Recovery of plant communities on coastal sand-dunes disturbed by human trampling

Abstract

The resilience of plant communities to disturbance can be characterized by the ability of species and life-forms to recover, provided that the desired degree of naturalness is present. Results of a case study in two ecological types of Danish sand dunes, the grey and the white dune, show that dominant growth morphology and initial pattern of recovery are inter-related. The propagation of above-ground organs leads to progressive lateral recovery, while subterranean proliferation by means of rhizomes leads to erratic recovery. Species behave in different ways depending on the environment, and patches of bare ground generally grow over slowly, unlike well-established patches of vegetation where environmental conditions are more suitable. Because of this change of structure, vegetation recovery is not assessable by traditional recording of individual factors such as number of species or percentage cover, and a list of the key factors involved is given. The erratic pattern of recovery of rare species stresses the importance of long-term recording of vegetation to assess recovery.