Significance of dredging on sediment denitrification in Meiliang Bay, China: a year long simulation study.

An experiment for studying the effects of sediment dredging on denitrification in sediments was carried out through a one-year incubation of undredged (control) and dredged cores in laboratory. Dredging the upper 30 cm of sediment can significantly affect physico-chemical characteristics of sediments. Less degradation of organic matter in the dredged sediments was found during the experiment. Denitrification rates in the sediments were estimated by the acetylene blockage technique, and ranged from 21.6 to 102.7 nmol N2/(g dry weight (dw) x hr) for the undredged sediment and from 6.9 to 26.9 nmol N2/(g dw x hr) for dredged sediments. The denitrification rates in the undredged sediments were markedly higher (p < 0.05) than those in the dredged sediments throughout the incubation, with the exception of February 2006. The importance of various environmental factors on denitrification was assessed, which indicated that denitrification was regulated by temperature. Nitrate was probably the key factor limiting denitrification in both undredged and dredged sediments. Organic carbon played some role in determining the denitrification rates in the dredged sediments, but not in the undredged sediments. Sediment dredging influenced the mineralization of organic matter and denitrification in the sediment; and therefore changed the pattern of inherent cycling of nitrogen.

[1]  D. Hayes,et al.  Simulation of resuspended sediments resulting from dredging operations by a numerical flocculent transport model. , 2007, Chemosphere.

[2]  J. Silverstein,et al.  Denitrification Potential in Stream Sediments Impacted by Acid Mine Drainage: Effects of pH, Various Electron Donors, and Iron , 2006, Microbial Ecology.

[3]  王建军,et al.  太湖沉积物-水界面生源要素迁移机制及定量化——2．磷释放的热力学机制及源-汇转换 , 2006 .

[4]  R. Laughlin,et al.  A spatial study of denitrification potential of sediments in Belfast and Strangford Loughs and its significance. , 2000, The Science of the total environment.

[5]  M. Dokulil,et al.  Changes of nutrients and phytoplankton chlorophyll-a in a large shallow lake, Taihu, China: an 8-year investigation , 2003, Hydrobiologia.

[6]  W. Boynton,et al.  Ammonium recycling versus denitrification in chesapeake bay sediments , 1990 .

[7]  J. Morris,et al.  Potential denitrification rates in deep sediments from the southeastern coastal plain. , 1988, Environmental science & technology.

[8]  F. D'asaro,et al.  Scaling properties of topologically random channel networks , 1996 .

[9]  Boqiang Qin,et al.  Dynamics of sediment resuspension and the conceptual schema of nutrient release in the large shallow Lake Taihu, China , 2004 .

[10]  G. A. Burton,et al.  Evaluating the effectiveness of contaminated-sediment dredging. , 2008, Environmental science & technology.

[11]  J. Sørensen.  Denitrification Rates in a Marine Sediment as Measured by the Acetylene Inhibition Technique , 1978, Applied and environmental microbiology.

[12]  W. Lewis,et al.  Denitrification as a component of the nitrogen budget for a large plains river , 1997 .

[13]  W. Wiebe,et al.  Effect of salinity and inorganic nitrogen concentrations on nitrification and denitrification rates in intertidal sediments and rocky biofilms of the Douro River estuary, Portugal. , 2005, Water research.

[14]  P. Bradley,et al.  Effects of Carbon and Nitrate on Denitrification in Bottom Sediments of an Effluent‐Dominated River , 1995 .

[15]  范成新,et al.  湖泊底泥疏浚环境效应：I．内源磷释放控制作用 , 2009 .

[16]  B. Whitton,et al.  Denitrification in sediments of the freshwater tidal Yorkshire Ouse , 1998 .

[17]  Guoxiang Wang,et al.  A physico-ecological engineering experiment for water treatment in a hypertrophic lake in China , 1998 .

[18]  Joshua A. Mackie,et al.  Declining metal levels at Foundry Cove (Hudson River, New York): response to localized dredging of contaminated sediments. , 2007, Environmental pollution.

[19]  W. Payne.  Reduction of nitrogenous oxides by microorganisms. , 1973, Bacteriological reviews.

[20]  P. Groffman,et al.  Denitrification potential in urban riparian zones. , 2003, Journal of environmental quality.

[21]  V. Ruban,et al.  Selection and evaluation of sequential extraction procedures for the determination of phosphorus forms in lake sediment. , 1999, Journal of environmental monitoring : JEM.

[22]  S. Seitzinger.  Denitrification in freshwater and coastal marine ecosystems: Ecological and geochemical significance , 1988 .

[23]  J. Kohl,et al.  Assessment of the long-term effectiveness of sediment dredging to reduce benthic phosphorus release in shallow Lake Müggelsee (Germany) , 1999, Hydrobiologia.

[24]  H. Golterman,et al.  The Chemistry of Phosphate and Nitrogen Compounds in Sediments , 2004, Springer Netherlands.

[25]  G. Hofman,et al.  Soil properties influencing the denitrification potential of Flemish agricultural soils , 2003, Biology and Fertility of Soils.

[26]  J. P. Riley,et al.  A modified single solution method for the determination of phosphate in natural waters , 1962 .

[27]  R. Naiman,et al.  Potential Denitrification Activity in the Landscape of a Western Alaska Drainage Basin , 2003, Ecosystems.

[28]  B. Cavari,et al.  Denitrification in Lake Kinneret in the presence of oxygen , 1977 .

[29]  A. Devol,et al.  Benthic nutrient regeneration and denitrification on the Washington continental shelf , 1987 .

[30]  H. Paerl,et al.  Estimating denitrification rates in estuarine sediments: A comparison of stoichiometric and acetylene based methods , 1996 .

[31]  B. Whitton,et al.  Denitrification and nitrous oxide production in sediments of the Wiske, a lowland eutrophic river , 1998 .

[32]  J. Robinson,et al.  Impacts of aggregate dredging on sediment composition and associated benthic fauna at an offshore dredge site in the southern North Sea. , 2005, Marine environmental research.

[33]  P. Brezonik,et al.  Comparison of denitrification rate estimation techniques in a large, shallow lake , 1983 .

[34]  T. Datry,et al.  Do tubificid worms influence the fate of organic matter and pollutants in stormwater sediments? , 2005, Environmental pollution.

[35]  范成新,et al.  湖泊底泥疏浚环境效应:II.内源氮释放控制作用 , 2009 .

[36]  K. S. Pfenning,et al.  Effect of nitrate, organic carbon, and temperature on potential denitrification rates in nitrate-rich riverbed sediments , 1997 .

[37]  D. Burska,et al.  The Impact of Dredging Deep Pits on Organic Matter Decomposition in Sediments , 2004 .

[38]  S. Seitzinger,et al.  Denitrification and nitrous oxide production in a coastal marine ecosystem1 , 1984 .

[39]  Qingman Li,et al.  Dredging effects on P status and phytoplankton density and composition during winter and spring in Lake Taihu, China , 2007, Hydrobiologia.

[40]  R. Berner,et al.  Kinetic models for the early diagenesis of nitrogen, sulfur, phosphorus and silicon in anoxic marine sediments , 1974 .

[41]  A. Enrich-Prast,et al.  Potential denitrification in submerged natural and impacted sediments of Lake Batata, an Amazonian lake , 2001, Hydrobiologia.

[42]  T. Murphy,et al.  Review of emerging issues in sediment treatment , 1999 .