Regeneration of an Afromontane forest following gricultural encroachment in southwestern Uganda

A study of the regeneration of an Afromontane forest was carried out in Mga hinga Gorilla National Park (MGNP), southwestern Uganda, following agricult ural encroachment in the last 50 years. The landscape was changed by terrac ing and removing the indigenous vegetation and replacing it with exotic tre e species. This study also examined the soil nutrient status of the formerl y encroached area in the park. Species richness of indigenous trees was high in the formerly cultivated ar ea. Twenty-six indigenous species were found in the formerly cultivated are a, compared with 20 species in the natural forest and 12 species of indigen ous trees found under exotic woodlots. There was a significant difference i n species richness acid density in the three habitat types. The natural for est supported the highest stem density (75%), and the lowest stem density ( 4%) was recorded under exotic woodlots. Seedlings (<2 cm diameter at breast height) accounted for the majority of juveniles in the three habitats. The natural forest had the highest density (24,625 seedlings/ha), and exotic w oodlots supported the lowest stem density (1,350 seedlings/ha). The level of regeneration in the formerly encroached area is influenced by the intensity of cultivation and soil nutrients. The advanced growth beneat h the exotic woodlots, especially black wattle (Acacin mearnsii) and Eucaly ptus sp. stands, is relatively impoverished. This condition beneath the exo tic species suggests that a low diverse community of native species is able to exploit this environment.