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Journal of Environmental Sciences 2009年第12期21卷 1625-1631页

作者： HUI Yamei ZHENG Minghui LIU Zhengtao GAO Lirong State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China China Research Academy of Environmental Sciences Beijing 100012 China

Surface sediment samples collected from twenty-one sites of yellow river estuary and Yangtze river estuary were determined for sixteen priority polycyclic aromatic hydrocarbons （PAHs） by isotope dilution GC-MS method. The total PAH contents varied from 10.8 to 252 ng/g in yellow river estuary sediment, and from 84.6 to 620 ng/g in Yangtze river estuary sediment. The mean total PAH content of Yangtze river estuary was approximately twofold higher than that of yellow river estuary. The main reasons for the difference may be the rapid industrial development and high population along Yangtze river and high silt content of yellow river estuary. The evaluation of PAH sources suggested that PAHs in two estuaries sediments estuaries were derived primarily from combustion sources, but minor amounts of PAHs were derived from petroleum source in yellow river estuary. PAHs may be primary introduced to yellow river estuary via dry/wet deposition, wastewater effluents, and accidental oil spills, and Yangtze river estuary is more prone to be affected by wastewater discharge.

关键词： PAHs sediment yellow river estuary Yangtze river estuary

Nitrogen cycle of a typical Suaeda salsa marsh ecosystem in the yellow river estuary

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Journal of Environmental Sciences 2011年第6期23卷 958-967页

作者： Xiaojie Mou Zhigao Sun Lingling Wang Chuanyuan Wang Key laboratory of Coastal Environment Processes CAS Shandong Provincial Key Laboratory of Coastal Zone Environmental Processes Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Yantai 264003 China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China Graduate University of Chinese Academy of Sciences Beijing 100039 China

The nitrogen（N） biological cycle of the Suaeda salsa marsh ecosystem in the yellow river estuary was studied during 2008 to *** showed that soil N had significant seasonal fluctuations and vertical *** N/P ratio（15.73±1.77） of *** was less than 16,indicating that plant growth was limited by both N and *** N absorption coefficient of *** was very low（0.007）,while the N utilization and cycle coefficients were high（0.824 and 0.331,respectively）.The N turnover among compartments of *** marsh showed that N uptake from aboveground parts and roots were 2.539 and 0.622 g/m2,*** N translocation from aboveground parts to roots and from roots to soil were 2.042 and 0.076 g/m2,*** N translocation from aboveground living bodies to litter was 0.497 g/m2,the annual N return from litter to soil was far less than 0.368 g/m2,and the net N mineralization in topsoil during the growing season was 0.033 g/m2.N was an important limiting factor in *** marsh,and the ecosystem was classified as unstable and *** was seemingly well adapted to the low-nutrient status and vulnerable habitat,and the nutrient enrichment due to N import from the yellow river estuary would be a potential threat to the *** *** nutrient loading might favor invasive species and induce severe long-term degradation of the ecosystem if human intervention measures were not *** N quantitative relationships determined in our study might provide a scientific basis for the establishment of effective measures.

关键词： compartment model nitrogen biological cycle Suaeda salsa yellow river estuary

Potential Effects of Episodic Deposition on Nutrients and Heavy Metals in Decomposing Litters of Suaeda glauca in Salt Marsh of the yellow river estuary, China

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Chinese Geographical Science 2020年第3期30卷 466-482页

作者： CHEN Bingbing SUN Zhigao Key Laboratory of Humid Subtropical Eco-geographical Process(Fujian Normal University) Ministry of EducationFuzhou 350007China Institute of Geography Fujian Normal UniversityFuzhou 350007China Fujian Provincial Key Laboratory for Subtropical Resources and Environment Fujian Normal UniversityFuzhou 350007China

