Effect of biochar amendment on soil microbial biomass, abundance and enzyme activity in the mash bean field
By: Muhammad Azeem, Rifat Hayat, Qaiser Hussain, Mukhtar Ahmed, Muhammad Imran, David E. Crowley
Key Words: Biochar, Microbial biomass, Enzyme, Legume.
J. Bio. Env. Sci. 8(6), 1-13, June 2016.
Biochar is being evaluated globally as a means to improve soil fertility, ecosystem services and sequester carbon. The present study was conducted in the arid zone agricultural region of Pakistan to investigate the impact of biochar on the soil microbial biomass, abundance, and activity in the rhizosphere of mash bean crop. For this, pyrolyzed biochar of sugarcane bagasse was prepared and applied at rates of 0, 0.25 and 0.5%-C (C-equivalent basis) with and without NPK fertilization (23 N, 45 P and 25 K kg ha-1). Biochar treatments were applied before sowing of mash bean, and the soil samples were taken from each treatment plot at crop maturity. Bacterial 16S rRNA gene copy numbers were significantly increased with biochar (132%) and NPK fertilization (27%) in mash bean, while 18S rRNA was significantly decreased with biochar application by 22%. 18S abundance was increased (20%) when biochar was applied along with chemical fertilizer. Microbial biomass carbon and nitrogen increased by 19% and 67% with biochar amended at 0.5%-C. Urease and dehydrogenase activities significantly increased with biochar applied at 0.5%-C and NPK fertilization. The results suggest that the application of sugarcane bagasse-derived biochar can be useful in improving the legume yield and soil functions in the calcareous soil of the arid area.