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Climate-Vegetation Coverage Interactions in the Hengduan Mountains Area, Southeastern Tibetan Plateau, and Their Downstream Effects

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Advances in Atmospheric Sciences 2024年第4期41卷 701-716页

作者： Congxi FANG jinlei chen Chaojun OUYANG Lu WANG Changfeng SUN Quan ZHANG Jun WEN Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610299China State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an 710049China The State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China College of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China

Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in the world.This study,using multisource datasets(including satellite data and meteorological observations and reanalysis data)revealed the mutual feedback mechanisms between changes in climate(temperature and precipitation)and vegetation coverage in recent decades in the Hengduan Mountains Area(HMA)of the southeastern TP and their influences on climate in the downstream region,the Sichuan Basin(SCB).There is mutual facilitation between rising air temperature and increasing vegetation coverage in the HMA,which is most significant during winter,and then during spring,but insignificant during summer and autumn.Rising temperature significantly enhances local vegetation coverage,and vegetation greening in turn heats the atmosphere via enhancing net heat flux from the surface to the atmosphere.The atmospheric heating anomaly over the HMA thickens the atmospheric column and increases upper air pressure.The high pressure anomaly disperses downstream via the westerly flow,expands across the SCB,and eventually increases the SCB temperature.This effect lasts from winter to the following spring,which may cause the maximum increasing trend of the SCB temperature and vegetation coverage in spring.These results are helpful for estimating future trends in climate and eco-environmental variations in the HMA and SCB under warming scenarios,as well as seasonal forecasting based on the connection between the HMA eco-environment and SCB climate.

关键词： Hengduan Mountains Area normalized difference vegetation index climate change net heat flux downstream effects

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The Characteristics and Controlling Factors of Water and Heat Exchanges over the Alpine Wetland in the East of the Qinghai–Tibet Plateau

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Advances in Atmospheric Sciences 2023年第2期40卷 201-210页

作者： jinlei chen Yuan YUAN Xianyu YANG Zuoliang WANG Shichang KANG Jun WEN State Key Laboratory of Cryosphere Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Plateau Atmosphere and Environment Key Laboratory of Sichuan Province Chengdu University of Information TechnologyChengdu 610225China Key Laboratory of Land Surface Processes and Climate Change Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Atmospheric Science Lanzhou UniversityLanzhou 730000China

Alpine wetland is one of the typical underlying surfaces on the Qinghai–Tibet Plateau.It plays a crucial role in runoff regulation.Investigations on the mechanisms of water and heat exchanges are necessary to understand the land surface processes over the alpine wetland.This study explores the characteristics of hydro-meteorological factors with in situ observations and uses the Community Land Model 5 to identify the main factors controlling water and heat exchanges.Latent heat flux and thermal roughness length were found to be greater in the warm season(June–August)than in the cold season(December–February),with a frozen depth of 20–40 cm over the alpine wetland.The transfers of heat fluxes were mainly controlled by longwave radiation and air temperature and affected by root distribution.Air pressure and stomatal conductance were also important to latent heat flux,and soil solid water content was important to sensible heat flux.Soil temperature was dominated by longwave radiation and air temperature,with crucial surface parameters of initial soil liquid water content and total water content.The atmospheric control factors transitioned to precipitation and air temperature for soil moisture,especially at the shallow layer(5 cm).Meanwhile,the more influential surface parameters were root distribution and stomatal conductance in the warm season and initial soil liquid water content and total water content in the cold season.This work contributes to the research on the land surface processes over the alpine wetland and is helpful to wetland protection.

关键词： alpine wetland Qinghai-Tibet Plateau land surface processes atmospheric factor surface parameter

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Photochemical graft of γ-cyclodextrin's interior leading to in-situ charge-transfer complexes with unusual regioselectivity and its application in 3D photo-printing

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Science China Chemistry 2022年第6期65卷 1149-1156页

作者： Dongjing Zhang Wenting Liang Jigao Yi jinlei chen Yongjun Lv Ting Zhao Chao Xiao Xiangyu Xie Wanhua Wu cheng Yang Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistryState Key Laboratory of BiotherapySichuan UniversityChengdu610064China Institute of Environmental Science Department of ChemistryShanxi UniversityTaiyuan030006China Key Laboratory of Environmental Materials&Remediation Technologies of Chongqing College of Chemistry&Environmental EngineeringChongqing University of Arts and SciencesChongqing402160China College of Chemical Engineering Sichuan University of Science&EngineeringZigong643000China

