Impacts of clay excavation on the local flora of salt marshes

Abstract

Within the scope of a monitoring project studying the re-colonization of a refilling clay pit after abandonment, composition and development of the salt marsh flora have been investigated. The restoration process has been evaluated by using the species pool concept. Two main effects of clay excavation on the phytodiversity of the study area can be noticed. At the clay pit fringe the number of glycophytes not belonging to the local species pool but the regional pool, increased temporarily within the community pool (disturbance effect for few years). In the core clay pit the recolonisation by species of the local pool is a long lasting process, the return of all species of the local pool within the community pool will need several decades. However, the absence ofLimonium vulgare in the old core clay pit indicates that not all species of the local pool will be able to re-establish in the core area of refilling clay pits within a few decades.