Geobiology最新文献

{"title":"Comprehensive molecular-isotopic characterization of archaeal lipids in the Black Sea water column and underlying sediments","authors":"Qing-Zeng Zhu,&nbsp;Marcus Elvert,&nbsp;Travis B. Meador,&nbsp;Jan M. Schröder,&nbsp;Katiana D. Doeana,&nbsp;Kevin W. Becker,&nbsp;Felix J. Elling,&nbsp;Julius S. Lipp,&nbsp;Verena B. Heuer,&nbsp;Matthias Zabel,&nbsp;Kai-Uwe Hinrichs","doi":"10.1111/gbi.12589","DOIUrl":"10.1111/gbi.12589","url":null,"abstract":"<p>The Black Sea is a permanently anoxic, marine basin serving as model system for the deposition of organic-rich sediments in a highly stratified ocean. In such systems, archaeal lipids are widely used as paleoceanographic and biogeochemical proxies; however, the diverse planktonic and benthic sources as well as their potentially distinct diagenetic fate may complicate their application. To track the flux of archaeal lipids and to constrain their sources and turnover, we quantitatively examined the distributions and stable carbon isotopic compositions (δ¹³C) of intact polar lipids (IPLs) and core lipids (CLs) from the upper oxic water column into the underlying sediments, reaching deposits from the last glacial. The distribution of IPLs responded more sensitively to the geochemical zonation than the CLs, with the latter being governed by the deposition from the chemocline. The isotopic composition of archaeal lipids indicates CLs and IPLs in the deep anoxic water column have negligible influence on the sedimentary pool. Archaeol substitutes tetraether lipids as the most abundant IPL in the deep anoxic water column and the lacustrine methanic zone. Its elevated IPL/CL ratios and negative δ¹³C values indicate active methane metabolism. Sedimentary CL- and IPL-crenarchaeol were exclusively derived from the water column, as indicated by non-variable δ¹³C values that are identical to those in the chemocline and by the low BIT (branched isoprenoid tetraether index). By contrast, in situ production accounts on average for 22% of the sedimentary IPL-GDGT-0 (glycerol dibiphytanyl glycerol tetraether) based on isotopic mass balance using the fermentation product lactate as an endmember for the dissolved substrate pool. Despite the structural similarity, glycosidic crenarchaeol appears to be more recalcitrant in comparison to its non-cycloalkylated counterpart GDGT-0, as indicated by its consistently higher IPL/CL ratio in sediments. The higher TEX₈₆, CCaT, and GDGT-2/-3 values in glacial sediments could plausibly result from selective turnover of archaeal lipids and/or an archaeal ecology shift during the transition from the glacial lacustrine to the Holocene marine setting. Our in-depth molecular-isotopic examination of archaeal core and intact polar lipids provided new constraints on the sources and fate of archaeal lipids and their applicability in paleoceanographic and biogeochemical studies.</p>","PeriodicalId":173,"journal":{"name":"Geobiology","volume":"22 2","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/gbi.12589","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140093080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Groundwater microbial communities reflect geothermal activity on volcanic island","authors":"Sheree J. Watson,&nbsp;Cédric Arisdakessian,&nbsp;Maria Petelo,&nbsp;Kekuʻiapōiula Keliipuleole,&nbsp;Diamond K. Tachera,&nbsp;Brytne K. Okuhata,&nbsp;Kiana L. Frank","doi":"10.1111/gbi.12591","DOIUrl":"10.1111/gbi.12591","url":null,"abstract":"<p>Studies of the effects of volcanic activity on the Hawaiian Islands are extremely relevant due to the past and current co-eruptions at both Mauna Loa and Kīlauea. The Big Island of Hawaiʻi is one of the most seismically monitored volcanic systems in the world, and recent investigations of the Big Island suggest a widespread subsurface connectivity between volcanoes. Volcanic activity has the potential to add mineral contaminants into groundwater ecosystems, thus affecting water quality, and making inhabitants of volcanic islands particularly vulnerable due to dependence on groundwater aquifers. As part of an interdisciplinary study on groundwater aquifers in Kona, Hawaiʻi, over 40 groundwater wells were sampled quarterly from August 2017 through March 2019, before and after the destructive eruption of the Kīlauea East Rift Zone in May 2018. Sample sites occurred at great distance (~80 km) from Kīlauea, allowing us to pose questions of how volcanic groundwater aquifers might be influenced by volcanic subsurface activity. Approximately 400 water samples were analyzed and