Examination of multiple disturbances effects on herbaceous vegetation communities in the Sudanian savanna-woodland of West Africa

The results indicate that disturbance regimes, independently or interactively, influenced species abundance over time with inter-site specificity. The dynamics of these disturbance regimes exhibited temporal variation which could be related, to some extent, to inter-annual variation in annual rainfall. The PRC ordination accounted for 38% and 34% of the variation within the data set for sites with deep and shallow soils, respectively. At the site with deep soils, more than one PRC axis was needed to summarize the community response sufficiently, suggesting that the species reacted in different ways to disturbances. The PRC method approach to the analysis of disturbance dynamics allowed us to distil the complexity of the community responses to those of individual species and to identify species that can serve as indicators of certain disturbance regimes.