G. M., Ogendi*1,2, T.W. Njoroge1, S. M.Morara1 and R. N. Ondieki2
1Department of Environmental Science, Egerton University, Box 536 Egerton
2Dryland Research Training & Ecotourism Centre, Chemeron, Box 536 Egerton
Studies on invasive plant species have gained prominence owing to their potential to significantly alter plant species community composition and structure thereby negatively impacting on ecosystem services. The effects may include a reduction in the abundance of palatable plant species that constitute important forage for livestock, and medicines for the local communities. The aim of this study was to assess the impacts of copper leaf (Acalypha fruticosa) on plant species diversity and abundance at Chemeron, Baringo County in Kenya. Two sites (one with A. fruticosa and the other without this invasive species) were selected within the Chemeron Research Centre. Two transects measuring 100m X 20m on each site were laid parallel to each other. Plant samples were collected from five 1m X 1m quadrats that were laid at intervals of 20m. The plant samples were identified to the species level using available taxonomic keys. Various indices including Shannon-Wiener (H′), Evenness Index, Richness Index and Simpson’s Index of Diversity Index (1-D) were calculated. All the diversity, richness and evenness indices were considerably higher in the site without A. fruticosa compared to that where this invasive species was present. The H′ and D ranged from 2.34 to 3.28, and 0.87 to 0.94 in site without and with A. fruticosa, respectively. Out of the 47 plant species identified, 37 and 18 of them occurred in the in site without and with A. fruticosa, respectively. The plants were also evenly distributed in the site without A. fruticosa compared to that with the invasive plant present. We conclude that A. fruticosa has a significant influence on plant species abundance and diversity as well as distribution. We therefore recommend to the pastoralists and rangeland managers that copper leaf be removed from grazing lands to stimulate the growth of palatable plant species that support livestock production.
Keywords: Baringo, Copper leaf, Plant Diversity, Diversity Indices, Invasive Species