Effect of Mineral Carriers on Biofilm Formation and Nitrogen Removal Activity by an Indigenous Anammox Community from Cold Groundwater Ecosystem Alone and Bioaugmented with Biomass from a “Warm” Anammox Reactor

Abstract

The complex pollution of aquifers by reduced and oxidized nitrogen compounds is currently considered one of the urgent environmental problems that require non-standard solutions. This work was a laboratory-scale trial to show the feasibility of using various mineral carriers to create a permeable in situ barrier in cold (10 °C) aquifers with extremely high nitrogen pollution and inhabited by the Candidatus Scalindua-dominated indigenous anammox community. It has been established that for the removal of ammonium and nitrite in situ due to the predominant contribution of the anammox process, quartz, kaolin clays of the Kantatsky and Kamalinsky deposits, bentonite clay of the Berezovsky deposit, and zeolite of the Kholinsky deposit can be used as components of the permeable barrier. Biofouling of natural loams from a contaminated aquifer can also occur under favorable conditions. It has been suggested that the anammox activity is determined by a number of factors, including the presence of the essential trace elements in the carrier and the surface morphology. However, one of the most important factors is competition with other microbial groups that can develop on the surface of the carrier at a faster rate. For this reason, carriers with a high specific surface area and containing the necessary microelements were overgrown with the most rapidly growing microorganisms. Bioaugmentation with a “warm” anammox community from a laboratory reactor dominated by Ca. Kuenenia improved nitrogen removal rates and biofilm formation on most of the mineral carriers, including bentonite clay of the Dinozavrovoye deposit, as well as loamy rock and zeolite-containing tripoli, in addition to carriers that perform best with the indigenous anammox community. The feasibility of coupled partial denitrification–anammox and the adaptation of a “warm” anammox community to low temperatures and hazardous components contained in polluted groundwater prior to bioaugmentation should be the scope of future research to enhance the anammox process in cold, nitrate-rich aquifers.

The cultivation regimes of Morchella sextelata trigger shifts in the community assemblage and ecological traits of soil bacteria

“…Among the taxa that were positively correlated with morel abundance, several families have been identified as N-fixing bacteria, including Rhizobiaceae, Devosiaceae, Rhodobacteraceae, and Xanthomonadaceae ( Rivas et al, 2002 ; Altshuler et al, 2019 ; Rosselli et al, 2021 ). In addition, families such as Cellvibrionacea, Comamonadaceae, Sphingomonadaceae, Methylophilaceae, Sphingobacteriaceae, and Flavobacteriaceae have been identified as denitrifying bacteria ( Khan et al, 2002 ; Li et al, 2019 ; Zhou et al, 2019 , 2021 ; Vishnyakova et al, 2022 ). In contrast, taxa that showed a negative correlation with morel abundance, including Actinobacteria, Firmicutes, Gemmatimonadota, and Nitrospirota, at the phylum level, were identified as potential nitrifying bacteria ( Zhou et al, 2020 ; Lu et al, 2022 ).…”

“…Denitrifying bacteria are responsible for the conversion of nitrate to N 2 ( Vishnyakova et al, 2022 ). This denitrification process is closely linked to SOM, because heterotrophic bacteria utilize organic carbon sources for their metabolism during denitrification ( Burford and Bremner, 1975 ).…”

Microbial and Monosaccharide Composition of Biofilms Developing on Sandy Loams from an Aquifer Contaminated with Liquid Radioactive Waste

“…The fluorescent dye SYTO 11 (S7573, Thermo Fisher, USA; 1:1000 dilution) binds to nucleic acids. Staining was conducted as described in [ 48 ]. To assess the protein component of the biofilms, a fluorescent derivative of fluorescein (FITC) was used (Merck, Darmstadt, Germany).…”

In Situ Biogeochemical Barriers for Contaminated Groundwater Treatment near Uranium Sludge Storages

“…The formation of biofilms on rocks provides the formation of microbial communities resistant to toxic loads. Biofouling of pure quartz is generally not very high [2];…”