Photoirradiation of anthraquinone(AQ)derivatives withγ-cyclodextrin(γ-CD)in aqueous solution led to aγ-CD derivative with a 9,10-dihydroxylanthracene grafting unprecedentedly at the 5′-position of one glucoside ofγ-CD in high efficiency.Meanwhile,another AQ enters into the remaining space of the 9,10-dihydroxylanthracene-occupiedγ-CD cavity to in-situ form a selfincluded quinhydrone charge transfer(CT)complex.The structure of the supramolecular CT complex was unambiguously demonstrated by 1 D and 2 D NMR(^(1)H NMR,^(13)C NMR,DEPT,^(1)H-^(1)H COSY,HSQC,HMBC,TOCSY,and ROESY)spectroscopies,which revealed a highly stereoselective stacking of the quinhydrone pairs in theγ-CD cavity.The supramolecular CT complex showed an unusually high binding affinity and improved oxidation resistance.Polyacrylamides bearingγ-CD or anthraquinone were respectively synthesized by co-polymerization of acrylamide with the corresponding monomer.Photoirradiation of aqueous mixtures containing these two types of polymers led to gelation,which was applied to 3 D photo-printing of soft materials.

关键词： supramolecular photochemistry cyclodextrin charge-transfer complex anthraquinone photo-printing

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Cryosphere as a temporal sink and source of microplastics in the Arcticregion

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Geoscience Frontiers 2023年第4期14卷 187-199页

作者： Yulan Zhang Tanguang Gao Shichang Kang Deonie Allen Zhaoqing Wang Xi Luo Ling Yang jinlei chen Zhaofu Hu Pengfei chen Wentao Du Steve Allen State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China School of Geography Earth and Environmental SciencesUniversity of BirminghamEdgbastonBirminghamB152TTUK School for Resource and Environmental Studies Dalhousie UniversityHalifaxNova Scotia B3H 4R2Canada University of Chinese Academy of Sciences Beijing 100049China

Microplastics(MPs)pollution has become a serious environmental issue of growing global concern due to the increasing plastic production and usage.Under climate warming,the cryosphere,defined as the part of Earth’s layer characterized by the low temperatures and the presence of frozen water,has been experiencing significant changes.The Arctic cryosphere(e.g.,sea ice,snow cover,Greenland ice sheet,permafrost)can store and release pollutants into environments,making Arctic an important temporal sink and source of MPs.Here,we summarized the distributions of MPs in Arctic snow,sea ice,seawater,rivers,and sediments,to illustrate their potential sources,transport pathways,storage and release,and possible effects in this sentinel region.Items concentrations of MPs in snow and ice varied about 1-6 orders of magnitude in different regions,which were mostly attributed to the different sampling and measurement methods,and potential sources of MPs.MPs concentrations from Arctic seawater,river/lake water,and sediments also fluctuated largely,ranging from several items of per unit to>40,000 items m^(-3),100 items m^(-3),and 10,000 items kg^(-1) dw,respectively.Arctic land snow cover can be a temporal storage of MPs,with MPs deposition flux of about(4.9-14.26)×10^(8) items km^(-2) yr^(-1).MPs transported by rivers to Arctic ocean was estimated to be approximately 8-48 ton/yr,with discharge flux of MPs at about(1.65-9.35)×10^(8) items/s.Average storage of MPs in sea ice was estimated to be about 6.1×10^(18) items,with annual release of about 5.1×10^(18) items.Atmospheric transport of MPs from long-distance terrestrial sources contributed significantly to MPs deposition in Arctic land snow cover,sea ice and oceanic surface waters.Arctic Great Rivers can flow MPs into the Arctic Ocean.Sea ice can temporally store,transport and then release MPs in the surrounded environment.Ocean currents from the Atlantic brought high concentrations of MPs into the Arctic.However,there existed large uncertainties of estimation on the storage and re

关键词： Microplastics Arctic Sea ice Snow Seawater Sediments

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Plant above-ground biomass and litter quality drive soil microbial metabolic limitations during vegetation restoration of subtropical forests

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Soil Ecology Letters 2023年第2期5卷 103-115页

作者： Shuo Zhang Ying-Ping Wang Xi Fang jinlei chen Nannan Cao Pingping Xu Mengxiao Yu Xin Xiong Xiangping Tan Qi Deng Junhua Yan Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China University of Chinese Academy of Sciences Beijing 100049China CSIRO Oceans and Atmosphere PMB 1AspendaleVictoria 3195Australia Faculty of Life Science and Technology Central South University of Forestry and TechnologyChangsha 410004China

Changes in litter quality(carbon:nitrogen,C:N)and above-ground biomass(AGB)following vegetation restoration significantly impact soil physicochemical properties,yet their effects on soil microbial metabolic limitations remain unclear.We measured litter quality,AGB,soil physicochemical properties,and extracellular enzyme activity(EEA)along a vegetation restoration gradient(7,14,49,70 years,and nearly climax evergreen broadleaved forests)in southern China.We also evaluated soil microbial metabolic limitations by a vector analysis of the EEA.Results revealed the soil microbial metabolisms were co-limited by C and phosphorus(P).The microbial C limitation initially decreased(before 14 years)and then increased,while the microbial P limitation initially increased(before 49 years)and then decreased.Partial least squares path modeling(PLS-PM)showed that the microbial C limitation was mainly attributed to microbial C use efficiency induced by litter quality,suggesting that microorganisms may transfer cellular energy between microbial growth and Cacquiring enzyme production.The microbial P limitation was primarily correlated with AGB-driven change in soil elements and their stoichiometry,highlighting the importance of nutrient stoichiometry and balance in microbial metabolism.The shifts between microbial C and P limitations and the strong connections of plant–soil-microbe processes during vegetation restoration revealed here will provide us with helpful information for optimal management to achieve forest restoration success.

