern with the minimum value. (Ts-Ta) has a periodic variation about 2 years. According to the spatial distribution of the third loading eigenvectors of (Ts-Ta) over the Qinghai-Xizang Plateau in cold season, the permafrost response region and the seasonal frozen ground response region are identified. 展开更多
关键词 qinghai-xizang plateau difference between ground and air temperature (Ts-Ta) principal component temperature subarea
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PROGRESS IN STUDIES ON GEOGRAPHICAL ENVIRONMENTS OF THE QINGHAI-XIZANG PLATEAU 被引量:2
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作者 郑度 李炳元 《Chinese Geographical Science》 SCIE CSCD 1999年第4期2-9,共8页
The Qinghai Xizang (Tibet) Plateau area was subjected to twice uplift and planation in the Tertiary. Intense uplifting of the plateau area has given rise to drastic changes and differentiation of physical environment ... The Qinghai Xizang (Tibet) Plateau area was subjected to twice uplift and planation in the Tertiary. Intense uplifting of the plateau area has given rise to drastic changes and differentiation of physical environment on the plateau and the surrounding area since 3.4 Ma B.P. Significant environmental changes with dry tendency in interior of the plateau had occurred during the last 150 ka B.P. By comparative study on several mountains of the plateau, two systems of the structure type of the altitudinal belt are identified and nine groups are subdivided . A distribution model with close relevance to highland uplift effect has been generalized. A number of striking geo ecological phenomena and their spatial pattern such as moisture corridor, dry valleys, high cold meadow zone, and high cold arid core area are investigated and discussed. Based on the thermal conditions, moisture regimes and variation in landforms of the plateau is sequentially demarcated. A tentative scheme of 2 temperature belts, 10 natural zones and 28 physical districts has been proposed not including southern slopes of the East Himalayas. The Qinghai Xizang Plateau is sensitive to “green house effect”, showing close relation with global change. Characteristics of temperature and precipitation on the plateau during the last 2000 years, and response of glaciers, snow deposit and permafrost on the plateau to global change are dealt with in the present paper. 展开更多
关键词 QINGHAI Xizang plateau GEOGRAPHICAL environment palaeo GEOGRAPHICAL evolution ENVIRONMENTAL DIFFERENTIATION
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Focal Depth of Earthquakes in the Qinghai-Xizang Plateau and Its Tectonic Implication
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作者 Zheng SihuaCenter for Analysis and Prediction,SSB,Beijing 100036,China 《Earthquake Research in China》 1996年第1期20-29,共10页
In the previous work of the present study,moment tensors of 11 major earthquakes in the Qinghai-Xizang Plateau and its surrounding region from 1966 to 1980 are estimated by generalized inversion technique.The seismic ... In the previous work of the present study,moment tensors of 11 major earthquakes in the Qinghai-Xizang Plateau and its surrounding region from 1966 to 1980 are estimated by generalized inversion technique.The seismic source time function and focal depth are immediately determined in the inversion.The results indicated that all earthquakes investigated here are shallow events within the upper crust.The purpose of this paper is to present a summary of the distribution of focal depths of earthquakes in and near the Qinghai-Xizang Plateau from the above result,combining the focal depths of 78 significant earthquakes from 1964 to 1986,which are relocated individually by other authors,as well as to discuss its tectonic implication. 展开更多
关键词 qinghai-xizang plateau Focal depth ROCK heat STATE ROCK THERMAL STATE THERMAL STATE of the lithosphere.
