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science china Earth sciences 2024年第6期67卷 1932-1951页

作者： Yu LI Zhansen ZHANG Xueru ZHOU Minjun GAO Junjie DUAN Yaxin XUE Hao sHANG shiyu LIU key laboratory of western china’s environmental systems(ministry of education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China

The northern Tibetan Plateau is a climatically sensitive zone influenced by monsoon and westerly *** summer,water vapor transport can reach Qinghai Lake and the eastern section of the Qilian Mountains;in winter,westerly winds mainly control the *** article compares the wet/dry changes in the region during the mid-Holocene(MH)warm period,the medieval climate anomaly(MCA),the current warm period(CWP),and the future warm period from the perspective of *** found that the MH warm period was mainly affected by the orbit-controlled East Asian summer monsoon,and the region showed warm and humid climate *** MCA was mainly controlled by solar radiation,and there was a warm and dry *** CWP and the future warm period are mainly controlled by the rise in temperature caused by the increase in greenhouse gases,and the climate is becoming more *** wet/dry patterns in the CWP and the future warm period in the next century on the northern Tibetan Plateau are similar to those in the *** warming will lead to the expansion of the westerly belt and a gradually humid *** future wet/dry changes will be more similar to the MH warm period.

关键词： Northern Tibetan Plateau Wet/dry change Warm period similarity Driving mechanism Future assessment

Global precipitation change during the Holocene:a combination of records and simulations

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Frontiers of Earth science 2024年第1期18卷 112-126页

作者： Wangting YE Yu LI key laboratory of western china᾽s environmental systems(ministry of education) College of Earth and Environmental SciencesCenter for Hydrologic Cycle and Water Resources in Arid RegionLanzhou UniversityLanzhou 730000China

Precipitation can shape our climate both in the present and the *** though we have made significant advances in studying the mechanisms of millennial-scale climate changes through high-resolution records,we still cannot quantitatively characterize the global spatiotemporal precipitation variations within the ***,we developed a new approach to integrating data from 349 globally distributed records and climate models to reconstruct regional and global precipitation patterns over the last 12000 *** results reveal that precipitation reconstructions can be divided into monsoon-driven and westerly driven *** results suggest that an arid climate was experienced in the late glacial and early Holocene epoch(~12−7.4 cal ka BP),attaining a middle Holocene optimum(~7.4−3.5 cal ka BP),and drier after the middle *** to our reconstructions,the global precipitation reconstruction increased from the early Holocene until 3.8 cal ka BP and then subsequently *** addition,our reconstructions better reproduce the low-frequency events and extreme precipitation at the millennial scale in the hemispheres,but the performance of the reconstructions in the equatorial Pacific and the southern Hemisphere of Africa and the Americas is *** resolution of the record and the simulation capability of the climate model remain important means to improve our understanding of past climate change.

关键词： Holocene equatorial glacial

Multiscale spatiotemporal meteorological drought prediction:A deep learning approach

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Advances in Climate Change Research 2024年第2期15卷 211-221页

作者： Jia-Li ZHANG Xiao-Meng HUANG Yu-Ze sUN Department of Earth system science Ministry of Education Key Laboratory for Earth System ModellingInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China

Reliable monitoring and thorough spatiotemporal prediction of meteorological drought are crucial for early warning and decision-making regarding drought-related *** utilisation of multiscale methods is effective for a comprehensive evaluation of drought occurrence and progression,given the complex nature of meteorological ***,the nonlinear spatiotemporal features of meteorological droughts,influenced by various climatological,physical and environmental factors,pose significant challenges to integrated prediction that considers multiple indicators and time *** address these constraints,we introduce an innovative deep learning framework based on the shifted window transformer,designed for executing spatiotemporal prediction of meteorological drought across multiple *** formulate four prediction indicators using the standardized precipitation index and the standard precipitation evaporation index as core methods for drought definition using the ERA5 reanalysis *** indicators span time scales of approximately 30 d and one ***-term indicators capture more anomalous variations,whereas long-term indicators attain comparatively higher accuracy in predicting future *** focus on the East Asian region,notable for its diverse climate conditions and intricate terrains,to validate the model's efficacy in addressing the complexities of nonlinear spatiotemporal *** model's performance is evaluated from diverse spatiotemporal viewpoints,and practical application values are analysed by representative drought *** results substantiate the effectiveness of our proposed model in providing accurate multiscale predictions and capturing the spatiotemporal evolution characteristics of *** of the four drought indicators accurately delineates specific facets of the meteorological drought ***,three representative drought events,namely flash drought,sustained drought and severe drought,