关键词： Extracellular enzymatic stoichiometry Microbial metabolic limitations Above-ground biomass Litter quality Vegetation restoration Subtropic

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The evapotranspiration and environmental controls of typical underlying surfaces on the Qinghai-Tibetan Plateau

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Research in Cold and Arid Regions 2021年第1期13卷 53-61页

作者： jinlei chen Jun Wen ShiChang Kang XianHong Meng XianYu Yang State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China Key Laboratory of Land Surface Processes and Climate Change Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China CAS Centre for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China College of Atmospheric Sciences Chengdu University of Information TechnologyChengduSichuan 610225China

To reveal the characteristics of evapotranspiration and environmental control factors of typical underlying surfaces(alpine wetland and alpine meadow)on the Qinghai-Tibetan Plateau,a comprehensive study was performed via in situ observations and remote sensing data in the growing season and non-growing season.Evapotranspiration was positively correlated with precipitation,the decoupling coefficient,and the enhanced vegetation index,but was energy-limited and mainly controlled by the vapor pressure deficit and solar radiation at an annual scale and growing season scale,respectively.Compared with the non-growing season,monthly evapotranspiration,equilibrium evaporation,and decoupling coefficient were greater in the growing season due to lower vegetation resistance and considerable precipitation.However,these factors were restricted in the alpine meadow.The decoupling factor was more sensitive to changes of conductance in the alpine wetland.This study is of great significance for understanding hydro-meteorological processes on the Qinghai-Tibetan Plateau.

关键词： evapotranspiration control factor typical underlying surfaces Qinghai-Tibetan Plateau

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昆布多糖-聚合氯化铝铁复配去除水中聚乙烯微塑料

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环境化学 2024年第4期43卷 1401-1410页

作者：陈金垒龚佳昕陈锦莉黄华斌厦门华厦学院环境与公共健康学院厦门361024

以昆布多糖(LA)作为一种新型助凝剂,考察了其在使用聚合氯化铝铁(PAFC)去除聚乙烯(PE)微塑料时的强化混凝性能,通过Zeta电位、扫描电镜(SEM)、傅里叶变换红外光谱(FTIR)、X射线光电子能谱(XPS)对混凝机理进行了研究,结果表明,添加适量... 详细信息

以昆布多糖(LA)作为一种新型助凝剂,考察了其在使用聚合氯化铝铁(PAFC)去除聚乙烯(PE)微塑料时的强化混凝性能,通过Zeta电位、扫描电镜(SEM)、傅里叶变换红外光谱(FTIR)、X射线光电子能谱(XPS)对混凝机理进行了研究,结果表明,添加适量的LA可提高PAFC对PE微塑料的混凝效率,当PAFC和LA的投加量分别为150 mg·L^(−1)和20 mg·L^(−1)时,单一PAFC和PAFC-LA对PE微塑料的的去除率分别达到78.4%和95.2%.PAFC和PAFC-LA对PE微塑料的混凝机理是一致的,LA的加入显著改善PAFC的电荷中和、吸附架桥和卷扫絮凝效果.不同pH、微塑料粒径、共存离子、腐殖酸共存及真实水体效果测试实验表明,PAFC-LA复配混凝系统具有较好的环境适应性.

关键词：聚合氯化铝铁昆布多糖聚乙烯微塑料机理

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聚酰胺微塑料对十二烷基苯磺酸钠的吸附

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化工环保 2024年第1期44卷 60-67页

作者：陈金垒章雨晨陈雅婷黄华斌厦门华厦学院环境与公共健康学院福建厦门361024

考察了聚酰胺(PA)微塑料对溶液中十二烷基苯磺酸钠(SDBS)的吸附性能,采用SEM、FTIR和XPS等手段表征了吸附前后PA微塑料的变化,探讨了PA微塑料对SDBS的吸附机理。实验结果表明:PA微塑料对SDBS的吸附过程符合准二级动力学模型和Langmuir... 详细信息

