Conservation of Erica ciliaris and Erica tetralix Communities: The Role of Land Management and Physical Environment on the Composition, Species Richness and Presence of Endemic Taxa

摘要

In spite of their great ecological, economic and social importance, wetlands of all the continents present common problems of insularity, increased by fragmentation due to human action. Between the types of wetlands, some of the more widespread are the wet heathlands that, in the case of Europe, are dominated by Erica ciliaris and Erica tetralix. In this paper, we analysed the species composition of Erica ciliaris and Erica tetralix communities and their relationship to the patch area, as well as the effect of different environmental factors and management. We obtained data of altitude, water-logging degree, area and perimeter, and management type of 30 different sites. Species distribution and species abundance were calculated and the endemic and protected species were identified. We found that the species richness of these communities is related to the distance to the nearest patch and not related to its total area or shape and neither were the number and abundance of the specialist and generalist species, which could be due to the "extinction debt". We also found that the species composition is influenced by both the degree of water-logging and the management of the site, as cutting prevents these communities from advancing to the woodland stage. These two parameters are therefore of great importance for the conservation of wet heathlands.