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Using Natural Radionuclides to Trace sources of Suspended Particles in the Lower Reaches of the Yellow River

Journal of Ocean University of China 2024年第1期23卷 99-108页

作者： ZHANG Han BURNETT CWilliam ZHANG Xiaojie ZHAO Shibin YANG Disong NAN Haiming YU Zhigang XU Bochao Frontiers Science Center for Deep Ocean Multispheres and Earth System and Key Laboratory of Marine Chemistry Theory and TechnologyMinistry of EducationOcean University of ChinaQingdao 266100China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China Department of Earth Ocean and Atmospheric ScienceFlorida State UniversityTallahasseeFL 32306USA North China Sea Environmental Monitoring Center State Oceanic AdministrationKey Laboratory of Ecological Prewarning and Protection of Bohai SeaMNRQingdao 266033China Shandong Provincial Key Laboratory of Marine Ecological Environment and Disaster Prevention and Mitigation Qingdao 266033China

Natural radionuclides are powerful tools for understanding the sources and fate of suspended particulate matter(SPM).Particulate matter with different particle sizes behaves differently with respect to adsorption and desorption.We analyzed the activi-ties and distribution characteristics of multiple natural radionuclides(238U,226Ra,40K,228Ra,7Be and 210Pbex)on size-fractionated SPM at the Lijin Hydrographic Station(Huanghe or Yellow River)every month over a one-year period.Results showed that medium silt(16–32µm)was the main component.As expected,the activity of each radionuclide decreased with an increase of particle size.We examined the sources of SPM with different particle sizes using activity ratios of 226Ra/238U,228Ra/226Ra,40K/238U and 7Be/210Pbex,and concluded that SPM with different particle sizes originated from different sources.Our results indicate that fine SPM(32µm)was mainly derived from resuspension of riverbed sediment.During high runoff periods,the concentration of SPM increased significantly,and the pro-portion of fine particles originating upstream increased.Naturally occurring radioactive isotopes,especially on size-fractionated par-ticles,are therefore seen as useful tracers to understand the sources and behaviors of riverine particles transported from land to sea.

关键词： the Yellow River suspended particulate matter size-fractions radionuclides sediment sources water elutriator

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Novel sediment source fingerprinting quantifying erosion-induced total nitrogen and total phosphorus outputs from an intensive agricultural catchment,North China

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International Soil and Water Conservation Research 2023年第3期11卷 494-506页

作者： Hanqing Yu Joseph Adu-Gyamfi Suarau Odutola Oshunsanya Adrian Chappell Wenxiang Liu Yu Zheng Tingting Xue Lee Heng Agricultural Clean Watershed Research Group Institute of Environment and Sustainable Development in AgricultureChinese Academy of Agricultural Sciences(CAAS)Haidian District100081BeijingChina International Atomic Energy Agency ViennaAustria Department of Agronomy University of IbadanNigeria School of Earth and Environmental Sciences Cardif UniversityCardifUK Chongqing Branch Institute Changjiang River Scientific Research InstituteChongqing400026China

Intensive farming is a primary cause of increased sediment and associated nitrogen(N)and phosphorus(P)loads in surface water systems.Determining their contributing sources,pathways and loads present major challenges in the high-intensity agricultural catchments.Herein,we quantify the sediment sources and magnitude of sediment total N and total P from different sources using a novel application of compound-specific stable isotope(CSSI)and fallout radionuclides(FRNs)of^(137)cs and^(210)pbex in an intensive agricultural catchment in North China.sediment sources from surface and sub-surface soils were estimated from FRNs fingerprint and accounted for 62±7%and 38±7%respectively,while surface soil from land uses that originated from hillslope were identified by CssI fingerprint.Using a novel application of FRNs and CSSI sediment fingerprinting techniques,the dominant sediment source was derived from maize farmland(44±0.1%),followed by channel bank(38±7%).The sedimentation rate(13.55±0.30 t ha^(-1)yr^(-1))was quantifed by the^(137)cs cores(0-60 cm)at the outlet of this catchment.The total N and total P in sediment were both mostly derived from maize farmland and least from channel banks.The channel banks are significant sediment sources but contribute little to the input of sediment N and P for eutrophication.It implies that chemically-applied farmlands are the main hotspots for catchment erosion control and pollution prevention.The novel application of FRNs and CSSI techniques cost-effectively quantified sediment N and P loads from different sources with a single visit to the catchment,enabling rapid assessment for optimizing soil conservation strategies and land management practices.

