Carbon of Chaillu forests based on a phytosociological analysis in Republic of Congo, more than meets the eye?

Abstract

AbstractThe objectives were to quantify aboveground, belowground and dead wood carbon pools near Mayoko in the Chaillu massif of Republic of Congo and explore relationships between carbon storage and plant diversity of all growth forms. A total of 190 plots (25 m by 25 m) were sampled (5072 stems, 211 species) and data analysed using recommended central‐African forest allometric equations. Mean stem diameter at breast height was 33.6 cm, mean basal area 47.7 m2 ha−1 and mean density of individuals 407 ha−1. Mean aboveground carbon (AGC) ranged from 13.93–412.66 Mg C ha−1, belowground carbon from 2.86–96.97 Mg C ha−1 and dead wood from 0.00–7.59 Mg C ha−1. The maximum AGC value recorded in a plot was 916 Mg C ha−1. The analysis performed using phytosociological association as basis rather than broad vegetation type is unique. AGC values for undisturbed terra firme forest sites featured among the highest recorded for African tropical forests. Considering only tree diversity, a weak, yet significant, relationship existed between AGC and species richness, Shannon‐Wiener index of diversity and Fisher's alpha. However, if diversity of all plant growth forms is considered, no relationship between carbon and plant diversity existed.