Abstract:
Grasslands are believed to store carbon in below and above ground. However, little is
known on the actual proportion amount of carbon stored in the different carbon pools in
the grassland ecosystems. This study aimed at quantifying below and above ground
carbon stocks of floodplain and upland grasslands. Quadrants measuring 1 m2 were
established systematically along transects in the floodplain and upland grasslands. Above
ground vegetation and litter were sampled in 1 m x 1 m plots and below ground roots and
soils were sampled in pits of 0.5 m x 0.5 m x 0.6 m. Soil samples were taken from 0 – 15
cm, 15 – 30 cm, 30 – 45 cm and 45 – 60 cm depth. Carbon in shoots, litter and roots was
determined by Loss on Ignition method. Carbon in soils was determined by Walkley Black
method. Data were analyzed using descriptive statistics and ANOVA. The above ground
carbon in upland grassland was 12.60 } 0.50 t ha-1 and 3.09 } 0.11 t ha-1 for vegetation and
litter respectively. Below ground carbon was 7.82 } 0.57 t ha-1 for roots and 40.26 } 1.17 t
ha-1 for soils. In the floodplain grasslands above ground carbon was 33.04 } 1.18 t ha-1 for
vegetation and 1.89 } 0.08 t ha-1 for litter. On the other hand below ground carbon was
6.22 } 0.25 t ha-1 and 24.63 } 0.88 t ha-1 for roots and soil respectively. In total upland
grasslands has potential to store 63.77 } 2.35 t ha-1 of carbon while the floodplain
grasslands storage was 65.78 } 2.39 t C ha-1. With exception of roots all other pools
showed a significant difference in carbon storage between floodplain and upland
grasslands (P = 0.000). Both upland and floodplain grasslands have high potential for
carbon storage and emission mitigation.
