TITLE:
Microbial Properties of a Ferric Lixisol as Affected by Long Term Crop Management and Fertilization Regimes in Burkina Faso, West Africa
AUTHORS:
Noufou Ouandaogo, Mathias Bouinzemwendé Pouya, Dohan Mariam Soma, Zacharia Gnankambary, Delwendé Innocent Kiba, Badiori Ouattara, François Lompo, Hassan Bismark Nacro, Papaoba Michel Sedogo
KEYWORDS:
Microbial Respiration, Bacteria Quantification, Compost, Crop Rotation, Sorghum, Cowpea
JOURNAL NAME:
Open Journal of Soil Science,
Vol.11 No.4,
April
26,
2021
ABSTRACT: We used an
ongoing long-term field trial established since 1960 in Burkina Faso, to study
the microbial properties of a Ferric Lixisol under various crop management and
fertilization regimes. Microbial respiration rate, microbial biomass carbon
(MBC) and soil bacteria’s number were assessed in soil samples taken at 0 - 20 cm
depth. The crop management were continuous cropping of sorghum (Sorghum
bicolor L.) (S/S) and rotation between sorghum and cowpea (Vigna
unguiculata L.) (S/C), while the fertilization regimes were: 1)
Control (te); 2) Low rate of mineral fertilizer (fm); 3) Low rate of mineral
fertilizer + sorghum straw restitution (fmr); 4) Low rate of mineral fertilizer
+ low rate of manure (fmo); 5) High rate of mineral fertilizer (FM); and vii)
High rate of mineral fertilizer + high rate of manure (FMO). The manure is
applied every second year. The results indicate that sorghum/cowpea rotation
significantly increase MBC and bacteria number as compared to continuous
sorghum cropping. MBC ranged from 335.5 to 54.85 μg C g−1 soil
with S/S and from 457.5 to 86.6 μg C g−1 soil
with S/C. Application of high level of manure and mineral fertilizer increase
microbial respiration rate and MBC. The highest MBC was observed with FMO and
the lowest with the control. In general, the metabolic quotient (qCO2)
was negatively impacted by the fertilization and cowpea rotation. For S/S
rotation, qCO2 of the control was 1.5 to 2 times that of the
treatments with low mineral fertilizer (fmr, fmo and fm) and 3 times that of
the high rate of fertilization (FM and FMO). With S/C rotation, qCO2 of the control was 2 times of that fmr, FM and FMO and 0.8 times that of fmo
and fm. Soil bacteria in the fmr were 63.6 and 12.4 times the control in the
S/S and S/C rotations, respectively. In sum, combined application of manure and
mineral fertilizer with crop rotation is the best management practices to
improve in sustainable way microbial activities in tropical soil.