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Chen X, Liang L, Fu S, Bao X, Gu S, Jiao Y, Hu F, Rahman A, Li Q. Distribution characteristics of reactive silicon in six water bodies in the Yangtze River Basin in China. ENVIRONMENTAL RESEARCH 2024; 249:118424. [PMID: 38325775 DOI: 10.1016/j.envres.2024.118424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 01/29/2024] [Accepted: 02/02/2024] [Indexed: 02/09/2024]
Abstract
Terrestrial silicon (Si) from biogeochemically weathered rocks and soils into oceans must pass through several water bodies, resulting in some Si immobilized. Hence, the knowledge on Si distribution characteristics in different water bodies at a basin scale is helpful to understand Si immobilization. A total of 65 surface sediments and corresponding overlying water samples were sampled from six water bodies (Dianchi Lake, DL; Dadu River, DR; Tuojiang River, TR; Honghu Lake, HL; Donghu Lake, DhL; Taihu Lake, TL) in the Yangtze River Basin of China, total dissolved Si (TDSi) in overlying water and exchangeable Si (Ex-Si), active non-biogenic Si (NBSi), and total acid dissolved Si (TADSi) in sediments were analyzed. Water chemical parameters (pH, EC, and TDP) and sediment components (LOI, TN, TP, and TADFe) showed that the water environment characteristics of six water bodies differed. TDSi differed among regions and between lakes and rivers, significantly higher in water bodies in the upper reaches and rivers than the middle or lower reaches and lakes (p < 0.05), respectively. Ex-Si in sediments in the upper reaches was significantly higher than in the middle or lower reaches (p < 0.05), except for DhL, whose Ex-Si was the highest. Mean TADSi and active NBSi were significantly higher in lakes than rivers (p < 0.05). Oxidation of sediments significantly increased TDSi in overlying water and active NBSi in sediments (p < 0.01). Si forms in six water bodies significantly depended on components of the sediments (e.g. active Ca2+, Mg2+, Fe, and Al3+) and water chemical parameters (p < 0.05). Our results suggest that immobilization of Si in water bodies in the Yangtze River Basin depends on the types of water bodies and sediments, lakes and Fe-Al dominated sediments have a high potential to immobilize Si, but anthropogenic interference should not be ignored.
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Affiliation(s)
- Xuemei Chen
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lanwei Liang
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; School of Environment Studies, China University of Geosciences, Wuhan, Hubei, 430074, China
| | - Songjie Fu
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; School of Environment Studies, China University of Geosciences, Wuhan, Hubei, 430074, China
| | - Xu Bao
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Sen Gu
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Yang Jiao
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Fang Hu
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; School of Environment Studies, China University of Geosciences, Wuhan, Hubei, 430074, China
| | - Abdur Rahman
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qingman Li
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
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Arce-Rodríguez A, Libby E, Castellón E, Avendaño R, Cambronero JC, Vargas M, Pieper DH, Bertilsson S, Chavarría M, Puente-Sánchez F. Out of the blue: the independent activity of sulfur-oxidizers and diatoms mediate the sudden color shift of a tropical river. ENVIRONMENTAL MICROBIOME 2023; 18:6. [PMID: 36658604 PMCID: PMC9854191 DOI: 10.1186/s40793-023-00464-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 01/10/2023] [Indexed: 06/17/2023]
Abstract
BACKGROUND Río Celeste ("Sky-Blue River") is a river located in the Tenorio National Park (Costa Rica) that has become an important hotspot for eco-tourism due to its striking sky-blue color. A previous study indicated that this color is not caused by dissolved chemical species, but by formation of light-scattering aluminosilicate particles at the mixing point of two colorless streams, the acidic Quebrada Agria and the neutral Río Buenavista. RESULTS We now present microbiological information on Río Celeste and its two tributaries, as well as a more detailed characterization of the particles that occur at the mixing point. Our results overturn the previous belief that the light scattering particles are formed by the aggregation of smaller particles coming from Río Buenavista, and rather point to chemical formation of hydroxyaluminosilicate colloids when Quebrada Agria is partially neutralized by Río Buenavista, which also contributes silica to the reaction. The process is mediated by the activities of different microorganisms in both streams. In Quebrada Agria, sulfur-oxidizing bacteria generate an acidic environment, which in turn cause dissolution and mobilization of aluminum and other metals. In Río Buenavista, the growth of diatoms transforms dissolved silicon into colloidal biogenic forms which may facilitate particle precipitation. CONCLUSIONS We show how the sky-blue color of Río Celeste arises from the tight interaction between chemical and biological processes, in what constitutes a textbook example of emergent behavior in environmental microbiology.
