Abstract:
The aim of this study was to
determine the species diversity and carbon
storage potential of herbaceous plants
growing within selected dumpsites in the
Abakaliki metropolis. The line transect
method was used to collect plants from five
study stations: Waterworks (A), Kpirikpiri
(B), Newlayout (C), FETHA (D) and Presco
(E). At each study station, a 15 m×30 m area
was measured using tape and demarcated
with pegs and ropes. The identified species
were collected, the biomass, species
frequency, density, dominance, diversity and
carbon uptake were measured. The diversity
indices evaluated showed that active dump
station A was the most diverse and evenly
distributed site (Shannon–Weiner diversity
index: A=2.43, B=1.09, C=1.16, D=1.14,
E=0.99, Pileou’s evenness index, A=1.53,
B=0.70, C=0.68, D=0.66, E=0.69).
Additionally, at station D, Simpson’s
dominance (A=0.27, B=0.32, C=0.24,
D=0.43, E=0.10) and Magalef (species
richness) indices (A=1.7, B=4.07, C=3.75,
D=4.20, E=3.38) were the highest. The
herbaceous Ghomphrena celeisoides had the
highest relative dominance, relative
frequency and important value index across
the studied stations. Analysis of variance of
the carbon uptake potentials of species
showed significant values for abandoned
dump stations C (Newlayout) and D
(FETHA) when p<0.05. Therefore, total
sequestered carbon in stations C (F=15.97,
p<0.001) and D (F=8.33, p<0.001) and
sequestered carbon dioxide equivalent at
stations C (F=15.96, p<0.001) and D
(F=43.68, p<0.001) were significant at 95％
confidence level. The results indicate that
species at dormant waste disposal sites
sequester significant amounts of carbon;
therefore, they are recommended for the
phytoremediation of disturbed or destroyed
ecosystems.
