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Characteristics and influencing factors of greenhouse gas emissions from reservoirs in the Yellow River Basin:A Meta-analysis

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Science China Earth Sciences 2024年第7期67卷 2210-2225页

作者： Shurui HUANG Peijia ZHANG Wenxiu ZHENG Jiajia ZHANG Yang LI Yuanjian WANG Enhui JIANG Shaoda LIU Xinghui XIA State Key Laboratory of water environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 00875China Yellow River Institute of Hydraulic Research Yellow River Conservancy CommissionZhengzhou 450003China

Reservoir construction and operation profoundly alter the hydrological,hydrodynamic,and carbon and nitrogen cycling processes of ***,current research still lacks a systematic understanding of the characteristics of greenhouse gas(GHG)emissions from reservoirs in arid/semi-arid *** study integrates existing monitoring data to discuss the characteristics of GHG emissions from reservoirs in the Yellow River Basin and illustrate the controlling factors and underlying mechanism of these *** results indicate that while CO_(2) emission flux from reservoirs is lower than that from river channels,the emission fluxes of CH_(4) and N_(2)O are 1.9 times and 10 times those from rivers,respectively,indicating that the emission of GHG with stronger radiative effect is significantly enhanced in *** to the reservoirs in humid climates(e.g.,the Three Gorges Reservoir),reservoirs in the Yellow River Basin exhibit relatively lower emissions of CO_(2) and CH_4 due to lower organic matter concentrations,but significantly higher N_(2)O emissions due to higher nitrogen *** Carlo simulations for 237 reservoirs in the Yellow River Basin showed that total emission of the three GHGs is 3.05 Tg CO_(2)-eq yr^(-1),accounting for 0.39% of the total emission from global reservoirs and lower than the area percentage of the basin(0.53%).This study has important implications on revealing the GHG emission characteristics and control mechanisms of reservoirs in arid/semi-arid regions.

关键词： Yellow River Basin Reservoir Greenhouse gas Emission flux water quality

Stability behavior of the Lanxi ancient flood control levee after reinforcement with upside-down hanging wells and grouting curtain

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Journal of Mountain Science 2024年第1期21卷 84-99页

作者： QIN Zipeng TIAN Yan GAO Siyuan ZHOU Jianfen HE Xiaohui HE Weizhong GAO Jingquan school of water conservancy and environment Engineering Zhejiang University of Water Resources and Electric PowerHangzhou 310018China Department of Civil Engineering Imperial College LondonLondonSW71BFEngland Lanxi water Affairs Bureau Lanxi 321102China Zhejiang water conservancy Engineering Consulting Co. LtdHangzhou 310051China

The stability of the ancient flood control levees is mainly influenced by water level fluctuations, groundwater concentration and rainfalls. This paper takes the Lanxi ancient levee as a research object to study the evolution laws of its seepage, displacement and stability before and after reinforcement with the upside-down hanging wells and grouting curtain through numerical simulation methods combined with experiments and observations. The study results indicate that the filled soil is less affected by water level fluctuations and groundwater concentration after reinforcement. A high groundwater level is detrimental to the levee's long-term stability, and the drainage issues need to be fully considered. The deformation of the reinforced levee is effectively controlled since the fill deformation is mainly borne by the upside-down hanging wells. The safety factors of the levee before reinforcement vary significantly with the water level. The minimum value of the safety factors is 0.886 during the water level decreasing period, indicating a very high risk of the instability. While it reached 1.478 after reinforcement, the stability of the ancient levee is improved by a large margin.

关键词： Stability analysis Multiple factors Antiseepage reinforcement Upside-down hanging well Grouting curtain Ancient levee

Unlocking the potential of thin-film composite reverse osmosis membrane performance:Insights from mass transfer modeling

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Chinese Chemical Letters 2024年第5期35卷 66-76页

作者： Kexin Yuan Yulei Liu Haoran Feng Yi Liu Jun Cheng Beiyang Luo Qinglian Wu Xinyu Zhang Ying Wang Xian Bao Wanqian Guo Jun Ma State Key Laboratory of Urban water Resource and environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China College of Architecture and environment Sichuan UniversityChengdu 610065China school of Municipal and environmental Engineering Shandong Jianzhu UniversityJi’nan 250101China College of water conservancy and Hydropower Engineering Sichuan Agricultural UniversityYaan 625014China