temporally split by pre-eruption and post-eruption for biogeochemical analysis. While most geochemical constituents did not differ across quarterly sampling, microbial communities varied temporally (pre- and post-eruption). When a salinity threshold amongst samples was set, the greatest microbial community differences were observed in the freshest groundwater samples. Differential analysis indicated bacterial families with sulfur (S) metabolisms (sulfate reducers, sulfide oxidation, and disproportionation of S-intermediates) were enriched post-eruption. The diversity in S-cyclers without a corresponding change in sulfate geochemistry suggests cryptic cycling may occur in groundwater aquifers as a result of distant volcanic subsurface activity. Microbial communities, including taxa that cycle S, may be superior tracers to changes in groundwater quality, especially from direct inputs of subsurface volcanic activity.</p>","PeriodicalId":173,"journal":{"name":"Geobiology","volume":"22 2","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140064493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrogeological controls on microbial activity and habitability in the Precambrian continental crust","authors":"Min Song,&nbsp;Oliver Warr,&nbsp;Jon Telling,&nbsp;Barbara Sherwood Lollar","doi":"10.1111/gbi.12592","DOIUrl":"10.1111/gbi.12592","url":null,"abstract":"<p>Earth's deep continental subsurface is a prime setting to study the limits of life's relationship with environmental conditions and habitability. In Precambrian crystalline rocks worldwide, deep ancient groundwaters in fracture networks are typically oligotrophic, highly saline, and locally inhabited by low-biomass communities in which chemolithotrophic microorganisms may dominate. Periodic opening of new fractures can lead to penetration of surface water and/or migration of fracture fluids, both of which may trigger changes in subsurface microbial composition and activity. These hydrogeological processes and their impacts on subsurface communities may play a significant role in global cycles of key elements in the crust. However, to date, considerable uncertainty remains on how subsurface microbial communities may respond to these changes in hydrogeochemical conditions. To address this uncertainty, the biogeochemistry of Thompson mine (Manitoba, Canada) was investigated. Compositional and isotopic analyses of fracture waters collected here at ~1 km below land surface revealed different extents of mixing between subsurface brine and (paleo)meteoric waters. To investigate the effects this mixing may have had on microbial communities, the Most Probable Number technique was applied to test community response for a total of 13 different metabolisms. The results showed that all fracture waters were dominated by viable heterotrophic microorganisms which can utilize organic materials associated with aerobic/facultative anaerobic processes, sulfate reduction, or fermentation. Where mixing between subsurface brines and (paleo)meteoric waters occurs, the communities demonstrate higher cell densities and increased viable functional potentials, compared to the most saline sample. This study therefore highlights the connection between hydrogeologic heterogeneity and the heterogeneity of subsurface ecosystems in the crystalline rocks, and suggests that hydrogeology can have a considerable impact on the scope and scale of subsurface microbial communities on Earth and potentially beyond.</p>","PeriodicalId":173,"journal":{"name":"Geobiology","volume":"22 2","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/gbi.12592","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140038395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Featured Cover","authors":"","doi":"10.1111/gbi.12588","DOIUrl":"https://doi.org/10.1111/gbi.12588","url":null,"abstract":"<p><b>Cover</b></p><p>The cover image is based on the Research Article <i>Distinctive microfossil supports early Paleoproterozoic rise in complex cellular organization</i> by Erica V. Barlow et al., https://doi.org/10.1111/gbi.12576\u0000 \u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure>\u0000 </p>","PeriodicalId":173,"journal":{"name":"Geobiology","volume":"22 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/gbi.12588","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139716811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular and mineral responses of corals grown under artificial Calcite Sea conditions","authors":"Nicola Conci,&nbsp;Erika Griesshaber,&nbsp;Ramón E. Rivera-Vicéns,&nbsp;Wolfgang