1887

Abstract

Ammonia-oxidizing archaea (AOA) have recently been found to be potentially important in nitrogen cycling in a variety of environments, such as terrestrial soils, wastewater treatment reactors, marine waters and sediments, and especially in estuaries, where high input of anthropogenic nitrogen is often experienced. The sedimentary AOA diversity, community structure and spatial distribution in the Changjiang Estuary and the adjacent East China Sea were studied. Multivariate statistical analysis indicated that the archaeal genotype communities could be clustered according to sampling transects, and the station located in an estuarine mixing zone harboured a distinct AOA community. The distribution of AOA communities correlated significantly with the gradients of surface-water salinity and sediment sorting coefficient. The spatial distribution of putative soil-related AOA in certain sampling stations indicated a strong impact of the Changjiang freshwater discharge on the marine benthic microbial ecosystem. Besides freshwater, nutrients, organic matter and suspended particles, the Changjiang Diluted Water might also contribute to the transport of terrestrial archaea into the seawater and sediments along its flow path.

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2008-07-01
2019-10-14
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Rarefaction curves of the marine archaeal gene clone libraries constructed with unique RFLP phylotypes (a) or OTUs defined with 95% sequence similarity cutoff (b) using sediment samples from the Changjiang Estuary and the adjacent East China Sea. [ PDF] (231 kb) Principal components analysis of the sedimentary ammonia-oxidizing archaea (AOA) communities with weighted UniFrac using the archaeal AmoA protein sequences recovered from the Changjiang Estuary and adjacent East China Sea. Shown is the plot of the first two principal coordinate axes for PCoA and the distribution of the AOA communities (designated with the sampling station names) in response to these axes. [ PDF] (230 kb) The 'CCA' ordination plot (CCA, canonical correspondence analysis) for the first two CCA dimensions of the relationship between the sedimentary AOA community compositions with the hydrochemical parameters of the surface-water (_S) and bottom-water (_B) environments in the Changjiang Estuary and adjacent East China Sea before model optimization via manual deselection of collinear variables and automatic forward selection with the Monte Carlo permutation procedure. This plot shows the apparent collinearity of some of the environmental variables, such as surface-water salinity, conductivity, density, bottom-water dissolved oxygen and water depth. Surface-water temperature and DO were not included in the analysis due to their diel variations and our sampling time inconsistency for their in situ measurements. Abbreviations: CD, conductivity; DT, water depth; SL, salinity; SG, density; TB, turbidity; TM, temperature. [ PDF] (231 kb) The 'CCA' ordination plot for the first two CCA dimensions of the relationship between the sedimentary AOA community compositions with the sedimentological and pore-water geochemical parameters in the Changjiang Estuary and adjacent East China Sea before model optimization via manual deselection of collinear variables and automatic forward selection with the Monte Carlo permutation procedure. This plot shows the apparent collinearity of some of the environmental variables. Abbreviations: DIN, dissolved inorganic nitrogen; Kurt, kurtosis; Median, sediment median grain size; Skew, skewness; Sort, sediment sorting coefficient. [ PDF] (231 kb)

PDF

Rarefaction curves of the marine archaeal gene clone libraries constructed with unique RFLP phylotypes (a) or OTUs defined with 95% sequence similarity cutoff (b) using sediment samples from the Changjiang Estuary and the adjacent East China Sea. [ PDF] (231 kb) Principal components analysis of the sedimentary ammonia-oxidizing archaea (AOA) communities with weighted UniFrac using the archaeal AmoA protein sequences recovered from the Changjiang Estuary and adjacent East China Sea. Shown is the plot of the first two principal coordinate axes for PCoA and the distribution of the AOA communities (designated with the sampling station names) in response to these axes. [ PDF] (230 kb) The 'CCA' ordination plot (CCA, canonical correspondence analysis) for the first two CCA dimensions of the relationship between the sedimentary AOA community compositions with the hydrochemical parameters of the surface-water (_S) and bottom-water (_B) environments in the Changjiang Estuary and adjacent East China Sea before model optimization via manual deselection of collinear variables and automatic forward selection with the Monte Carlo permutation procedure. This plot shows the apparent collinearity of some of the environmental variables, such as surface-water salinity, conductivity, density, bottom-water dissolved oxygen and water depth. Surface-water temperature and DO were not included in the analysis due to their diel variations and our sampling time inconsistency for their in situ measurements. Abbreviations: CD, conductivity; DT, water depth; SL, salinity; SG, density; TB, turbidity; TM, temperature. [ PDF] (231 kb) The 'CCA' ordination plot for the first two CCA dimensions of the relationship between the sedimentary AOA community compositions with the sedimentological and pore-water geochemical parameters in the Changjiang Estuary and adjacent East China Sea before model optimization via manual deselection of collinear variables and automatic forward selection with the Monte Carlo permutation procedure. This plot shows the apparent collinearity of some of the environmental variables. Abbreviations: DIN, dissolved inorganic nitrogen; Kurt, kurtosis; Median, sediment median grain size; Skew, skewness; Sort, sediment sorting coefficient. [ PDF] (231 kb)

