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Land use change and its driving factors in the ecological function area:A case study in the Hedong Region of the Gansu Province,China

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Journal of Arid Land 2024年第1期16卷 71-90页

作者： WEI Zhudeng DU Na yu wenzheng School of Geographical Science Nanjing University of Information Science&TechnologyNanjing 210044China

Land use and cover change(LUCC)is important for the provision of ecosystem *** increasing number of recent studies link LUCC processes to ecosystem services and human well-being at different scales ***,the dynamic of land use and its drivers receive insufficient attention within ecological function areas,particularly in quantifying the dynamic roles of climate change and human activities on land use based on a long time *** study utilizes geospatial analysis and geographical detectors to examine the temporal dynamics of land use patterns and their underlying drivers in the Hedong Region of the Gansu Province from 1990 to *** indicated that grassland,cropland,and forestland collectively accounted for approximately 99% of the total land *** initially increased and then decreased after 2000,while grassland decreased with *** contrast,forestland and construction land were continuously expanded,with net growth areas of 6235.2 and 455.9 km^(2),*** 1990 to 2020,cropland was converted to grassland,and both of them were converted to forestland as a *** expansion of construction land primarily originated from *** 2000 to 2005,land use experienced intensified temporal dynamics and a shift of relatively active zones from the central to the southeastern *** yield,economic factors,and precipitation were the major factors accounting for most land use *** impacts on land use changes were stronger before 1995,succeeded by the impact of animal husbandry during 1995-2000,followed by the impacts of grain production and gross domestic product(GDP)after ***,agricultural and pastoral activities,coupled with climate change,exhibited stronger enhancement effects after 2000 through their interaction with population and economic *** patterns closely correlated with ecological restoration projects in China since *** study implies the importance of synergy be

关键词： land use land type geographic detector driving mechanism Hedong Region

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Less pressure contributes to gravity-driven membrane ultrafiltration with greater performance:Enhanced driving efficiency and reduced disinfection by-products formation potential

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Journal of Environmental Sciences 2024年第3期137卷 407-419页

作者： Xiaoting Wu yufei Li Zhaoyang Su Long Tian Muhammad Saboor Siddique wenzheng yu Colleges of Forestry Northeast Forestry UniversityHarbin 150040China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Gravity-driven membrane(GDM)systems have been well developed previously;however,impacts of driving(i.e.,transmembrane)pressure on their performance received little attention,which may infuence GDM *** this study,we evaluated 4 GDM systems via altering the transmembrane pressure from 50 mbar to 150 mbar with 2 groups,treating surface water in Beijing,*** showed that less driving pressure was more ***,compared to groups(150 mbar),groups under a pressure of 50 mbar were found to have greater normalized permeability and lower total *** the whole operation period,the quality of effuents was gradually *** example,the removal efficiency of UV254was significantly improved;particularly,under low driving pressure,the removal efficiency of UV254in PES GDM system increased by 11.91%,as compared to the corresponding system under high driving *** observation was consistent with the reduction on disinfection by-products(DBPs)formation potential;groups under 50 mbar achieved better DBPs potential control,indicating the advantages of lower driving *** were analyzed and responsible for these differences,and distinct distributions of bacteria communities of two GDM systems under 50 and 150 mbar may be responsible for various humic-like substances removal ***,GDM systems under less pressure should be considered and expected to provide suggestions on the design of GDM systems in real applications.

关键词： Ultrafiltration Gravity driven operation Membrane fouling Biofilms Disinfection by-products

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Spatial and Temporal Distribution Characteristics of Solar Energy Resources in Tibet

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Energy Engineering 2024年第1期121卷 43-57页

作者： Yanbo Shen Yang Gao yueming Hu Xin Yao wenzheng yu yubing Zhang Public Meteorological Service Center China Meteorological AdministrationBeijing100081China Center forWind and Solar Energy Resources China Meteorological AdministrationBeijing100081China School of Applied Meteorology Nanjing University of Information Science&TechnologyNanjing210044China School of Geographical Sciences Nanjing University of Information Science&TechnologyNanjing210044China