Thin-film composite(TFC)reverse osmosis(RO)membranes have attracted considerable attention in water treatment and desalination processes due to their specific separation ***,the trade-off effect between water flux and salt rejection poses huge challenges to further improvement in TFC RO membrane *** research works have been dedicated to optimizing membrane fabrication and modification for addressing this *** the meantime,several reviews summarized these ***,the existing reviews seldom analyzed these methods from a theoretical perspective and thus failed to offer effective optimization directions for the RO process from the root *** this review,we first propose a mass transfer model to facilitate a better understanding of the entire process of how water and solute permeate through RO membranes in detail,namely the migration process outside the membrane,the dissolution process on the membrane surface,and the diffusion process within the ***,the water and salt mass transfer behaviors obtained from model deduction are comprehensively analyzed to provide potential guidelines for alleviating the trade-off effect between water flux and salt rejection in the RO ***,inspired by the theoretical analysis and the accurate identification of existing bottlenecks,several promising strategies for both regulating RO membranes and optimizing operational conditions are proposed to further exploit the potential of RO membrane *** review is expected to guide the development of high-performance RO membranes from a mass transfer theory standpoint.

关键词： Reverse osmosis Mass transfer model Trade-off effect Membrane performance Optimization strategies

Runoff change in the Yellow River Basin of China from 1960 to 2020 and its driving factors

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Journal of Arid Land 2024年第2期16卷 168-194页

作者： WANG Baoliang WANG Hongxiang JIAO Xuyang HUANG Lintong CHEN Hao GUO Wenxian school of water conservancy North China University of Water Resources and Electric PowerZhengzhou 450046China College of water Resources North China University of Water Resources and Electric PowerZhengzhou 450046China

Analysing runoff changes and how these are affected by climate change and human activities is deemed crucial to elucidate the ecological and hydrological response mechanisms of *** Indicators of Hydrologic Alteration and the Range of Variability Approach(IHA-RVA)method,as well as the ecological indicator method,were employed to quantitatively assess the degree of hydrologic change and ecological response processes in the Yellow River Basin from 1960 to *** Budyko's water heat coupling balance theory,the relative contributions of various driving factors(such as precipitation,potential evapotranspiration,and underlying surface)to runoff changes in the Yellow River Basin were quantitatively *** results show that the annual average runoff and precipitation in the Yellow River Basin had a downwards trend,whereas the potential evapotranspiration exhibited an upwards trend from 1960 to *** approximately 1985,it was reported that the hydrological regime of the main stream underwent an abrupt *** degree of hydrological change was observed to gradually increase from upstream to downstream,with a range of 34.00%-54.00%,all of which are moderate ***,significant differences have been noted among different ecological indicators,with a fluctuation index of 90.00%at the outlet of downstream hydrological stations,reaching a high level of *** the mutation,the biodiversity index of flow in the middle and lower reaches of the Yellow River was generally lower than that in the base *** research results also indicate that the driving factor for runoff changes in the upper reach of the Yellow River Basin is mainly precipitation,with a contribution rate of 39.31%-54.70%.Moreover,the driving factor for runoff changes in the middle and lower reaches is mainly human activities,having a contribution rate of 63.70%-84.37%.These results can serve as a basis to strengthen the protection and restoration efforts in the Yellow River Basin

关键词： Budyko theory hydrological regime attribution analysis ecological responses Yellow River climate change human activity runoff

Genetic relationship between formation,accumulation and migration and dispersion of peat materials in Paleogene——Take the Qiongdongnan Basin as an example

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Acta Oceanologica Sinica 2024年第4期43卷 80-91页

作者： Xiaojing Li Zengxue Li Dongdong Wang Guangzeng Song Pingli Wang Haiyan Liu Key Laboratory of Sedimentary Mineralization and Sedimentary Minerals in Shandong Province Qingdao 266590China Shandong University of Science and Technology Qingdao 266590China school of water conservancy and environment University of JinanJinan 250022China