Episodic deposition has been recognized as a major factor affecting the decomposition rate of detrital material in salt marshes. In this paper, three one-off burial treatments, no burial treatment(0 cm, NBT), current burial treatment(10 cm, CBT) and strong burial treatment(20 cm, SBT), were designed in intertidal zone of the yellow river estuary to determine the potential influences of episodic deposition on nutrient(C, N) and heavy metal(Pb, Cr, Cu, Zn, Ni, Mn, Cd, V and Co) variations in decomposing litters of Suaeda glauca. Results showed that although various burial treatments showed no statistical difference in decomposition rate of S. glauca, the values generally followed the sequence of CBT(0.002 403/d) > SBT(0.002 195/d) > NBT(0.002 060/d). The nutrients and heavy metals in decomposing litters of the three burial treatments exhibited different variations except for N, Cu, Cr, Ni and Co. Except for Mn, no significant differences in C, N, Pb, Cr, Cu, Zn, Ni, V and Co concentrations occurred among the three treatments(P > 0.05). With increasing burial depth, Cr and Cd levels generally increased while Cu, Ni and Mn concentrations decreased. Although episodic deposition was generally favorable for C and N release from S. glauca, its influence on release was insignificant. In the three burial treatments, Pb, Cr, Zn, Ni, Mn, V and Co stocks in S. glauca generally evidenced the export of metals from litter to environment, and, with increasing burial depth, the export amounts increased greatly. The S. glauca were particular efficient in binding Cd and releasing Pb, Cr, Zn, Ni, Mn, V and Co, and, with increasing burial depth, stocks of Cu in decomposing litters generally shifted from release to accumulation. The experiment indicated that the potential eco-toxic risk of Pb, Cr, Zn, Ni, Mn, V and Co exposure would be serious as the strong burial episodes occurred in S. glauca marsh.

关键词： decomposition nutrient and metal episodic deposition Suaeda glauca yellow river estuary

Influence of bathymetry evolution on position of tidal shear front and hydrodynamic characteristics around the yellow river estuary

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Frontiers of Earth Science 2012年第4期6卷 405-419页

作者： Yucen LU Yongming SHEN State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116023 China

A three dimensional numerical model based on the hydrodynamic module of finite-volume coastal ocean （FVCOM） was established for the yellow river estuary. The model has been calibrated by observed data and proved to be suitable to reflect the hydrodynamic force in the research area. We employed the model to simulate the tidal shear front off the yellow river estuary and analyzed the formation, spread and duration of two different types of shear front. To examine the effect ofbathymetry evolution on the position of tidal shear front, subaqueous bathymetry of the yellow river estuary was changed according to the changing patterns obtained from the past few years. Tidal shear front was modeled on both the original and the changed bathymetry. The results show that the position of shear front moved from a shallow to a deep area due to the deposition of bathymetry. The influence of bathymetry evolution on hydrodynamic characteristics including the distribution of salinity and the movement of particles was studied. We found the dispersion areas of low salinity became larger after changing bathymetry and the particles on the surface, middle and bottom layer are able to move further both north and west of Laizhou Bay on the changed bathymetry.

关键词： yellow river estuary shear front hydrody- namic force bathymetry evolution salinity

Remote Sensing Retrieval of Surface Suspended Sediment Concentration in the yellow river estuary

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Chinese Geographical Science 2017年第6期27卷 934-947页

作者： ZHAN Chao YU Junbao WANG Qing LI Yunzhao ZHOU Di XING Qinghui CHU Xiaojing Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Yantai 264003 China The Institute of Coastal Ecology Ludong University Yantai 264025 China University of Chinese Academy of Sciences Beijing 100049 China

Accurate assessment of surface suspended sediment concentration （SSSC） in estuary is essential to address several important issues： erosion, water pollution, human health risks, etc. In this study, an empirical cubic retrieval model was developed for the retrieval of SSSC from yellow river estuary. Based on sediments and seawater collected from the yellow river and southeastern Laizhou Bay, SSSC conditions were reproduced in the laboratory at increasing concentrations within a range common to field observations. Continu- ous spectrum measurements of the various SSSCs ranging from 1 to 5700 mg/1 were carried out using an AvaField-3 spectrometer. The results indicated the good correlation between water SSSC and spectral reflectance （Rrs） was obtained in the spectral range of 726-900 nm. At SSSC greater than 2700 mg/L, the 740-900 nm spectral range was less susceptible to the effects of spectral reflectance saturation and more suitable for retrieval of high sediment concentrations. The best correlations were obtained for the reflectance ratio of 820 nm to 490 nm. Informed by the correlation between Rrs and SSSC, a retrieval model was developed （R2 = 0.992）. The novel cubic model, which used the ratio of a near-infrared （NIR） band （740-900 nm） to a visible band （400-600 nm） as factors, provided robust quantifica- tion of high SSSC water samples. Two high SSSC centers, with an order of 103 mg/1, were found in the inversion results around the abandoned Diaokou river mouth, the present yellow river mouth to the abandoned Qingshuigou river mouth. There was little sedi- ment exchange between the two high SSSC centers due to the directions of the residual currents and vertical mixing.