考察了聚酰胺(PA)微塑料对溶液中十二烷基苯磺酸钠(SDBS)的吸附性能,采用SEM、FTIR和XPS等手段表征了吸附前后PA微塑料的变化,探讨了PA微塑料对SDBS的吸附机理。实验结果表明:PA微塑料对SDBS的吸附过程符合准二级动力学模型和Langmuir等温吸附模型;25℃时,PA微塑料对SDBS的饱和吸附量为10.896mg/g;随着pH的增加,PA微塑料对SDBS的吸附能力逐渐降低;CO_(3)^(2-)对PA微塑料吸附SDBS的过程具有明显的抑制作用。PA微塑料吸附SDBS的机理包括PA中的羰基与SDBS的苯环发生的n-π电子供受体(EDA)作用、PA中的氨基与SDBS的磺酸基发生的氢键作用、静电作用和孔隙填充作用。

关键词：聚酰胺微塑料十二烷基苯磺酸钠吸附机理

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基于左心室和冠状动脉动态体模系统观察不同心率下CT图像重建最佳期相

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中国医学影像技术 2024年第6期40卷 917-921页

作者：陈金磊李洪杰陈明山王学民天津市泰达医院医疗设备部天津300457 天津市泰达医院医学影像科天津300457 天津大学精密仪器与光电子工程学院天津300072 天津市生物医学检测技术与仪器重点实验室天津300072

目的观察以左心室和冠状动脉动态体模系统模拟左心室及冠状动脉运动时在不同心率下重建CT图像的最佳期相。方法构建可模拟50~120次/分心率下心脏周期性运动及心电信号输出的左心室和冠状动脉动态体模系统。于体模系统R-R间期行CT扫描,0~... 详细信息

目的观察以左心室和冠状动脉动态体模系统模拟左心室及冠状动脉运动时在不同心率下重建CT图像的最佳期相。方法构建可模拟50~120次/分心率下心脏周期性运动及心电信号输出的左心室和冠状动脉动态体模系统。于体模系统R-R间期行CT扫描,0~90%期相范围内每10%间隔重建图像。评估观察者间主观评估图像质量结果的一致性;对不同心率、不同期相图像进行比较。结果观察者间主观评价图像质量结果的一致性较高(Kendall W=0.83,P<0.05)。设定体模心率为50~60次/分时,大部分期相下重建图像质量均为良好,尤以30%、70%及80%期相最佳(P均<0.05);心率为65~75次/分时,最佳重建期相为40%、70%及80%(P均<0.05),以舒张期图像质量较好;心率80~95次/分时,30%为最佳重建期相(P均<0.05);心率为100次/分及以上时,所有期相重建图像质量均较差。结论以左心室和冠状动脉动态体模系统模拟左心室及冠状动脉运动时,不同心率下CT图像最佳重建期相不同;心率高于100次/分后所有重建图像质量均不佳。

关键词：心脏体模显像术体层摄影术 X线计算机图像质量

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聚合硫酸铁对水中聚乙烯微塑料的混凝效果与机理研究

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安全与环境学报 2024年第2期24卷 695-702页

作者：陈金垒龚佳昕苏善煜黄华斌厦门华厦学院环境与公共健康学院福建厦门361024

以聚合硫酸铁(Polyferric Sulfate,PFS)和聚乙烯(Polyethylene,PE)微塑料分别作为混凝剂和去除对象,通过改变混凝剂投加量、微塑料粒径、溶液pH值及共存污染物等系统地研究不同条件下PFS对PE微塑料的去除性能。采用X射线光电子能谱(X-ra... 详细信息

以聚合硫酸铁(Polyferric Sulfate,PFS)和聚乙烯(Polyethylene,PE)微塑料分别作为混凝剂和去除对象,通过改变混凝剂投加量、微塑料粒径、溶液pH值及共存污染物等系统地研究不同条件下PFS对PE微塑料的去除性能。采用X射线光电子能谱(X-ray Photoelectron Spectroscopy,XPS)、傅里叶变换红外光谱(Fourier Transform Infrared Spectroscopy,FT-IR)、扫描电子显微镜(Scanning Electron Microscope,SEM)和Zeta电位分析方法初步探讨混凝机理。结果显示:当PFS投加质量浓度为10~550 mg/L时,PE微塑料的去除率随着PFS投加质量浓度的增加而呈升高趋势;加入表面活性剂及碱性条件下,PFS具有更好的混凝沉降性能;在小于500μm的粒径中,PE微塑料粒径为50~150μm时的去除率最高;当混凝剂投加质量浓度为550 mg/L,pH值为8时,去除率可达到98.0%,且优于铝系和天然混凝剂。在六价铬-微塑料共存体系中,微塑料的去除效果未受到显著影响。同时,混凝剂对六价铬的最大去除率可达到15.9%。混凝机理分析表明,电荷中和和吸附架桥作用为PFS对PE微塑料的主要混凝机制。

关键词：环境工程学聚合硫酸铁聚乙烯微塑料混凝机理

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