Vegetation change and chemical soil composition after 4 years of goat grazing exclusion in a Canary Islands pasture

Extensive goat production systems have played an important role in the structure and specific composition of Tenerife's pastures. Due to the steady decline of grazing goats in the Island, the study of the impact of removal of goat grazing on plant communities is of primary importance, in order to delineate a proper conservation strategy for these ecosystems. We analysed changes in floristic composition, species richness, diversity and soil chemical properties of this plant community during 4 years of removal of goat grazing. No changes in species richness or diversity were detected during the study period, but a species turnover was noted in response to absence of goat grazing, related to soil magnesium content. Although this study showed little changes in Tenerife's pastures after 4 years of removal of goat grazing, changes on this community are expected due to soil chemical properties modification in response to absence of goat grazing. it is suggested that a longer period of exclusion will be necessary to detect changes in plant species composition, and additional studies are necessary to develop a suitable pasture management strategy in order to maintain the stability of these ecosystems. (C) 2009 Elsevier B.V. All rights reserved.