Beschreibung:
Sea-level rise is an important factor in the initation and vertical growth of coastal wetlands. In some areas, however, rapid subsidence of deltaic plain enviroments already translates into major areal losses of ecologically and commerically important wetland. Elsewhere, attention is being focused upon the increased rates sediment accumulation required to maintain wetland elevation and areas against near-future eustatic rise associated with global climatic change. Althrough recently revised downwards, these predictions still envisage a significant acceleration of contemporary eustatic sea-level trends and may induce sedimentary deficits within a wider range of presently stable coastal wetlands. Tide-dominated, predominantly inorganic, salt marshes are particularly important within a European context. Many sites are well documented in respect to local rates of sedimentation, although the methodological basis for quantifying their role as sediment sinks, or identifying accretionary deficits, remains only partially established. Examination of European marsh accretion data indicates a more complex relation between accretion, tidal range and sea-level rise than is suggested by recent syntheses of North American data. Some of this complexity arises because inorganic sedimentation is strongly age- and elevation-dependent. Within-marsh spatial variability is also important and is poorly respresented by crude averaging of point measurements. Preliminary mass balance modelling provides conceptual insights into modes of marsh adjustment to accelerated sea-level rise. Future research must address the need to incorporate state-of-the-art understanding of physical and biological processes into more sophisticated spatial simulations of wetland geomorphic and ecological response to specified environmental forcing.