bcodmo_dataset_965250_v1 eng UTF8 dataset service Adam Shepherd BCO-DMO 508-289-2772 266 Woods Hole Rd. MS#36 Woods Hole MA 02543 USA erddap@bco-dmo.org pointOfContact 2026-04-16 ISO 19115-2 Geographic Information - Metadata Part 2 Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) 3 column row temporal [Cryptic CH4 Cycling] - Biogeochemical data on cryptic methane cycling in hypersaline sediments of the Carpinteria Salt Marsh Reserve, California from sampling in 2019 (Deciphering the Cryptic Cycling of Methane in Sediments of a Coastal Wetland) 2026-04-16 creation erddap.bco-dmo.org bcodmo_dataset_965250_v1 BCO-DMO info@bco-dmo.org https://osprey.bco-dmo.org/dataset/965250 information web browser Background Information Background information from the source information originator Methylotrophic methanogenesis occurring within sulfate-rich zones of coastal and marine sediments is functionally linked to anaerobic methane oxidation (AOM), together constituting a cryptic methane cycle. This investigation presents data on such cryptic methane cycling across a land-to-sea transect comprising four sampling sites within the Carpinteria Salt Marsh Reserve (CSMR) in southern California, USA: two brackish, one marine, and one hypersaline. Surface sediments (upper 20 cm) were examined using geochemical profiling and radiotracer incubation experiments employing 35S-labeled sulfate, 14C-labeled monomethylamine, and 14C-labeled methane.   Methane concentrations in sediment porewater were generally low (3–28 µM) across all sites, except at the marine station, where levels increased with depth, reaching up to 665 µM. Methane production from monomethylamine was detected throughout the depth profiles at all stations, with estimated rates ranging from sub-nanomolar to nanomolar per cubic centimeter of sediment per day. AOM, quantified via 14C-CH₄ tracer, co-occurred with methylotrophic methanogenesis at each station, exhibiting activity levels between 0.03 and 19.4 nmol cm⁻³ d⁻¹.   Porewater chemistry revealed elevated concentrations of sulfate and dissolved iron across all sites. Sulfate levels (9–91 mM) remained sufficiently high to support sulfate reduction, which showed activity levels from 1.5 to 2,506 nmol cm⁻³ d⁻¹. Vertical profiles of sulfide and Fe(II) suggested a geochemical shift along the transect—from iron-dominated reduction at the brackish stations to sulfate-dominated reduction at the marine and hypersaline stations. AOM activity overlapped with zones of sulfate reduction and Fe(II) enrichment, indicating that methane oxidation may be coupled to both sulfate and iron reduction across all sampling locations. BCO-DMO info@bco-dmo.org https://osprey.bco-dmo.org/dataset/965250 information web browser Background Information Background information from the source information pointOfContact earth science atmosphere ocean biosphere biology environment theme BCO-DMO project time latitude longitude theme CF The data may be used and redistributed for free but is not intended for legal use, since it may contain inaccuracies. Neither the data Contributor, ERD, NOAA, nor the United States Government, nor any of their employees or contractors, makes any warranty, express or implied, including warranties of merchantability and fitness for a particular purpose, or assumes any legal liability for the accuracy, completeness, or usefulness, of this information. BCO-DMO largerWorkCitation project eng geoscientificInformation 1 -119.5367 -119.5337 34.39873 34.40351 seconds 2019-07-09T16:00:00Z 2019-07-09T16:00:00Z [Cryptic CH4 Cycling] - Biogeochemical data on cryptic methane cycling in hypersaline sediments of the Carpinteria Salt Marsh Reserve, California from sampling in 2019 (Deciphering the Cryptic Cycling of Methane in Sediments of a Coastal Wetland) 2026-04-16 creation BCO-DMO info@bco-dmo.org https://osprey.bco-dmo.org/dataset/965250 information web browser Background Information Background information from the source information originator Methylotrophic methanogenesis occurring within sulfate-rich zones of coastal and marine sediments is functionally linked to anaerobic methane oxidation (AOM), together constituting a cryptic methane cycle. This investigation presents data on such cryptic methane cycling across a land-to-sea transect comprising four sampling sites within the Carpinteria Salt Marsh Reserve (CSMR) in southern California, USA: two brackish, one marine, and one hypersaline. Surface sediments (upper 20 cm) were examined using geochemical profiling and radiotracer incubation experiments employing 35S-labeled sulfate, 14C-labeled monomethylamine, and 14C-labeled methane.   