Quantification of the effects of management factors on maize(Zea mays L. ) and cotton (Gossypium hirsutum L. ) residues decomposition rate

Article type: Research Article

Authors: Jones, Chilima | Huang, Chang-yong | Wu, Ci-fang

Affiliations: College of Natural Resources and Environment, Zhejiang University, Hangzhou 310029, China; E-mail: [email protected]

Abstract: Efforts to quantify management effects on decomposition rate of added substrates to the soil is important especially where such information is to be used for prediction in mathematical or simulation models. Using data from a short-term (60 days) greenhouse simulation study, a procedure for quantifying effects of management on SOM and substrate decomposition is presented. Using microbial growth rate u ( q ),microbial efficiency in substrate utilization e (q), specific decomposition rates for added plant residues to two contrasting soils, red earth (Ferrasol) and black earth (Acrisol) were estimated. The treatments included straw addition + buried, (T1); straw addition + mineral N (T2); and straw addition + tillage, (T3). Sampling was done every 15 days. Straw decomposition rate was affected by external mineral N sources (Urea 46% N). Addition of an external N source significantly increased decomposition rates. The study could not, however, fully account for the effect of tillage on residues because of the limited effect of the tillage method due to the artificial barrier to mechanical interference supplied by the mesh bags. It is concluded that using few decomposer parameters, decomposition rates and consequently SOM trends in a soil system can be monitored and quantification of the influence of perturbations on decomposition rate of added substrates possible.

Keywords: management factors, residue decomposition rate, maize, cotton, red soil, black soil

Journal: Journal of Environmental Sciences, vol. 14, no. 2, pp. 165-172, 2002