W. Schmahl,&nbsp;Sergio Vargas,&nbsp;Gert Wörheide","doi":"10.1111/gbi.12586","DOIUrl":"10.1111/gbi.12586","url":null,"abstract":"<p>The formation of skeletal structures composed of different calcium carbonate polymorphs (e.g. aragonite and calcite) appears to be both biologically and environmentally regulated. Among environmental factors influencing aragonite and calcite precipitation, changes in seawater conditions—primarily in the molar ratio of magnesium and calcium during so-called ‘Calcite’ (<i>m</i>Mg:<i>m</i>Ca below 2) or ‘Aragonite’ seas (<i>m</i>Mg:<i>m</i>Ca above 2)—have had profound impacts on the distribution and performance of marine calcifiers throughout Earth's history. Nonetheless, the fossil record shows that some species appear to have counteracted such changes and kept their skeleton polymorph unaltered. Here, the aragonitic octocoral <i>Heliopora coerulea</i> and the aragonitic scleractinian <i>Montipora digitata</i> were exposed to Calcite Sea-like <i>m</i>Mg:<i>m</i>Ca with various levels of magnesium and calcium concentration, and changes in both the mineralogy (i.e. CaCO₃ polymorph) and gene expression were monitored. Both species maintained aragonite deposition at lower <i>m</i>Mg:<i>m</i>Ca ratios, while concurrent calcite presence was only detected in <i>M. digitata</i>. Despite a strong variability between independent experimental replicates for both species, the expression for a set of putative calcification-related genes, including known components of the <i>M. digitata</i> skeleton organic matrix (SkOM), was found to consistently change at lower <i>m</i>Mg:<i>m</i>Ca. These results support the previously proposed involvements of the SkOM in counteracting decreases in seawater <i>m</i>Mg:<i>m</i>Ca. Although no consistent expression changes in calcium and magnesium transporters were observed, down-regulation calcium channels in <i>H. coerulea</i> in one experimental replicate and at an <i>m</i>Mg:<i>m</i>Ca of 2.5, pointing to a possible active calcium uptake regulation by the corals under altered <i>m</i>Mg:<i>m</i>Ca.</p>","PeriodicalId":173,"journal":{"name":"Geobiology","volume":"22 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/gbi.12586","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139665956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dissolved silica affects the bulk iron redox state and recrystallization of minerals generated by photoferrotrophy in a simulated Archean ocean","authors":"Alice Zhou,&nbsp;Alexis S. Templeton,&nbsp;Jena E. Johnson","doi":"10.1111/gbi.12587","DOIUrl":"https://doi.org/10.1111/gbi.12587","url":null,"abstract":"<p>Chemical sedimentary deposits called Banded Iron Formations (BIFs) are one of the best surviving records of ancient marine (bio)geochemistry. Many BIF precursor sediments precipitated from ferruginous, silica-rich waters prior to the Great Oxidation Event at ~2.43 Ga. Reconstructing the mineralogy of BIF precursor phases is key to understanding the coevolution of seawater chemistry and early life. Many models of BIF deposition invoke the activity of Fe(II)-oxidizing photoautotrophic bacteria as a mechanism for precipitating mixed-valence Fe(II,III) and/or fully oxidized Fe(III) minerals in the absence of molecular oxygen. Although the identity of phases produced by ancient photoferrotrophs remains debated, laboratory experiments provide a means to explore what their mineral byproducts might have been. Few studies have thoroughly characterized precipitates produced by photoferrotrophs in settings representative of Archean oceans, including investigating how residual Fe(II)_aq can affect the mineralogy of expected solid phases. The concentration of dissolved silica (Si) is also an important variable to consider, as silicate species may influence the identity and reactivity of Fe(III)-bearing phases. To address these uncertainties, we cultured <i>Rhodopseudomonas palustris</i> TIE-1 as a photoferrotroph in synthetic Archean seawater with an initial [Fe(II)_aq] of 1 mM and [Si] spanning 0–1.5 mM. Ferrihydrite was the dominant precipitate across all Si concentrations, even with substantial Fe(II) remaining in solution. Consistent with other studies of microbial iron oxidation, no Fe-silicates were observed across the silica gradient, although Si coprecipitated with ferrihydrite via surface adsorption. More crystalline phases such as lepidocrocite and goethite were only detected at low [Si] and are likely products of Fe(II)-catalyzed ferrihydrite transformation. Finally, we observed a substantial fraction of Fe(II) in precipitates, with the proportion of Fe(II) increasing as a function of [Si]. These experimental results suggest that photoferrotrophy in a Fe(II)-buffered ocean may have exported Fe(II,III)-oxide/silica admixtures to BIF sediments, providing a more chemically diverse substrate than previously hypothesized.