Design, Performance Evaluation and Investigation of the Dynamic Mechanisms of Earthworm-Microorganisms interactions for wastewater treatment through Vermifiltration technology

Abstract

The present study points to the relevance of the earthworm microorganisms symbiotic and synergistic interactions that drive the wastewater treatment by identifying the most essential mechanisms underlying the removal of contaminants during vermifiltration technology. Previous studies have showed the presence of earthworms improves treatment performance of vermifilter (VF), but earthworm microbial community dynamics, their structure and functional characteristics in VF were not fully investigated. To investigate the effects of earthworms on the inherent microbial community of the VF, the present study envisages the dynamics of the complex symbiosis of earthworms & microorganisms associated to the treatment mechanisms. In this study, the design, operations and performance evaluation and influent, effluent and filter media layer were investigated for microbial diversity inside the earthworm population, along with the antimicrobial activity, enzymatic activity, and protein profiling assays. The results showed that earthworm gut microbial communities were dominated by Gammaproteobacteria, and the percentages arrived to 59 to 60% of the microbial species detected, while filter media layer showed presence of Firmicutes and Actinobacteria. The protein profiling of the microbiota associated with the VF showed that earthworms feeding and earthworm microorganism interaction were responsible for enhanced treatment performance. The finding provides an insight into the complex earthworm microbial dynamics and mechanisms for wastewater treatment in VF. Furthermore, earthworm predation strongly regulated microbial biomass while improving microbial activity, and is deciphered as the possible mechanisms behind the vermifiltration technology.

Microplastics in agroecosystems: A review of effects on soil biota and key soil functions

“…(2021), with addition of PE particles (concentrations: 21.36%: <100 µm; 68.43%: 100–200 µm; 10.21%: >200 µm), soil C:N ratio decreased in presence of earthworms. Earthworms can potentially lower the C:N ratio by adding mucus, body fluids, enzymes, excreta as sources of N to the soil substrate (Arora et al., 2020; Zhong et al., 2021).…”

A robust multicriteria analysis for the post-treatment of digestate from low-tech digesters. Boosting the circular bioeconomy of small-scale farms in Colombia

“…Moreover, combining a degassing tank with a sand filter, a vermifilter or a facultative pond is also considered due to their complementary nature. Most of these technologies have been studied mainly for the treatment of urban wastewater [43], [44], [45], and only a few studies were carried out with digestates. For instance, Patil & Husain [46] used a sand filter to post-treat digestate coming from the anaerobic digestion of kitchen waste, and provided a database including the removal of organic matter and lifespan of the system.…”