Effects of goat pastoralism on ecosystem carbon storage in semiarid thicket, Eastern Cape, South Africa
Article first published online: 10 OCT 2005
Volume 30, Issue 7, pages 797–804, November 2005
How to Cite
MILLS, A. J., COWLING, R. M., FEY, M. V., KERLEY, G. I. H., DONALDSON, J. S., LECHMERE-OERTEL, R. G., SIGWELA, A. M., SKOWNO, A. L. and RUNDEL, P. (2005), Effects of goat pastoralism on ecosystem carbon storage in semiarid thicket, Eastern Cape, South Africa. Austral Ecology, 30: 797–804. doi: 10.1111/j.1442-9993.2005.01523.x
- Issue published online: 10 OCT 2005
- Article first published online: 10 OCT 2005
- Accepted for publication May 2005.
- carbon stocks;
- soil carbon;
Abstract Intensive pastoralism with goats transforms semiarid thicket in the Eastern Cape, South Africa from a dense vegetation of tall shrubs to an open landscape dominated by ephemeral grasses and forbs. Approx. 800 000 ha of thicket (which prior to the introduction of goats had a closed canopy and a Portulacaria afra Jacq. component) have been transformed in this manner. Ecosystem C storage in intact thicket and loss of C due to transformation were quantified. Carbon storage in intact thicket was surprisingly high for a semiarid region, with an average of 76 t C ha−1 in living biomass and surface litter and 133 t C ha−1 in soils to a depth of 30 cm. Exceptional C accumulation in thicket may be a result of P. afra dominance. This succulent shrub switches between C3 and CAM photosynthesis, produces large quantities of leaf litter (approx. 450 g m−2 year−1) and shades the soil densely. Transformed thicket had approx. 35% less soil C to a depth of 10 cm and approx. 75% less biomass C than intact thicket. Restoration of transformed thicket landscapes could consequently recoup more than 80 t C ha−1.