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Seasonal response of nitrogen exchange fluxes to crab disturbance at Sediment-water interface in coastal tidal wetlands

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water Science and Engineering 2024年第2期17卷 129-138页

作者： Guo-fen Hua Shang-qing Liu Xiang-dong Liu Jin-li Li Yue Fang Wen-ting Xie Xiang Xu College of water Conservancy and Hydroelectric Power Hohai UniversityNanjing 210098China College of Renewable Energy Hohai UniversityNanjing 210098China

Coastal wetlands are hotspots for nitrogen(N)cycling,and crab burrowing is known to transform N in intertidal marsh soils.However,the underlying mechanisms remain unclear.This study conducted field experiments and used indoor control test devices to investigate the seasonal response of nitrogen to crab disturbance at the Sediment-water interface in coastal tidal flat wetlands.The results showed that crab disturbance exhibited significant seasonality with large seasonal differences in cave density and depth.Due to crab disturbance,nitrogen fuxes at the Sediment-water interface were much greater in the box with crabs than in the box without crabs.In summer,NH-N showed a positive flux from the sediment to the overlying water,but NO2-N and NOg-N showed positive fluxes from the sediment to the overlying water only in early stages.In winter,NH-N showed a positive flux from the sediment to the overlying water,but NO-N and NO,-N both exhibited positive and negative fluxes.These results indicated that the presence of crab burrows can cause the aerobic layer to move downward by approximately 8-15 cm in summer and directly promote nitrification at the sediment surface.

关键词： Coastal tidal flat wetland Crab disturbance Nitrogen flux Nitrification Denitrification Sediment-water interface

The Effect of Bioturbation Activity of the Ark Clam Scapharca subcrenata on the Fluxes of Nutrient Exchange at the sediment–water interface

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Journal of Ocean University of China 2020年第1期19卷 232-240页

作者： ZHANG Shuo FANG Xin ZHANG Junbo YIN Fang ZHANG Hu WU Lizhen KITAZAWA Daisuke College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of EducationShanghai Ocean UniversityShanghai 201306China National Demonstration Center for Experimental Fisheries Science Education(Shanghai Ocean University Shanghai 201306China National Engineering Research Center for Oceanic Fisheries Shanghai Ocean UniversityShanghai 201306China College of Ocean Science and Engineering Shanghai Maritime UniversityShanghai 201306China Maine Fisheries Research Institution of Jiangsu Nantong 226000China Lianyungang City Oceanic and Fishery Administration Lianyungang 222002China Institute of Industrial Science The University of Tokyo5-1-5 KashiwanohaKashiwaJapan

Filter-feeding shellfish are common benthos and significantly affect the biogeochemical cycle in the shallow coastal ecosystems.Ark clam Scapharca subcrenata is one of the widely cultured bivalve species in many coastal areas owing to its tremendous economic value.However,there is little information regarding the effects of the bioturbation of S.subcrenata on the fluxes of nutrient exchange in the Sediment-water interface(SWI).In this regard,S.subcrenata was sampled during October 2016 to determine the effects of its bioturbation activity on the nutrient exchange flux of the SWI.The results showed that the biological activity of S.subcrenata could increase the diffusion depth and the rate of the nutrients exchange in the sediments.The bioturbation of S.subcrenata could allow the nutrients to permeate into the surface sediments at 6-10cm and increase the release rate of nutrients at the SWI.The releasing fluxes of DIN and PO43−-P in the culture area were found to be around three times higher than that in the non-cultured region.The culture of S.subcrenata has been proved to be an important contributor to nutrient exchange across the SWI in the farming area of Haizhou Bay.Nutrients exchange in the SWI contributes a part of 86%DIN,71%PO43−-P and 18%SiO32−-Si for the aquaculture farm.

关键词： bioturbation nutrients exchange flux ark clam Sediment-water interface

Environmental geochemistry of arsenic in Sediment-water interface of Poyang Lake, China

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Acta Geochimica 2006年第S1期 142-143页

作者： Mengxia LIAO1, Tianlong DENG1,2 1 College of Chemistry and Chemical Engineering, Chengdu University of Technology, Chengdu 610059, China2 Qinghai Institute of Salt Lakes, Chinese Academy of Sciences,Xining 810008, China

The Study of Phosphorus Release on Sediment-water interface

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科技经济导刊 2018年第5期 50-50页

作者：李丽王伟伟陆香珍青岛大学化学化工学院

sediment is one of the major controlling factors for phosphate levels in many aquatic systems,the study of phosphorus release on Sediment-water interface under hypoxic environment include the chemical behavior of iron reveal its effect on the cycle of phosphorus in the hypoxic environment.the study would enrich the knowledges of phosphorus cycling in the hypoxic area.