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Affiliation(s)
- Alejandro Arce-Rodríguez
- Institute of Microbiology, Technical University of Braunschweig, 38106, Brunswick, Germany
- Microbial Interactions and Processes Research Group, Helmholtz Centre for Infection Research, 38124, Brunswick, Germany
| | - Eduardo Libby
- Escuela de Química, Universidad de Costa Rica, San José, 11501-2060, Costa Rica
| | - Erick Castellón
- Escuela de Química, Universidad de Costa Rica, San José, 11501-2060, Costa Rica
- Centro de Investigación en Ciencia e Ingeniería de Materiales (CICIMA), Universidad de Costa Rica, San José, 11501-2060, Costa Rica
| | - Roberto Avendaño
- Centro Nacional de Innovaciones Biotecnológicas (CENIBiot), CeNAT-CONARE, San José, 1174-1200, Costa Rica
| | - Juan Carlos Cambronero
- Centro de Investigaciones en Productos Naturales (CIPRONA), Universidad de Costa Rica, San José, 11501-2060, Costa Rica
| | - Maribel Vargas
- Centro de Investigaciones en Estructuras Microscópicas (CIEMic), Universidad de Costa Rica, San José, 11501-2060, Costa Rica
| | - Dietmar H Pieper
- Microbial Interactions and Processes Research Group, Helmholtz Centre for Infection Research, 38124, Brunswick, Germany
| | - Stefan Bertilsson
- Deparment of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Lennart Hjelms Väg 9, 756 51, Uppsala, Sweden
| | - Max Chavarría
- Escuela de Química, Universidad de Costa Rica, San José, 11501-2060, Costa Rica
- Centro Nacional de Innovaciones Biotecnológicas (CENIBiot), CeNAT-CONARE, San José, 1174-1200, Costa Rica
- Centro de Investigaciones en Productos Naturales (CIPRONA), Universidad de Costa Rica, San José, 11501-2060, Costa Rica
| | - Fernando Puente-Sánchez
- Deparment of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Lennart Hjelms Väg 9, 756 51, Uppsala, Sweden.
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Huang L, Parsons CT, Slowinski S, Van Cappellen P. Amorphous silica dissolution kinetics in freshwater environments: Effects of Fe 2+ and other solution compositional controls. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 851:158239. [PMID: 36007651 DOI: 10.1016/j.scitotenv.2022.158239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/24/2022] [Accepted: 08/19/2022] [Indexed: 06/15/2023]
Abstract
The availability of dissolved silicon (DSi) exerts an important control on phytoplankton communities in freshwater environments: DSi limitation can shift species dominance to non-siliceous algae and increase the likelihood of harmful algal blooms. The availability of DSi in the water column in turn depends on the dissolution kinetics of amorphous silica (ASi), including diatoms frustules and phytoliths. Here, batch dissolution experiments conducted with diatom frustules from three diatom species and synthetic Aerosil OX 50 confirmed the previously reported non-linear dependence of ASi dissolution rate on the degree of undersaturation of the aqueous solution. At least two first-order dissolution rate constants are therefore required to describe the dissolution kinetics at high (typically, ≥0.55) and low (typically, <0.55) degrees of undersaturation. Our results further showed aqueous ferrous ion (Fe2+), which is ubiquitous in anoxic waters, strongly inhibited ASi dissolution. The inhibition is attributed to the preferential binding of Fe2+ to Q2 groups (i.e., surface silicate groups bonded to the silica lattice via two bridging oxygen) which stabilizes the silica surface. However, further increasing the aqueous Fe2+ concentration likely catalyzes the detachment of Q3 groups (i.e., silicate groups bonded to the silica lattice via three bridging oxygen) from the surface. Overall, our study illustrates the manyfold effects the aqueous solution composition, notably the inhibition effect of Fe2+ under anoxic conditions, has on ASi dissolution. The results help to explain the controversial redox dependence of DSi internal loading from sediments, which is vital to quantitatively understanding silicon (Si) cycling in freshwater systems.
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Affiliation(s)
- Lu Huang
- Ecohydrology Research Group, Department of Earth and Environmental Sciences and The Water Institute, University of Waterloo, Waterloo, ON N2L 3G1, Canada; National Key Laboratory of Water Environmental Simulation and Pollution Control, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, No. 18 Ruihe Road, Guangzhou 510530, China.