关键词： Meteorological drought spatiotemporal prediction Multiscale swim transformer Deep learning

Climatic implications in earlywood and latewood width indices of Chinese pine in north central china

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Journal of Forestry Research 2024年第3期35卷 143-153页

作者： Kaixuan Yang Junzhou Zhang Haowen Fan Yuan Yan College of Geographic sciences Qinghai Normal UniversityXining 810016People's Republic of China key laboratory of Tibetan Plateau Land surface Processes and Ecological Conservation(ministry of education) Xining 810016People's Republic of China key laboratory of western china's environmental systems(ministry of education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730030People's Republic of China Gansu Liancheng Forest Ecosystem Field Observation and Research station Lanzhou UniversityLanzhou 730333People's Republic of China school of Geography and Information Engineering University of GeoscienceWuhan 430074People's Republic of China

Latewood width(LWW)indices of trees are considered a reliable proxy of summer precipitation in the Northern ***,the strong coupling and high correlation between earlywood width(EWW)and LWW indices often prevent registration of climate signals of the LWW *** this study,328-year-long earlywood width and latewood width chronologies were developed from Chinese pine at two sites in the Hasi Mountains,north central *** climate responses of these chronologies were analyzed and the LWW index used to derive sum-mer precipitation *** analyses showed that LWW was particularly influenced by earlywood growth and recorded stronger climate signals of the previous year as EWW,rather than those of the current year with infrequent summer climate ***,after removing the effect of earlywood growth using a simple regression model,the adjusted LWW chronology(LWW_(adj))showed a strong relationship with July precipitation in dry *** suggests that the LWW_(adj) chronology has the potential to be used to investigate long-term variability in summer precipitation in drought-limited regions.

关键词： Dendroclimatology Latewood width Climate response summer precipitation Earlywood effect

The δ^(15)N values of foxtail millet(setaria italica)and common millet(Panicum miliaceum)are reliable indicators of manuring practices

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science china Earth sciences 2024年第9期67卷 2910-2923页

作者： Jishuai YANG Xiaoyan YANG Ting YOU Fahu CHEN key scientific Research Base of Bioarchaeology in Cold and Arid Regions(National Cultural Heritage Administration) Key Laboratory of Western China’s Environmental Systems(Ministry of Education)College of Earth and Environmental SciencesLanzhou 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 state key laboratory of Herbage Improvement and Grassland Agro-ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730000China

Millet agriculture,which originated in northern china,alongside rice agriculture,have nurtured the Chinese *** manuring practices likely promoted and maintained sustainable millet agricultural production in the loess area of northern ***,ongoing controversy exists regarding the indicators of prehistoric manuring intensity of foxtail millet(setaria italica)and common millet(Panicum miliaceum).Here,we present the results of pot and field fertilization experiments on two millet *** findings suggest that manuring can significantly increase the δ^(15)N values of foxtail millet,and its δ^(15)N values increase with increasing manuring *** δ^(15)N values of foxtail millet leaves are systematically greater than those of grains by approximately 1.6‰.Manuring could have a long-term residual impact on increasing the δ^(15)N values of soil and millet *** with previous crop fertilization experiment results,we propose that the impact of manuring on the δ^(15)N values of non-nitrogen-fixing crops is roughly *** δ^(15)N value and amount of manure are key factors determining the extent of change in plant δ^(15)N *** millet grain δ^(15)N values can serve as reliable indicators of manuring ***,we provide an interpretive framework for assessing the correlation between manuring levels and the δ^(15)N values of archaeological millet *** δ^(15)N values of ancient millet grains suggest widespread and intensive manuring practices in prehistoric millet agriculture in northern china,spanning from the early Yangshao period to the Longshan period.

