Effect of soil type on herbaceous species composition and distribution in community property association projects of Bela-Bela municipality, South Africa

Abstract

Information on species composition and distribution is vital in assessing rangeland condition and mitigating its deterioration in Community Property Associations (CPAs) projects. Herbaceous vegetation composition, biomass and basal cover was compared in three CPAs projects varying in soil type and grazing pressure (Mashung Matlala-sandy loam, Mawela-clay loam, and Bela-Bela-clay) in Bela-Bela municipality. Mawela and Mashung Matlala were severely grazed. Two camps were selected per farm and three transects (500m) were used to collect data on species composition, distribution, biomass and basal cover. Species were grouped according to life form, palatability, ecological status and abundance. Variation in measured parameters was explored through a GLM analysis of variance procedure of SAS. Clay soil had higher levels (P < 0.05) of nutrients compared to sandy and clay loam. Panicum maximum was common in clay-loam and clay soil and dominant in sandy-loam. Eragrostis curvula and Urochloa mosambicensis were dominant in clay-loam and common in clay soil. Clay soil had the highest (P < 0.05) biomass (711.84 kg/ha) compared to the other two. Clay soil had higher (P < 0.05) basal cover (38.0%), and sandy-loam had the highest (P < 0.05) percentage of forbs (6.4%). There is an invasion of forbs and pioneer grasses in heavily grazed sites of Mashung Matlala and Mawela CPA farms, which adversely impact livestock production. Grazing management intervention should be guided by information on species composition and biomass, which reflects past management, and variation in soil type. Practical grazing plans should aim to reduce pressure on clay and sandy-loam areas.