Experimental sediment disturbances on a tidal flat: Responses of free-living Platyhelminthes and small Polychaeta |
| |
Authors: | Karsten Reise |
| |
Affiliation: | (1) Biologische Anstalt Helgoland, Litoralstation, D-2282 List, Federal Republic of Germany;(2) Zoologisches Institut der Universität Göttingen, D-3400 Göttingen, Federal Republic of Germany |
| |
Abstract: | Small-scale sediment disturbances on a sandy tidal flat in the North Sea changed the pattern of abundances in free-living platyhelminths (Turbellaria) and small Polychaeta, but not the species composition. Patches of 0.25 m2 were made anoxic, were regularly raked at the surface, or the upper layer of sediment was inverted. Recolonization after temporary anoxia proceeded very slowly. Raking caused diatom-feeding platyhelminths and the polychaetes to emigrate. Turning the upper 5 cm of the sediment upside down was harmful to both taxa, but platyhelminths recolonized quickly. Background densities were temporarily surpassed, first by predators, then by diatom feeders. Coherent responses of trophic guilds in platyhelminths do not suggest that release from competition is involved but indicate that such disturbances alter the availability of food resources and the organisms immigrate accordingly. |
| |
Keywords: | meiofauna Wadden Sea sand flat disturbance recolonization Turbellaria Polychaeta |
本文献已被 SpringerLink 等数据库收录! |
|