| | - Chris T Parsons
- Ecohydrology Research Group, Department of Earth and Environmental Sciences and The Water Institute, University of Waterloo, Waterloo, ON N2L 3G1, Canada; Watershed Hydrology and Ecology Research Division, Environment and Climate Change Canada, 867 Lakeshore Road, Burlington, Ontario L7S 1A1, Canada
| | - Stephanie Slowinski
- Ecohydrology Research Group, Department of Earth and Environmental Sciences and The Water Institute, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Philippe Van Cappellen
- Ecohydrology Research Group, Department of Earth and Environmental Sciences and The Water Institute, University of Waterloo, Waterloo, ON N2L 3G1, Canada
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Herath IK, Wu S, Ma M, Ping H. Reservoir NO 3- pollution and chemical weathering: by dual isotopes of δ 15N-NO 3-, δ 18O-NO 3- and geochemical constraints. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2022; 44:4381-4402. [PMID: 35079909 DOI: 10.1007/s10653-021-01195-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 12/23/2021] [Indexed: 06/14/2023]
Abstract
Reservoir dams alter the nutrient composition and biogeochemical cycle. Thus, dual isotopes of δ18O-NO3- and δ15N-NO-3 and geochemical signatures were employed to study the NO3- pollution and chemical weathering in the Three Gorges Reservoir (TGR), China. This study found that the TGR dam alters the δ15N-NO3- composition and is enriched in the recharge period. Values of δ15N-NO3- varied from 4.5 to 12.9‰ with an average of 9.8‰ in the recharge period, while discharge period δ15N-NO3- ranged from 3.2 to 12.5‰, with an average of 9.3‰. δ18O-NO3- varies (1.2-11.3‰) with an average of 6.5‰ and (2.4-12.4‰) with an average of 7.5‰, in the recharge and discharge periods, respectively. Stable isotopic values sharply decreased from upstream to downstream, indicating the damming effects. δ18O-NO3- and δ15N NO3- confirm that sewage effluents, nitrification of soil organic material, and NH4+ fertilizers were the primary sources of NO3- in the reservoir. Carbonate weathering mainly provides ions to the reservoir. HCO3- + SO42- and Ca2+ + Mg2+ represent 90% of major ions in the TGR. Downstream sampling sites showed low solute concentration during the recharge period, indicating the dam effect on solute concentration. Ca-Mg-Cl-, Ca-HCO3- and Ca-Cl- were the main water types in the TGR. The average percentage of solutes contribution revealed the carbonate weathering, evaporites dissolution, silicate weathering, and atmospheric input were 51.9%, 41%, 7.8%, and 1.7% for the recharge period. In contrast, the discharge period contributed 66.4%, 29.2%, 10%, and 4.3%, respectively. TGR water is moderately suitable for irrigation, and hardness is high in drinking water. This study provides new insight into the dual isotopic approach and geochemical signatures to interpret the NO3- cycle and chemical weathering process under dam effects in the TGR. However, this isotopic application has some limitations in source identification, isotope fractionation, and transformation mechanisms of nitrate. Thus, further studies need to be done on these topics for a better undestanding.
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Affiliation(s)
- Imali Kaushalya Herath
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, China.
| | - Shengjun Wu
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, China.
| | - Maohua Ma
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, China
| | - Huang Ping
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, China
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Ran X, Wu W, Song Z, Wang H, Chen H, Yao Q, Xin M, Liu P, Yu Z. Decadal change in dissolved silicate concentration and flux in the Changjiang (Yangtze) River. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 839:156266. [PMID: 35644380 DOI: 10.1016/j.scitotenv.2022.156266] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 05/22/2022] [Accepted: 05/23/2022] [Indexed: 06/15/2023]
Abstract
Silicon (Si) plays an essential role in the biogeochemistry of rivers. This study explored how damming, eutrophication and climate change alters the abundance and flux of DSi in the Changjiang (Yangtze) River based on long-term observations. The results showed that Three Gorges Reservoir (TGR) could enhance DSi transfer only during low-flow time period, and a downstream DSi retention effect by the TGR was found between the Yichang and Jianli stations in the Changjiang River. This resulted in a DSi loss during March and April in the mainstream from Three Gorges Dam (TGD) to Jianli but a DSi addition during July and October along the main channel of the Changjiang River. Long-term data showed a sharp decrease in DSi abundance at the Cuntan, Hankou and Datong stations between the 1960s and 1980s, but a slight increase in DSi between the 1990s and 2010s at these stations. The decrease in DSi during the 1960s -1980s was primarily the result of a decrease trend of silicate weathering, while a slight DSi increase compared to the temperature/DSi relation after the 1990s was largely due to increased DSi retention in the basin by damming and eutrophication. Eutrophication and damming increase DSi trapping in both the river channel and reservoir systems in the low-flow period and thus enhance the nutrient distortion in the coastal ocean.
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Affiliation(s)
- Xiangbin Ran
- Research Center for Marine Ecology, First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, PR China; Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, PR China; Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China.
| | - Wentao Wu
- Research Center for Marine Ecology, First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, PR China; Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, PR China
| | - Zhaoliang Song
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Hao Wang
- Research Center for Marine Ecology, First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, PR China; Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, PR China
| | - Hongtao Chen
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, PR China
| | - Qingzhen Yao
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, PR China
| | - Ming Xin
- Research Center for Marine Ecology, First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, PR China
| | - Pengxia Liu
- Ecology and Environment Monitoring and Scientific Research Center of Taihu Basin, East China Sea Ecology and Environment Supervision Authority, Ministry of Ecology and Environment, Shanghai 200120, China
| | - Zhigang Yu
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, PR China
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Guo Y, Deng B. Seasonal variation of heavy metals in suspended sediments downstream the Three Gorges Dam in the Yangtze River. ENVIRONMENTAL MONITORING AND ASSESSMENT 2022; 194:660. [PMID: 35945328 DOI: 10.1007/s10661-022-10337-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
High sediment flux in large rivers provide sufficient dilution to the heavy metals' concentration. However, sediment starvation caused by hydrological engineering in recent decades has been reported worldwide. Thus, a study is necessary on the influences of recent declining sediment flux on heavy metal pollution change in the suspended sediments. In this study, heavy metal concentrations and speciation (Cd, Pb, Zn, Cu, Co, Ni, and Cr) in suspended sediments were investigated downstream the Three Gorges Dam (TGD) during dry and flood seasons. Substantial changes of Pb, Zn, Cd, and Cu along the river channel were found which were constrained by the dilution efficiency of suspended sediment during the dry season. High proportion of labile fraction revealed anthropogenic sources of heavy metal. Moreover, the historical trend of metal content illustrated TGD construction together with anthropogenic influx both contribute to the increasing environmental risk in the Yangtze River basin.
