Global diversity of microbial communities in marine sediment

Abstract

Microbial life in marine sediment contributes substantially to global biomass and is a crucial component of the Earth system. Subseafloor sediment includes both aerobic and anaerobic microbial ecosystems, which persist on very low fluxes of bioavailable energy over geologic time. However, the taxonomic diversity of the marine sedimentary microbial biome and the spatial distribution of that diversity have been poorly constrained on a global scale. We investigated 299 globally distributed sediment core samples from 40 different sites at depths of 0.1 to 678 m below the seafloor. We obtained ∼47 million 16S ribosomal RNA (rRNA) gene sequences using consistent clean subsampling and experimental procedures, which enabled accurate and unbiased comparison of all samples. Statistical analysis reveals significant correlations between taxonomic composition, sedimentary organic carbon concentration, and presence or absence of dissolved oxygen. Extrapolation with two fitted species–area relationship models indicates taxonomic richness in marine sediment to be 7.85 × 103 to 6.10 × 105 and 3.28 × 104 to 2.46 × 106 amplicon sequence variants for Archaea and Bacteria, respectively. This richness is comparable to the richness in topsoil and the richness in seawater, indicating that Bacteria are more diverse than Archaea in Earth’s global biosphere.

Bacteria From the Southern Gulf of Mexico: Baseline, Diversity, Hydrocarbon-Degrading Potential and Future Applications

“…The superficial sediments (≤ 10 centimeters in depth) were collected using a box corer (Figure 2). The observed taxonomy was diverse, as previously reported (Hoshino et al, 2020); however, similar to sediments from oil-polluted sites (Head et al, 2006), hydrocarbon degraders were also abundant in our samples. Sequencing reflects the presence of bacteria and archaea; however, because we were focused on collecting bacteria, the relative abundance was greater.…”

Microbial diversity in tropical marine sediments assessed using culture-dependent and culture-independent techniques

“…This indicates that relatively deep sequencing is needed to capture the microbial diversity present in these complex communities. A recent study comparing global diversity of marine sediments detected over 34,000 ASVs associated with bacteria and archaea across 299 sites (Hoshino et al, 2020). In total, our study found over 27,000 ASVs from CD and CI samples around Carrie Bow Cay, Belize.…”

Recovery of high-qualitied Genomes from a deep-inland Salt Lake Using BASALT

“…Lokiarchaeota belongs to a recently discovered superphylum Asgardarchaeota, which is a hot topic linked to the origin of eukaryotes (Spang et al 2018). To date, candidate species of Lokiarchaeota were universally found near deep sea hydrothermal vents and marine sediments (Spang et al 2015, Spang et al 2018, Hoshino et al 2020, Wong et al 2020, Yin et al 2020). A recent study has found candidate Lokiarchaeota present in hypersaline lakes near Black Sea (Bulzu et al 2019), whereas our study highlighted the first time that Loki-2 species were found from deep-inland hypersaline lake sediments.…”

“…As such environmental parameters (physical, chemical and biological) have direct and indirect effect on microbial communities (Berdjeb et al 2011, Nishiyama et al 2018, Easson and Lopez 2019, Glasl et al 2019), exploring uncommon environment can expand the breadth of our understanding on microbial diversity and potential functions. A few studies have already launched targeting rarely explored environments on deserts (Finstad et al 2017), oil fields (Eze et al 2020), hydrothermal vents (Anderson et al 2017) and non-marine soda lakes (Vavourakis et al 2018), but such number of investigations were still scarce to support the expansion of microbial diversity, compare to a vast majority of studies on marine, soil and human-associated microbiomes (Hoshino et al 2020, Nascimento Lemos et al 2020, Almeida et al 2021).…”