Scale-Dependent Recolonization: The Role of Sediment Stability in a Dynamic Sandflat Habitat

摘要: An important ecological issue is developing an understanding of how patterns and processes vary with scale. We designed a field experiment to test differences in the aerial extent disturbance affected macrofaunal recolonization on sandflat. Three different plot sizes (0.203 m 2 , 0.81 3.24 ) were defaunated, samples collected assess recovery over 9-mo period. As sandflat used for was prone by wind-driven waves, we also measured changes sediment bed height (an indicator stability) course experiment. Most common species revealed significant relationships between density size. Scale-dependent demonstrated assemblage structure Relative rates colonization varied 50% large small experimental plots. However, these not related specific species, particular functional groups, or potential modes colonization. The results unusually slow rate faunal following defaunation. Both increasing numbers colonists ambient sediments made contribution recovery. relationship found wind velocity indicated that wave factor influencing instability. Sediment instability higher all plots than sediments, due initial removal dense spionid polychaete tube mat characteristically at study site. increased Thus this dynamic habitat, emigration from recovering disturbed patches may significantly recolonization. These demonstrate incorporating patch size, emigration, time, interactions hydrodynamic conditions habitat stability (particularly where influence are crucial generating general soft-sediment habitats. While our need caution scaling-up small-scale studies, they do indicate larger scale disturbances destroy organisms role maintaining likely result very dynamics, particularly wave-disturbed