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THE FLORISTIC STRUCTURE OF THE XIZANG PART OF THE QINGHAI-XIZANG PLATEAU PLANT SUBKINGDOM
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作者 李恒 武素功 《Chinese Geographical Science》 SCIE CSCD 1991年第3期27-39,共13页
The flora of the Qinghai-Xizang Plateau belongs to the floristic subkingdom of the Holarctic plant kingdom. The Xizang part of this subkingdom can be divided into 4 plant regions. 1) the Yarlung Zangbo River valley re... The flora of the Qinghai-Xizang Plateau belongs to the floristic subkingdom of the Holarctic plant kingdom. The Xizang part of this subkingdom can be divided into 4 plant regions. 1) the Yarlung Zangbo River valley region. There are 1,003 species of seed plants, making up 19.38% of the total species in Xizang, and 159 endemic species, 15.89% of the total seed plants. The flora originates mainly from the East Himalayas and the Hengduan Mountains. 2) The Tanggute region. There are 349 species of seed plants and 10 endemic species. The flora represents an intermediate one between the Qinghai-Xizang Plateau and the Hengduan Mountains.3) The Qiangtang region. There are 255 species of seed plants and 18 endemic species. The flora derived from the Himalayan flora and mixed with a great number of Tethysian elements. 4) the Ali region. There are 547 species of seed plants and 41 endemic species. The flora seems to be closely related to Tethysian one. 展开更多
关键词 FLORISTIC STRUCTURE qinghai-xizang plateau PLANT subkingdom Xizang
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Crustal and uppermost mantle structure of the northeastern Qinghai-Xizang Plateau from joint inversion of surface wave dispersions and receiver functions with P velocity constraints
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作者 Pei Zhang Xiaodong Song +2 位作者 Jiangtao Li Xingchen Wang Xuezhen Zhang 《Earthquake Science》 2024年第2期93-106,共14页
Lithospheric structure beneath the northeastern Qinghai-Xizang Plateau is of vital significance for studying the geodynamic processes of crustal thickening and expansion of the Qinghai-Xizang Plateau. We conducted a j... Lithospheric structure beneath the northeastern Qinghai-Xizang Plateau is of vital significance for studying the geodynamic processes of crustal thickening and expansion of the Qinghai-Xizang Plateau. We conducted a joint inversion of receiver functions and surface wave dispersions with P-wave velocity constraints using data from the Chin Array Ⅱ temporary stations deployed across the Qinghai-Xizang Plateau. Prior to joint inversion, we applied the H-κ-c method(Li JT et al., 2019) to the receiver function data in order to correct for the back-azimuthal variations in the arrival times of Ps phases and crustal multiples caused by crustal anisotropy and dipping interfaces. High-resolution images of vS, crustal thickness, and vP/vSstructures in the Qinghai-Xizang Plateau were simultaneously derived from the joint inversion. The seismic images reveal that crustal thickness decreases outward from the Qinghai-Xizang Plateau. The stable interiors of the Ordos and Alxa blocks exhibited higher velocities and lower crustal vP/vSratios. While, lower velocities and higher vP/vSratios were observed beneath the Qilian Orogen and Songpan-Ganzi terrane(SPGZ), which are geologically active and mechanically weak, especially in the mid-lower crust.Delamination or thermal erosion of the lithosphere triggered by hot asthenospheric flow contributes to the observed uppermost mantle low-velocity zones(LVZs) in the SPGZ. The crustal thickness, vS, and vP/vSratios suggest that whole lithospheric shortening is a plausible mechanism for crustal thickening in the Qinghai-Xizang Plateau, supporting the idea of coupled lithospheric-scale deformation in this region. 展开更多
关键词 joint inversion receiver functions surface waves crustal thickness vP/vS ratio NE qinghai-xizang plateau
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Relationship Between Climate Change and Marmot Plague of Marmota himalayana Plague Focus—the Altun Mountains of the Qinghai-Xizang Plateau,China,2000–2022
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作者 Qun Duan Xiaojin Zheng +16 位作者 Zhiqiang Gan Dongyue Lyu Hanyu Sha Xinmin Lu Xiaoling Zhao Asaiti Bukai Ran Duan Shuai Qin Li Wang Jinxiao Xi Di Wu Peng Zhang Deming Tang Zhaokai He Huaiqi Jing Biao Kan Xin Wang 《China CDC weekly》 SCIE CSCD 2024年第4期69-74,I0006,共7页