</p>","PeriodicalId":173,"journal":{"name":"Geobiology","volume":"22 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/gbi.12587","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139655306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enameloid-bound δ15N reveals large trophic separation among Late Cretaceous sharks in the northern Gulf of Mexico","authors":"Chelsea M. Comans,&nbsp;Sandi M. Smart,&nbsp;Emma R. Kast,&nbsp;YueHan Lu,&nbsp;Tina Lüdecke,&nbsp;Jennifer N. Leichliter,&nbsp;Daniel M. Sigman,&nbsp;Takehito Ikejiri,&nbsp;Alfredo Martínez-García","doi":"10.1111/gbi.12585","DOIUrl":"https://doi.org/10.1111/gbi.12585","url":null,"abstract":"<p>The nitrogen isotopic composition (¹⁵N/¹⁴N ratio, or δ¹⁵N) of enameloid-bound organic matter (δ¹⁵N_EB) in shark teeth was recently developed to investigate the biogeochemistry and trophic structures (i.e., food webs) of the ancient ocean. Using δ¹⁵N_EB, we present the first nitrogen isotopic evidence for trophic differences between shark taxa from a single fossil locality. We analyze the teeth of four taxa (<i>Meristodonoides</i>, <i>Ptychodus</i>, <i>Scapanorhynchus</i>, and <i>Squalicorax</i>) from the Late Cretaceous (83–84 Ma) Trussells Creek site in Alabama, USA, and compare the N isotopic findings with predictions from tooth morphology, the traditional method for inferring shark paleo-diets. Our δ¹⁵N_EB data indicate two distinct trophic groups, with averages separated by 6.1 ± 2.1‰. The lower group consists of <i>Meristodonoides</i> and <i>Ptychodus,</i> and the higher group consists of <i>Scapanorhynchus</i> and <i>Squalicorax</i> (i.e., lamniforms). This δ¹⁵N_EB difference indicates a 1.5 ± 0.5 trophic-level separation between the two groups, a finding that is in line with paleontological predictions of a higher trophic level for these lamniforms over <i>Meristodonoides</i> and <i>Ptychodus</i>. However, the δ¹⁵N_EB of <i>Meristodonoides</i> is lower than suggested by tooth morphology, although consistent with mechanical tests suggesting that higher trophic-level bony fishes were not a major component of their diet. Further, δ¹⁵N_EB indicates that the two sampled lamniform taxa fed at similar trophic levels despite their different inferred tooth functions. These two findings suggest that tooth morphology alone may not always be a sufficient indicator of dietary niche. The large trophic separation revealed by the δ¹⁵N_EB offset leaves open the possibility that higher trophic-level lamniforms, such as those measured here, preyed upon smaller, lower trophic-level sharks like <i>Meristodonoides</i>.</p>","PeriodicalId":173,"journal":{"name":"Geobiology","volume":"22 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/gbi.12585","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139655310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The illusion of balance in the history of the biosphere","authors":"Geerat J. Vermeij","doi":"10.1111/gbi.12584","DOIUrl":"https://doi.org/10.1111/gbi.12584","url":null,"abstract":"<p>Earth's surface has been irreversibly altered by the activity of organisms, a process that has accelerated as the power of the biosphere (the rate at which life extracts and deploys energy) has increased over time. This trend is incompatible with the expectation that the inputs to Earth's surface of life's materials from the crust and mantle be matched by export from Earth's surface to long-term reservoirs. Here, I suggest that the collective activity of organisms has always violated this balance. The biosphere's ability to extract, retain, recycle, and accumulate materials has allowed living biomass to increase and for exports to decrease over very long timescales. This collective metabolism implies a net transfer of materials from the planet's interior to its surface. The combination of metabolic innovations, competition, adaptive evolution, and the establishment of collaborative economic feedback in ecosystems created dynamic ecological stability despite great spatial and temporal heterogeneity in physical and biological inputs and export of nutrients into and out of the biosphere. Models of geochemical cycling must take the fundamental role of living organisms and the evolutionary changes in these roles into account to explain past and future conditions.