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Affiliation(s)
- Yutong Guo
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, 200241, China
| | - Bing Deng
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, 200241, China.
- Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, 519080, China.
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Dan SF, Li S, Yang B, Cui D, Ning Z, Huang H, Zhou J, Yang J. Influence of sedimentary organic matter sources on the distribution characteristics and preservation status of organic carbon, nitrogen, phosphorus, and biogenic silica in the Daya Bay, northern South China Sea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 783:146899. [PMID: 33865127 DOI: 10.1016/j.scitotenv.2021.146899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 03/28/2021] [Accepted: 03/29/2021] [Indexed: 06/12/2023]
Abstract
Surface sediment samples were collected from Daya Bay in October 2018, and analyzed for total organic carbon (OC), total nitrogen (TN) and their stable isotopes (δ13C and δ15N), total phosphorus (TP), biogenic silica (BSi), sediment textures and specific surface area (SSA). The primary objective was to evaluate the influence of mariculture/aquaculture on the distribution characteristics of organic matter (OM), and preservation status of OC, TN, TP, and BSi in sediments. The average δ13C and δ15N values, and OC/TN ratios were -21.27‰, 6.74‰, and 8.90, respectively. Monte Carlo simulation results revealed that mariculture/aquaculture biodeposits accounted for >40% of the buried OM at sites where the breeding rafts and cages are located, whereas marine OM increased gradually to the open sea. Terrestrial OM was generally low accounting for 17% by average. The contents and distribution characteristics of biogenic elements were more influenced by mariculture/aquaculture and primary productivity than sediment textures. Lower OC/SSA (0.3-1.2 mg OC/m2), TN/SSA (~0.05-0.18 mg TN/m2), and TP/SSA (0.02-0.04 mg TP/m2) loadings indicated that increased sequestration of labile OM in a coastal bay could contribute to significant degradation of recalcitrant OM in sediments with significant loss of P relative to OC. Nitrogen contamination in surface sediments was due to increased injection of aquaculture biodeposits, and may pose a detrimental effect on the ecological sustainability of the bay. Higher BSi/SSA loadings (0.9-1.7 mg BSi/m2) revealed that BSi was more preserved, and that BSi-based proxy could be used for paleo-productivity studies. However, such preservation may induce adverse dissolved silicate limitation in a bay perturbed by eutrophication. Fine-grained sediments (clay and silt) accounted for >77% of the sediment texture types with higher SSA, and while controlling the contents of biogenic elements under given depositional conditions were not the main determining factors of OC, TN, TP, and BSi preservation.
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Affiliation(s)
- Solomon Felix Dan
- Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf, Beibu Gulf University, Qinzhou 535011, China
| | - Shengyong Li
- South China Sea Environmental Monitoring Center, State Oceanic Administration, Guangzhou 510300, China
| | - Bin Yang
- Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf, Beibu Gulf University, Qinzhou 535011, China.
| | - Dongyang Cui
- Key Laboratory of Urban Land Resources Monitoring and Simulation, Ministry of Natural Resources, Shenzhen 518000, China
| | - Zhiming Ning
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University, Nanning 530004, China
| | - Haifang Huang
- Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf, Beibu Gulf University, Qinzhou 535011, China
| | - Jiaodi Zhou
- Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf, Beibu Gulf University, Qinzhou 535011, China
| | - Jian Yang
- Research Center for Coastal Environment Engineering Technology of Shandong Province, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
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Xu C, Yang B, Dan SF, Zhang D, Liao R, Lu D, Li R, Ning Z, Peng S. Spatiotemporal variations of biogenic elements and sources of sedimentary organic matter in the largest oyster mariculture bay (Maowei Sea), Southwest China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 730:139056. [PMID: 32388378 DOI: 10.1016/j.scitotenv.2020.139056] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Revised: 04/17/2020] [Accepted: 04/26/2020] [Indexed: 06/11/2023]
Abstract
China is the largest mariculture producer in the world, but detailed information on the spatiotemporal variations of biogenic elements and sources of sedimentary organic matter (SOM) via mariculture is limited. The primary objective of this study was to assess the influence of mariculture on the origin of SOM in relation with biogenic elements and geochemical paramaters due to the importance of SOM as a potential source of nutrients and energy in coastal marine environments. Surface sediments from the Maowei Sea were collected in August (summer) and December (winter), 2016 for grain size, total organic carbon (TOC), total nitrogen (TN), organic phosphorus (OP), biogenic silica (BSi), δ13C and δ15N analyses. Significant correlation (p < 0.01) was observed between TOC and TN in summer and winter respectively, indicating that they have common source in both seasons. The spatiotemporal distributions of TOC, TN, OP and BSi were influenced by the sources and distribution of SOM, grain sizes and hydrodynamic conditions in the Maowei Sea. The overall ranges of δ13C (-26.86‰ to -23.01‰) and δ15N (2.54‰ to 9.82‰) and C/N ratio (5.83 to 18.67) showed that SOM is derived from mixed sources. The δ13C and δ15N-based three-end-member mixing model results revealed that >40% of the deposited SOM originates from terrestrial source during two seasons. The SOM from shellfish mariculture was seasonal, mainly deposited in the intensive mariculture areas, and its proportions were only higher than contributions from marine plankton in summer. Generally, this study indicates that shellfish biodepositions can significantly influence the cycle of carbon and other biogenic elements in the intensive mariculture areas. Nevertheless, the overall dominance of terrestrial and marine SOM suggests that the sources of SOM and factors influencing carbon cycling in the Maowei Sea do not exclusively depend on the intensity of mariculture activities.
