Short-term covariation of dissolved oxygen and phytoplankton photosynthesis in a coastal fish aquaculture site

Abstract The influence of phytoplankton photosynthesis (PP) on dissolved oxygen (DO) dynamics was evaluated in a red sea bream (Pagrus major) aquaculture site. The surface PP was monitored continuously by a natural fluorescence sensor for 2–3 weeks during all seasons, except spring. In summer, when the daily PP was low during cloudy weather, DO at the surface markedly decreased below the critical level (5.7 mg O2 L−1), which is needed for normal fish growth. However, on the subsequent clear day, active PP restored the DO back to above the critical level. In fall, under cloudy skies, the surface DO also decreased below the critical level and remained there, even when the subsequent days were clear. In winter, DO remained at high levels throughout the water column due to an active supply from the air and vertical mixing. Besides seasonal changes, surface DO showed a diel cycle with a minimum early in the morning and maximum in the evening. This diel cycle was also regulated by planktonic photosynthesis. This was most obvious and its amplitude was largest in summer, as PP was very high and thermal stratification prevented diffusion of DO from the surface to deeper water. The present study is the first detailed report on the close coupling of DO with PP in coastal waters, even under non-bloom conditions. Cloudy weather and early mornings were found to be the most critical periods in oxygen supply to cultured fish and other pelagic organisms in a fish culture site and other eutrophic coastal area.

[1]  W. Broecker,et al.  Gas Exchange-Wind Speed Relation Measured with Sulfur Hexafluoride on a Lake , 1985, Science.

[2]  B. García,et al.  Oxygen consumption and ventilatory frequency responses to gradual hypoxia in common dentex (Dentex dentex): Basis for suitable oxygen level estimations , 2006 .

[3]  C. Taylor,et al.  Effect of sampling frequency on measurements of seasonal primary production and oxygen status in near-shore coastal ecosystems , 1994 .

[4]  J. Talling.  PHOTOSYNTHETIC CHARACTERISTICS OF SOME FRESHWATER PLANKTON DIATOMS IN RELATION TO UNDERWATER RADIATION , 1957 .

[5]  William H. Neill,et al.  Effects of water temperature and dissolved oxygen on daily feed consumption, feed utilization and growth of channel catfish (Ictalurus punctatus) , 2000 .

[6]  A. Sévère,et al.  Effects of hypoxia on growth and metabolism of juvenile turbot , 2000 .

[7]  Motoaki Kishino,et al.  Estimation of the spectral absorption coefficients of phytoplankton in the sea , 1985 .

[8]  K. Furuya,et al.  Long-term monitoring of primary production in coastal waters by an improved natural fluorescence method , 2004 .

[9]  J. Strickland.  A practical hand-book of seawater analysis , 1972 .

[10]  J. Erez,et al.  Daily oxygen variations in marine fish ponds, Elat, Israel , 1990 .

[11]  Y. Yi,et al.  Effects of biomass of caged Nile tilapia (Oreochromis niloticus) and aeration on the growth and yields in an integrated cage-cum-pond system , 2001 .

[12]  H. S. Lee,et al.  Continuous monitoring of short term dissolved oxygen and algal dynamics , 1995 .

[13]  Takashi Ishimaru,et al.  An improved method for the determination of phytoplankton chlorophyll using N, N-dimethylformamide , 1990 .

[14]  A. Weidemann,et al.  Quantifying absorption by aquatic particles: A multiple scattering correction for glass-fiber filters , 1993 .

[15]  D. Breitburg,et al.  Covariability of dissolved oxygen with physical processes in the summertime Chesapeake Bay , 1990 .

[16]  A. Stigebrandt.  Computations of oxygen fluxes through the sea surface and the net production of organic matter with application to the Baltic and adjacent seas , 1991 .

[17]  M. Takahashi,et al.  Measurement of photosynthetic production of a marine phytoplankton population using a stable 13C isotope , 1983 .

[18]  T. Parsons,et al.  A practical handbook of seawater analysis , 1968 .

[19]  H. Odum.  Primary Production in Flowing Waters1 , 1956 .

[20]  P. Williams,et al.  Overall planktonic oxygen and carbon dioxide metabolisms: the problem of reconciling observations and calculations of photosynthetic quotients , 1991 .

[21]  R. Piedrahita,et al.  Diel cycles of planktonic respiration rates in briefly incubated water samples from a fertile earthen pond , 1992 .

[22]  J. H. Morrow,et al.  Evidence for a simple relationship between natural fluorescence, photosynthesis and chlorophyll in the sea , 1990 .

[23]  Michael R. Roman,et al.  Effects of low oxygen waters on Chesapeake Bay zooplankton , 1993 .

[24]  A. Morel,et al.  An incubator designed for extensive and sensitive measurements of phytoplankton photosynthetic parameters , 1994 .

[25]  Dale A. Kiefer,et al.  Natural fluorescence of chlorophyll a: Relationship to photosynthesis and chlorophyll concentration in the western South Pacific gyre , 1989 .

[26]  Trevor Platt,et al.  Mathematical formulation of the relationship between photosynthesis and light for phytoplankton , 1976 .

[27]  H. Yokoyama.  Environmental quality criteria for fish farms in Japan , 2003 .

[28]  Aaron T. Adamack,et al.  The pattern and influence of low dissolved oxygen in the Patuxent River, a seasonally hypoxic estuary , 2003 .

[29]  Rozangela Curi Pedrosa,et al.  Effect of different oxygen tensions on weight gain, feed conversion, and antioxidant status in piapara, Leporinus elongatus (Valenciennes, 1847) , 2005 .

[30]  John C. Davis.  Minimal Dissolved Oxygen Requirements of Aquatic Life with Emphasis on Canadian Species: a Review , 1975 .

[31]  P. Buat-Ménard.  The role of air-sea exchange in geochemical cycling , 1986 .

[32]  R. J. Gowen,et al.  The ecological impact of salmonid farming in coastal waters: a review , 1987 .

[33]  K. Furuya,et al.  Effects of diurnal variations in phytoplankton photosynthesis obtained from natural fluorescence , 2006 .