EFFECTS OF ANTHROPOGENIC DISTURBANCES ON BIOMASS AND POTENTIAL CARBON STORAGE IN LAF FOREST RESERVE (CAMEROON)

Forested zones represent habitats where the greatest quantity of biomass and carbon are concentrated. The survey assessed the spatio-temporal dynamics of the landscapes of Laf forest reserve and the effect of human activities on its biomass and carbon storage. We used diachronic analysis of two Landsat satellite images LCOS_LITP of 1999 and 2019, which were processed using ArcGIS software. Three collection units (CU) were considered: i) CU1 at the periphery ii) CU2 installed at 200 m from CU1, and iii) CU3 at the middle of the reserve in order to estimate biomass and carbon storage in relation to anthropogenic disturbances. In each CU, transects of 1000 m x 20 m were installed, and within each transect, all trees with a diameter at breast height (dbh) ≥ 10 cm were recorded and characterized by the following attributes: species name, dbh at 1.30 m above ground level and height. Individuals which branch before 1.30 m were measured at 10 cm from the soil. The results indicate that the extension of the agricultural land passed from 630.42 ha in 1999 to 3094.17 ha in 2019. A total of 6866 trees was recorded, representing 55 species, 37 Genera and 21 Families. Basal areas were: CU1 (BA = 6.11 m2/ha) CU2 (BA = 18.00 m2/ha) and CU3 (BA = 16.81 m2/ha). All the collection units were characterized by low Shannon diversity index (ISH < 3.5 bits). The woody biomass and carbon storage were: CU1 (TB= 6.33 t/ha CS= 2.98 tC/ha) CU2 (TB= 16.12 t/ha CS= 7.6 tC/ha) CU3 (TB= 12.46 t/ha CS= 5.86 tC/ha). The equivalent carbons were as follows: CU1 (CO2 eq= 10.93 t/ha) CU2 (CO2 eq= 27.89 t/ha) and CU3 (CO2 eq= 21.5 t/ha). There was a significant difference between CU1 and the two other collection units (p < 0.001). The Laf Forest Reserve appears to be heavily disturbed particularly near villages. CU2 performs the most important quantity of carbon storage due to enrichment plantations. Management efforts are required for the recovery of the reserves ecosystems.