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Affiliation(s)
- Cheng Xu
- College of Chemistry and Bioengineering, Guilin University of Technology, Guilin 541000, China; Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf, Beibu Gulf University, Qinzhou 535011, China
| | - Bin Yang
- Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf, Beibu Gulf University, Qinzhou 535011, China; Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University, Nanning 530004, China.
| | - Solomon Felix Dan
- Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf, Beibu Gulf University, Qinzhou 535011, China; Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China
| | - Dong Zhang
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University, Nanning 530004, China
| | - Riquan Liao
- Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf, Beibu Gulf University, Qinzhou 535011, China
| | - Dongliang Lu
- Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf, Beibu Gulf University, Qinzhou 535011, China
| | - Ruihuan Li
- State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Zhiming Ning
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University, Nanning 530004, China
| | - Shiqiu Peng
- State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
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Deng H, Tao Z, Gao Q, Yao L, Feng Y, Li Y, Ding J, Wang Z, Lyu X, Xu P. Variation of biogeochemical cycle of riverine dissolved inorganic carbon and silicon with the cascade damming. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:28840-28852. [PMID: 32418099 DOI: 10.1007/s11356-020-09174-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 05/04/2020] [Indexed: 06/11/2023]
Abstract
To investigate the variation of the biogeochemical cycle of riverine dissolved inorganic carbon (DIC) and silicon (DSi) with the cascade damming, the bicarbonate ([Formula: see text]), dissolved silicon (DSi), and other environmental factors within the cascade reservoirs of the lower reaches of Yalongjiang River, passing through the southeastern Qinghai-Tibet Plateau, were systematically analyzed by collecting water samples during the wet season and dry season from 2018 to 2019, respectively. The results showed that the lower ratio of DSi to[Formula: see text] (0.044 ± 0.001) was mainly controlled by the domination of carbonate mineral in the sedimentary rock of the Yalongjiang River drainage basin. The DSi:[Formula: see text] ratio was positively correlated with discharge (P < 0.05), and negatively correlated with the water retention time (P < 0.01) and chlorophyll a, implying that the variations of DSi:[Formula: see text] ratio were mainly determined by the rock chemical weathering processes and the hydrologic process outside the reservoirs and the biological processes within the cascade reservoirs. The phytoplankton photosynthetic process stoichiometrically assimilated DSi and [Formula: see text], resulted in 3.46 × 104 t·Si a-1 and 1.89 × 104 t·C a-1 sequestering in the cascade reservoirs, respectively. Compared with the situation of dam-free in the lower reaches of Yalongjiang River, the export flux of [Formula: see text] and DSi at the mouth of Yalongjiang River was reduced by 11.87% and 62.50%, respectively; the ratio of DSi:[Formula: see text] decreased by 36.01% for only building the Ertan dam and 53.15% for the cascade damming, respectively. The water renewal time prolonged from 45 to 126.6 days due to the regulation of the cascade reservoirs in the mainstream. Ultimately, a conceptual model on migration-transformation of DIC and DSi within the cascade reservoirs in the lower reaches of Yalongjiang River was established. These findings demonstrated that riverine cascade damming could extend the biogeochemical coupling cycle of DIC and DSi within the inland aquatic ecosystems and ensure the ecological environment security in the hot-dry valley.
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Affiliation(s)
- Haojun Deng
- School of Geography and Planning, Guangdong Key Laboratory for Urbanization and Geosimulation, Sun Yat-sen University, Guangzhou, 510275, China
| | - Zhen Tao
- School of Geography and Planning, Guangdong Key Laboratory for Urbanization and Geosimulation, Sun Yat-sen University, Guangzhou, 510275, China.
