Assessment of the Impacts of Anthropogenic Activities on Woody Plant Diversity in the Woodlands of the Pette Subdivision (Far-North, Cameroon).

Abstract

The land use/land cover in the Sudano-Sahelian area of Cameroon has been disturbed since these 3 decades resulting from the influence of anthropogenic factors. This study aimed to assess floristic diversity and the impacts of anthropogenic activities on the Pette forest massifs in the Pette Subdivision. The transect method (1000 × 20 m) was used for plant inventory, and Landsat images 5 TM (1990), 7 ETM+ (2005) and 8 OLI_TIRS (2020) were analysed to determine land cover. In total, 44 woody species belonging to 30 genera and 20 families were identified. The most frequent species (10.17%) was Grewia bicolor, and the species with high density was Acacia ataxacantha (56.87 stems·ha^-1). The forest massifs were dominated by Anogeissus leiocarpus (36.01%), and the basal area was 234.77 m²·ha^-1. The Shannon diversity index varies from 3.53 to 3.99 bits in Fadare and Tchakamadje forest massifs, respectively. The diameter and height distribution show an "L" shape reflecting juvenile vegetation. The analysis of Landsat images from 1990, 2005 and 2020 indicated an extension of agricultural lands (6234.54 ha in 1990 to 10,018.33 ha in 2020), bare soils/dwelling lands (14,049.90 ha in 1990 to 15,374.12 ha in 2020) and the degradation of shrub/tree savannah lands (74,312 ha in 1990 to 59,312.95 ha in 2020). The different forest massifs were rich, and anthropogenic activities were one of the main factors responsible for their degradation.