Comparative Characterization of Bacterial Communities in Moss-Covered and Unvegetated Volcanic Deposits of Mount Merapi, Indonesia

Abstract

Microbial colonization, followed by succession, on newly exposed volcanic substrates represents the beginning of the development of an early ecosystem. During early succession, colonization by mosses or plants significantly alters the pioneer microbial community composition through the photosynthetic carbon input. To provide further insights into this process, we investigated the three-year-old volcanic deposits of Mount Merapi, Indonesia. Samples were collected from unvegetated (BRD) and moss-covered (BRUD) sites. Forest site soil (FRS) near the volcanic deposit-covered area was also collected for reference. An analysis of BRD and BRUD revealed high culturable cell densities (1.7–8.5×105 CFU g−1) despite their low total C (<0.01%). FRS possessed high CFU (3×106 g−1); however, its relative value per unit of total C (2.6%) was lower than that of the deposit samples. Based on the tag pyrosequencing of 16S rRNA genes, the BRD bacterial community was characterized by a higher number of betaproteobacterial families (or genus), represented by chemolithotrophic Methylophilaceae, Leptothrix, and Sulfuricellaceae. In contrast, BRUD was predominated by different betaproteobacterial families, such as Oxalobacteraceae, Comamonadaceae, and Rhodocyclaceae. Some bacterial (Oxalobacteraceae) sequences were phylogenetically related to those of known moss-associated bacteria. Within the FRS community, Proteobacteria was the most abundant phylum, followed by Acidobacteria, whereas Burkholderiaceae was the most dominant bacterial family within FRS. These results suggest that an inter-family succession of Betaproteobacteria occurred in response to colonization by mosses, followed by plants.

Plant growth promoting potential of Arthrobacter spp., an early colonizer on the volcanic deposits of Mt. Merapi, Indonesia, as a restorative agent for degraded land

“…(lady fern), Imperata cylindrica (cogon grass), and Anaphalis javanica (Javanese edelweiss). The TC and TN contents on the site were reported almost undetected [23].…”

“…Merapi, Special Region of Yogyakarta Province (07°34̍ 39̎ S, 110°26̍ 51̎ E, and 1,199 m.a.s.l.) [23]. The deposit sampled site (site BRU) was dominantly inhabited by pioneer moss namely Campylopus umbellatus and partly by Athyrium sp.…”

“…Merapi, Indonesia and Miyake-jima, Japan have shown that Arthrobacter spp. were the predominant bacteria in the pioneer communities [23,24]. Therefore, the aim of this study is to explore the biochemical and physiological traits of Arthrobacter strains isolated from the volcanic environments and evaluate their potential as PGPB.…”

A Nitrate-Transforming Bacterial Community Dominates in the Miscanthus Rhizosphere on Nitrogen-Deficient Volcanic Deposits of Miyake-jima

“…Fujimura et al, (2012 and 2016) revealed the role of early microbial communities in supporting pioneering plant colonization in unvegetated volcanic deposits, suggesting that the bacterial community structure transitioned from chemotrophs (autotrophs) to heterotrophs [ 2 , 5 ]. In addition, Guo et al (2014) and Lathifah et al (2019) reported that successional change in the early soil microbial community occurred with primary vegetation that developed on the newly placed volcanic deposits, in which the plant benefit groups are mainly affiliated with the orders Burkholderiales and Rhizobiales, which are significantly increased with the vegetation succession [ 6 , 7 ]. Guo et al (2021) further revealed that different plant benefit groups dominated the rhizosphere in different developmental phases on the recent Miyake-jima volcanic deposits, i.e., Paraburkholderia and Trinickia represented the major plant-beneficial groups in the early colonization phase, whereas Rhizobiales and Arthrobacter increased in the later colonization phase [ 8 ].…”

Metagenomic analysis reveals rapid development of soil biota on fresh volcanic ash

“…Studies on developing volcanic ash soils have so far concentrated on chemical characterisation of the ash soils 4 – 7 or description of bacterial communities using only 16S rRNA gene sequencing 8 – 11 . There have been few studies of the functional aspects of the biota of developing ash soils.…”