Effects of two ecological earthworm species on atrazine degradation performance and bacterial community structure in red soil

Abstract

Vermicomposting is an effective and environmentally friendly approach for eliminating soil organic contamination. Atrazine is one of the most commonly applied triazinic herbicides and frequently detected in agricultural soils. This study investigated the roles and mechanisms of two earthworm species (epigeic Eisenia foetida and endogeic Amynthas robustus) in microbial degradation of atrazine. Both earthworms accelerated atrazine degradation performance from 39.0% in sterile soils to 94.9%-95.7%, via neutralizing soil pH, consuming soil humus, altering bacterial community structure, enriching indigenous atrazine degraders and excreting the intestinal atrazine-degrading bacteria. Rhodoplanes and Kaistobacter were identified as soil indigenous degraders for atrazine mineralization and stimulated by both earthworm species. A. robustus excreted the intestinal Cupriavidus and Pseudomonas, whereas Flavobacterium was released by E. foetida. This study provides a comprehensive understanding of the distinct effects of two earthworm species on soil microbial community and atrazine degradation, offering technical supports to apply vermicomposting in effective soil bioremediation.

Peer Review #1 of "TiO2 nanoparticles affect the bacterial community structure and Eisenia fetida (Savigny, 1826) in an arable soil (v0.3)"

“…Earthworm activity will accelerate the degradation of organic material and this will change soil characteristics, such as soil structure and pH (Bernard et al, 2012). These changes controlled by the initial soil conditions, food and earthworm activity might alter the bacterial community structure (Lin et al, 2018). In this study, the bacterial community structure was different between Manuscript to be reviewed Proteobacteria, TM6 and Verrucomicrobia, while reducing most other bacterial phyla.…”

STUDY OF THE DEGRADATION OF CHLORPYRIFOS IN CONTAMINATED SOILS IN THE PRESENCE OF THE RED CALIFORNIA EARTHWORM Eisenia foetida

“…Then, the recognizable symptoms of poisoning disappeared approximately 14 to 21 days after exposure (Aamodt et al 2007). Sampling was determined after 0, 7, 14, 21 and 28 days according to the Lin's method (Lin et al 2018).…”

“…For this reason, bioremediation stands as an alternative to break down pesticides into simpler compounds, thus rendering them less dangerous, through the use of the metabolic potential of microorganisms (Hernández et al 2017). Studies show that the use of worms considerably increases the degradation of pesticides such as metolachlor (Sun et al 2019), acetochlor (Hao et al 2018), and atrazine (Lin et al 2018) by microbial communities in the soils.…”

Variation of Microbial Communities in Aquatic Sediments under Long-Term Exposure to Decabromodiphenyl Ether and UVA Irradiation

“…Flavisolibacter has been reported to be an important and sensitive indicator of the presence of a range of POPs in soils, such as carbamazepine and triclosan [9,49]. Furthermore, it has been shown that atrazine is biodegraded by Flavisolibacter during the vermicomposting process [50].…”