Water renewal time for classification of atoll lagoons in the Tuamotu Archipelago (French Polynesia)
Andrefouet, S.; Pages, J.; Tartinville, B. (2001). Water renewal time for classification of atoll lagoons in the Tuamotu Archipelago (French Polynesia). Coral Reefs 20(4): 399-408. https://dx.doi.org/10.1007/s00338-001-0190-9 In: Coral Reefs. Springer: Berlin; Heidelberg; New York. ISSN 0722-4028; e-ISSN 1432-0975, more | |
Author keywords | lagoon; atoll; hydrodynamics; residence time; phytoplankton; SPOT; |
Authors | | Top | - Andrefouet, S.
- Pages, J.
- Tartinville, B.
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Abstract | The feasibility of using hydrodynamic renewal time as the basis for a classification of atoll lagoons is tested for atolls of the Tuamotu Archipelago, French Polynesia. Renewal time depends on the inflow of oceanic water through the rim of the atoll, on a daily time scale, due to wave forcing. Renewal time is computed for a large set of morphologically diverse atolls, according to significant wave height (satellite altimetry data), morphometric indicators (high-resolution satellite images), and in-situ flow measurements. Renewal times with respect to wave height are presented for a variety of atolls. Renewal times range from less than 1 day for very open and shallow atolls, to several tens of days for semi-open moderately deep atolls, and to several years for closed or very large and deep atolls. Comparisons between phytoplanktonic biomass (in the range 0.1 to 1 µg l-1 for total chlorophyll) and renewal time (0.1 to 130 days) leads to the identification of two groups of atolls. We obtain a significant relationship between biomass and renewal time, but only for atolls with lagoon surface areas greater than 25 km2. |
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