SScience Journal of Environmental Engineering
Volume 2013, April 2013
© Author(s) 2013. This work is distributed under the Creative Commons Attribution 3.0 License.
Land Use Changes and Their Impacts on the Vegetation Kromme River Peat Basin, South Africa
C. A. Nsor1 and J. Gambiza2
1ąC/O Mesuna Sualihu, Deliman Oil Company, Box 6871, Accra-North, Ghana.
2Department of Environmental Science, Rhodes University, Grahamstown 6140, South Africa
Accepted 21 March, 2013; Available Online 28 April 2013
This study examined plant diversity status and the impact of drivers of change on the Kromme Peatlands in 2006. Species diversity was assessed using Whittaker plots. Ordination techniques were applied to determine species-environment relationship. Land use dynamics were assessed using GIS techniques on orthorectified images. Six peat basins were subjectively classified into good, medium and poor condition peat classes. This classification was based on the extent of disturbance on the vegetation. In the good peat basin (Krugersland), the vegetation was mostly diverse (4.1 Shannon's mean index) followed by medium class (Kammiesbos) (3.8 Shannon mean index) and poor class (Companjesdrift) (2.5 Shannon mean index). Species were not evenly distributed, since 77.8% of the Shannon's evenness index was < 1. There were variations in species richness. Species distribution and composition were influenced by grazing intensity, alien invasive, K, P and Ca2 Total species variance accounted for first two axes was 40.7%. Analysis of images showed a progressive decrease in Peatland between 1942 (5.3%) and 1969 (8.3%) in the good and poor classes, with marginal increase from 1969 (1.5%) to 2003 (4.1%). Annual net rate of change over 61 years was -0.32% and -0.79% respectively. Invasive species in Peatlands increased by 50% between 1942 and 2003. Yearly net rate of change was +0.82% (good class) and +1.63% (poor class). Conservation measures such as clearing of alien invasive species, grazing regulation, construction of gabions (to in improve ground water infiltration, uplifting water table, as well as mitigate the extent of damage caused by floods) in 2003, helped reclaimed large parts of the peat basin that were lost. The continuous implementation of these conservation measures, could greatly improve on the functional status of the peat basin, especially as a carbon sink.
Keywords:Peat lands, species richness, diversity, condition class, species invasion, CCA, Cluster analysis