Plant Diversity Status of the Kromme Peatland, E/Cape, South Africa.

      Аннотация: This study examined the current plant diversity status and the impact of drivers of change on the Kromme River peatland in the Eastern Cape of South Africa. Plant diversity were quantified using Shannon-Weiner index, while the influence of environmental variables was investigated using multivariate techniques. Land use dynamics were assessed by applying GIS techniques. There were variations in species richness across peat basins(p=0.0008, F = 1241.6).Generally, species were not evenly distributed (p>0.21; F = 0.94), since 77.8% of the evenness index were <1. Krugersland was the most diverse (H'=4.1) and species rich (32.5±3.4)and Companjesdrift was the least rich(22.5±8.9).Erosion and grazing intensity, potassium,phosphorus and soil pH influenced species diversity,with the first two axes accounting for 40.7% ground cover and 56.4% plant height variance.Peatland area decreased in between 1942 and 1969 in Krugersland (5.3%) and Companjesdrift (8.3%), with a marginal increase of 1.5% and 4.1% respectively from 1969 to 2003.Annual net rate of change over the 61 year period was -0.32% (Krugersland) and -0.79% (Companjesdrift).Alien species contributed 50% in transforming the peatlands.

Ключевые слова: diversity, Cluster Analysis, CCA, species richness, Peat lands, condition class, species invasion