Preliminary evidence on the interdependent effect of currents and porewater geochemistry on Thalassia testudinum Banks ex Konig seedlings

Currents and the chemistry of the porewater may have acted interdependently on the growth and development of Thalassia testudinum seedlings planted in sandy sediments and exposed to stagnant, medium and high current velocities under laboratory-controlled conditions. The most favorable growth conditions (identified by the highest biomass, largest blade area) tended to occur at the intermediate flow rates. Stagnant and high flows may have contributed to lower biomass through increased sulfide levels and reduced nutrient concentrations in the porewater, respectively. These preliminary data suggest that co-varying porewater chemistry may have to be taken into consideration when studying the effect of currents on seagrasses. (C) 1999 Elsevier Science B.V. All rights reserved.