Introduction:Plague is a zoonotic disease that occurs naturally in specific geographic areas.Climate change can influence the populations of the plague host or vector,leading to variations in the occurrence and epidem... Introduction:Plague is a zoonotic disease that occurs naturally in specific geographic areas.Climate change can influence the populations of the plague host or vector,leading to variations in the occurrence and epidemiology of plague in animals.Methods:In this study,we collected meteorological and plague epidemiological data from the Marmota himalayana plague focus in the Altun Mountains of the Qinghai-Xizang Plateau.The data spanned from 2000 to 2022.We describe the climatic factors and plague epidemic conditions and we describe their analysis by Pearson’s correlation.Results:During the period from 2000 to 2022,the isolation rates of Yersinia pestis(Y.pestis)from marmots and fleas were 9.27%(451/4,864)and 7.17%(118/1,646),respectively.Additionally,we observed a positive rate of F1 antibody of 11.25%(443/3,937)in marmots and 18.16%(142/782)in dogs.With regards to climate,there was little variation,and a decreasing trend in blowing-sand days was observed.The temperature in the previous year showed a negative correlation with the Y.pestis isolation rate in marmots(r=−0.555,P=0.011)and the positive rate of F1 antibody in marmots(r=−0.552,P=0.012)in the current year.The average annual precipitation in the previous two years showed a positive correlation with marmot density(r=0.514,P=0.024),while blowingsand days showed a negative correlation with marmot density(r=−0.701,P=0.001).Furthermore,the average annual precipitation in the previous three years showed a positive correlation with the isolation rate of Y.pestis from marmots(r=0.666,P=0.003),and blowing-sand days showed a negative correlation with marmot density(r=−0.597,P=0.009).Conclusions:The findings of this study indicate that there is a hysteresis effect of climate change on the prevalence of plague.Therefore,monitoring climate conditions can offer significant insights for implementing timely preventive and control measures to combat plague epidemics. 展开更多
关键词 PLAGUE EPIDEMIOLOGY plateau
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A new regional vegetation mapping method based on terrain-climate-remote sensing and its application on the Qinghai-Xizang Plateau
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作者 Guangsheng ZHOU Hongrui REN +4 位作者 Tong LIU Li ZHOU Yuhe JI Xingyang SONG Xiaomin LV 《Science China Earth Sciences》 SCIE EI CAS CSCD 2023年第2期237-246,共10页
Understanding the impact of climate change on vegetation and its evolution trend requires long-term accurate data on regional vegetation types and their geographical distribution.Currently,land use and land cover type... Understanding the impact of climate change on vegetation and its evolution trend requires long-term accurate data on regional vegetation types and their geographical distribution.Currently,land use and land cover types are mainly obtained based on remote sensing information.Little research has been conducted on remote sensing interpretation of vegetation types and their geographical distributions in terms of the comprehensive utilization of remote sensing,climate,and terrain.A new region vegetation mapping method based on terrain-climate-remote sensing was developed in this study,supported by the Google Earth Engine(GEE)and the random forest algorithm,which is a new generation of earth science data and analysis application platform,together with optimal vegetation mapping features obtained from the average impure reduction method and out-of-bag error value,using different information from remote sensing,climate,and terrain.This vegetation of Qinghai-Xizang Plateau with 10 m spatial resolution in 2020 was mapped,in terms of this new vegetation mapping method,Sentinel-2A/B remotely sensed images,climate,and terrain.The accuracy verification of vegetation mapping on the Qinghai-Xizang Plateau showed an overall accuracy of 89.5%and a Kappa coefficient of 0.87.The results suggest that the regional vegetation mapping method based on terrain-climate-remote sensing proposed in this study can provide technical support for obtaining long-term accurate data on vegetation types and their geographical distributions on the Qinghai-Xizang Plateau and the globe. 展开更多
关键词 Vegetation mapping Random forest algorithm GEE remote sensing qinghai-xizang plateau
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Influence of Qinghai-Xizang Plateau snow cover on interannual variability of Western North Pacific tropical cyclone tracks
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作者 Zhaohua WANG Dongliang ZHAO +1 位作者 Kejian WU Lian XIE 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第6期2060-2076,共17页
Track density function(TDF)was computed for all Western North Pacific tropical cyclones(WNP TCs)tracks from 1950 to 2018,and the TDFs were further investigated using principal component analysis(PCA)to analyze their i... Track density function(TDF)was computed for all Western North Pacific tropical cyclones(WNP TCs)tracks from 1950 to 2018,and the TDFs were further investigated using principal component analysis(PCA)to analyze their inter-annual spatial and temporal variability.Then,the relationships between each empirical orthogonal function(EOF)mode and the typhoon count,typhoon landfall count,track pattern,and the Qinghai-Xizang Plateau snow cover(QXPSC)were examined,and the possible physical mechanisms implied by the statistical relationship were explored.The results show the QXPSC significantly affected the surface-atmosphere heat exchange through snow cover(SC)level,then changed the East Asian summer monsoon regional circulation pattern,influenced the subtropical high-pressure system strength and location,and ultimately affected the WNP TCs track patterns and thus changed their landfall locations. 展开更多