关键词： Millet farming Manuring experiment Farming system Archaeobotany North china

Applicability of different indices for delineating the boundary of arid region: A case study in northwestern china

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Journal of Earth science 2024年

作者： Xue Peng Xiang Li Yingyibing shen Xuehua Che shipei Dong Zhuolun Li key laboratory of western china's environmental systems (ministry of education)， College of Earth and environmental sciences， Center for Glacier and Desert Research， Lanzhou University

Arid regions are vital components of Earth's land surface. Clarifying the area/boundary of arid region is crucial for comprehending area changes and potential mechanisms. However， the accuracy and applicability of arid region boundary delineated by different indices remain unclear. In this study， the annual precipitation （AP）， humidity index （H）， and aridity index （K） were calculated for delineating arid region of china using 106 meteorological stations during 1990–2019. The results suggest that AP and H can accurately delineate arid region， because they are consistent with the distribution of typical soil and vegetation in arid region， whereas K is not. Moreover， AP is the best index for delineating arid region in regions with limited meteorological data， especially in studying long-term patterns and mechanisms of area changes. The accuracy of delineating arid region using H is enhanced in regions with abundant meteorological data. Over the past 30 years， influenced by the increase of atmospheric moisture influx and precipitation， the area in arid region of northwestern china decreased by 70×103–90×103km2， resulting in the present area of approximately 1.55×106km2. This study provides appropriate indices for delineating arid region， contributing to improving our knowledge of regional responses difference to climate change.

关键词：

Erratum to:Holocene temperature variation recorded by branched glycerol dialkyl glycerol tetraethers in a loess-paleosol sequence from the north-eastern Tibetan Plateau

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Frontiers of Earth science 2024年第2期18卷 460-461页

作者： Tianxiao WANG Duo WU Tao WANG Lin CHEN shilong GUO Youmo LI Chenbin ZHANG key laboratory of western china’s environmental systems(ministry of education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China Alpine Paleoecology and Human Adaptation Group(ALPHA) Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Erratum to:*** *** 10.1007/s11707-023-1094-6 The original version of this article unfortunately contained a *** presentation of was *** corrected figure is given below.

关键词： alkyl corrected Plateau

Effect of drying cracks on swelling and self-healing of bentonite-sand blocks used as engineered barriers for radioactive waste disposal

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1776-1787页

作者： Yu Tan Guangping Zhou Huyuan Zhang Xiaoya Li Ping Liu school of Civil Engineering and Mechanics Lanzhou UniversityLanzhou730000China key laboratory of Mechanics on Disaster and Environment in western china (Lanzhou University) Ministry of EducationLanzhou730000China Civil and environmental Engineering University of Wisconsin-MadisonWI53706USA

Experiments were conducted to evaluate the healing of drying cracks in air-dried bentonite-sand blocks after hydration and swelling in groundwater,providing justifications to simplify the protection of blocks prior to installation in a high-level radioactive waste *** groundwater was prepared to represent the geochemistry of Beishan groundwater,and was used to hydrate the blocks during the swelling pressure and swelling strain measurements,as Beishan is the most promising site for china's *** of the surface cracks was recorded by photography,and healing of the internal cracks was visualized by CT images and hydraulic conductivity of air-dried *** results indicate that the maximum swelling pressure and swelling strain are primarily affected by the geochemistry of Beishan groundwater,but not affected by the drying *** maximum swelling pressure and swelling strain of air-dried blocks are comparable to or even higher than the pressure and strain of fresh *** maximum swelling pressure measured in strong(*** ion strength)Beishan groundwater was 44%of the pressure measured in deionized(DI)water,and the maximum swelling strain was reduced to 23%of the strain measured in DI ***,the remained swelling of the blocks hydrated in strong Beishan groundwater was sufficient to heal the surface and internal drying cracks,as demonstrated by the pictures of surface cracks and CT *** hydraulic conductivity of the air-dried block permeated with strong groundwater was comparable(3.7×higher)to the hydraulic conductivity of the fresh block,indicating the self-healing of drying cracks after hydration and swelling in groundwater.A simplified method of protecting the block with plastic wraps before installation is recommended,since the remained swelling of the block hydrated in Beishan groundwater is sufficient to heal the drying cracks.

