title: Use of slow-release fertilizer and biopolymers for stimulating hydrocarbon biodegradation in oil-contaminated beach sediments.
abstract: Nutrient concentration and hydrocarbon bioavailability are key factors affecting biodegradation rates of oil in contaminated beach sediments. The effect of a slow-release fertilizer, Osmocote, as well as two biopolymers, chitin and chitosan, on the bioremediation of oil-spiked beach sediments was investigated using an open irrigation system over a 56-day period under laboratory conditions. Osmocote was effective in sustaining a high level of nutrients in leached sediments, as well as elevated levels of microbial activity and rates of hydrocarbon biodegradation. Chitin was more biodegradable than chitosan and gradually released nitrogen into the sediment. The addition of chitin or chitosan to the Osmocote amended sediments enhanced biodegradation rates of the alkanes relative to the presence of Osmocote alone, where chitosan was more effective than chitin due to its greater oil sorption capacity. Furthermore, chitosan significantly enhanced the biodegradation rates of all target polycyclic aromatic hydrocarbons.
authors.affiliation: Department of Chemical and Biomolecular Engineering, 4 Engineering Drive 4, National University of Singapore, Singapore 117576, Singapore.
authors.forename: Ran
authors.initials: R
authors.lastname: Xu
authors.forename: Li Ching
authors.initials: LC
authors.lastname: Yong
authors.forename: Yong Giak
authors.initials: YG
authors.lastname: Lim
authors.forename: Jeffrey Philip
authors.initials: JP
authors.lastname: Obbard
mesh_terms: D000704:Analysis of Variance; D001419:Bacteria / Q000254:growth & development / Q000378:metabolism*; D001493:Bathing Beaches; D001673:Biodegradation, Environmental; D002245:Carbon Dioxide / Q000378:metabolism; D002686:Chitin / Q000378:metabolism; D048271:Chitosan / Q000378:metabolism; D004785:Environmental Pollutants / Q000032:analysis / Q000378:metabolism*; D005308:Fertilizers; D008401:Gas Chromatography-Mass Spectrometry; D019015:Geologic Sediments / Q000032:analysis*; D010088:Oxidoreductases / Q000378:metabolism; D010101:Oxygen Consumption / Q000502:physiology; D010578:Petroleum / Q000032:analysis / Q000378:metabolism*; D012846:Singapore
chemical_list: D004785:Environmental Pollutants; D005308:Fertilizers; D010578:Petroleum; D002686:Chitin; D002245:Carbon Dioxide; D048271:Chitosan; D010088:Oxidoreductases