关键词： surface suspended sediment concentration (SSSC) water spectral reflectance cubic model quantitative remote sensinginversion yellow river estuary

The Derivation of Nutrient Criteria for the Adjacent Waters of yellow river estuary in China

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Journal of Ocean University of China 2022年第5期21卷 1227-1236页

作者： LOU Qi ZHANG Xueqing ZHAO Bei CAO Jing LI Zhengyan College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China North China Sea Environmental Monitoring Center State Oceanic AdministrationQingdao 266033China Key Laboratory of Marine Environmental Science and Ecology Ministry of EducationQingdao 266100China

Ecological protection and high-quality development of the yellow river basin are becoming part of the national strategy in recent *** yellow river estuary has been seriously affected by human ***,it has been severely polluted by the nitrogen and phosphorus from land sources,which have caused serious eutrophication and harmful algal *** criteria,however,was not developed for the yellow river estuary,which hindered nutrient management measures and eutrophication risk assessment in this key ecological function zone of *** on field data during 2004-2019,we adopted the frequency distribution method,correlation analysis,Linear Regression Model(LRM),Classification and Regression Tree(CART)and Nonparametric Changepoint Analysis(nCPA)methods to establish the nutrient criteria for the adjacent waters of yellow river *** water quality criteria of dissolved inorganic nitrogen(DIN)and soluble reactive phosphorus(SRP)are recommended as 244.0μg L^(−1) and 22.4μg L^(−1),*** is hoped that the results will provide scientific basis for the formulation of nutrient standards in this important estuary of China.

关键词： water quality criteria nutrient yellow river estuary frequency distribution classification and regression tree eutro-phication

Experimental Research on the Marine Hydrodynamic Action on the Consolidation Process of the Sediments in the yellow river estuary

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China Ocean Engineering 2011年第1期25卷 149-157页

作者：杨秀娟贾永刚李相然单红仙 Architecture Engineering Department Wenjing College of Yantai University Environmental Science and Engineering College Ocean University of China

Based on the in-situ measurements, the impact of the marine hydrodynamics, such as wave and tide, in the rapidly deposited sediments consolidation process was studied. In the tide flat of Diaokou delta-lobe, one 2 m × 1 m × 1 m test pit was excavated. The seabed soils were dug and dehydrated, and then the powder of the soil was mixed with seawater to be fluid sediments. And an iron plate covered part of the test pit to cut off the effect of the marine hydrodynamics, By field-testing methods, like static cone penetration test （SPT） and vane shear test （VST）, the variation of strength is measured as a function of time, and the marine hydrodynamics impact on the consolidation process of the sediments in the yellow river estuary was studied. It is shown that the self-consolidated sediments＇ strength linearly increases with the depth. In the consolidation process, in the initial, marine hydrodynamics play a decisive role, about 1.5 times as much as self-consolidated in raising the strength of the sea-bed soils, and with the extension of the depth the role of the hydrodynamics is reduced. In the continuation of the consolidation process, the trend of the surface sediments increased-strength gradually slows down under the water dynamics, while the sediments below 50 cm are in opposite ways. As a result, the rapidly deposited silt presents a nonuniform consolidation state, and the crust gradually forms. The results have been referenced in studying the role of the hydrodynamics in the soil consolidation process.

关键词： yellow river estuary seabed soil marine hydrodynamics conolidation process

Potential Impacts of Exogenous Nitrogen Enrichment on Distribution and Transfer of Nitrogen in Plant-Soil System of Suaeda salsa Marsh in the yellow river estuary, China

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Journal of Ocean University of China 2023年第1期22卷 258-270页

作者： HU Xingyun SUN Zhigao YU Linying CHEN Bingbing Fujian Provincial Key Laboratory for Subtropical Resources and Environment Fujian Normal UniversityFuzhou 350007China Key Laboratory of Humid Subtropical Eco-Geographical Process(Fujian Normal University) Ministry of EducationFuzhou 350007China Institute of Geography Fujian Normal UniversityFuzhou 350007China

