Variability of primary and bacterial production in a coral reef lagoon (New Caledonia)

We assessed the temporal variability of nutrients, phytoplankton and bactenoplankton at two sites of different trophic status in New Caledonia's South-West lagoon, a tropical coastal ecosystem. During stable meteorological conditions. Chl.a, bacterial production and nutrient concentrations experience weak but consistent daily variation. Short-term (1-2 week interval) fluctuations of planktonic variables are in the same range as annual variations at both sites. A part of these short term variations is linked to local meteorological events (wind in the main channel, precipitation at the coastal station) Although annual vananons are weak compared to short term variations, phytoplankton and bactenoplankton production show consistent temporal patterns, with maxima in December-January and April-May and minima in August. Annual bacterial production represents 21% and 34% of particulate primary production at the ohgotrophic and mesotrophic sites, respectively. Mineral nutrient availability indicates that nitrogen is probably the primary limiting factor of phytoplankton throughout the year (C) 2010 Elsevier Ltd All rights reserved.