Atmospheric dinitrogen fixation by benthic communities of Tikehau Lagoon (Tuamotu Archipelago, French Polynesia) and its contribution to benthic primary production

Abstract. One of the major features of the coastal zone is that part of its sea floor receives a significant amount of sunlight and can therefore sustain benthic primary production by seagrasses, macroalgae, microphytobenthos and corals. However, the contribution of benthic communities to the primary production of the global coastal ocean is not known, partly because the surface area where benthic primary production can proceed is poorly quantified. Here, we use a new analysis of satellite (SeaWiFS) data collected between 1998 and 2003 to estimate, for the first time at a nearly global scale, the irradiance reaching the bottom of the coastal ocean. The following cumulative functions provide the percentage of the surface of the coastal zone receiving an irradiance greater than Ez: PaNon-polar=28.80−16.69 log10(Ez)+0.84 log102(Ez)+0.83 log103(Ez) PaArctic=16.01−15.67 log10(Ez)+2.03 log102(Ez)+1.00 log103(Ez) Data on the constraint of light availability on the major benthic primary producers and net primary production are reviewed. Some photosynthetic organisms can grow deeper than the nominal bottom limit of the coastal ocean (200 m). The minimum irradiance required varies from 0.4 to 5.1 mol photons m−2 d−1 depending on the group considered. The daily compensation irradiance of benthic communities ranges from 0.24 to 4.4 mol photons m−2 d−1. Data on benthic irradiance and light requirements are combined to estimate the surface area of the coastal ocean where (1) light does not limit the distribution of primary producers and (2) net community production (NCP, the balance between gross primary production and respiration) is positive. Positive benthic NCP can occur over 37% of the global shelf area. The limitations of this approach, related to the spatial resolution of the satellite data, the parameterization used to convert reflectance data to irradiance, and the relatively limited biological information available, are discussed.

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Light availability in the coastal ocean: impact on the distribution of benthic photosynthetic organisms and their contribution to primary production

Biogeosciences ◽

10.5194/bg-3-489-2006 ◽

2006 ◽

Vol 3 (4) ◽

pp. 489-513 ◽

Cited By ~ 139

Author(s):

J.-P. Gattuso ◽

B. Gentili ◽

C. M. Duarte ◽

J. A. Kleypas ◽

J. J. Middelburg ◽

...

Keyword(s):

Primary Production ◽

Surface Area ◽

Coastal Zone ◽

Benthic Communities ◽

Light Availability ◽

Coastal Ocean ◽

Net Community Production ◽

Benthic Primary Production ◽

Photosynthetic Organisms ◽

Community Production

Abstract. One of the major features of the coastal zone is that part of its sea floor receives a significant amount of sunlight and can therefore sustain benthic primary production by seagrasses, macroalgae, microphytobenthos and corals. However, the contribution of benthic communities to the primary production of the global coastal ocean is not known, partly because the surface area where benthic primary production can proceed is poorly quantified. Here, we use a new analysis of satellite (SeaWiFS) data collected between 1998 and 2003 to estimate, for the first time at a nearly global scale, the irradiance reaching the bottom of the coastal ocean. The following cumulative functions provide the percentage of the surface (S) of the coastal zone receiving an irradiance greater than Ez (in mol photons m−2 d−1): SNon-polar = 29.61 − 17.92 log10(Ez) + 0.72 log102(Ez) + 0.90 log103(Ez) SArctic = 15.99 − 13.56 log10(Ez) + 1.49 log102(Ez) + 0.70 log103(Ez) Data on the constraint of light availability on the major benthic primary producers and net community production are reviewed. Some photosynthetic organisms can grow deeper than the nominal bottom limit of the coastal ocean (200 m). The minimum irradiance required varies from 0.4 to 5.1 mol photons m−2 d−1 depending on the group considered. The daily compensation irradiance of benthic communities ranges from 0.24 to 4.4 mol photons m−2 d−1. Data on benthic irradiance and light requirements are combined to estimate the surface area of the coastal ocean where (1) light does not limit the distribution of primary producers and (2) net community production (NCP, the balance between gross primary production and community respiration) is positive. Positive benthic NCP can occur over 33% of the global shelf area. The limitations of this approach, related to the spatial resolution of the satellite data, the parameterization used to convert reflectance data to irradiance, the lack of global information on the benthic nepheloid layer, and the relatively limited biological information available, are discussed.

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Dinitrogen fixation by exposed communities on the rim of Tikehau atoll (Tuamotu Archipelago, French Polynesia)

Coral Reefs ◽

10.1007/s00338-005-0037-x ◽

2005 ◽

Vol 24 (4) ◽

pp. 622-628 ◽

Cited By ~ 15

Author(s):

C. Charpy-Roubaud ◽

A. W. D. Larkum

Keyword(s):

French Polynesia ◽

Dinitrogen Fixation ◽

Tuamotu Archipelago

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Primary Production and Respiration in Pelagic and Benthic Communities at Two Intertidal Sites in the Upper Bay of Fundy

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f83-286 ◽

1983 ◽

Vol 40 (S1) ◽

pp. s229-s243 ◽

Cited By ~ 51

Author(s):

B. T. Hargrave ◽

N. J. Prouse ◽

G. A. Phillips ◽

P. A. Neame

Keyword(s):