关键词 tropical cyclone qinghai-xizang plateau snow cover track pattern landfall location
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Poisonous Plants of the Karakalpak Part of the Ustyurt Plateau (Uzbekistan)
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作者 Aymuratov Rapat Abduraimov Ozodbek +2 位作者 Shomurodov Habibullo Abduraimov Azizbek Adilov Bekzod 《American Journal of Plant Sciences》 CAS 2024年第2期83-94,共12页
The article presents the composition and current state of poisonous plants distributed on the Ustyurt plateau. Ustyurt is one of the largest deserts in Central Asia, differing from other deserts of the world in geogra... The article presents the composition and current state of poisonous plants distributed on the Ustyurt plateau. Ustyurt is one of the largest deserts in Central Asia, differing from other deserts of the world in geographical location, relief, flora and fauna and other features. The territory of Ustyurt occupies 21.3 million hectares, of which the Karakalpak part accounts for 7.2 million hectares. Poisonous alkaloid-bearing plants of the Karakalpak part of the Ustyurt plateau Anabasis aphylla, Atriplex flabellum, Kalidium capsicum, Salsola arbusculaeformis, Salsola foliosa, Aellenia subaphylla, Anabasis brachiata, Rheum tataricum, Capparis spinosa, Glycyrrhiza aspera. Alkaloid-bearing plants that are not eaten or poorly eaten by cattle Ephedra distachya, Delphinium songaricum, Anabasis salsa, alkaloid-bearing plants eaten by animals without harm Carex physodes, Eremopyrum orientale, Agrophyllum repens, Astragalus amodendron, Astragalus villosissimus, species of the genera Calligonum, Salsola. Poisonous plants of the Karakalpak part of the Ustyurt plateau. An analysis of the pasture flora of the Karakalpak part of the Ustyurt plateau shows that 62 species of wild poisonous plants belonging to 49 genera and 19 families grow here. Although these plants are considered poisonous, but in modern pharmaceutics and medicine, they are used as medicinal. 展开更多
关键词 Ustyurt plateau SPECIES Poisonous DESERT Climate Change
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Mechanism of Diabatic Heating on Precipitation and the Track of a Tibetan Plateau Vortex over the Eastern Slope of the Tibetan Plateau
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作者 Yuanchang DONG Guoping LI +3 位作者 Xiaolin XIE Long YANG Peiwen ZHANG Bo ZENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期155-172,共18页
Existing studies contend that latent heating(LH)will replace sensible heating(SH)to become the dominant factor affecting the development of the Tibetan Plateau vortex(TPV)after it moves off the Tibetan Plateau(TP).How... Existing studies contend that latent heating(LH)will replace sensible heating(SH)to become the dominant factor affecting the development of the Tibetan Plateau vortex(TPV)after it moves off the Tibetan Plateau(TP).However,in the process of the TPV moving off the TP requires that the airmass traverse the eastern slope of the Tibetan Plateau(ESTP)where the topography and diabatic heating(DH)conditions rapidly change.How LH gradually replaces SH to become the dominant factor in the development of the TPV over the ESTP is still not very clear.In this paper,an analysis of a typical case of a TPV with a long life history over the ESTP is performed by using multi-sourced meteorological data and model simulations.The results show that SH from the TP surface can change the TPV-associated precipitation distribution by temperature advection after the TPV moves off the TP.The LH can then directly promote the development of the TPV and has a certain guiding effect on the track of the TPV.The SH can control the active area of LH by changing the falling area of the TPV-associated precipitation,so it still plays a key role in the development and tracking of the TPV even though it has moved out of the main body of the TP. 展开更多
关键词 eastern slope of the Tibetan plateau diabatic heating Tibetan plateau vortex precipitation distribution TRACK
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Palaeogene Sandstones of the Manika Plateau in Kolwezi (DR Congo): Sedimentological and Geochemical Characterization, Provenance, Palaeoalteration and Tectonic Context
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作者 Pierre T. Mashala Faidance Mashauri +1 位作者 Samy M. Malango Christian K. Mulopwe 《Open Journal of Geology》 CAS 2024年第7期705-722,共18页
