Herbaceous and Woody Plant Properties in Abandoned Kraal Areas in a Hardveld Botswana

Abstract

Herbaceous and woody plant species in abandoned traditional kraals were investigated. To achieve the aim of this study, nutrient status of soil in addition to vegetation composition and communities from the kraal sites were analyzed and results compared with those from control sites. A total of 25 kraals that had been abandoned between 5 and 45 years were sampled. Data were analyzed using multivariate procedures; a two-way indicator species analysis (TWINSPAN), detrended correspondence analysis (DCA) and canonical correspondence analysis (CCA) to establish classification of the plant communities. The significant environmental variables identified with t-values above 2.1 that determined the composition and patterns of the plant communities were organic matter, plant available nitrogen, calcium and moisture content. The results show major differences in soil physio-chemical properties and also in patterns and composition of vegetation communities between kraals and their surrounding areas. Evidence from the results show that kraal areas play an important role in determining key resource areas by influencing systematic distribution of nutrients. With kraals tending to increase the heterogeneity in the natural distribution of nutrients, it is apparent that animal waste deposited in the kraals modify vegetation patterns as high nutrient tolerant species gain competitive advantage over those that are not. The findings provide some important information that could explain herbaceous and woody species community patterns particularly in semi-arid environments where livestock management by the use of traditional kraals is a common practice.