A weighted key species method for monitoring changes in species composition of Highland Sourveld

Abstract

The use of key species for indexing veld condition in relation to the fire/grazing impact has potential for monitoring change in the Highland Sourveld of Natal. Weightings are calculated for previously identified key species. A weighted-averages approach is used in a modified weighted key species method of indexing veld condition. Veld condition indices calculated using the method are highly correlated with rankings along a previously identified grazing gradient (r = 0, 85). Weightings are provided for indicator species that can be generally used for monitoring vegetation changes in the Highland Sourveld. The method has the advantage of being able to determine the position of a sample site on a grazing gradient, and thereby make inferences as to the grazing/burning history of the site.Language: EnglishKeywords: botany; burning; condition indices; grazing gradient; grazing history; highland sourveld; indicator species; key species; method; monitoring; natal; ordination; range condition; Range conditions; south africa; species composition; vegetation change; vegetation changes; veld condition