This work presents a study of the Paleogene sandstones of the Manika plateau in Kolwezi, DR Congo. These sandstones belong to the “Grès polymorphes” group, which together with the overlying “Sables ocre” make... This work presents a study of the Paleogene sandstones of the Manika plateau in Kolwezi, DR Congo. These sandstones belong to the “Grès polymorphes” group, which together with the overlying “Sables ocre” makes up the Kalahari Supergroup. Sedimentological and geochemical analyses have enabled us to characterize these sandstones and determine their origin, the conditions of their formation and the tectonic context in which they were developed. The results show that the sandstones are quartz arenites with a high level of mineralogical, textural and chemical maturity. They are recycled sandstones, formed in an intracratonic sedimentary basin, in the context of a passive continental margin, after a long fluvial transport of sediments. These sandstones initially come from intense alteration of magmatic rocks with felsic composition, mainly tonalite-trondhjemite-granodiorite (TTG) complexes, in hot, humid palaeoclimatic conditions and oxidizing environments. 展开更多
关键词 Sandstone SEDIMENTOLOGY Geochemistry Palaeoalteration Tectonic Context Manika plateau DR Congo
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Changes in Spring Snow Cover over the Eastern and Western Tibetan Plateau and Their Associated Mechanism
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作者 Fangchi LIU Xiaojing JIA Wei DONG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期959-973,共15页
The spring snow cover(SC)over the western Tibetan Plateau(TP)(TPSC)(W_TPSC)and eastern TPSC(E_TPSC)have displayed remarkable decreasing and increasing trends,respectively,during 1985–2020.The current work investigate... The spring snow cover(SC)over the western Tibetan Plateau(TP)(TPSC)(W_TPSC)and eastern TPSC(E_TPSC)have displayed remarkable decreasing and increasing trends,respectively,during 1985–2020.The current work investigates the possible mechanisms accounting for these distinct TPSC changes.Our results indicate that the decrease in W_TPSC is primarily attributed to rising temperatures,while the increase in E_TPSC is closely linked to enhanced precipitation.Local circulation analysis shows that the essential system responsible for the TPSC changes is a significant anticyclonic system centered over the northwestern TP.The anomalous descending motion and adiabatic heating linked to this anticyclone leads to warmer temperatures and consequent snowmelt over the western TP.Conversely,anomalous easterly winds along the southern flank of this anticyclone serve to transport additional moisture from the North Pacific,leading to an increase in snowfall over the eastern TP.Further analysis reveals that the anomalous anticyclone is associated with an atmospheric wave pattern that originates from upstream regions.Springtime warming of the subtropical North Atlantic(NA)sea surface temperature(SST)induces an atmospheric pattern resembling a wave train that travels eastward across the Eurasian continent before reaching the TP.Furthermore,the decline in winter sea ice(SIC)over the Barents Sea exerts a persistent warming influence on the atmosphere,inducing an anomalous atmospheric circulation that propagates southeastward and strengthens the northwest TP anticyclone in spring.Additionally,an enhancement of subtropical stationary waves has resulted in significant increases in easterly moisture fluxes over the coastal areas of East Asia,which further promotes more snowfall over eastern TP. 展开更多
关键词 snow cover Tibetan plateau long-term changes SPRING
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Occurrence of microplastics in natural and farmland soil in the Qilian Mountains of the Northern Tibetan Plateau
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作者 KANG Qiangqiang ZHANG Yulan +5 位作者 KANG Shichang ZHANG Shengyin LUO Xi LI Longrui WANG Zhaoqing ZHANG Shuncun 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2159-2172,共14页
Microplastics(MPs)become ubiquitous in soil and are an environmental and public health concern worldwide.However,the status of MPs in natural and farmland soils in remote areas remains poorly understood.In this study,... Microplastics(MPs)become ubiquitous in soil and are an environmental and public health concern worldwide.However,the status of MPs in natural and farmland soils in remote areas remains poorly understood.In this study,we investigated the characteristics of MPs in natural and farmland soils along two transects in the Qilian Mountains of the northern Tibetan Plateau.The average abundance of MPs in natural and farmland soils was 29,778 and 56,123 items kg^(-1),respectively,with a detection size range of 10-1000μm.MPs in the size range of 10-100μm accounted for 84.1%of particles detected.Among the 21 polymers detected,polyethylene dominated in both farmland and natural soils.The shape of MPs was dominated by fragments(95.8%),followed by fibers(3.8%)and beads(0.4%).The abundance of MPs was positively correlated with increasing altitude in natural soils.There was no significant correlation between the abundance of MPs and soil physicochemical properties due to the narrow range of values of soil physicochemical properties.With the growing concern regarding MPs pollution,research on the status of MPs in high altitude and remote areas is critical to understanding their global cycle. 展开更多
关键词 Microplastics pollution SOIL Remote areas Tibetan plateau
