scholarly journals Sources of primary production, benthic-pelagic coupling, and trophic relationships within the Northeast Water Polynya:insights from delta13C and delta15N analysis

1995 ◽  
Vol 128 ◽  
pp. 1-10 ◽  
Author(s):  
KA Hobson ◽  
WG Ambrose ◽  
P Renaud
Keyword(s):  
Primary Production ◽  
Trophic Relationships ◽  
Benthic Pelagic Coupling

Benthic–pelagic coupling in the Gulf of Mexico hypoxic area: Sedimentary enhancement of hypoxic conditions and near bottom primary production

2014 ◽  
Vol 85 ◽  
pp. 143-152 ◽  
Author(s):  
Clifton C. Nunnally ◽  
Antonietta Quigg ◽  
Steve DiMarco ◽  
Piers Chapman ◽  
Gilbert T. Rowe
Keyword(s):  
Gulf Of Mexico ◽  
Primary Production ◽  
Hypoxic Conditions ◽  
Hypoxic Area ◽  
Benthic Pelagic Coupling

scholarly journals Ballasted Flocs Capture Pelagic Primary Production and Alter the Local Sediment Characteristics in the Coastal German Bight (North Sea)

Geosciences ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 344 ◽  
Author(s):  
Andreas Neumann ◽  
H. Christian Hass ◽  
Jürgen Möbius ◽  
Céline Naderipour
Keyword(s):  
Primary Production ◽  
North Sea ◽  
German Bight ◽  
Settling Velocity ◽  
Coastal Environments ◽  
Sediment Characteristics ◽  
Empirical Correlations ◽  
Extracellular Polymers ◽  
High Turbulence ◽  
Benthic Pelagic Coupling

Suspended, organic matter, especially in the form of adhesive extracellular polymers (EPS), tends to form flocs, which may also incorporate suspended lithogenic particles in coastal environments. With an increased settling velocity, these ballasted flocs form in a narrow zone along the coast and potentially represent a major source of pelagic primary production for the benthic community. We sought support for this hypothesis by examining our measurements of the mud content, porosity, permeability, pigment content, and specific respiration rate of sediment from the German Bight (North Sea) for signs that the pelagic zone of ballasted floc formation is affecting the local sediment characteristics. Based on a simple bottom-shear stress model and by employing empirical correlations of sediment characteristics we were able to find strong indications that this is actually the case. Our results demonstrate how ballasted flocs contribute to the benthic pelagic coupling in a high turbulence environment.

scholarly journals Benthic‐pelagic coupling and trophic relationships in northern Baltic Sea food webs

2020 ◽  
Vol 65 (8) ◽  
pp. 1706-1722 ◽  
Author(s):  
Mikko Kiljunen ◽  
Heikki Peltonen ◽  
Maiju Lehtiniemi ◽  
Laura Uusitalo ◽  
Tuula Sinisalo ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Food Webs ◽  
Trophic Relationships ◽  
Benthic Pelagic Coupling

scholarly journals A model for the benthic-pelagic coupling of silica in estuarine ecosystems: sensitivity analysis and system scale simulation

2007 ◽  
Vol 4 (2) ◽  
pp. 747-796 ◽  
Author(s):  
S. Arndt ◽  
P. Regnier
Keyword(s):  
Sensitivity Analysis ◽  
Primary Production ◽  
Biogenic Silica ◽  
Transport Processes ◽  
Time Lags ◽  
Diffusive Flux ◽  
Diatom Bloom ◽  
Dissolved Silica ◽  
Benthic Pelagic Coupling ◽  
Production Dynamics

