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Lacustrine record of 800 yr hydrological variations on the central Tibetan Plateau

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Frontiers of Earth Science 2023年第4期17卷 945-955页

作者： Hongliang zhang hucai zhang Yanbin LEI School of Resources Environment and Tourism Anyang Normal UniversityAnyang 455002China School of Ecology and Environmental Science Yunnan UniversityKunming 650500China State Key Laboratory of Tibetan Plateau Earth System Environment and ResourcesInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Zige Tangco is a meromictic saline lake located on the central Tibetan *** parallel cores(ZGTC A-1 and ZGTC A-2)were collected from the lake at a water depth of 25 m during summer *** chronology of core A-1 was reconstructed based on the Constant Initial Concentration(CIC)model of 210Pb and three accelerator mass spectrometry(AMS)ages from the chitin *** hard water effect calibration of the sediment ^(14)C age showed that the reservoir effect ranged from 1655 yr at 1950 AD to 1540 yr at 1610 *** hydrological variation in Zige Tangco during the past 800 yr was reconstructed using multi-proxies,including organic and carbonate content,stable isotopes of fine-grained carbonate minerals(<38.5μm)and grain-size distribution of the lake *** results show that there were strong fluctuations in the lake level between 1200 and 1820 AD,and at least three dry periods were recorded between 1235 and 1315 AD,1410 and 1580 AD,and 1660 and 1720 AD characterized by high carbonate content,abrupt positive shifts of stable isotopes,and high sand *** low-lake-level periods during the Little Ice Age(LIA)in Zige Tangco correspond to the lower δ^(18)O values in the Guliya ice core and the lower precipitation reconstructed from tree rings in *** demonstrated that the summer monsoon on the central Tibetan Plateau weakened during the dry and cold periods,whereas the winter monsoon *** wetter periods or higher lake levels in Zige Tangco occurred at 1580-1650 AD and 1820-1900 *** shifts in stable isotopes were related to increased lake levels between 1800 and 1820 *** results also showed that the summer monsoon precipitation on the central Tibetan Plateau was mainly controlled by solar activity during the past 800 yr.

关键词： hydrological variation Zige Tangco stable isotopes central Tibetan Plateau lacustrine sediments LIA

Detecting anthropogenic impact on forest succession from the perspective of wood exploitation on the northeast Tibetan Plateau during the late prehistoric period

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Science China Earth Sciences 2022年第11期65卷 2068-2082页

作者： Fengwen LIU Shanjia zhang hucai zhang Guanghui DONG Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environment ScienceYunnan UniversityKunming 650504China Ministry of Education Key Laboratory of Western China's Environmental System College of Earth&Environmental SciencesLanzhou UniversityLanzhou 730000China

Human activities are usually considered to have had impacts on forest degradation and/or changes of forest composition in the *** Tibetan Plateau,an environmentally sensitive area,has witnessed a high intensity of human activities since the late Neolithic,but the evidence is still incomplete concerning how human activities affected the environment,especially vegetation *** may result,in part,from the fact that research on prehistoric wood utilization by humans in the northeast Tibetan Plateau(NETP)is scarce,especially from the perspective of charcoal analysis,which is an archaeological index directly related to human *** fill this gap,we report new data here concerning charcoal analysis from 24 archaeological sites dated 5200–2300 a BP in the NETP,where this period saw remarkable environmental and social *** coupling the results with published paleoenvironment records(especially pollen),we aim to explore the utilization of wood and its spatial-temporal changes,as well as the anthropogenic impacts on past forest dynamics in the *** results suggest that the wood resources collected by humans were mainly needleleaf trees(Picea *** Pinus L.),broadleaved trees(Populus L.,Salix L.,and Betula)as well as shrubs(Hippophae *** Tamarix L.),and that these were distributed around the human habitation *** was a clear spatial difference in the woody assemblage collected by humans in the period 3600–2300 a *** was likely related to the diversity of natural environments in local areas,but there was an abnormal spatial pattern of forest composition with broadleaved trees dominant above 2500 masl caused not by climate change,but by the rapid increase of human settlement and wood collection in high altitude areas of the NETP since 3600 a BP.

