Biomass and carbon stocks of woody vegetation across urban land-use units in the city of Kétou

Résumé

In urban environments, vegetation contributes to the maintenance of ecological functions but undergoes progressive degradation due to population growth and spatial expansion. In this context, a study was conducted to assess the carbon stock sequestered by woody vegetation across different land-use units in the city of Kétou. A systematic inventory was carried out to measure dendrometric parameters of trees within each unit, while allometric equations were used to estimate biomass and sequestered carbon. The results show that mean diameter varies among land-use units: 27.36 cm in built-up areas, 28.61 cm in cropland–fallow mosaics, 39.64 cm in tree and shrub savannas, and 41.63 cm in cropland–fallow mosaics under palm stands. Biomass is very low in built-up areas (11.07 t/ha), intermediate in cropland–fallow mosaics (123.94 t/ha), and high in tree and shrub savannas (210.89 t/ha) and palm-dominated mosaics (313.69 t/ha). This pattern is reflected in carbon stocks, which are low in built-up areas (5.53 tC/ha) and higher in cropland–fallow mosaics (61.97 tC/ha), tree and shrub savannas (105.44 tC/ha), and palm-dominated mosaics (156.84 tC/ha). The observed differences among land-use units are statistically significant (p = 0.0003), highlighting the influence of land-use type on carbon sequestration capacity. These results underscore the need for strategies aimed at the management and conservation of woody vegetation in Kétou.