关键词： Sediment-water interface phosphorus release hypoxic environment

Changes of DOM and its correlation with internal nutrient release during cyanobacterial growth and decline in Lake Chaohu, China

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Journal of Environmental Sciences 2023年第2期124卷 769-781页

作者： Yan Bao Tao Huang Chengwu Ning Tingting Sun Pengliang Tao Jie Wang Qingye Sun School of Resources and Environmental Engineering Anhui UniversityHefei 230601China Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration Anhui UniversityHefei 230601China

The seasonal changes in dissolved organic matter(DOM),and its correlation with the release of internal nutrients during the annual cycle of cyanobacteria in the eutrophic Lake Chaohu,China,were investigated from four sampling periods between November 2020 and July 2021.The DOM fluorescence components were identified as protein-like C1,microbial humic-like C2,and terrestrial humic-like C3.The highest total fluorescence intensity(FT)of DOM in sediments during the incubation stage is due to the decomposition and degradation of cyanobacteria remains.The lowest humification of DOM and the highest proportion of C1 in waters during the initial cyanobacterial growth indicate that fresh algae are the main source.The highest molecular weight of DOM and FT of the C2 in sediments during cyanobacterial outbreaks indicate the concurrent deposition of undegraded cyanobacterial remains and microbial degradation.The components of DOM are affected mainly by the dissolved total phosphorus in waters,while the temperature drives the annual cycle of cyanobacteria.The decreasing C1 in sediments and increasing nutrients in waters from the cyanobacterial incubation to outbreak indicate that mineralization of algal organic matter contributes importantly to the release of internal nutrients,with the strongest release of phosphorus observed during the early growth of cyanobacteria.The humic-like C2 and C3 components could also affect the dynamics of internal phosphorus through the formation of organic colloids and organic–inorganic ligands.The results show that the degradation of DOM leads to nutrients release and thus supports the continuous growth of cyanobacteria in eutrophic Lake Chaohu.

关键词： Eutrophication Shallow lake Sediment-water interface Algal blooms Fluorescence components PARAFAC

The age and quality of pond bottom soil affect water quality and production of Pangasius hypophthalmus in the tropical environment

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Aquaculture and Fisheries 2023年第3期8卷 296-304页

作者： Saberina Hasibuan Syafriadiman Syafriadiman Netti Aryani Muhammad Fadhli Monalisa Hasibuan Environmental Quality Laboratory Department of Aquaculture Faculty of Fisheries and Marine SciencesUniversity of RiauPekanbaru28293Indonesia Department of Aquaculture Faculty of Fisheries and Marine Sciences University of RiauPekanbaru28293Indonesia Graduate of Aquaculture Faculty of Fisheries and Marine Sciences University of RiauPekanbaru28293Indonesia Researcher at the Board of Research and Development of Riau Province Indonesia

Pangasius hypophthalmus is the most cultured freshwater fish by smallholder farmers in Indonesia.One of the main challenges in the production is the highly weathered and infertile soils on the bottom of a pond that influences aquaculture productivity.This work investigated the effects of pond age on soil quality,water quality,benthic algae population,and P.hypophthalmus production.We carried out a field experiment in a randomized design with pond age of 4 levels:Ponds aged 0-5 years(P1),6-10 years(P2),11-15 years(P3),and 16-20 years(P4).The soil is a Typic Palaeudult(Ultisol),and fish were grown for three months.The results showed that the chemical soil quality parameters and soil organic matter content increased linearly with pond age,resulting in the enhancement of water quality parameters.The increase in nitrate and phosphate directly affected benthic algae richness.These,in turn,in the highest fish production in P3,6.4 kg/m^(2),specific growth rate was 3.76%/d,survival rate of 66.7%,and feed conversion ratio of 1.8%.Linear correlation coefficients indicated that the contents of total N,total P,and organic carbon in the bottom soil of the pond were related to the increase in phosphate,nitrate,and organic matter content in pond water.Total N content,total P,carbon organic matter,C/N ratio,and CEC value in pond bottom soil significantly correlated to Pangus fish production.C/N ratio,CEC value in pond bottom soil,and CO_(2)concentration in pond water significantly correlated to fish survival rate.Multiple linear regression indicated that fish production was significantly related to the pond age,water NH3,total alkalinity,and soil total P and C/N ratio(R^(2)=0.99,P<0.001).Increased soil C/N ratio caused a negative effect on fish production.The results suggested that old-aged ponds,with proper management,act as a nutrient sink,resulting in increased aquaculture production.The implementation of the best practices will benefit the Pangus culture in the tropical environment.