关键词： sediment sources Land use N and P loads Compound-specific stable isotope Falloutradionuclides

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sedimentation in small-scale irrigation schemes in Ethiopia: Its sources and management

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International Journal of sediment Research 2022年第5期37卷 576-588页

作者： Zerihun Anbesa Gurmu Henk Ritzema Charlotte de Fraiture Mekonen Ayana Water Resources Management Group Wageningen University Arba Minch University Department of Water Science and Engineering IHE Delft Institute for Water Education Adama Science and Technology University

Numerous irrigation schemes in sub-Saharan Africa(SSA) exhibit excessive sedimentation, resulting in underperformance and high maintenance costs. In the current study, a participatory monitoring program was used to investigate sediment causes and sources, measure the annual sediment load, and monitor desilting campaigns in two small scale irrigation schemes in Ethiopia, Arata-Chufa(100 ha) and Ketar(430 ha), for three years(2016-2018). sedimentation quantities were huge, where the annual river sediment influx ranged from 220 m3for the Arata-Chufa scheme to 1,741 m3for the Ketar scheme. On average 0.3 m3/m of sediment were removed from the main canal for Arata-Chufa costing 794 days of labor per year. In Ketar, sediment quantities were even greater: 1.1 m3/m was removed requiring 3,118days of labor per year. The sediment influx from the river source amounts to up to 95% for Arata-Chufa and moderately reaches 46% for Ketar, with the remainder of the sediment entering with overland erosion flows. Farmers reported increased sedimentation over time and difficulty paying operation and maintenance fees instead preferring to contribute labor for the desilting campaigns. sedimentation management is fragile and mainly involves frequent desilting campaigns and unharmonized efforts to reduce overland sediment inflows. Factors contributing to sediment deposition include mild longitudinal bed slopes, the location of the intake, canal layout, and lack of canal banks for protection against surface water inflow in addition to sub-optimal canal operations. Excessive sedimentation is a major challenge resulting in underperformance of numerous irrigation schemes in SSA, and the stakeholders’ lack of awareness of the sources of sedimentation is an underlying factor aggravating sedimentation problems. It is concluded that investigating the sources, extent, and types of sedimentation entering a small-scale irrigation scheme is the basis for reducing maintenance costs and for effective management of sedimentation problems.

关键词： sediment sources sediment management Irrigation performance Soil loss River sediment Erosion

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Slope-gully erosion relationship in small catchments of the middle reaches of the Yellow River

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Journal of Geographical Sciences 1999年第2期9卷 105-115页

作者： CHEN Hao(Institute of Geography, Chinese Academy of Sciences, Beijing 100101, China)

The slope-gully erosion relationship in small catchments of the middle reaches of the Yellow River has long been a topic concerned by relevant departments in China Slope-gully relationship in typical small catchment is determined determined on the concept of net increase of sediment yield by using analytical method of sediment formation at different positions in the catchment The result shows that sediments in a small catchment in the middle reaches of the Yellow River mainly come from slopes. ms paper indicated that the sediment sources from slopes are roughly 55, 60, 78 and 85 % of the total sediment yield of a small catchment in Yangdaogou. Wangjiagou. Jiuyuangou and Nanxiaohegou, respectively, due to impacts of varying degress from slope runoff.

关键词： small catchment slope-gully erosion relationship sediment sources the middle reaches of the Yellow River

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SOIL FINGERPRINTING IN THE PALOUSE BASIN, USA USING STABLE CARBON AND NITROGEN ISOTOPES

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International Journal of sediment Research 2003年第2期 278-284页

作者： Athanasios N. PAPANICOLAOU Jimmy.F. FOX John MARSHALL Albrook Hydraulics Lab Associate Professor Department of Civil and Environmental Engineering Department of Forest Resources Graduate Research Assistant ID 83844 Moscow University of Idaho Pullman WA 99164-2910 Washington State University

