Regoli
Francesco
Regoli
Francesco
No Thumbnail Available
Search Results
Now showing
1 - 2 of 2
-
ArticleDiversity and distribution of prokaryotes within a shallow-water pockmark field(Frontiers Media, 2016-06-17) Giovannelli, Donato ; d'Errico, Giuseppe ; Fiorentino, Federica ; Fattorini, Daniele ; Regoli, Francesco ; Angeletti, Lorenzo ; Bakran-Petricioli, Tatjana ; Vetriani, Costantino ; Yucel, Mustafa ; Taviani, Marco ; Manini, ElenaPockmarks are crater-like depression on the seafloor associated with hydrocarbon ascent through muddy sediments in continental shelves around the world. In this study, we examine the diversity and distribution of benthic microbial communities at shallow-water pockmarks adjacent to the Middle Adriatic Ridge. We integrate microbial diversity data with characterization of local hydrocarbons concentrations and sediment geochemistry. Our results suggest these pockmarks are enriched in sedimentary hydrocarbons, and host a microbial community dominated by Bacteria, even in deeper sediment layers. Pockmark sediments showed higher prokaryotic abundance and biomass than surrounding sediments, potentially due to the increased availability of organic matter and higher concentrations of hydrocarbons linked to pockmark activity. Prokaryotic diversity analyses showed that the microbial communities of these shallow-water pockmarks are unique, and comprised phylotypes associated with the cycling of sulfur and nitrate compounds, as well as numerous know hydrocarbon degraders. Altogether, this study suggests that shallow-water pockmark habitats enhance the diversity of the benthic prokaryotic biosphere by providing specialized environmental niches.
-
ArticleHelium, inorganic and organic carbon isotopes of fluids and gases across the Costa Rica convergent margin(Nature Research, 2019-11-25) Barry, Peter H. ; Nakagawa, Mayuko ; Giovannelli, Donato ; de Moor, J. Maarten ; Schrenk, Matthew O. ; Seltzer, Alan M. ; Manini, Elena ; Fattorini, Daniele ; di Carlo, Marta ; Regoli, Francesco ; Fullerton, Katherine ; Lloyd, Karen G.In 2017, fluid and gas samples were collected across the Costa Rican Arc. He and Ne isotopes, C isotopes as well as total organic and inorganic carbon concentrations were measured. The samples (n = 24) from 2017 are accompanied by (n = 17) samples collected in 2008, 2010 and 2012. He-isotopes ranged from arc-like (6.8 RA) to crustal (0.5 RA). Measured dissolved inorganic carbon (DIC) δ13CVPDB values varied from 3.55 to −21.57‰, with dissolved organic carbon (DOC) following the trends of DIC. Gas phase CO2 only occurs within ~20 km of the arc; δ13CVPDB values varied from −0.84 to −5.23‰. Onsite, pH, conductivity, temperature and dissolved oxygen (DO) were measured; pH ranged from 0.9–10.0, conductivity from 200–91,900 μS/cm, temperatures from 23–89 °C and DO from 2–84%. Data were used to develop a model which suggests that ~91 ± 4.0% of carbon released from the slab/mantle beneath the Costa Rican forearc is sequestered within the crust by calcite deposition with an additional 3.3 ± 1.3% incorporated into autotrophic biomass.