The Tibet Plateau is one of the regions with the richest solar energy resources in the *** the process of achieving carbon neutrality in China,the development and utilization of solar energy resources in the region will play an important *** this study,the gridded solar resource data with 1km resolution in Tibet were obtained by spatial correction and downscaling of SMARTS *** this basis,the spatial and temporal distribution characteristics of solar energy resources in the region in the past 30 years(1991–2020)are finely evaluated,and the annual global horizontal radiation resource is *** results show that:1)The average annual global horizontal radiation amount in Tibet is 1816 kWh/m^(2).More than 60%of the area belongs to the“Most abundant”(GHI≥1750 kWh/m^(2))area of China’s solar energy resources category A,and nearly 40%belongs to the“Quite abundant”(1400≤GHI<1750)area of China’s solar energy resource category B.2)In space,the solar energy resources in Tibet increased gradually from north to south and from east to ***,Central and Eastern Shigatse,Shannan,and Southwestern Ali are the most abundant cities,with a maximum annual radiation level of 2189 kWh/m2.3)In terms of time,the total horizontal radiation in Tibet was the highest in May and the lowest in December.74%of the total area belongs to the“Very stable”(R_(w)≥0.47)area of solar resource stability category A,and 26%belongs to the“stable”(0.36≤R_(w)<0.47)area of solar resource stability category *** energy resources in the region show the characteristics of both strong and *** solar energy resources in the region have shown a fluctuating downward trend over the past 30 years,with an average decline of about 12.86(kWh/m2)per decade.4)In terms of solar radiation resources reaching the earth’s surface,the theoretical total amount of annual horizontal radiation in Tibet is about 240.07 billion tons of standard coal or 222.91 billion kilowatts on average.

关键词： Tibet solar resource spatiotemporal distribution

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The variation of DOM during long distance water transport by the China South to North Water Diversion Scheme and impact on drinking water treatment

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 85-100页

作者： Hankun Yang yujuan Li Hongyu Liu Nigel J.D.Graham Xue Wu Jiawei Hou Mengjie Liu Wenyu Wang wenzheng yu State Key Laboratory of Environmental Aquatic Chemistry Key Laboratory of Drinking Water Science and TechnologyResearch Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China School of Environment and Municipal Engineering Qingdao Technological UniversityQingdao266033China Colleges of Forestry Northeast Forestry UniversityHarbin150006China Department of Civil and Environmental Engineering Imperial College LondonSouth Kensington CampusLondonSW7 2AZUK School of Chemistry and Chemical Engineering Beijing Institute of TechnologyBeijing100081China State Key Laboratory of Separation Membrane Processes School of Environment Science and EngineeringTiangong UniversityTianjin300387China

In this study,samples were taken from three locations,upstream to downstream,along the central route project of the China South to North Water Diversion(SNWD)scheme in summer and *** were used to reveal the variations of dissolved organic matter(DOM)during the water transfer process,and the effects of these variations on drinking water treatment and disinfection by-products formation potential(DBPs-FP).The results showed that polysaccharides accumulate in summer and reduce in winter with flow distance,which has an important effect on the overall properties of DOM,as well as on the performance of coagulation,ultrafiltration,and the formation of *** substances,and their hydrophilic content,also increased in summer and decreased in winter with flow *** contrast,the concentration of small organic substances(MW≤1000 Da)increased in both summer and winter with flow distance,which affected both nanofiltration(NF)membrane fouling and *** results provide a useful case study of spatial and temporal changes in raw water DOM during long distance water transfer and their impact on the treatment and quality of drinking water from the SNWD.

关键词： Long-distance water transfer The China South to North Water Diversion Scheme Coagulation Membrane filtration Disinfection by-products

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The influence of various additives on coagulation process at different dosing point:From a perspective of structure properties

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Journal of Environmental Sciences 2021年第3期33卷 168-176页

作者： yufei Li Lei Xu Tong Shi wenzheng yu Colleges of Forestry Northeast Forestry UniversityHarbin 150040China Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100086China

Structure properties of flocs(size,fractal dimension(D_(f)),etc.)have a high impact on coagulation *** this work,the influences of three different additives(ferric salt(Fe),phosphate(P),and citric acid(CA))on coagulation process/efficiency were *** showed that a small amount of extra Fe can facilitate the growth of Al flocs by providing more'active sites'.Although zeta potential and D_(f) showed a limited change,the average floc size increased apparently and the increment was more obvious when Fe was added after the formation of the *** contrast,P addition during the rapid mixing period will decrease the final average floc size,while the influence is less significant when P was added after the growth of the *** terms of CA,a more striking negative effect on the growth ability of the flocs was observed compared to *** strong complexing/coordination interactions between CA and aluminum hydroxide is the main reason behind the *** also significantly decreased the D_(f) value of the flocs compared to P,and D_(f) showed a comparatively higher decrease when P or CA was added during the rapid mixing stage compared to the addition after the flocs *** results indicated that the addition of CA or P during the rapid mixing stage'inactivated'or occupied more'active sites'on the preliminarily formed Al NPs during the hydrolysis process,and therefore presented stronger impact on the morphology/size of the formed flocs.