Coal-type source rocks include both coal and terrigenous marine source *** studying the distribution of secondary depressions,uplifts,as well as the characteristics of peat formation and accumulation in the northern marginal sea basin of the South China Sea,and combining them with coal formation characteristics observed in other basins,five genetic theories on the relationship between peat accumulation and dispersed organic matter accumulation are *** northern marginal sea basin of the South China Sea is characterized by“disadvantageous coals formation and favorable terrigenous marine source rocks formation.”This paper provides a distribution map of coal seams and terrigenous marine source rocks in the Qiongdongnan Basin and determines their distribution *** shows that the migration of sedimentary facies in the basins and inner depressions led to the formation and migration of the peat accumulation *** addition,the vertical migration of the peat accumulation centers led to planar migration,which is actually a type of coupling *** research results have revealed that the formation of coal-type source rock is *** marginal sea basin is composed of several fault-depression basins,with each basin developing a second order of depression and *** is no unified basin center or depositional center to be *** a result,the concentration centers of coal-forming materials also vary *** on the distribution characteristics of coal-type source rocks in different basins within the marginal sea basins of the South China Sea,the research results have practical significance and provide guidance for exploring coal-type oil and gas reservoirs in this area.

关键词： Coal-type source rock marginal sea basins migration of peat aggregation centers terrigenous marine source rock Qiongdongnan Basin

Spatio-temporal Variation Characteristics of Extreme Climate Events and Their Teleconnections to Large-scale Ocean-atmospheric Circulation Patterns in Huaihe River Basin,China During 1959–2019

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Chinese Geographical Science 2024年第1期34卷 118-134页

作者： YAO Tian ZHAO Qiang WU Chuanhao HU Xiaonong XIA Chuan'an WANG Xuan SANG Guoqiang LIU Jian WANG Haijun school of water conservancy and environment University of JinanJinan250022China Yangtze Institute for Conservation and Development Hohai UniversityNanjing210098China Zijin school of Geology and Mining Fuzhou UniversityFuzhou350108China water Research Institute of Shandong Province Jinan250014China Shandong Provincial Bureau of Hydrology and water Resources Jinan250100China

Huaihe River Basin(HRB) is located in China’s north-south climatic transition zone,which is very sensitive to global climate *** on the daily maximum temperature,minimum temperature,and precipitation data of 40 meteorological stations and nine monthly large-scale ocean-atmospheric circulation indices data during 1959–2019,we present an assessment of the spatial and temporal variations of extreme temperature and precipitation events in the HRB using nine extreme climate indices,and analyze the teleconnection relationship between extreme climate indices and large-scale ocean-atmospheric circulation *** results show that warm extreme indices show a significant(P < 0.05) increasing trend,while cold extreme indices(except for cold spell duration) and diurnal temperature range(DTR) show a significant decreasing ***,all extreme temperature indices show significant mutations during ***,a stronger warming trend occurs in eastern HRB than western HRB,while maximum 5-d precipitation(Rx5day) and rainstorm days(R25) show an increasing trend in the southern,central,and northwestern regions of *** oscillation(AO),Atlantic multidecadal oscillation(AMO),and East Atlantic/Western Russia(EA/WR) have a stronger correlation with extreme climate indices compared to other circulation *** and AMO(EA/WR) exhibit a significant(P < 0.05) negative(positive)correlation with frost days and diurnal temperature *** warm events are strongly correlated with the variability of AMO and EA/WR in most parts of HRB,while extreme cold events are closely related to the variability of AO and AMO in eastern *** contrast,AMO,AO,and EA/WR show limited impacts on extreme precipitation events in most parts of HRB.

关键词： extreme climate indices Sen’s slope variation mutation test atmospheric circulation indices Pearson’s correlation analysis Huaihe River Basin(HRB),China

Large porewater exchange reshapes saltmarsh carbon and greenhouse gas budgets on local and global scales

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Science China Earth Sciences 2024年第7期67卷 2195-2209页

作者： Xiaogang CHEN Isaac RSANTOS Lucheng ZHAN Yu Yan YAU Yan ZHANG Ling LI Key Laboratory of Coastal environment and Resources of Zhejiang Province School of EngineeringWestlake UniversityHangzhou 310024China Department of Marine Sciences University of GothenburgGothenburg 41319Sweden College of water conservancy and Hydropower Engineering Hohai UniversityNanjing 210024China

Saltmarshes are carbon-rich ecosystems that play a role in climate regulation by efficiently sequestrating atmospheric CO_(2).Climate change is a major threat to saltmarshes and will impact saltmarsh carbon ***,porewater-derived carbon outwelling emerges as a crucial pathway for carbon sequestration,but it has been largely overlooked in ***,we assessed the drivers of dissolved carbon exports and greenhouse gas emissions in a saltmarsh and placed those observations into a global *** our study site,porewater exchange(PEX)was the major process controlling dissolved carbon and greenhouse gas *** our results with 33 other studies in saltmarshes worldwide,porewater-derived carbon fluxes were equivalent to~48% of average global saltmarsh primary productivity and 2.2 times greater than global organic carbon ***,our local observations and global upscaling demonstrate the major role played by PEX in saltmarsh carbon *** part of dissolved inorganic carbon returns to the atmosphere as CO_(2),the remaining bicarbonate fraction is stored in the ocean over long time *** findings strengthen global blue carbon assessments and build arguments for the use of saltmarshes as nature-based solutions for global climate change.

