The average soil carbon content (depth 0–100 cm) was estimated as 160 Mg·ha−1
. The total carbon
in soil recorded in this study is lower when compared with the soil carbon reported in other mangrove
forests in the same depth (0–100cm). As an example, Kauffman et al. [51], found 236 Mg·ha−1 of soil carbon at Yap mangrove forest; Adame et al. [38] found 232.4 Mg·ha−1 of soil carbon at Isla Pitaya,
while Bosire et al. [30], found an average of 321 Mg·ha−1 soil carbon in mangrove forests of
Zambezi Delta, Mozambique, about 150 Km North of our study area. Neighboring upland forest soil
carbon, however, is reportedly lower than the figures found in this study. For instance, Walker and
Desanker [49] found an average of 85 Mg·ha−1
up to a depth of 150 cm in miombo woodlands of
Malawi. In miombo woodlands of Gondola, just 100 km West of the study site, Tomo [27] found a
median soil carbon of 58 Mg·ha−1
up to a depth of 30 cm, with a high variability (range
18–140 Mg·ha−1
), comparable to the average of 53.3 Mg·ha−1
found in the topsoil (0–30 cm) in this
study, but in general, lower when considering the sharp decrease with depth in miombo woodlands.
The low carbon value found in our study could be explained by the low carbon content in the soil,
supporting what has been reported by Kairo et al. [43], which is that the difference in soil carbon
stocks in different regions could be explained by the difference of carbon content across depth layers
in each region. The high level of mangrove disturbance and degradation in our study area could be one
of the reasons of the current state of carbon stock