Enhancing phytoremediation potential of <i>Andropogon tectorum</i> (Schumach & Thonn) in petroleum hydrocarbon contaminated soil using cassava peel

Abstract

This study investigated the effects of cassava peel amendment on phytodegradation of petroleum hydrocarbon polluted site grown with Andropogon tectorum. The study was carried out in Botem community in Tai Local Government Area of Rivers State. The experiment comprised four- treatment set-up; T₁ (Crude oil polluted soil + Andropogon tectorum), T₂ (Crude oil polluted soil + Andropogon tectorum + 500 g cassava peel), T₃ (Crude oil polluted soil + Andropogon tectorum + 1000 g cassava peel) and the control T₄ (Crude oil polluted soil alone). Soil/ plant hydrocarbon and soil physicochemical were done at 2 month interval after amendment and planting. Results showed higher reductions of total petroleum hydrocarbon (TPH) and total hydrocarbon content (THC) in treated soil (T₁, T₂ and T₃) than control. Highest percentage reduction in TPH (94.23 %) and THC (97.07 %) were obtained in soil phytoremediated with A. tectorum and 500 g cassava peel amendment while the control recorded the least (TPH: 14.76% and THC: 32.90 %). Alteration in the physico-chemical parameters with increase in soil pH and nitrogen was observed in phytoremediated soil with amendment. Results also showed accumulation of hydrocarbon in plants in all the treatments. Addition of cassava peel amendment (T₂ and T₃) increased TPH and THC accumulation in the test plant than the one without amendment T₁ (Andropogon tectorum only).This shows that cassava peel has the potential to enhance the rate of phytoremediation of hydrocarbon in Andropogon tectorum and should be considered in remediation of contaminated sites.

Keywords: phytoremediation, cassava peel, Andropogon tectorum, pollution, crude oil, soil.