Details

Autor(en) / Beteiligte

• Lin, Zhong
• Zhen, Zhen
• Liang, Yanqiu
• Li, Jin
• Yang, Jiewen
• Zhong, Laiyuan
• Zhao, Lirong
• Li, Yongtao
• Luo, Chunling
• Ren, Lei
• Zhang, Dayi

Titel

Changes in atrazine speciation and the degradation pathway in red soil during the vermiremediation process

Ist Teil von

• Journal of hazardous materials, 2019-02, Vol.364, p.710-719

Ort / Verlag

Netherlands: Elsevier B.V

Erscheinungsjahr

2019

Quelle

MEDLINE

Beschreibungen/Notizen

• •Vermiremediation improves atrazine removal efficiency from 39.5% to 94.1–95.7%.•Vermiremediation neutralizes soil pH and consumes organic matter.•Increased atrazine availability in vermiremediation treatments.•Altered atrazine degradation pathway from hydrolysis to deethylation/deisopropyl. Atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) is a triazine herbicide intensively used in agricultural production and is often detected in different environmental matrices at concentrations above the permitted limit. This study investigated the influence of two earthworm species (epigeic Eisenia foetida and endogeic Amynthas robustus) on atrazine speciation and the degradation pathway. Our results revealed that both earthworms significantly accelerated atrazine degradation in a 28-day vermiremediation, and the residual atrazine declined from 4.23 ± 0.21 mg/kg in bulk soils to 0.51 ± 0.29 mg/kg (E. foetida) and 0.43 ± 0.19 mg/kg (A. robustus). By consuming organic matter (from 40.37 ± 1.14 to 36.31 ± 1.55 and 34.59 ± 1.13 g/kg for E. foetida and A. robustus) and neutralizing the soil pH (from 5.37 ± 0.27 to 6.36 ± 0.11 and 6.61 ± 0.30 for E. foetida and A. robustus), both earthworms reduced humus-fixed atrazine and increased the available atrazine. The percentage of available atrazine increased from 8.80 ± 0.21% in bulk soil to 10.30 ± 0.29% and 16.42 ± 0.18% in the vermiremediation treatments. Both earthworms promoted the hydroxyatrazine pathway by consuming soil organic matter and encouraged the deethylatrazine/deisopropylatrazine pathway by neutralizing the soil pH. Our findings unravel a new mechanism of vermiremediation by improving the soil physical-chemical properties and altering the atrazine degradation pathway, providing new insights into the influential factors on atrazine bioremediation in red soil.