Algalization of Acid Soils with Desmodesmus sp. MAS1 and Heterochlorella sp. MAS3 Enriches Bacteria of Ecological Importance

Abstract

Acid soils are the degraded (nutrient-poor) soils that generally lack microbial abundance required to promote plant growth. An insight into the microbial diversity in highly acidic soils is crucial from both ecological and environmental standpoints. Previously, we showed that inoculation of acid soils with acid-tolerant microalgae (algalization) significantly improved soil physicochemical and biological characteristics. In the present novel study involving a laboratory microcosm, high-throughput 16S rRNA amplicon sequencing analysis was performed to investigate the bacterial diversity in acid soils algalized with Desmodesmus sp. MAS1 and Heterochlorella sp. MAS3 after 90 days of incubation. Our results on pooled DNA demonstrate that algalization of two acid soils (soil A and B) significantly increased several bacterial genera, and this observation is consistent with Shannon and Chao1 diversity indices. Actinobacteria, Acidobacteria, Firmicutes, and Proteobacteria were the most prevalent phyla enriched in all of the algalized treatments. Interestingly, nonalgalized acid soils favored only Firmicutes and Actinobacteria, but algalization significantly enriched Proteobacteria, Acidobacteria, and Actinobacteria. Canonical correspondence analysis revealed a positive effect of pH in soil A and both pH and organic carbon in soil B on enrichment. Furthermore, soil bacteria of ecological significance that belong to rhizobacteria and diazotrophs, such as Acetobacter, Azospirillum, Bradyrhizobium, Gluconacetobacter, Nitrobacter, Burkholderia, Comamonas, Herbaspirillum, Enterobacter, Nitrosococcus, Brevibacillus, Enterococcus, Frankia, and Anabaena, were greatly enriched in algalized treatments. Thus, we demonstrate here for the first time that algalization of acid soils significantly improves soil health through enrichment of bacteria that are largely implicated in promoting soil health and plant growth.

The Potential of Microalgae–Bacteria Consortia to Restore Degraded Soils

“…Additionally, the authors reported an increase in the release of exopolysaccharides (more than 200%) which facilitate soil stability, an increase in carbon content (up to a 57%), an increase in dehydrogenase activity (more than 500%), and an increased production of indolacetic acid (between 200 and 500%) [68]. Furthermore, the algalization of acid soils with these species enhanced the richness of ecologically important soil bacteria, such as rhizobacteria and diazotrophs [69]. Muñoz-Rojas et al [70] also evaluated the potential of a cyanobacteria consortium with Nostoc commune, Tolypothrix distorta, and Scytonema hyalinum to restore mine soil and reported that up to 40% of the soil surface was covered by biocrust after 90 days, as well as a significant increase in soil organic carbon and the promotion of C sequestration.…”

Potential of microalgae and cyanobacteria to improve soil health and agricultural productivity: a critical view

“…195 The potential of the microalgae-and cyanobacteria-based products has been evaluated at various levels, more oen by researchers. Recently, Abinandan et al 196 demonstrated that algalization of two acid soils with Desmodesmus sp. MAS1 and Heterochlorella sp.…”

Teaching Acid–Base Fundamentals and Introducing pH Using Butterfly Pea Flower Tea

“…Young students are often more attentive to visually stimulating reactions in chemistry, , and the opportunity to mix chemicals with their own hands contributes to future chemistry identity on career intention . Acid–base chemistry is a natural phenomenon present in everyday life that is also important in research settings, such as wastewater treatment, , fertilizers, − catalysis, − drug development and delivery. − Additionally, pH indicators provide a direct visual portrayal of the concepts behind acids and bases. Thus, there is a unique opportunity to present acid–base chemistry in an exciting manner to help foster curiosity and drive young students to explore fundamental chemistry.…”