Exploitation of Native Plants and Microbial Diversity Profiling for Phytoremediation of Petroleum Hydrocarbon Contaminated Coastal Wetland Soil

Soil pollution by Petroleum Hydrocarbon (PHC) in the coastal wetland of Yellow River Delta, China has seriously threatened ecosystem health and function. Phytoremediation is an innovative and cost-effective option to remediate the contaminated soil. However selection of the suitable plant species is an important step for successful bioremediation of the PHC contaminated soils. The biodegradation abilities of five plant species including Susana, Seep weed, Sea-lavender, and Central Asia Saltbush grown in the PHC contaminated soil was investigated using a 90-day pot experiment. The removal of PHC in the rhizosphere soils was more efficient compared to the without planted soils (64.8% vs 20.2%) With reference to plant properties, the biomass surface area and volume of the roots were negatively correlated with PHC concentration (r=-0.816,-0.869 and -0.90, P<0.05, n=10) respectively, confirming that plant with higher biomass and larger root resulted in more PHC remediation. The Bio Log community profile illustrated that Sesbania rhizo sphere was the most dynamic micro zone. In addition the rhizosphere soil pH declined from 7.94 to 7.58 during the incubation period. Overall Sesbania with higher biomass and larger root system and active microbial diversity (Shannon diversity index 3.2 on 90 day) was an ideal plant for on-site remediation of the petroleum polluted coastal wetland soils.