Primary Production ◽

Benthic Communities ◽

Late Summer ◽

Benthic Microalgae ◽

Phytoplankton Production ◽

Bay Of Fundy ◽

Intertidal Sediments ◽

Benthic Primary Production ◽

Benthic Respiration ◽

Undisturbed Sediments

Primary production by microalgae on intertidal sediments during ebb tide at two sites in Cumberland and Minas Basin, Bay of Fundy, amounted to 47–83 g C∙m−2∙yr−1 Phytoplankton production measured during flood tide over intertidal sediments in Cumberland Basin varied from 4–10 g C∙m−2∙yr−1 with respiration in the water column between 6 and 12 g∙C∙m−2∙yr−1 depending on concentrations of suspended matter. Respiration by undisturbed sediments (47–62 g C∙m−2∙yr−1) was measured at both locations to estimate aerobic metabolic consumption of organic matter.Maximum rates of benthic primary production occurred during early and late summer at both locations but Values at the Cumberland Basin sites were two to three times greater than those observed in Minas Basin; Chlorophyll a in surface sediments was also lower at the stations in Minas Basin where coarser grained deposits reflect extensive sediment transport. Annual benthic respiration at the two stations in Cumberland Basin, however, was only slightly greater than that at four stations in Minas Basin. Spartina marshes, phytoplankton, and benthic microalgae may provide supplies of organic matter for aerobic consumption in these intertidal sediments which are more similar than are measures of benthic primary production.Key words: benthic microalgae, primary production, intertidal community metabolism, Bay of Fundy

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A model of the relationship between light and primary production in an atoll lagoon

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400035463 ◽

1990 ◽

Vol 70 (2) ◽

pp. 357-369 ◽

Cited By ~ 9

Author(s):

Loïc Charpy ◽

Claude Julia Roubaud-Charpy

Keyword(s):

Linear Regression ◽

Primary Production ◽

French Polynesia ◽

Light Energy ◽

Linear Regression Models ◽

Benthic Primary Production ◽

Atoll Lagoon ◽

Growth Production ◽

Different Depths ◽

The Relationship

The Tikehau atoll (Tuamoru Archipelago, French Polynesia) is located at 14°S 148°W. Phytoplankton and sand microalgae are the most important primary producers of the lagoon. They were studied for 4 years.The relationship between light energy and lagoonal primary production was measured by using the 14C method for phytoplankton and O2 method for phytobenthos. Incubations, carried out in situ, were made at different depths and light exposition times.Irradiance was high and 17% of the light energy measured at the surface reached 25 m (lagoon average depth). Maxima of phytoplankton and phytobenthos productions occurred at low depths; there was therefore no photoinhibition of photosynthesis. Correlations between light energy and primary production were strong, especially for phytobenthos. Multiplicative linear regression models (production vs light) associated with an exponential linear regression model (light vs depth), allowed planktonic and benthic primary production to be predicted from the depth and the light energy received at the surface. The benthic primary production exceeded the phytoplanktonic production in the upper 18 m. The total primary production (benthos + plankton) was constant with depth and depended only on light energy at the surface. One Einstein received at the lagoon surface allowed the growth production of 14 mg of carbon (water column + sediments).

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Tropical zooplankton in the highly-enclosed lagoon of Taiaro Atoll (Tuamotu Archipelago, French Polynesia)

Coral Reefs ◽

10.1007/s003380050090 ◽

1998 ◽

Vol 17 (1) ◽

pp. 29-35 ◽

Cited By ~ 11

Author(s):

J. H. Carleton ◽

P. J. Doherty

Keyword(s):

French Polynesia ◽

Tropical Zooplankton ◽

Tuamotu Archipelago

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Glacial melt disturbance shifts community metabolism of an Antarctic seafloor ecosystem from net autotrophy to heterotrophy

Communications Biology ◽

10.1038/s42003-021-01673-6 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Ulrike Braeckman ◽

Francesca Pasotti ◽

Ralf Hoffmann ◽

Susana Vázquez ◽

Angela Wulff ◽

...

Keyword(s):

Carbon Balance ◽

Benthic Communities ◽

Benthic Primary Production ◽

Community Metabolism ◽

West Antarctic ◽

Run Off ◽

Net Heterotrophy ◽

Benthic Ecosystems ◽

The Antarctic

AbstractClimate change-induced glacial melt affects benthic ecosystems along the West Antarctic Peninsula, but current understanding of the effects on benthic primary production and respiration is limited. Here we demonstrate with a series of in situ community metabolism measurements that climate-related glacial melt disturbance shifts benthic communities from net autotrophy to heterotrophy. With little glacial melt disturbance (during cold El Niño spring 2015), clear waters enabled high benthic microalgal production, resulting in net autotrophic benthic communities. In contrast, water column turbidity caused by increased glacial melt run-off (summer 2015 and warm La Niña spring 2016) limited benthic microalgal production and turned the benthic communities net heterotrophic. Ongoing accelerations in glacial melt and run-off may steer shallow Antarctic seafloor ecosystems towards net heterotrophy, altering the metabolic balance of benthic communities and potentially impacting the carbon balance and food webs at the Antarctic seafloor.

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