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Assessment of natural and anthropogenic impacts on terrestrial water storage in the Loess Plateau based on different types of GRACE/GRACE-FO solutions
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作者 ZHANG Cheng CHEN Peng +4 位作者 ZHU Chengchang LU Jierui ZHANG Yuchen YANG Xinyue WU Mengyan 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2173-2192,共20页
Changes in water resource storage are inevitable due to climate change and human activities,thus understanding alterations in water storage within a specific region is imperative for the planning and management of wat... Changes in water resource storage are inevitable due to climate change and human activities,thus understanding alterations in water storage within a specific region is imperative for the planning and management of water resources.Data from the Gravity Recovery and Climate Experiment(GRACE)satellite mission are extensively employed to analyze large-scale total terrestrial water storage anomalies(TWSA).In this study,we derived a more reliable TWSA using different types of GRACE gravity models,which served as the basis for evaluating spatial and temporal variations in total terrestrial water storage and its hydrological components(soil moisture and groundwater)across the Loess Plateau.Additionally,we analyzed the impact of natural and anthropogenic influences on water storage in the Loess Plateau,categorizing them into primary and secondary influences,utilizing data on climate and human activities.The findings revealed a declining trend in the overall TWSA of the Loess Plateau,with a rate of decrease at-0.65±0.05 cm/yr from 2003 to 2020(P<0.01).As the direct factors affecting TWSA,soil moisture dominated the change of TWSA before 2009,and groundwater dominated the change of TWSA after 2009.Spatially,there was variability in the changes of TWSA in the Loess Plateau.More in-depth studies showed that soil moisture changes in the study area were primarily driven by evapotranspiration and temperature,with precipitation and vegetation cover status playing a secondary role.Human activities had a secondary effect on soil moisture in some sub-regions.Population change and agricultural development were major factors in altering groundwater storage in the study area.Other than that,groundwater was influenced by natural factors to a limited extent.These findings provided valuable insights for local governments to implement proactive water management policies. 展开更多
关键词 GRACE Terrestrial water storage Human activity Loess plateau
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Significant lake expansion has accelerated permafrost degradation on the Qinghai-Tibet Plateau
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作者 LI Qingpeng LIU Wenhui +6 位作者 LIU Hairui ZHOU Guanghao SONG Xianteng LI Qing LUO Bingnan SONG Bangxu ZHANG Qi 《Journal of Mountain Science》 SCIE CSCD 2024年第1期68-83,共16页
In recent years, lakes on the Qinghai-Tibet Plateau have become more responsive to climate change. In September 2011, Zonag Lake in Hoh Xil experienced sudden drainage, the water eventually flowed into Yanhu Lake, whi... In recent years, lakes on the Qinghai-Tibet Plateau have become more responsive to climate change. In September 2011, Zonag Lake in Hoh Xil experienced sudden drainage, the water eventually flowed into Yanhu Lake, which caused Yanhu Lake to continue to expand. The potential collapse of Yanhu Lake could directly threaten the operational safety of the adjacent Qinghai-Tibet Highway, Qinghai-Tibet Railway. To explore the implications of expanding lakes on the surrounding permafrost, we selected Hoh Xil Yanhu Lake on the Qinghai-Tibet Plateau to study the effect of lake expansion on permafrost degradation. The permafrost degradation in the Yanhu Lake basin from October 2017 to December 2022 was inverted using Sentinel-1 satellite image data and small baseline subset interferometry synthetic aperture radar(SBAS-In SAR) technology. Additionally, permafrost degradation from February 2007 and February 2010 was analyzed using advanced land observing satellite phased array-type L-band synthetic aperture radar(ALOS PALSAR) satellite images and differential interferometric synthetic aperture radar(D-In SAR) technique. The results showed that the permafrost around Yanhu Lake experienced accelerated degradation. Prior to the expansion of Yanhu Lake, the average annual deformation rate along the line of sight(LOS) direction was 6.7 mm/yr. After the expansion, the rate increased to 20.9 mm/yr. The integration of spatial-temporal distribution maps of surface subsidence, Wudaoliang borehole geothermal data, meteorological data, Yanhu Lake surface area changes, and water level changes supports the assertion that the intensified permafrost degradation could be attributed to lake expansion rather than the rising air temperature. Furthermore, permafrost degradation around Yanhu Lake could impact vital infrastructure such as the adjacent Qinghai-Tibet Highway and Qinghai-Tibet Railway. 展开更多
关键词 Lake expansion SBAS-InSAR D-INSAR Permafrost deformation Qinghai-Tibet plateau
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