关键词： Beishan groundwater chemistry Bentonite buffer Drying cracks High-level radioactive waste(HLW) self-healing swelling

A near-infrared fluorescent probe for visualizing transformation pathway of Cys/Hcy and H2s and its applications in living system

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Chinese Chemical Letters 2024年第5期35卷 296-301页

作者： Yudi Cheng Xiao Wang Jiao Chen Zihan Zhang Jiadong Ou Mengyao she Fulin Chen Jianli Li key laboratory of synthetic and Natural Functional Molecule of the ministry of education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry&Materials ScienceNorthwest UniversityXi’an 710127China key laboratory of Resource Biology and Biotechnology in western china Ministry of EducationBiomedicine Key Laboratory of Shaanxi ProvinceLab of Tissue Engineeringthe College of Life SciencesFaculty of Life Science&MedicineNorthwest UniversityXi’an 710069China

sulfydryl-contained(-sH)substances including hydrogen sulfide(H_(2)s),cysteine(Cys),homocysteine(Hcy)and glutathione(GsH)play crucial roles in living systems,and their variations are closely associated with various ***,we developed a near-infrared intramolecular charge transfer(ICT)based fluorescent probe Y-NBD,achieving detection of Cys/Hcy and H_(2)s with different fluorescent signals(green-red for Cys/Hcy,red for H_(2)s),large stokes shifts(∼100/105nm or 191 nm)and high signal-background-ratio,but not responding to GsH.Y-NBD was successfully applied to image exogenous/endogenous Cys/Hcy and H_(2)s in various living cancer cells(HeLa,A549,and HepG2)and in *** not only visualized the transformation pathway of several thiols in HepG2 cells but also verified that the intestine is the main site for the activation and metabolism of Y-NBD in zebrafish,as well as realized to evaluate the degree of drug-induced liver *** work provides a promising tool for imaging Cys/Hcy and H_(2)s in living systems and shows great potency in evaluating drug-induced liver injury and its treatment.

关键词： Fluorescent probe Near-infrared Hydrogen sulfide Cysteine/homocysteine Large stokes shift Dicyanoisophorone Drug-induced liver injury

Effects of Ocean Acidification on Nitrogen Metabolism of skeletonema costatum

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Journal of Ocean University of china 2024年第5期23卷 1359-1370页

作者： WANG shuxing MI Tiezhu ZHEN Yu ZHU Jianbin key laboratory of Marine Environment and Ecology Ministry of Education College of Environmental Science and Engineering Ocean University of China laboratory for Marine Ecology and environmental science Qingdao Marine Science and Technology Center Frontiers science Center for Deep Ocean Multispheres and Earth system Ocean University of China

Ocean acidification（OA）, caused by the rising concentration of atmospheric CO2, leads to changes in the marine carbonate system. This, in turn, affects the physiological processes of phytoplankton. In response to increased p CO2levels, marine microalgae modulate their physiological responses to meet their energy and metabolic requirements. Nitrogen metabolism is a critical metabolic pathway, directly affecting the growth and reproductive capacity of marine microorganisms. Understanding the molecular mechanisms that regulate nitrogen metabolism in microalgae under OA conditions is therefore crucial. This study aimed to investigate how OA affects the expression profiles of key genes in the nitrogen metabolic pathway of the marine diatom skeletonema costatum. Our findings indicate that OA upregulates key genes involved in the nitrogen metabolic pathway, specifically those related to nitrate assimilation and glutamate metabolism. Moreover, p CO2has been identified as the predominant factor affecting the expression of these genes, with a more significant impact than pH variations in s. costatum. This research not only advances our understanding of the adaptive mechanisms of s. costatum in response to OA but also provides essential data for predicting the ecological consequences of OA on marine diatoms.

关键词： gene expression nitrogen metabolism ocean acidification skeletonema costatum transcriptome