关键词： Coagulation Floc size Additives Fractal dimension Zeta potential

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青海高原温性草原对气候变化和人类活动响应动态机制研究

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地理研究 2024年第8期43卷 1941-1957页

作者：俞文政周雅文魏柱灯姚鑫张玉冰南京信息工程大学地理科学学院南京210044

温性草原作为维护青海高原草畜平衡和生态安全的重点区域,对气候变化和人类活动极为敏感。本文依托GEE平台构建长时序、高精度的草地类型数据,结合气候数据,引入随机森林模拟气候因素与温性草原间的非线性关系,对传统残差分析进行改进,... 详细信息

温性草原作为维护青海高原草畜平衡和生态安全的重点区域,对气候变化和人类活动极为敏感。本文依托GEE平台构建长时序、高精度的草地类型数据,结合气候数据,引入随机森林模拟气候因素与温性草原间的非线性关系,对传统残差分析进行改进,以此探究青海高原温性草原的时空演变及其驱动因素。结果表明:①1987—2020年青海高原温性草原面积呈显著增长趋势,主要上升区域为共和盆地、茶卡盆地、柴达木盆地东侧等,下降区域仅占21.4%。②青海高原温性草原面积与气温和降水间呈正相关的区域占比为58.1%和67.3%,其中显著相关区域均在15%以上,可见气候的暖湿化对温性草原面积增加具有促进作用。③青海高原温性草原面积增加主要受气候变化与人类活动的共同影响,其中气候变化和人类活动相对贡献超过75%的区域分别占比33.1%和32.6%,集中于研究区东部和南部;而温性草原面积减少的主导因子为人类活动,主要分布于黄河流域,青海湖沿岸的部分区域。青海高原温性草原的时空变化及其驱动因素的定量研究结果可为草地可持续发展和政策制定提供支撑。

关键词：温性草原驱动因素随机森林残差分析青海高原

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Removal of F- and organic matter from coking wastewater by coupling dosing FeCl3 and AlCl3

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Journal of Environmental Sciences 2021年第12期33卷 2-11页

作者： Shuo Li Mengjie Liu Fuming Meng Xia Hu wenzheng yu College of Resource and Environmental Engineering Guizhou UniversityGuiyang 550025China Key Laboratory of Drinking Water Science and Technology Research Centre for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100086China Jinan Municipal Engineering Design&Research Institute(Group)Co.LTD China

Coagulation and precipitation is a widely applied method to remove F-from *** this work,the effect of coagulation on the removal of F-and organic matter from coking wastewater was studied using Al Cl3and Fe Cl3as compound *** removal rates of F-and organic matter under different coagulant doses and p H conditions were *** results show that the highest removal rates of F-by Al Cl3and Fe Cl3are 94.4%and 25.4%,respectively;when the dosage is 10 mmol/L,the TOC removal rates of Fe Cl3and Al Cl3reach 20.4%and 34.7%,***,the removal rate of F-by Al Cl3is higher than that of Fe Cl3,but the removal rate of organic matter by Fe Cl3is relatively *** addition of Ca2+can promote the removal of F-,but the removal rate of organic matter *** addition,by investigating the effects of different p H and Fe–Al ratio on the removal rate,the removal effect of adding Fe Cl3and Al Cl3at the same time was *** results show that the most suitable working condition for the removal of organic matter and F-is that the p H is 6.5 and the molar ratio of Al/Fe is 8:***,the removal mechanism of F-and organic matter in coking wastewater by Fe Cl3and Al Cl3was explored in this *** experimental results can provide reference for the advanced treatment of coking wastewater.

