Abstract:
Few studies have determined the soil organic carbon (SOC) stocks in the
Miombo woodlands ecosystem in Tanzania. Standard field and laboratory
procedures were used to evaluate SOC storage in the Miombo woodlands
ecosystem of Kitonga Forest Reserve Iringa, Tanzania. A study area of 52 km 2
was selected and ten soil profiles were studied. Representative sampling
points were geo-referenced and soil samples collected from natural horizons
to the depth of 60 cm. Results show that the total soil organic carbon stocks in
soil profiles varied from 19.4 to 28.9 Mg C ha -1 in leptosols; from 45.6 to 80.1
Mg C ha -1 in fluvisols; and from 33.9 to 134.6 Mg C ha -1 in cambisols. The SOC
increased significantly (p< 0.05) with increasing elevation, horizon thickness
and % clay, but it decreased significantly (p< 0.05) with increasing slope
gradient and increasing % sand. The areal distribution of the soil types was
61%, for cambisols, 19% for leptosols, 11% for fluvisols and 9% for natural
forest which was not surveyed because of inaccessibility. Proper management
of Miombo woodlands would increase the SOC storage and contribute to
climate change regulation.