| | - Quanzhou Gao
- School of Geography and Planning, Guangdong Key Laboratory for Urbanization and Geosimulation, Sun Yat-sen University, Guangzhou, 510275, China
- Southern Laboratory of Ocean Science and Engineering (Guangdong, Zhuhai), Zhuhai, 519080, China
- Key Laboratory of Mineral Resource & Geological Processes of Guangdong Province, Guangzhou, 510275, China
| | - Ling Yao
- School of Geography and Planning, Guangdong Key Laboratory for Urbanization and Geosimulation, Sun Yat-sen University, Guangzhou, 510275, China
| | - Yong Feng
- School of Geography and Planning, Guangdong Key Laboratory for Urbanization and Geosimulation, Sun Yat-sen University, Guangzhou, 510275, China
| | - Yinhua Li
- School of Geography and Planning, Guangdong Key Laboratory for Urbanization and Geosimulation, Sun Yat-sen University, Guangzhou, 510275, China
| | - Jian Ding
- School of Geography and Planning, Guangdong Key Laboratory for Urbanization and Geosimulation, Sun Yat-sen University, Guangzhou, 510275, China
| | - Zhengang Wang
- School of Geography and Planning, Guangdong Key Laboratory for Urbanization and Geosimulation, Sun Yat-sen University, Guangzhou, 510275, China
| | - Xiaoxi Lyu
- School of Geography and Planning, Guangdong Key Laboratory for Urbanization and Geosimulation, Sun Yat-sen University, Guangzhou, 510275, China
| | - Peng Xu
- School of Geography and Planning, Guangdong Key Laboratory for Urbanization and Geosimulation, Sun Yat-sen University, Guangzhou, 510275, China
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Wang H, Li M, Sun C, Wu W, Ran X, Zang J. Variability in water chemistry of the Three Gorges Reservoir, China. Heliyon 2020; 6:e03610. [PMID: 32322702 PMCID: PMC7168739 DOI: 10.1016/j.heliyon.2020.e03610] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 01/20/2020] [Accepted: 03/12/2020] [Indexed: 11/25/2022] Open
Abstract
The environmental influence of the Three Gorges Reservoir (TGR) on the Changjiang River has been widely studied since the Three Gorges Dam (TGD) began operation in 2003. However, the changes in water chemistry in the reservoir in response to damming effect variations are poorly documented in the area of this large reservoir. The results suggest that in comparison to the water chemistry before the TGR operation, the inflow concentrations of Mg2+, K+, Na+ and Cl− increased in the TGR, and the abundance of Ca2+ and HCO3- decreased in the inflow in the period after the TGR filling as a result of climate change and human activities in the Changjiang River basin. The ionic composition in the TGR is primarily controlled by contributions from the upstream region of the Changjiang River but was modified by the interaction between water and rocks within the TGR. The concentrations of most major ions as well as the equivalent ratios of the major ions increased in the TGR after the operation of TGD. This change yielded a 6% increase in the major ion loading downstream of the TGD. The Three Gorges area strongly contributes to the increase in ion loading in the TGR due to enhanced water and rock interactions in comparison with the period before TGD operation.
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Affiliation(s)
- Hao Wang
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, 266100, China
| | - Menglu Li
- First Institute of Oceanography, Ministry of Natural Resources, Qingdao, 266061, China
| | - Cece Sun
- First Institute of Oceanography, Ministry of Natural Resources, Qingdao, 266061, China
| | - Wentao Wu
- First Institute of Oceanography, Ministry of Natural Resources, Qingdao, 266061, China
| | - Xiangbin Ran
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, 266100, China.,First Institute of Oceanography, Ministry of Natural Resources, Qingdao, 266061, China.,Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
| | - Jiaye Zang
- First Institute of Oceanography, Ministry of Natural Resources, Qingdao, 266061, China
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Wang WF, Li SL, Zhong J, Maberly SC, Li C, Wang FS, Xiao HY, Liu CQ. Climatic and anthropogenic regulation of carbon transport and transformation in a karst river-reservoir system. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 707:135628. [PMID: 31784157 DOI: 10.1016/j.scitotenv.2019.135628] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 11/14/2019] [Accepted: 11/17/2019] [Indexed: 06/10/2023]
Abstract
The effect of dams on dissolved inorganic carbon (DIC) transport and riverine ecosystems is unclear in karst cascade reservoirs. Here, we analyzed water samples from a karst river system with seven cascade reservoirs along the Wujiang River, southwestern China, during one hydrological year. From upstream to downstream, the average concentration of DIC increased from 2.2 to 2.6 mmol/L and its carbon isotope composition (δ13CDIC) decreased from -8.0 to -10‰. Meanwhile, the air temperature (Ta) increased from 20.3 °C to 26.7 °C and 10 °C to 13.7 °C in the warm and cold seasons, respectively. The results suggest that a cascade of dams has a stronger effect on DIC dynamics and retention than a single dam. The good correlation between Ta/HRT (hydraulic retention time) and Δ[DIC] as well as Δ[δ13CDIC] mean that Ta and HRT affected the magnitude of the damming effect by altering changes in concentration of DIC and δ13CDIC in the reservoir compared to the inflowing water. In particular, daily regulated reservoirs with short retention times acted more like river corridors and had a smaller effect on carbon dynamics, so modulating retention time might be used reduce the effect of dams on the riverine ecosystem.
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Affiliation(s)
- Wan-Fa Wang
- Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China
| | - Si-Liang Li
- Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China; State Key laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin 300072, China.