PDF

Rarefaction curves of the marine archaeal gene clone libraries constructed with unique RFLP phylotypes (a) or OTUs defined with 95% sequence similarity cutoff (b) using sediment samples from the Changjiang Estuary and the adjacent East China Sea. [ PDF] (231 kb) Principal components analysis of the sedimentary ammonia-oxidizing archaea (AOA) communities with weighted UniFrac using the archaeal AmoA protein sequences recovered from the Changjiang Estuary and adjacent East China Sea. Shown is the plot of the first two principal coordinate axes for PCoA and the distribution of the AOA communities (designated with the sampling station names) in response to these axes. [ PDF] (230 kb) The 'CCA' ordination plot (CCA, canonical correspondence analysis) for the first two CCA dimensions of the relationship between the sedimentary AOA community compositions with the hydrochemical parameters of the surface-water (_S) and bottom-water (_B) environments in the Changjiang Estuary and adjacent East China Sea before model optimization via manual deselection of collinear variables and automatic forward selection with the Monte Carlo permutation procedure. This plot shows the apparent collinearity of some of the environmental variables, such as surface-water salinity, conductivity, density, bottom-water dissolved oxygen and water depth. Surface-water temperature and DO were not included in the analysis due to their diel variations and our sampling time inconsistency for their in situ measurements. Abbreviations: CD, conductivity; DT, water depth; SL, salinity; SG, density; TB, turbidity; TM, temperature. [ PDF] (231 kb) The 'CCA' ordination plot for the first two CCA dimensions of the relationship between the sedimentary AOA community compositions with the sedimentological and pore-water geochemical parameters in the Changjiang Estuary and adjacent East China Sea before model optimization via manual deselection of collinear variables and automatic forward selection with the Monte Carlo permutation procedure. This plot shows the apparent collinearity of some of the environmental variables. Abbreviations: DIN, dissolved inorganic nitrogen; Kurt, kurtosis; Median, sediment median grain size; Skew, skewness; Sort, sediment sorting coefficient. [ PDF] (231 kb)

PDF

Rarefaction curves of the marine archaeal gene clone libraries constructed with unique RFLP phylotypes (a) or OTUs defined with 95% sequence similarity cutoff (b) using sediment samples from the Changjiang Estuary and the adjacent East China Sea. [ PDF] (231 kb) Principal components analysis of the sedimentary ammonia-oxidizing archaea (AOA) communities with weighted UniFrac using the archaeal AmoA protein sequences recovered from the Changjiang Estuary and adjacent East China Sea. Shown is the plot of the first two principal coordinate axes for PCoA and the distribution of the AOA communities (designated with the sampling station names) in response to these axes. [ PDF] (230 kb) The 'CCA' ordination plot (CCA, canonical correspondence analysis) for the first two CCA dimensions of the relationship between the sedimentary AOA community compositions with the hydrochemical parameters of the surface-water (_S) and bottom-water (_B) environments in the Changjiang Estuary and adjacent East China Sea before model optimization via manual deselection of collinear variables and automatic forward selection with the Monte Carlo permutation procedure. This plot shows the apparent collinearity of some of the environmental variables, such as surface-water salinity, conductivity, density, bottom-water dissolved oxygen and water depth. Surface-water temperature and DO were not included in the analysis due to their diel variations and our sampling time inconsistency for their in situ measurements. Abbreviations: CD, conductivity; DT, water depth; SL, salinity; SG, density; TB, turbidity; TM, temperature. [ PDF] (231 kb) The 'CCA' ordination plot for the first two CCA dimensions of the relationship between the sedimentary AOA community compositions with the sedimentological and pore-water geochemical parameters in the Changjiang Estuary and adjacent East China Sea before model optimization via manual deselection of collinear variables and automatic forward selection with the Monte Carlo permutation procedure. This plot shows the apparent collinearity of some of the environmental variables. Abbreviations: DIN, dissolved inorganic nitrogen; Kurt, kurtosis; Median, sediment median grain size; Skew, skewness; Sort, sediment sorting coefficient. [ PDF] (231 kb)

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