关键词： Coastal carbon Global carbon budget Carbon neutrality Nature-based solutions Coastal wetlands Submarine groundwater discharge

Production of the C/TiO_(2)composite with a high-performance electrochemical property from titanium-rich sludge via in-situ C coating

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Journal of environmental Sciences 2024年第3期137卷 131-143页

作者： Hualong Wu Yanxia Zhao Jiexi Wang Xiaoyan Li Kaimin Shih Xuguang Li Wei Liu school of water conservancy and environment University of JinanJinan 250022China State Key Lab of Physical Chemistry of Solid Surface Collaborative Innovation Center of Chemistry for Energy MaterialsCollege of MaterialsXiamen UniversityXiamen 361005China school of Metallurgy and environment Central South UniversityChangsha 410083China Department of Civil Engineering The University of Hong KongPokfulamHong KongChina Institute of environment and Ecology Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China

Resource recycling from waste-water and sludge is an important part of the 14th Five-Year Plan in *** emerging titanium-based coagulants have drawn growing attentions due to their strong coagulation capability in water purification and value-added Ti-loaded sludge *** and recovery of the high value-added sludge into functional nanomaterials is highly significant for both sludge reduction and environmental *** present study was carried out to investigate the recycle of the coagulated Ti-loaded sludge to produce functional C/TiO_(2)composites as the anode materials for lithium-ion batteries(LIBs).It is the first time that the application of the Ti-loaded wastewater sludge derived C/TiO_(2)was evaluated for *** experimental results showed that the carbon coating through in-situ carbonization of the sludge produced the C/TiO_(2)composites with a high specific surface area,stable structural integrity,and excellent electrochemical properties that would facilitate Li+diffusion in long-term LIBs *** C/TiO_(2)composites calcinated from the polytitanium sulfate-coagulated sludge at 800℃(N_(2))exhibited the best electrochemical performance during the cycling tests(601 m Ah/g at 100 m A/g after 200 cycles).The research work demonstrates the promising prospect of the recycle and value-added utilization of the Ti-loaded sludge in the production of high-performance C/TiO_(2)composites for energy storage *** study provides a new way for the management and reuse of Ti-loaded waste-sludge.

关键词： Sludge recovery Ti-loaded sludge In-situ coating Lithium-ion battery

Features and formulae of sediment incipient motion in vegetated flow environment

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Journal of Hydrodynamics 2024年第2期36卷 331-339页

作者： Yu-xuan Xu Wei-jie Wang Shi-bao Zhang Han-qing Zhao Xue-kai Chen Hai-ping Zhang school of water conservancy North China University of Water Resources and Electric PowerZhengzhou450045China State Key Laboratory of Simulation and Regulation of water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing100038China China Three Gorges Corporation Wuhan430010China

Aquatic vegetation is a vital component of natural river ecosystems,playing a crucial role in maintaining ecological balance,providing habitat and improving water ***,the presence of vegetation results in increased resistance in vegetated channels compared with non-vegetated channels,rendering traditional sediment movement predictions inadequate for the ***,the concept of a vegetation influence factor,denoted by CDah,has been proposed by previous researchers to represent the effect of vegetation on sediment movement in *** this study,we focus on exploring the vegetation resistance coefficient(CD)among the vegetation influence factors,evaluating two different calculation methods for vegetation resistance coefficient,and presenting two expressions through genetic algorithm analysis to predict the incipient flow velocity of sediment in vegetated *** predicted values from the new formulae show excellent agreement with measured data,highlighting the high accuracy of the proposed methods in predicting the incipient flow velocity of *** results provide a solid theoretical basis for understanding the influence of aquatic vegetation on sediment particle movement.

关键词： Vegetation flow vegetation resistance coefficient genetic algorithm sediment initiation