关键词： Coagulation Coking wastewater Fluoride Organic matter

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基于时程分析方法的黏滞阻尼减震结构附加阻尼比计算研究

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建筑钢结构进展 2024年第2期26卷 54-63页

作者：兰香张兴仙潘文余文正张龙飞吴克川昆明学院建筑工程学院昆明650214 昆明学院工程抗震减灾研究所昆明650214 云南开放大学&云南国防工业职业技术学院城市建设学院昆明650032 昆明理工大学建筑工程学院昆明650051

附设黏滞阻尼器后结构的附加阻尼比是进行减震结构设计的关键。基于目前计算附加阻尼比时应用得十分广泛的时程分析方法进行研究,首先从基本理论出发,分析基于特征向量法的快速非线性分析(FNA)方法、Ritz向量法的FNA方法、直接积分方法... 详细信息

附设黏滞阻尼器后结构的附加阻尼比是进行减震结构设计的关键。基于目前计算附加阻尼比时应用得十分广泛的时程分析方法进行研究,首先从基本理论出发,分析基于特征向量法的快速非线性分析(FNA)方法、Ritz向量法的FNA方法、直接积分方法以及与3种计算方法对应的能量比法在附加阻尼比计算时所面临的主要问题及重要参数设置;然后通过一单自由度体系的振动台试验测试结果与各种计算方法的数值模拟结果进行对比分析,得到较为适合的附加阻尼比计算方法;最后将研究成果应用于实际工程结构,进一步验证所推荐方法和参数设置的正确合理性。研究旨在为今后广大一线减震设计工程师计算较为真实的附加阻尼比提供重要参考。

关键词：消能减震结构黏滞阻尼器附加阻尼比时程分析方法振动台试验

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考虑周期折减的结构弹性时程分析调整方法

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地震工程学报 2024年第3期46卷 548-556,583页

作者：吴克川陶忠潘文兰香余文正张龙飞昆明学院建筑工程学院云南昆明650214 昆明理工大学建筑工程学院云南昆明650500

针对结构弹性时程分析时无法考虑周期折减的问题展开研究,通过对比结构时程分析的过程中,地震波的选取是否考虑周期折减的差异,提出采用增大系数放大时程分析法输入地震波有效峰值加速度以及地震响应;考虑弹性时程分析过程中,周期折减... 详细信息

针对结构弹性时程分析时无法考虑周期折减的问题展开研究,通过对比结构时程分析的过程中,地震波的选取是否考虑周期折减的差异,提出采用增大系数放大时程分析法输入地震波有效峰值加速度以及地震响应;考虑弹性时程分析过程中,周期折减对结构地震作用的增大效应。理论分析增大系数取值的影响因素,并基于单自由度体系对比两种调整方法的效果及差异,采用实际算例以验证所提出弹性时程分析中考虑周期折减调整方法的有效性。结果表明:增大系数的取值与周期折减系数、结构自振周期及场地特征周期等因素有关;对于单自由度体系,两种调整方法具有完全相同的调整效果;按文章提出方法考虑周期折减的算例结构,弹性时程分析所得各楼层地震剪力及层间位移角与考虑周期折减的反应谱(CQC)计算结果均较为接近。

关键词：弹性时程分析周期折减增大系数反应谱地震波调整

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Unraveling Membrane Fouling Induced by Chlorinated Water Versus Surface Water:Biofouling Properties and Microbiological Investigation

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Engineering 2022年第8期8卷 154-164页

作者： Li Zhang Lei Xu Nigel Graham wenzheng yu State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Department of Civil and Environmental Engineering Imperial College LondonSouth Kensington CampusLondon SW72AZUK

Chlorine is usually applied in the urban water treatment process to deactivate pathogens and prevent waterborne *** a pre-treatment,it remains unclear whether chlorinated water can effectively alleviate membrane fouling during ultrafiltration(UF).In this study,tap water was investigated for its effect on biofilm formation and biofouling in a gravity-driven membrane(GDM)filtration *** comparison,biofilm/biofouling with untreated surface(lake)water was studied in *** was found that more severe membrane fouling occurred with the filtration of tap water than lake water,and larger quantities of polysaccharide and extracellular DNA(eDNA)were present in the tap-water biofilm than in the lake-water *** tap-water biofilm had a densely compact *** contrast,a porous,spider-like structure was observed for the lake-water biofilm,which was assumed to be associated with the bacteria in the *** hypothesis was verified by 16S ribosomal RNA(rRNA)sequencing,which demonstrated that Xanthobacter was the dominant taxon in the tap-water ***,membrane hydrophobicity/hydrophilicity played a minor role in affecting the membrane fouling properties and microbial *** study revealed the significant role of chlorine-resistant bacteria in biofouling formation and provides a deeper understanding of membrane fouling,which can potentially aid in searching for effective ways of controlling membrane fouling.

关键词： Membrane fouling Biofilm GDM filtration technology Ultrafiltration Chlorine-resistant bacteria Hydrophilicity

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