Abstract. A transient, vertically resolved, analytical model for the early diagenesis of silica has been developed to quantify the importance of benthic-pelagic coupling in estuarine biogeochemical silica cycling. A sensitivity analysis based on Monte-Carlo simulations is carried out to assess the intensity and timing of benthic diffusive fluxes in response to a pelagic diatom bloom. The diffusive flux dynamics are analyzed over a realistic range of dissolution rate constants (max kSi ε [6×10−3−3.6×10−1 d−1]), diffusion coefficients of dissolved silica (DSi ε [35×10−6−35×10−5 m2 d−1]) and duration of dissolved silica depletion in the water column (wPDSI ε [1–3 month]). Results show that the diffusive silica flux responds with a time delay of 20 to 120 days to the biogenic silica deposition pulse. For high max kSi, simulated time lags are shortest and completely determined by the dissolution kinetics. However, decreasing max kSi leads to a slower benthic flux response. In addition, the variability increases due to the increasing importance of transport processes. The sensitivity study also allows us to constrain the uncertainties of a system-scale simulation, where a large number of benthic compartments (>50 000) are coupled to a high-resolution (100×100 m) pelagic model of a macrotidal river and estuary (Western Scheldt, B/NL). The model is applied to a diatom bloom event recorded in 2003, characterized by pelagic silica depletion in August. Benthic processes are mainly modulated by the combined influence of local hydrodynamic conditions and pelagic primary production dynamics, and show therefore a high degree of spatial heterogeneity over short distances. Spatially integrated deposition fluxes and dissolution rates of biogenic silica are high throughout the growth period, with maxima of 1.3×105 mol d−1 (=8.0 mmol m2 d−1) and 7.8×04 mol d−1 (=4.8 mmol m2 d−1) in mid-August. The spatially integrated diffusive flux reaches a maximum of 1.5×104 mol d−1 at the end of a pelagic silica depletion period in September. However, the total amount of dissolved silica released from the estuarine sediments between June and December 2003 is small (2×106 mol) compared to the much higher riverine influx of dissolved silica (5.9×107 mol) and plays a minor role in the pelagic primary production dynamics.

scholarly journals A model for the benthic-pelagic coupling of silica in estuarine ecosystems: sensitivity analysis and system scale simulation

2007 ◽  
Vol 4 (3) ◽  
pp. 331-352 ◽  
Author(s):  
S. Arndt ◽  
P. Regnier
Keyword(s):  
Sensitivity Analysis ◽  
Primary Production ◽  
Biogenic Silica ◽  
Transport Processes ◽  
Time Lags ◽  
Diffusive Flux ◽  
Diatom Bloom ◽  
Dissolved Silica ◽  
Benthic Pelagic Coupling ◽  
Production Dynamics

Abstract. A transient, vertically resolved, analytical model for the early diagenesis of silica has been developed to quantify the importance of benthic-pelagic coupling in estuarine biogeochemical silica cycling. A sensitivity analysis based on Monte-Carlo simulations is carried out to assess the intensity and timing of benthic diffusive fluxes in response to a pelagic diatom bloom. The diffusive flux dynamics are analyzed over a realistic range of dissolution rate constants (max kSi ε [6×10−3–3.6×10−1 d−1]), diffusion coefficients of dissolved silica (DSi ε [35×10−6–35×10−5 m2 d−1]) and duration of dissolved silica depletion in the water column (wPDSI ε [1–3 month]). Results show that the diffusive silica flux responds with a time delay of 20 to 120 days to the biogenic silica deposition pulse. For high max kSi, simulated time lags are shortest and completely determined by the dissolution kinetics. However, decreasing max kSi leads to a slower benthic flux response. In addition, the variability increases due to the increasing importance of transport processes. The sensitivity study also allows us to constrain the uncertainties of a system-scale simulation, where a large number of benthic compartments (>50 000) are coupled to a high-resolution (100×100 m) pelagic model of a macrotidal river and estuary (Western Scheldt, B/NL). The model is applied to a diatom bloom event recorded in 2003, characterized by pelagic silica depletion in August. Benthic processes are mainly modulated by the combined influence of local hydrodynamic conditions and pelagic primary production dynamics, and show therefore a high degree of spatial heterogeneity over short distances. Spatially integrated deposition fluxes and dissolution rates of biogenic silica are high throughout the growth period, with maxima of 1.3×105 mol d−1 (=8.0 mmol m2 d−1) and 7.8×104 mol d−1 (=4.8 mmol m2 d−1) in mid-August. The spatially integrated diffusive flux reaches a maximum of 1.5×104 mol d−1 at the end of a pelagic silica depletion period in September. However, the total amount of dissolved silica released from the estuarine sediments between June and December 2003 is small (2×106 mol) compared to the much higher riverine influx of dissolved silica (5.9×107 mol) and plays a minor role in the pelagic primary production dynamics.

PRESENT AND FUTURE PROSPECTS FOR FORESTRY IN THE CENTRAL PUMICE REGION

1971 ◽  
pp. 14-17
Author(s):  
J. Ure
Keyword(s):  
New Zealand ◽  
Primary Production ◽  
Future Prospects ◽  
Export Markets ◽  
Local Conditions

The region contains half the area of exotic forest in New Zealand and the major industries dependent thereon. Both are expanding rapidly to meet promising export markets. Local conditions are particularly favourable for this form of primary production and continued expansion is expected.

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