To determine the potential impacts of exogenous nitrogen(N)enrichment on distribution and transfer of N in Suaeda salsa marsh in the yellow river estuary,the variations of N in plant-soil system during the growing season were investigated by field N addition *** experiment included four treatments:NN(no N input treatment,0gNm^(−2) yr^(−1)),LN(low N input treatment,3.0 gNm^(−2) yr^(−1)),MN(medium N input treatment,6 gNm^(−2) yr^(−1))and HN(high N input treatment,12 gNm^(−2) yr^(−1)).Results showed that N additions generally increased the contents of total nitrogen(TN),ammonia nitrogen(NH_(4)^(+)-N)and nitrate nitrogen(NO_(3)^(−)-N)in different soil layers and the increasing trend was particularly evident in *** with the NN treatment,the average contents of TN in topsoil in the LN,MN and HN treatments during the growing season increased by 10.85%,30.14%and 43.98%,the mean contents of NH_(4)^(+)-N increased by 8.56%,6.96%and 14.34%,and the average contents of NO_(3)^(−)-N increased by 35.73%,45.99%and 46.66%,*** exogenous N import did not alter the temporal variation patterns of TN contents in organs,the N transfer and accumulation differed among tissues in different *** increasing N import,both the N stocks in soil and plant showed increasing trend and the values in N addition treatments increased by 9.43%–38.22%and 13.40%–62.20%,*** was worth noting that,compared with other treatments,the *** in the MN treatments was very likely to have special response to N enrichment since not only the period of peak growth was prolonged by about 20 days but also the maximum of TN content in leaves was advanced by approximately one *** paper found that,as N loading reached MN level in future,the growth rhythm of *** and the accumulation and transference of N in its tissues would be altered significantly,which might generate great impact on the stability and health of *** marsh ecosystem.

关键词： nitrogen import nitrogen transfer plant-soil system Suaeda salsa yellow river estuary

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Variation in reach-averaged bankfull discharge in the yellow river estuary in recent years

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Frontiers of Earth Science 2021年第3期15卷 606-619页

作者： Zhuoyuan YANG Junqiang XIA Meirong ZHOU Shanshan DENG Zenghui WANG Zhiwei LI State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China

The yellow river estuary(YRE)alternatively experienced channel aggradation and degradation during the period *** study the variation in flood discharge capacity during the process of river bed evolution,bankfull characteristic parameters were investigated on the basis of measured hydrological data and surveyed cross-sectional profiles,which was crucial for comprehending the processes and the key factors to cause these rapid changes.A reach-averaged method was presented in this study in order to calculate the characteristic bankfull parameters in the YRE,and this method integrated the geometric mean using the logarithmic transformation with a weighted mean based on the distance between the two successive *** reach-averaged bankfull parameters in the tail reach of the yellow river estuary(the Lijin-Xihekou reach)during the period 1990-2016 were then *** results indicated that the adoption of a concept of reach-averaged bankfull discharge was much more representative than the cross-sectional bankfull discharge,and the results also indicated that bankfull discharges decreased during the process of channel aggradation,and increased during the process of channel ***,an empirical formula and a delayed response function were established between the reach-averaged bankfull discharge and the previous 4-year average fluvial erosion intensity during flood seasons,and both of them were adopted to reproduce the reach-averaged bankfull discharges,and calculated results showed high correlations(R^(2)>0.8)of these two methods.

关键词： channel adjustments reach-averaged bankfull discharge empirical relation delayed response equation yellow river estuary

The Effects of Estuarine Processes on the Fluxes of Inorganic and Organic Carbon in the yellow river estuary

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Journal of Ocean University of China 2009年第4期8卷 352-358页

作者： GU Dianjun ZHANG LongJun JIANG Liqing College of Environmnetal Science and Engineering Ocean University of China Qingdao 266100 P. R. China National Oceanographic and Atmospheric Administration Climate Program Office Maryland 20910 USA

riverine carbon flux is an important component of the global carbon cycle. The spatial and temporal variations of organic and inorganic carbon were examined during both dry and wet seasons in the yellow river estuary. Concentrations of dissolved organic carbon （DOC） and dissolved inorganic carbon （DIC） in the yellow river during dry seasons were higher than those during wet seasons. The effective concentrations of DOC （CDOC＊） were higher than the observed DOC at zero salinity. This input of DOC in the yellow river estuary was due to sediment desorption processes in low salinity regions. In contrast to DOC, the effective concen- trations of DIC were 10% lower than the DIC measured at freshwater end, and the loss of DIC was caused by CaCO3 precipitation in low salinity region, Particulate organic carbon （POC） and particulate inorganic carbon （PIC） contents of the particles stabilized to constant values （0.5%：t：0.05% and 1.8%--0.2%, respectively） within the turbidity maximum zone （TMZ） and showed no noticeable seasonal variations. A rapid drop of PIC and rise of POC occurred simultaneously outside the TMZ due to an intense dilution of riv- erine inorganic-rich particles being transported into a pool of aquatic organic-poor particles outside the TMZ. Annually, the yellow river transported 6.95× 10^5 t of DIC, 0.64× 10^5 t of DOC, 78.58× 10^5 t of PIC and 2.29× 10^5 t of POC to the sea.

关键词： particulate organic carbon particulate inorganic carbon dissolved organic carbon dissolved inorganic carbon yellow river estuary