关键词： Charcoal records Late prehistoric period Northeast Tibetan Plateau Climate change Anthropogenic impacts

Total nitrogen and community turnover determine phosphorus use efficiency of phytoplankton along nutrient gradients in plateau lakes

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Journal of Environmental Sciences 2023年第2期124卷 699-711页

作者： Yun zhang hucai zhang Qi Liu Lizeng Duan Qichao Zhou Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental SciencesYunnan UniversityKunming 650500China

Numerous studies support that biodiversity predict most to ecosystem functioning,but whether other factors display a more significant direct impact on ecosystem functioning than biodiversity remains to be *** investigated 398 samples of the phytoplankton phosphorus resource use efficiency(RUE_(P)=chlorophyll-a concentration/dissolved phosphate)across two seasons in nine plateau lakes in Yunnan Province,*** identified the main contributors to phytoplankton RUEP and analyzed their potential influences on RUEP at different lake trophic *** results showed that total nitrogen(TN)contributed the most to RUEP among the nine lakes,whereas community turnover(measured as community dissimilarity)explained the most to RUEP variation across the two ***,TN also influenced RUEP by affecting *** richness(SR),functional attribute diversity(FAD2),and dendrogram-based functional diversity(FDc)were positively correlated with RUEP in both seasons,while evenness was negatively correlated with RUEP at the end of the rainy *** also found that the effects of biodiversity and turnover on RUEP depended on the lake trophic *** and FAD2 were positively correlated with RUEP in all three trophic *** showed a negative correlation with RUEP at the eutrophic and oligotrophic levels,but a positive correlation at themesotrophic *** had a negative influence on RUEP at the eutrophic level,but a positive influence at the mesotrophic and oligotrophic ***,our results suggested that multiple factors and nutrient states need to be considered when the ecosystem functioning predictors and the biodiversityecosystem functioning relationships are investigated.

关键词： Community turnover Biodiversity Phytoplankton Resource use efficiency Taxonomic diversity Total nitrogen

Self-supported porous copper oxide nanosheet arrays for efficient and selective electrochemical conversion of nitrate ions to nitrogen gas

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Journal of Materials Science & Technology 2023年第6期137卷 104-111页

作者： Xue Li Xue Zhao Jiapei Lv Xiuxiu Jia Shuxing Zhou Yimin Huang Fengqin Chang hucai zhang Guangzhi Hu Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental ScienceYunnan UniversityKunming 650504China College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices Hubei University of Arts and ScienceXiangyang 441053China Department of Physics UmeåUniversityS-90187 UmeåSweden

Electrochemical techniques have shown advantages for the removal of low-concentration ***,copper oxide nanosheets were grown on self-supporting nickel foam(NF)to prepare electrodes(CuO/NF),which realized the rapid and highly selective conversion of nitrate pollutants in sewage into nontoxic and harmless N_(2).The CuO/NF afforded 100%NO_(3)^(-)removal within 100 min and 99.53%selectivity for N_(2)at-50 mA without producing a lot of by-products(NO_(2)-,NH_(4)^(+),and N_(2)H_(4)).Furthermore,81.8%of NO_(3)^(-)was removed under the given conditions after six experimental *** results suggest that the cat-alyst has excellent electrochemical *** performance of CuO/NF for the electrocatalytic removal of NO_(3)^(-)in simulated wastewater(which contained Cl^(-) and SO_(4)^(2-))was almost *** of the high efficiency,high stability,and low cost of CuO/NF,this catalyst is practical for the removal of nitrate for wastewater purification.

关键词： Electrocatalysis Nitrate reduction Copper oxide nanosheet Selective conversion Nitrogen gas

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杞麓湖表层沉积物微塑料污染特征

环境科学与技术 2024年第S1期47卷 140-149页

作者：段立曾张虎才李东林许惟栋李华玉许婧徐天宝邓春暖云南大学生态与环境学院高原湖泊生态与治理研究院云南昆明650500 云南师范大学地理学部云南昆明650500

为探究杞麓湖微塑料(MPs)的污染特征及潜在来源机制,作者采用浮选法分离出36个位点表层沉积物中的MPs,通过显微镜和扫描电镜(SEM-EDS)观察MPs的表面结构、形态特征、微观结构及附着元素等,结合沉积物总氮(TN)、总磷(TP)、有机质(OM)、... 详细信息

