Vertical fluxes of particulate matter in Aarhus Bight, Denmark

Pejrup, Morten; Valeur, Jens Rosendal; Jensen, Annie Aarup

doi:10.1016/0278-4343(95)00044-5

Cited by 32 publications

(16 citation statements)

References 14 publications

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“…The resuspended load declines exponentially with increasing height above the sediment source and can, therefore, be estimated as the intercepts at the sediment surface (i.e., height ϭ 0) of the fitted exponential relationships between the downward depositional flux and the height of the sediment traps above the bottom (Pejrup et al 1996). Three replicated sediment trap arrays (five units each) for the estimation of total deposition at 20 cm height (i.e., a total of 15 replicated sedimentation tubes) and one structure with five units of five sediment traps each, positioned at 20, 40, 60, 80, and 100 cm above the bottom, were assembled by selfcontained underwater breathing apparatus (SCUBA) divers inside the meadow.…”

Section: Methodsmentioning

confidence: 99%

Carbon and nutrient deposition in a Mediterranean seagrass (Posidonia oceanica) meadow

Gacia¹,

Duarte²,

Middelburg³

2002

Limnology & Oceanography

231

157

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The annual depositional flux of carbon (C), nitrogen (N), and phosphorous (P) to the sediments under a northeast Spain Posidonia oceanica meadow was evaluated, and the sources and fate of the material deposited elucidated. The annual deposition of carbon represented 198 g C m Ϫ2 yr Ϫ1, 72% of which was derived from the seston and 28% from P. oceanica detritus. The depositional flux was poor in nitrogen (13.4 g N m Ϫ2 yr Ϫ1 ) and phosphorous (2.01 g P m Ϫ2 yr Ϫ1 ), although comparable to the nutrient inputs required to support the growth of P. oceanica. Remineralization in the sediment only returned 15.6 g C m Ϫ2 yr Ϫ1, yielding a net carbon accumulation of 182 g C m Ϫ2 yr Ϫ1. Our results show that in the Mediterranean littoral P. oceanica meadows are important sites of net organic carbon burial, derived from sedimented sestonic particles and seagrass detritus.

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Section: Methodsmentioning

confidence: 99%

Carbon and nutrient deposition in a Mediterranean seagrass (Posidonia oceanica) meadow

Gacia¹,

Duarte²,

Middelburg³

2002

Limnology & Oceanography

231

157

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“…Aarhus Bay is a 315-km 2 semienclosed embayment on the east coast of Jutland, connected to the Kattegat. The sediment is composed of 20% fine to very fine sand, 22% silt and 55% clay (Pejrup et al 1996). A 4.6-mlong sediment piston core, 7 cm diameter, was collected.…”

Section: Methodsmentioning

confidence: 99%

“…In the laboratory, cores were divided longitudinally, and 50-cm 3 subsamples from 29 different depth zones of the core were taken by disposable syringes with the tips removed. The age of the 4.6-m core was estimated to be a maximum of 2,300 yr, because at the same station, Pejrup et al (1996) were measured by ion chromatography according to Thomsen et al (2001). Cl Ϫ salinity in the upper sediment section (11 cm deep) was assumed to reflect salinity in the overlying seawater and was used as a reference for the deeper sediment layers.…”

Section: Methodsmentioning

confidence: 99%

Bacterial influence on amino acid enantiomerization in a coastal marine sediment

Pedersen

Thomsen

Lomstein

et al. 2001

Limnology & Oceanography

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The contribution of D-isomers of aspartate (Asp), glutamate (Glu), alanine (Ala), and serine (Ser) to the total concentrations of dissolved free amino acids (DFAA), dissolved combined amino acids (DCAA), and total hydrolyzable amino acids (THAA) was studied in a Ͻ2,300-yr-old coastal sediment. Concentrations of the different amino acid pools were typically 5 (DFAA), 100 (DCAA), and 20,000 nmol cm Ϫ3 (THAA), but variable amounts occurred, especially in the surface layer. D-amino acids were identified in all three amino acid fractions. The highest concentration of D-isomers occurred in the THAA fraction at a depth of 10 cm, where the maximum bacterial density has been observed (Jørgensen et al. 1990; Mar. Ecol. Prog. Ser. 59: 39-54). This coincidence suggests that the D-amino acids originated in peptidoglycan of bacterial cell walls. The proportion of D-Asp, D-Glu, D-Ala, and D-Ser increased through the pools of DFAA and DCAA to THAA, suggesting a selective removal of L-amino acids to D-amino acids. The percentage of the four D-amino acids in the THAA pool increased with sediment depth to at least 4.3 m (ϳ2,150 yr). This most likely indicated that peptidoglycan THAA were retained for a longer period of time in a particulate form compared to other proteinaceous material. The contribution of THAA from peptidoglycan to the THAA pool was estimated to range from Ͼ9% at the surface to at least 18% at 4.3 m deep, depending on the assumptions used in the calculation. The distribution of amino acid isomers in Aarhus Bay sediment demonstrated that bacterial peptidoglycan contributed to the pool of organic nitrogen (the four analyzed D-amino acids made up about 3% of particulate organic nitrogen [PON]). Although the peptidoglycan concentration increased with sediment depth, our observations do not indicate a long-term accumulation of peptidoglycan-derived amino acids.

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“…Due to its multiple effects on the ecosystem of lake, there has been increased awareness of the importance of the resuspension process in shallow lakes. In recent years, the influence of sediments resuspension on lake ecological system was studied by significant number of researchers (Michelcic et al, 1996;Pejrup et al, 1996;Rutgers et al, 1997). Special attention was paid to shallow lake, because the sediments of shallow lake were disturbed by wind and the resuspension happened more frequently (Hawley and Lesht, 1992;Søndergaard et al, 1992).…”

Section: Introductionmentioning

confidence: 99%

Morphological characterization of suspended particles under wind-induced disturbance in Taihu Lake, China

Wang

Zhang

et al. 2006

Environ Monit Assess

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Sediments are disturbed by wind frequently, especially in the shallow lakes. The characteristics of resuspended sediment particles in Taihu Lake were studied under different wind velocities. It showed that sediment particles suspended obviously and particle number in overlying water increased directly under high wind-induced disturbance. Suspended solid (SS) concentration was less than 50 mg/l when the wind velocity was below 3.0 m/s, however, it increased to more than 300 mg/l when the wind velocity was 10.0 m/s. Two methods were used to measure the fractal characteristics of particles. One was light scattering and the other was image analysis. The three-dimensional fractal dimensions of suspended particles, measured by light scattering, were between 2.26 and 2.44; correspondingly, the two-dimensional fractal dimensions, calculated by image analysis, were between 1.44 and 1.77. Moreover, the three-dimensional fractal dimensions were directly proportional to two-dimensional fractal dimensions. The characteristic length of particles was calculated by image analysis. The minimum characteristic length was close to 8.5 μm when the wind velocity was 1.5 m/s at 50 cm beneath lake surface, while, the maximum characteristic length was approximate to 24 μm when the wind velocity was 10 m/s at the depth of 150 cm.

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Vertical fluxes of particulate matter in Aarhus Bight, Denmark

Cited by 32 publications

References 14 publications

Carbon and nutrient deposition in a Mediterranean seagrass (Posidonia oceanica) meadow

Carbon and nutrient deposition in a Mediterranean seagrass (Posidonia oceanica) meadow

Bacterial influence on amino acid enantiomerization in a coastal marine sediment

Morphological characterization of suspended particles under wind-induced disturbance in Taihu Lake, China

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