Impediments to forest recovery in bracken-dominated clearings in the African Highlands

Abstract

Vegetation dynamics in disturbed forested landscapes remain incompletely understood. Considerable areas with stalled forest recovery occur worldwide and may reflect the effects of dense and persistent understorey plants including bracken fern Pteridium aquilinum (L.) Kuhn. Bracken is a long-lived clonal plant which can form monodominant stands that may affect tree seedling establishment. In the East African Highlands persistent bracken thickets already cover hundreds of square kilometres and are associated with failed forest recovery. Studies elsewhere, most of them from temperate and neotropical regions, have suggested various interference mechanisms and it is unclear which are involved in tropical Africa. This thesis consists of a series of studies from a tropical montane forest in Uganda. The main aim of these studies was to examine why forest recovery in bracken-dominated areas is so limited and slow. Such understanding is potentially valuable for forest restoration.