关键词： Benthic algae Production Soil pond Soil quality Sediment-water interface

Efects of physical and chemical characteristics of surface sediments in the formation of shallow lake algae-induced black bloom

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Journal of Environmental Sciences 2013年第12期25卷 2353-2360页

作者： Qiushi Shen Cheng Liu Qilin Zhou Jingge Shang Lei Zhang ChengXin Fan University of Chinese Academy of Sciences State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of Sciences

Surface sediments are closely related to lake black blooms. The dissolved oxygen （DO） distribution and its penetration depth in surface sediments as well as the migration and transformation of redox sensitive elements such as Fe and S at the Sediment-water interface are important factors that could influence the formation of the black bloom. In this study, dredged and undredged sediment cores with different surface properties were used to simulate black blooms in the laboratory. The Micro Profiling System was employed to explore features of the DO and ∑H2S distribution at the Sediment-water interface. Physical and chemical characteristics in sediments and pore waters were also analyzed. The results showed that sediment dredging effectively suppressed the black blooms. In the undredged treatment, DO penetration depth was only 50 μm. Fe^2＋ concentrations, ∑H2S concentrations, and ∑H2S production rates were remarkably higher in surface sediments and pore waters compared to control and dredged treatments. Furthermore, depletion of DO and accumulation of Fe^2＋ and ∑H2S in surface sediments and pore waters provided favorable redox environments and necessary material sources for the blooms. The study results proved that physical and chemical characteristics in surface sediments are important factors in the formation of the black bloom, and could provide scientific guidance for emergency treatment and long-term pre-control of black blooms.

关键词： black bloom Sediment-water interface dredging sediment micro interface lake

Impact of environmental variables on spatial and seasonal internal phosphorus loading in a mesoeutrophic lake

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International Journal of sediment Research 2019年第1期34卷 14-26页

作者： Katarzyna Kowalczewska-Madura Ryszard Go?dyn Julia Bogucka Katarzyna Strzelczyk Department of water Protection Faculty of BiologyAdam Mickiewicz University

Strzeszynskie Lake was formerly a slightly eutrophic(meso-eutrophic) water body. The aim of the current research was to define variables on both spatial and seasonal internal phosphorus loading from bottom sediments at five stations located in zones varying in depth, oxygenation, macrophyte presence,and uses of the neighboring catchment area. Ex situ experiments done with the use of intact bottom sediment cores have shown that the highest phosphorus release occurred in the deepest part of the lake and reached 3.6 mg P/m~2 d under anoxic conditions during summer thermal stratification. In turn, the internal loading from littoral sediments, which were well aerated all year round, was clearly lower.Furthermore, phosphorus accumulation in the bottom sediment was observed to reach a maximum of 1.45 mg P/m~2 d in autumn. A comparison of the internal loading intensity in lake zones with different land uses of the neighboring catchment area has shown slightly higher values at stations adjacent to the forest catchment area than those used for recreation. Changes in the land use of the catchment area of Strzeszynskie Lake, especially the increase in impermeable surfaces, have led to an increased inflow of external loads after heavy rains, resulting in deterioration in water quality and a delayed increase in internal loading.

关键词： Bottom sediments Interstitial water Bottom water Internal loading Sediment-water interface

Simulation on phosphorus release characteristics of Poyang Lake sediments under variable water levels and velocities

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Journal of Geographical Sciences 2017年第6期27卷 697-710页

作者： TONG Yali LIANG Tao WANG Lingqing LI Kexin Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

Since the construction of the Three Gorges Dam, the Poyang Lake hydrological characteristics obviously changed. During the impoundment period of the Three Gorges Reservoir, the hydrodynamic factors of Poyang Lake varied. water level dropped, the velocity decreased and water exchange time lengthened, which changed the release of phosphorous from sediments. In order to investigate how the hydrodynamic factors influence the release of phosphorous from sediments, we used a two-way annular flume device to simulate the release characteristics of phosphorous from sediments under variable water levels and velocities. We found that both water level rising and velocity increasing could enhance the distur- bance intensity to sediments, which caused the increase of suspended solids （SS） concentration, total phosphorus （TP） concentration in the overlying water, and the ability that phosphorus released to overlying water from sediments enhanced as well： when overlying water velocity maintained 0.3 m/s, SS concentration increased to 4035.85 mg/L at the water level 25 cm which was about 25 times compared to the minimum value and TP concentration in the overlying water also reached the maximum value at the water level 25 cm which was 1.2 times that of the value at 10 cm; when water level maintained 15 cm, SS concentration increased to 4363.35 mg/L at the velocity of 0.5 m/s which was about 28 times compared to the value of 0 m/s, and TP concentration in the overlying water increased from 0.11 mg/L to 0.44 mg/L. When the water level maintained 15 cm, the phosphorous release rate reached the maximum value of 4,86 mg/（md） at 0.4 m/s. The concentration of total dissolved phosphorous （TDP） and soluble reactive phosphate （SRP） both in overlying water and Sediment-water interface were negatively correlated with pH. Using the parabolic equation, the optimum water level at a velocity of 0.3 m/s was calculated to be 0.57 cm, and the optimum velocity at water level of 15 cm was found to be 0.2 m/s.

关键词： hydrodynamic factors Sediment-water interface total phosphorous total dissolved phosphorous soluble reactive phosphate Poyang Lake