</p>","PeriodicalId":173,"journal":{"name":"Geobiology","volume":"22 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139435232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New keratose sponges after the end-Permian extinction provide insights into biotic recoveries","authors":"Siqi Wu,&nbsp;Joachim Reitner,&nbsp;David A. T. Harper,&nbsp;Jianxin Yu,&nbsp;Zhong-Qiang Chen","doi":"10.1111/gbi.12582","DOIUrl":"10.1111/gbi.12582","url":null,"abstract":"<p>We challenge the prevailing view that the end-Permian extinction impeded the Triassic evolution of sponges. Here, we report a deep-water community dominated by abundant keratose sponges in the lowest Triassic strata from Southwest China. The sponge fossils occur as dark elliptical imprints in mudstone with distinct oscula on their tops. The structure of preserved fibers suggests closest affinity with the extant Dictyoceratida, an aspiculate demosponge. The exceptional preservation plays a crucial role in retaining their exquisite structures. Sedimentary, taphonomic, pyrite framboid, and trace elemental analyses indicate that the sponges proliferated in an oxygen-poor habitat, demonstrating the high tolerance of sponges to severe conditions. Sponge proliferation is a signal of environmental upheaval but they also stabilized the ecosystem, driving the first phase of biotic recovery after the end-Permian extinction.</p>","PeriodicalId":173,"journal":{"name":"Geobiology","volume":"22 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139054618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deep subsurface microbial life in impact-altered Late Paleozoic granitoid rocks from the Chicxulub impact crater","authors":"Sohaib Naseer Quraish,&nbsp;Charles Cockell,&nbsp;Cornelia Wuchter,&nbsp;David Kring,&nbsp;Kliti Grice,&nbsp;Marco J. L. Coolen","doi":"10.1111/gbi.12583","DOIUrl":"10.1111/gbi.12583","url":null,"abstract":"<p>In 2016, IODP-ICDP Expedition 364 recovered an 829-meter-long core within the peak ring of the Chicxulub impact crater (Yucatán, Mexico), allowing us to investigate the post-impact recovery of the heat-sterilized deep continental microbial biosphere at the impact site. We recently reported increased cell biomass in the impact suevite, which was deposited within the first few hours of the Cenozoic, and that the overall microbial communities differed significantly between the suevite and the other main core lithologies (i.e., the granitic basement and the overlying Early Eocene marine sediments; Cockell et al., 2021). However, only seven rock intervals were previously analyzed from the geologically heterogenic and impact-deformed 587-m-long granitic core section below the suevite interval. Here, we used 16S rRNA gene profiling to study the microbial community composition in 45 intervals including (a) 31 impact-shocked granites, (b) 7 non-granitic rocks (i.e., consisting of suevite and impact melt rocks intercalated into the granites during crater formation and strongly serpentinized pre-impact sub-volcanic, ultramafic basanite/dolerite), and (c) 7 cross-cut mineral veins of anhydride and silica. Most recovered microbial taxa resemble those found in hydrothermal systems. Spearman correlation analysis confirmed that the borehole temperature, which gradually increased from 47 to 69°C with core depth, significantly shaped a subset of the vertically stratified modern microbial community composition in the granitic basement rocks. However, bacterial communities differed significantly between the impoverished shattered granites and nutrient-enriched non-granite rocks, even though both lithologies were at similar depths and temperatures. Furthermore, Spearman analysis revealed a strong correlation between the microbial communities and bioavailable chemical compounds and suggests the presence of chemolithoautotrophs, which most likely still play an active role in metal and sulfur cycling. These results indicate that post-impact microbial niche separation has also occurred in the granitic basement lithologies, as previously shown for the newly formed lithologies. Moreover, our data suggest that the impact-induced geochemical boundaries continue to shape the modern-day deep biosphere in the granitic basement underlying the Chicxulub crater.</p>","PeriodicalId":173,"journal":{"name":"Geobiology","volume":"22 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/gbi.12583","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139054849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}