Agriculture Practice and Its Impact on Forest Cover and Individual Trees in the Mount Cameroon Region

Abstract

Land use changes are driven by agricultural intensification. The aim of the study was to evaluate the impact of agriculture practice on forest cover and tree damage. For this, the Mount Cameroon Region was selected as the research site. Semi-structured questionnaires, interviews and focused group discussions were carried out to collect socio-economic data. In addition, field surveys and remote sensing techniques were used. Thus, ten 50 × 50 m sample plots were established in newly opened farms in the study sites. All trees damaged by fire during farming were sampled and the diameter at breast height (dbh ≥ 10 cm) recorded. Ground truthing was done to obtain ground reference data. During this survey, geographical positioning system (GPS) points were recorded from different land uses observed (farmlands, forests, bare ground, plantations and settlement areas) using Garmin eTrex Venture HC GPS. Landsat Thematic (TM) and Enhanced Thematic (ETM+) images were extracted for the years 1986, 2000 and 2008. The results showed that the number of farms cultivated per household correlated positively with the family sizes of the respondents (r= 0.98). The annual deforestation rate was 1.09% from 1986-2000, and 0.58% from 2001-2008. Noticeably, agricultural fields were increased by 12 ha annually from 1986-2000, while they were decreased by 33.5 ha from 2001-2008. A total of 460 trees belonging to 98 species of 33 families were damaged. The average basal area of the trees was 1.3 m2. The highest damage was noticed in Malvaceae. The most important species damaged were Terminalia superba, Xylopia africana and Entandrophragma cylindricum. Massive tree destruction was recorded due to land use changes specifically agricultural expansions, illegal logging and fuel wood collection with consequent threats to forest biodiversity.