Growth Response of Grass Species in Oil-Based Drill Cuttings Contaminated Soils

Abstract

Growth response of selected tropical grass species in oil-based drill cuttings contaminated soils was examined in this study. The contamination experiment was simulated in a randomized complete block design by factorial of 6 x 3 x 2 x 2 for grass species (Pennisitum purpureum, Panicum maximum, Andropogon gayanus, Heteropogon contortus, Axonopus compressus, and Chloris virgata), treatments (0%, 25%, and 50% oilbased drill cuttings contamination), time (day 1 of planting and 105 days of harvesting), and growth stage (young and mature). The parameters assessed were plant height, leaf length, width and area, fresh and dry shoot and root biomass, root length, and root to shoot ratio. Fastest growth in plant height was noticed in P. maximum. Good growth in height was also achieved in A. compressus and P. purpureum. Mature H. contortus had the fastest growth in leaf width, followed by young P. maximum and A. gayanus. Young and mature P. purpureum had highest shoot and root biomass. Biomass of P. maximum in response to oil-based drill cuttings was tilted to root biomass. Shoot biomass was favoured in A. compressus, A. gayanus, C. virgata, and mature P. purpureum. H. contortus and young P. purpureum had a balance of root and shoot biomass growth. P. purpureum showed longest root length and mature C. virgata showed shortest route length. Thus, the best performing grass species were P. maximum, A. compressus, P. purpureum, H. contortus, and A. gayanus.