Sediment ammonium availability and eelgrass ( Zostera marina ) growth

摘要: The interaction of sediment ammonium (NH 4 + ) availability and eelgrass (Zostera marina L.) growth, biomass photosynthesis was investigated using controlled environment in-situ manipulations pore water concentrations. Sediment diffusers were used to create diffusion gradients fertilize deplete levels in sediments with intact rhizospheres. Between October, 1982 September, 1983 experiments plants from shallow (1.3 m) deep (5.5 stations a Great Harbor, Woods Hole, Massachusetts, USA meadow along at these provided range concentrations between 0.1 10 mM (adsorbed+interstitial NH ). results the indicate that nitrogen limitation growth does not occur Harbor meadow. A comparison regeneration rates requirements indicates an excess supply over demand provides explanation for lack response manipulations. Results combined suggest pool above approximately 100 μmol per liter (interstitial only) saturate Zostera marina.