为探究杞麓湖微塑料(MPs)的污染特征及潜在来源机制,作者采用浮选法分离出36个位点表层沉积物中的MPs,通过显微镜和扫描电镜(SEM-EDS)观察MPs的表面结构、形态特征、微观结构及附着元素等,结合沉积物总氮(TN)、总磷(TP)、有机质(OM)、碳酸盐和粒度等理化指标,探讨了MPs的分布特征、影响因素和潜在来源机制。结果表明:杞麓湖表层沉积物中MPs的检出率高达100%,其丰度范围介于50~680个/kg之间,平均丰度157.66个/kg。物理构成特征以粒径<1 mm(65.09%),纤维状(96.85%),透明(51.01%)和蓝色(38.7%)的MPs为优势组分。在人类活动、入湖河分布及常年盛行风等因素的综合作用下,MPs丰度呈现南部、东北部湖区最高,湖心和西部湖区相对较低的空间分布格局。相关分析表明,MPs丰度和组合特征均与沉积物理化因子之间无显著相关性,流域土地利用类型、人类活动和径流输入是MPs污染状况及空间分布的主导因素。依据物理组合特征,推测其来源为日常使用塑料制品(衣物洗涤、渔具使用)和周边农用地膜的分解等。整体而言,杞麓湖面临着水体富营养化、重金属污染等传统环境问题和MPs等新型污染物质并存的多重环境压力,亟需更多的关注。

关键词：湖泊沉积物组合特征丰度及分布微塑料杞麓湖

Tri-functional lanthanum-based biochar for efficient phosphorus recovery,bacterial inhibition,and soil fertility enhancement

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Biochar 2023年第1期5卷 302-318页

作者： Xiuxiu Jia Xue Zhao Yingtang Zhou Fan Li Wen Liu Yimin Huang hucai zhang Jinxing Ma Guangzhi Hu Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental ScienceYunnan UniversityKunming 650504China College of Chemistry and Engineering Yunnan Normal UniversityKunming 650092China National Engineering Research Center for Marine Aquaculture Marine Science and Technology CollegeZhejiang Ocean UniversityZhoushan 316004China Key Laboratory of Water and Sediment Sciences Ministry of EducationCollege of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education School of EcologyEnvironment and ResourcesGuangdong University of TechnologyGuangzhou 510006China

Excess phosphorus(P)in water can lead to eutrophication and upset ecological *** this study,biochar with ultrathin two-dimensional nanosheets from the natural mesocarp of shaddock was chosen as the *** highly dispersed and small particle size of La(OH)_(3) on the surface of the nanosheets(MSBL3)was successfully achieved using chemical impregnation for the adsorption of P in aqueous solution,and the maximum adsorption capacity was 260.0 mg P g^(−1)[La].The differences in surface crystallization of La(OH)_(3) on biochar at different La loadings were analyzed using the high-precision characterization *** six adsorption-desorption cycles,MSBL3 retained 76.7%of its initial performance in terms of the P adsorption *** preparation of 1 g of MSBL3 costs about RMB 1,and it could reduce the P concentration in 2.6 ton of Laoyu River water to below the eutrophication threshold;and the inhibitory effect of MSBL3 on the eutrophication of water bodies was confirmed by the growth state of water ***,0.1 M MSBL3 could inhibit Escherichia coli and Staphylococcus aureus up to 98.7%and 85.0%,respectively,which indicates that MSBL3 can be used to recover P from water and also to improve water *** addition,the growth of the maize seedlings verified that the P-absorbed MSBL3 waste is a good soil fertilizer and can solve the problem of post-treatment of the *** conclusion,MSBL3 prepared in this study is a promising P sorbent for application.

关键词： Two-dimensional ordered biochar Lanthanum hydroxide phosphorus adsorbent Adsorption sludge re-planning Antibacterial

Molecular fossil and paleovegetation records of paleosol S4 and adjacent loess layers in the Luochuan loess section, NW China

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Science China Earth Sciences 2008年第3期51卷 321-330页

作者： zhang hucai YANG MingSheng zhang WenXiang LEI GuoLiang CHANG FengQin PU Yang FAN HongFang Key Laboratory of Western China’s Environmental Systems Ministry of EducationCollege of Earth and Environment SciencesLanzhou UniversityLanzhou 730000China State Key Laboratory of Lake and Environment Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China

Using gas chromatography-mass spectrometry (GC-MS) technique, a series of biomarkers were identi- fied, including n-alkanes, n-alkane-2-ones, isoprenoid etc. from the loess-paleosol samples collected from the S4 and adjacent L5, L4 of the Luochuan loess section, Northwestern China. Based on these data, especially n-alkanes and high-resolution magnetic susceptibility and grain size data, the pa- leoenvironment and paleovegetation history during S4 was reconstructed. The CPI (Carbon Predomi- nance Index) and correlation between n-alkanes and magnetic susceptibility and grain size data dem- onstrated that the molecular fossils in paleosol and loess layers can reflect the vegetation condition during the loess-paleosol formation, if the allochthonous organic inputs could be excluded reasonably. The ACL (average chain length) index is correlated well with paleomagnetic susceptibility and grain size variations, displaying their good synchrony with warm and humid climate. However, it relatively lagged behind the paleomagnetic susceptibility and the grain size variations when the climate began to deteriorate. During the formation period of paleosol, the n-alkanes was dominated by C31 homologue, indicating that the primary organic input originated from herbs. Our study also demonstrated that the herbs were more flourish than wood plants in Loess Plateau, especially in the Luochuan area during the warm and humid phase, and there was no typical forest vegetation developed in the studied period.

