PRIMARY PRODUCTION AND IMPORT OF PARTICULATE ORGANIC-MATTER ON A SALT-MARSH IN THE NETHERLANDS

The macrophyte production and the transport of particulate organic matter between marsh and adjacent estuary have been investigated for a 0.3 km2 salt marsh along the Oosterschelde estuary, The Netherlands. The primary production of macrophytes, measured with Smalley's (1959) method was 837 to 1030 g dry organic matter·m-2·y-1. Measurements of amounts of particulate organic matter transported through one of the main tidal creeks in the salt marsh resulted in a net import. On an average 31% of the material brought in by the flood settled in the marsh. The majority of this material is smaller than 63 μm. On the other hand large floating material is exported during storm tides, although the quantity seems to be smaller than that of the suspended material imported. The differences between various marshes with regard to export and import of organic matter are explained in terms of marsh level, primary production, turbulent diffusion, sinking and resuspension of particulate matter and biotic transformations. © 1979.