Stable carbon and nitrogen isotopic compositions of soils coupled with mean elemental measurements of carbon/nitrogen (C/N) are potentially powerful tools for identifying soil origin in a watershed. Specifically, stable carbon and nitrogen isotopic compositions of soils reflect the types of plants growing on them and the source of nitrogen, respectively. The C/N ratios reflect the presence of an active biological milieu altering the elemental composition of soils. The objectives of this paper are to use the stable isotope technique to distinguish between forest and agricultural soils found in the Palouse Watershed and examine the predictive ability and rigorousness of this method. The isotopic enrichment of forest and agriculture soil samples is determined via a mass spectrometer by comparing the isotopic ratio of soil samples with those of standard materials. The findings of this study indicate that in monoculture environments stable carbon isotopic compositions do not differ between forest and agricultural soils. Instead, stable nitrogen isotopic compositions along with the C/N measurements could provide a reliable fingerprinting tool.

关键词： Stable isotopes Geochemical tracers sediment sources Palouse watershed

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Rock magnetic properties of the fine-grained sediment on the outer shelf of the East China Sea:implication for provenance

Rock magnetic properties of the fine-grained sediment on the...

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中国科学院地质与地球物理研究所2003学术年会

作者： Jian Liu~(a,b,c,*),Rixiang Zhu~b,Guangxue Li~d a Qingdao Institute of Marine Geology,China Geological Survey,Qingdao 266071,PR China b Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100101,PR China c Research Centre for Coastal Geology,China Geological Survey,Qingdao 266071,PR China d College of Marine Geosciences,Ocean University of Qingdao,Qingdao 266003,PR China

The rock magnetic properties of surface sediments from the fine-grained depositional area on the outer shelf of the East China Sea,an area surrounded by sands,were investigated with a view to providing information on the sediment provenance.Multiple magnetic parameters such as magnetic susceptibility,anhysteretic remanent magnetization,saturation remanent magnetization(SIRM),coercivities of SIRM,and S ratios(relative abundance of low-coercivity magnetic minerals) were measured for all 179 surface samples,and partial representative samples were examined for their magnetic hysteresis parameters,temperature dependence of magnetic susceptibility and X-ray diffraction spectra.Our research indicates that the magnetic mineralogy is dominated by magnetite with a small amount of hematite and is primarily of a pseudo-single-domain to multidomain nature with a detrital origin.The magnetic concentration in the study area generally decreases to the east or southeast accompanied by magnetic particle fining to the east or northeast.The geographic pattern of magnetic properties is most reasonably explained by a major source of sediment jointly from the erosion of the old Huanghe River deposit and the discharge of the Changjiang River.The rock magnetic data facilitate understanding of the transport mechanism of fine-grained sediments in the outer shelf of the East China Sea.

关键词： marine sediments environmental magnetism sediment sources East China Sea

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USING ENVIRONMENTAL RADIONUCLIDES TO TRACE sediment MOBILISATION AND DELIVERY IN RIVER BASINS AS AN AID TO CATCHMENT MANAGEMENT

USING ENVIRONMENTAL RADIONUCLIDES TO TRACE SEDIMENT MOBILISA...

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第九次河流泥沙国际学术大会

作者： Des E.WALLING Department of Geography University of Exeter Exeter EX4 4RJ UK.

＜正＞Although sediment problems have long been recognised in those areas of the world with high rates of soil loss and high specific sediment yields, recent years have seen a growing recognition of the wider significance of fine sediment as an environmental problem. This has resulted in a growing need to incorporate sediment control strategies into catchment management programmes. The design of effective sediment control strategies is, however, heavily dependent upon a sound understanding and knowledge of sediment mobilisation and delivery within the catchment system and thus the overall sediment budget. Traditional monitoring techniques are generally unable to provide information on the internal functioning of the sediment budget. Against this background, there is a need for new approaches to data collection and tracing techniques are being increasingly used. Environmental radionuclides provide a particularly useful tool for tracing sediment mobilisation and delivery and this paper provides further information on the basis for their use and on their potential applications. Selected examples of their application to documenting rates of soil loss and sediment delivery from cultivated fields, sediment source tracing, and documenting rates of floodplain sedimentation and longer-term changes in suspended sediment properties are provided.

关键词： Environmental radionuclides Caesium-137 Lead-210 Beryllium-7 Erosion Deposition sediment sources Floodplain sedimentation sediment-associated nutrients Phosphorus

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