| | - Jun Zhong
- Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China
| | - Stephen C Maberly
- Lake Ecosystems Group, NERC Centre for Ecology & Hydrology, Lancaster Environment Centre, Lancaster, UK
| | - Cai Li
- School of Urban and Environment Science, Huaiyin Normal University, Huaian 223300, China
| | - Fu-Shun Wang
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200433, China
| | - Hua-Yun Xiao
- Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China; State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China
| | - Cong-Qiang Liu
- Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China
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Dan SF, Liu SM, Yang B, Udoh EC, Umoh U, Ewa-Oboho I. Geochemical discrimination of bulk organic matter in surface sediments of the Cross River estuary system and adjacent shelf, South East Nigeria (West Africa). THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 678:351-368. [PMID: 31077914 DOI: 10.1016/j.scitotenv.2019.04.422] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 04/27/2019] [Accepted: 04/28/2019] [Indexed: 06/09/2023]
Abstract
Knowledge of the sources, distribution and fate of organic matter (OM) in estuarine and adjacent shelf sediments are important for the understanding of the global biogeochemical cycles. Bulk organic carbon (C-org), total nitrogen (TN), biogenic silica (BSi), stable carbon (δ13C-org) and nitrogen (δ15N) isotopes, and sediment grain sizes were measured to study the spatial distributions and sources of sediment OM in the Cross River estuary system (CRES) and adjacent shelf. Surface sediments in the CRES were composed of clayey silt and sandy silt, while the adjacent shelf sediments were mainly silty sand. The range of the studied parameters was -28.79‰ to -22.20‰ for δ13C-org, -1.32‰-6.31‰ for δ15N, 6.7-29.2 for C-org/N ratios, 0.08%-0.33% for TN, 0.24‰-0.74‰ for BSi, and 0.47%-5.28% for C-org, and their spatial distributions showed a general decreasing trend in both the terrestrial and estuarine OM from the riverine regions to the adjacent shelf. Based on the three-end-member mixing model using the δ13C and δ15N isotopic values, ~58.01 ± 15.32% of sediment OM are derived from terrestrial sources dominated by C3 vascular plants, while ~26.34 ± 9.71% are attributed to estuarine sources dominated by aquatic macrophytes, and ~15.65 ± 12.37% for marine plankton source. Other sources of OM identified included soils underlain C3 vascular plants and agricultural farms enriched with N, sewage, and petroleum hydrocarbons. The relationship between C-org vs. BSi, and the atomic BSi/Corg ratios suggested that diatoms also play an important role in OM sequestration in surface sediments of the CRES and adjacent shelf. The correlations of the δ13C-org and δ15N isotopic values vs. C-org/N ratios resulted in scatter plots, indicating that the distributions of sediment OM in the CRES and adjacent shelf are influenced by post depositional processes, fixed inorganic N adsorbed on fine-grained sediments, microbial degradation, as well as sediment grain size.
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Affiliation(s)
- Solomon Felix Dan
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Institute for Advanced Ocean Study, Ocean University of China, Qingdao 266100, PR China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, PR China
| | - Su-Mei Liu
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Institute for Advanced Ocean Study, Ocean University of China, Qingdao 266100, PR China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, PR China.
| | - Bin Yang
- Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf, Beibu Gulf University, Qinzhou 535011, PR China
| | - Enobong Charles Udoh
- State Key Laboratory of Marine Geology, College of Ocean and Earth Science, Tongji University, Shanghai 200092, PR China
| | - Unyime Umoh
- State Key Laboratory of Marine Geology, College of Ocean and Earth Science, Tongji University, Shanghai 200092, PR China
| | - Ita Ewa-Oboho
- Department of Marine Biology, Akwa Ibom State University, Ikot Akpaden, Nigeria
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13
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Variation of Diatoms and Silicon in a Tributary of the Three Gorges Reservoir: Evidence of Interaction. WATER 2019. [DOI: 10.3390/w11071369] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
To gain insight into the variation of diatoms and silicon and their interaction in a tributary of the Three Gorges Reservoir (TGR), the Xiangxi River was chosen as a representative tributary, and dissolved silicon (DSi) and biogenic silicon (BSi) were investigated monthly from February 2015 to December 2016, accompanied by diatom species composition and cell density analyses. The results showed that the diatom population and its relationship with silicon concentration were significantly different between the lacustrine zone and riverine zone (P < 0.05). The cell density in the lacustrine zone (6.20 × 105 ~ 9.97 × 107 cells/L) was significantly higher than that in the riverine zone (7.90 × 104 ~ 1.81 × 107 cells/L) (P < 0.01). Water velocity was a key factor in determining the diatom species composition. Centric diatoms were the dominant species in the lacustrine zone, and pennate diatoms were the primary species in the riverine zone, which indicated that centric diatoms outcompete pennate diatoms under the influence of the TGR’s operation. BSi showed a significant linear relationship with the cell density. DSi had a significant negative relationship with the cell density in the lacustrine zone, while no significant relationship was found in the riverine zone. This meant that the main contributor to BSi was diatoms, but DSi was primarily affected by water discharge, not diatom uptake. It could be deduced that the spatiotemporal heterogeneity of diatom communities was influenced by the TGR’s operation. Silicon cycling in the tributary was significantly affected by diatoms, and the current concentration of DSi was sufficient for diatom growth and showed no significant effects on the diatom community.
