Influence of Artificial Root Exudates on Triclosan Removal in Soil under Aerobic and Anaerobic Conditions

Abstract

A batch experiment is conducted to evaluate the influence of root exudates on the removal of triclosan (TCS) in soil samples under aerobic and anaerobic conditions. The BIOLOG method and quantitative real‐time PCR (qPCR) is used to analyze the microbial metabolic characteristics and bacterial absolute abundance, respectively. The results shows that TCS is removed relatively faster in aerobic groups than anaerobic ones, especially in the aerobic group with artificial root exudates solution (ARES) addition. However, no difference can be seen in TCS removal performance between anaerobic groups with or without ARES addition (p > 0.05). The results of BIOLOG show that the average metabolic activity of microorganisms (AWCD) increases significantly in the aerobic group with ARES addition with time, followed by the aerobic control group and anaerobic groups. The carbon source utilization behavior of soil microbes exhibit significant differences. Carbohydrates can be utilized easily in the aerobic group with ARES addition, while the fractional content of amines in the anaerobic group with ARES is highest. Furthermore, bacterial abundance shows positive correlation with the TCS removal under aerobic conditions. Overall, ARES addition can greatly promote the removal efficiency of TCS under aerobic conditions, but have a small effect under anaerobic conditions.