关键词： paleoenvironment Paleosol S4 Luochuan loess section biomarker paleovegetation

Climatic and environmental implications from n-alkanes in glacially eroded lake sediments in Tibetan Plateau:An example from Ximen Co

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Chinese Science Bulletin 2011年第14期56卷 1503-1510页

作者： PU Yang zhang hucai WANG YongLi LEI GuoLiang NACE Trevor zhang ShuPing School of Remote Sensing Nanjing University of Information Science & Technology Nanjing 210044 China State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008. China Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences. Lanzhou 730000 China Duke University. Divisio. of Earth and Ocean Sciences Durham. North Carolina 27708-0227. USA

Gas chromatography-mass spectrometry was used to identify a series of n-alkanes in the sediments of a typical glacially eroded lake in the eastern Tibetan *** comparing the distribution patterns of n-alkanes in lake sediments,surface soils and cow manure,it was shown that n-C 27-n-C 33 alkanes in the soil ecosystem of Ximen Co are derived from vascular plant species and that the distribution pattern of n-C 27-n-C 33 alkanes remains unchanged during the feeding and digestion processes of *** relative percentage of C 27,C 29 and C 31 n-alkanes decreased from the bottom to the top of the sediment core showing a trend of degradation of higher plants in the Ximen Co lake region during the formation of the 44 cm core.210 Pb dating,combined with pre-existing AMS 14 C dating results showed that the depositional core reflects climatic and environmental variations since about 900 years before *** n-alkane indexes (ACL 27-33,P aq,P wax) are comparable with regional temperature variation,especially recording the Little Ice Age event (LIA).This study highlights that n-alkanes are valid proxies for paleo-climate and paleo-environment reconstruction,despite the same distribution patterns in n-alkane molecular fossils derived from a typical glacially eroded lake.

关键词：湖泊沉积物青藏高原东部正构烷烃环境变化古气候侵蚀冰川合作

EVIDENCE OF NEOTECTONIC IMPACT ON A LARGE SEDIMENTARY BASIN BETWEEN TIBETAN PLATEAU AND GOBI ALTAY,NW CHINA

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第四纪研究 2009年第4期29卷 687-695页

作者： K. Hartmann B. Wtinnemann hucai zhang Department of Earth Sciences Freie Universitat Berlin Malteserstrraβe 74 - 100 12249 Berlin Germany State Key Laboratoryof Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

The Ejina( Gaxun Nur) Basin-enclosed by the Tibetan Plateau in the south and the Gobi Altay in the north hascontinuously evolved as a strong continental endorheic depositional environment. Medium scale geomorphological mappingby Landsat- and Corona-Images as well as SRTM-topographic data, combined with field-surveys and geophysicalinvestigation provides evidence for tectonic impact on sedimentary processes during the Late *** of SRTM-Data and Landsat-Images reveal a system of up to 20m high inverted channels developed on theinactive eastern part of the large Hei river drainage delta south of the ancient lake Juyanze. The complex evolution of theselandforms requires a relative lowering of the lake basin at least two times since the last 40ka. A 26m high cliff section ofgravel-covered lake sediments within the Juyanze paleolake indicates a strong subsidence of the lake bottom of 10m/1000yrssince 18kaB. *** of Ejina river oasis a distinct north-south striking scarp up to 13m high constitutes the eastern margin of theGaxun Nur. Palaeodrainage channels derived from the Gobi Altay. They display a sinistral offset of some decametres alonga set of WE-trending faults. The rhombic shape of the modern dry Gaxun Nur, fossil cliffs,well preserved beach ridges alongthe margins of the palaeolake system as well as gravel covered topsets of lacustrine sediments indicate local displacements ofmorphological features. The displacements of lake sediments at the southern margin of the modern Gaxun Nur Basin imply asubsidence of at least 0.81m/1000 yrs since 25kaB. P. as a result of a pull-apart development due to the left stepping faultsin a sinistral system.

关键词：西藏高原第四纪地质结构湖泊