Sahelian Rangeland Development; A Catastrophe?

This paper sets out that the dynamics of the Sahelian range- vegetation can be interpreted as a cusp catastrophe and that interpretation offers a promising basis for the description analysis of tbis ecosystem. , an existing scheme of the dynamics of Sahelian herbaceous is translated into the state-and-transition formulation. , the application of the cusp catastrophe is by studying the behaviour of the Sahelian rangeland under changing effective rainfall and grazing inteusity, the transitions from the state-and-transition formulation vectors along the cusp manifold. This conceptual cusp catastrophe subsequently results in the identification of and the detection of 5 catastrophic properties of this (biiodality, inaccessibiity, sudden jumps, divergence hysteresis) that have important management implications. continuous and the discontinuous processes occurring in Sahelian rangeland ecosystem can both be captured in a tified model by applying the cusp catastrophe theory. the hypotheses generated by the conceptual model and for additional catastrophic properties, such as divergence linear response and critical slowing down, is a useful direction for future research.