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Li D, Dong M, Liu S, Chen H, Yao Q. Distribution and budget of biogenic silica in the Yangtze Estuary and its adjacent sea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 669:590-599. [PMID: 30889448 DOI: 10.1016/j.scitotenv.2019.03.144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 03/06/2019] [Accepted: 03/09/2019] [Indexed: 06/09/2023]
Abstract
Field investigations of the Yangtze Estuary and its adjacent sea were carried out from July to August 2011. The distribution, source, transportation and transformation of biogenic silica (BSi) in suspended particulate matter (SPM) and core sediments were comprehensively investigated; dissolved silica (DSi) in pore water was also analyzed in this work. The budgets of reactive silica (RSi) and BSi in the East China Sea (ECS) were initially constructed on the basis of the above survey. The results indicated that the BSi distribution in this area was mainly affected by the input of the Yangtze River and Taiwan Warm Current, which was significantly correlated with SPM. The RSi flux input by rivers accounts for 17.6% of the total source of RSi in the ECS. Thus, these findings combined with the horizontal distribution of BSi in the Yangtze Estuary and its adjacent sea indicate that riverine input has a profound influence on the primary production of diatoms in the euphotic zone. Submarine groundwater exchange accounts for 22.3% of the DSi input, especially in the upwelling region, which will directly affect the euphotic nutrient structure. The DSi benthic flux from pore water to upper water exceeds riverine input by 3-fold, accounting for 11.5% of primary production in the ECS, which can alleviate the Si limiting effect caused by the decrease in DSi flux from the Yangtze runoff in recent years. Approximately 75.5% of BSi is dissolved and re-engaged in the ECS silicon cycle in the settlement process.
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Affiliation(s)
- Dandan Li
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China
| | - Mingfan Dong
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China
| | - Shumin Liu
- College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China
| | - Hongtao Chen
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China
| | - Qingzhen Yao
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266100, China; College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China.
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Liu Y, Deng B, Du J, Zhang G, Hou L. Nutrient burial and environmental changes in the Yangtze Delta in response to recent river basin human activities. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 249:225-235. [PMID: 30893635 DOI: 10.1016/j.envpol.2019.03.030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 03/05/2019] [Accepted: 03/10/2019] [Indexed: 06/09/2023]
Abstract
High resolution sediment records in the Yangtze Delta front were constructed to reveal recent environmental changes in response to river basin human activities. Increases in nutrient and organic C influxes that began in the 1950s, together with elevated primary productivity and increased chemical fertilizer application, suggested a shift toward anthropogenic-predominated environmental changes during this period. The depletion of total organic C (TOC), total N (TN), and biogenic Si (BSi), along with the decline in sedimentation rate and coarsening of sediment coincided with the development of hydrological engineering in the river basin from the 1980s. Reservoir Si retention substantially altered river mouth primary productivity community composition from diatoms to non-diatoms, thereby changing the BSi/TOC molar ratio in the sediment profile. Estimation of biogenic component burial fluxes was conducted to assess the variation and potential impacts. A recent dramatic decline in biogenic component burial in the delta area suggested a low nutrient removal efficiency in this region, due to the decrease in sediment discharge. Consequently, more nutrients have been further transported to the inner shelf and open waters instead of being buried in the delta sediment, thereby increasing the environmental pressure in the Yangtze Delta and adjoining coastal area.
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Affiliation(s)
- Yueying Liu
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, 200241, China
| | - Bing Deng
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, 200241, China.
| | - Jinzhou Du
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, 200241, China
| | - Guosen Zhang
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, 200241, China
| | - Lijun Hou
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, 200241, China
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Hong H, Dai M, Lu H, Liu J, Zhang J, Yan C. Risk assessment and driving factors for artificial topography on element heterogeneity: Case study at Jiangsu, China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 233:246-260. [PMID: 29096297 DOI: 10.1016/j.envpol.2017.10.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Revised: 10/05/2017] [Accepted: 10/05/2017] [Indexed: 06/07/2023]
Abstract
The rapid expansion of construction related to coastal development evokes great concern about environmental risks. Recent attention has been focused mainly on factors related to the effects of waterlogging, but there is urgent need to address the potential hazard caused by artificial topography: derived changes in the elemental composition of the sediments. To reveal possible mechanisms and to assess the environmental risks of artificial topography on transition of elemental composition in the sediment at adjoining zones, a nest-random effects-combined investigation was carried out around a semi-open seawall. The results implied great changes induced by artificial topography. Not only did artificial topography alter the sediment elemental composition at sites under the effect of artificial topography, but also caused a coupling pattern transition of elements S and Cd. The biogeochemical processes associated with S were also important, as suggested by cluster analysis. The geo-accumulation index shows that artificial topography triggered the accumulation of C, N, S, Cu, Fe, Mn, Zn, Ni, Cr, Pb, As and Cd, and increased the pollution risk of C, N, S, Cu, As and Cd. Enrichment factors reveal that artificial topography is a new type of human-activity-derived Cu contamination. The heavy metal Cu was notably promoted on both the geo-accumulation index and the enrichment factor under the influence of artificial topography. Further analysis showed that the Cu content in the sediment could be fitted using equations for Al and organic carbon, which represented clay mineral sedimentation and organic matter accumulation, respectively. Copper could be a reliable indicator of environmental degradation caused by artificial topography.
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Affiliation(s)
- Hualong Hong
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, PR China
| | - Minyue Dai
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, PR China
| | - Haoliang Lu
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, PR China; State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361102, PR China
| | - Jingchun Liu
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, PR China
| | - Jie Zhang
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, PR China
| | - Chongling Yan
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, PR China; State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361102, PR China.
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