Bin Yao;Xiaobo Gu;Shu YingGe;Fang Bao;Yonghua L

Ecology and Environment Department of Guizhou University, Guiyang, People’s Republic of China;Beijing Municipal Research Institute of Environmental Protection, Beijing, People’s Republic of China;Institute of Desertification Studies, Chinese Academy of Forestry, Beijing, People’s Republic of China;Institute of Desertification Studies, Chinese Academy of Forestry, Beijing, People’s Republic of Chin

Atrazine;Dendroremediation;Poplar;Biodegradation;Microbes;MICROBIAL BIOMASS CARBON;PHYTOREMEDIATION;BIOACCUMULATION;HERBICIDES;TOLERANCE;STRAIN;PLANTS;TREE

Dendroremediation, a novel strategy for cleaning up contaminants from the environment by using special woody plant species and microbes, is a popular phytoremediation approach. It is a cost-effective and environmentally friendly method that is being increasingly adopted. Poplar species (Populus L.) have been suggested for use in remediation because of their characteristics of high biomass production, fast growth, and potential for removing pollutants. Our environment is often contaminated by toxic substances produced by human activities, and remediation of contamination is therefore a global issue. Atrazine is one of the most widely used herbicides in China. In the present study, 'I-69/55' poplar (P. deltoides cv. 'I-69/55') and hybrid poplar (Populus deltoidesxnigra, DN34) grown in pots were assayed for their ability to remediate atrazine-contaminated soils. The degradation dynamics of atrazine were assessed with a high-performance liquid chromatography system using materials from a greenhouse with different rhizosphere environments. We studied the dynamic variation in microbes and microbial biomass carbon to elucidate the rhizosphere effects and mechanism of remediation of atrazine-contaminated soil by poplar. Our four treatments included a control with uncontaminated soil without a tree, atrazine pollution without a tree, atrazine pollution with 'I-69/55' poplar, and atrazine pollution with hybrid poplar. Hybrid poplar showed potential for remediation of atrazine-contaminated soil, and the degradation of atrazine in the rhizosphere was faster than that in non-rhizosphere soil. Atrazine significantly inhibited bacteria growth in non-rhizosphere soil. The high concentration of bacteria in the hybrid poplar rhizosphere might be key to atrazine degradation. Trends of change among fungi and actinomyces did not correspond to trends in atrazine degradation throughout the trial period. Further research is needed to predict the effects of atrazine on cultivable microorganisms in various soils. Atrazine had significant inhibitory effects on microbial biomass carbon in non-rhizosphere soil, and the rhizosphere environment of poplars enhanced the recovery of microbial biomass carbon. The potential for hybrid poplar as a dendroremediation material needs further study.