Methane concentrations in sediment porewater were generally low (3–28 µM) across all sites, except at the marine station, where levels increased with depth, reaching up to 665 µM. Methane production from monomethylamine was detected throughout the depth profiles at all stations, with estimated rates ranging from sub-nanomolar to nanomolar per cubic centimeter of sediment per day. AOM, quantified via 14C-CH₄ tracer, co-occurred with methylotrophic methanogenesis at each station, exhibiting activity levels between 0.03 and 19.4 nmol cm⁻³ d⁻¹.   Porewater chemistry revealed elevated concentrations of sulfate and dissolved iron across all sites. Sulfate levels (9–91 mM) remained sufficiently high to support sulfate reduction, which showed activity levels from 1.5 to 2,506 nmol cm⁻³ d⁻¹. Vertical profiles of sulfide and Fe(II) suggested a geochemical shift along the transect—from iron-dominated reduction at the brackish stations to sulfate-dominated reduction at the marine and hypersaline stations. AOM activity overlapped with zones of sulfate reduction and Fe(II) enrichment, indicating that methane oxidation may be coupled to both sulfate and iron reduction across all sampling locations. ERDDAP tabledap 1 -119.5367 -119.5337 34.39873 34.40351 seconds 2019-07-09T16:00:00Z 2019-07-09T16:00:00Z tight ERDDAPtabledapDatasetQueryAndAccess https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_965250_v1 ERDDAP:tabledap ERDDAP-tabledap ERDDAP's tabledap service (a flavor of OPeNDAP) for tabular (sequence) data. Add different extensions (e.g., .html, .graph, .das, .dds) to the base URL for different purposes. download [Cryptic CH4 Cycling] - Biogeochemical data on cryptic methane cycling in hypersaline sediments of the Carpinteria Salt Marsh Reserve, California from sampling in 2019 (Deciphering the Cryptic Cycling of Methane in Sediments of a Coastal Wetland) 2026-04-16 creation BCO-DMO info@bco-dmo.org https://osprey.bco-dmo.org/dataset/965250 information web browser Background Information Background information from the source information originator Methylotrophic methanogenesis occurring within sulfate-rich zones of coastal and marine sediments is functionally linked to anaerobic methane oxidation (AOM), together constituting a cryptic methane cycle. This investigation presents data on such cryptic methane cycling across a land-to-sea transect comprising four sampling sites within the Carpinteria Salt Marsh Reserve (CSMR) in southern California, USA: two brackish, one marine, and one hypersaline. Surface sediments (upper 20 cm) were examined using geochemical profiling and radiotracer incubation experiments employing 35S-labeled sulfate, 14C-labeled monomethylamine, and 14C-labeled methane.   Methane concentrations in sediment porewater were generally low (3–28 µM) across all sites, except at the marine station, where levels increased with depth, reaching up to 665 µM. Methane production from monomethylamine was detected throughout the depth profiles at all stations, with estimated rates ranging from sub-nanomolar to nanomolar per cubic centimeter of sediment per day. AOM, quantified via 14C-CH₄ tracer, co-occurred with methylotrophic methanogenesis at each station, exhibiting activity levels between 0.03 and 19.4 nmol cm⁻³ d⁻¹.   Porewater chemistry revealed elevated concentrations of sulfate and dissolved iron across all sites. Sulfate levels (9–91 mM) remained sufficiently high to support sulfate reduction, which showed activity levels from 1.5 to 2,506 nmol cm⁻³ d⁻¹. Vertical profiles of sulfide and Fe(II) suggested a geochemical shift along the transect—from iron-dominated reduction at the brackish stations to sulfate-dominated reduction at the marine and hypersaline stations. AOM activity overlapped with zones of sulfate reduction and Fe(II) enrichment, indicating that methane oxidation may be coupled to both sulfate and iron reduction across all sampling locations. OPeNDAP 1 -119.5367 -119.5337 34.39873 34.40351 seconds 2019-07-09T16:00:00Z 2019-07-09T16:00:00Z tight OPeNDAPDatasetQueryAndAccess https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_965250_v1 OPeNDAP:OPeNDAP OPeNDAP An OPeNDAP service for tabular (sequence) data. Add different extensions (e.g., .html, .das, .dds) to the base URL for different purposes. download physicalMeasurement Date String Date Time_Local_PST String Time_local_pst Time_UTC String Time_utc time double Iso_datetime_utc Site_Name String Site_name Pushcore_Inner_Diameter float Pushcore_inner_diameter Sediment_Depth float Sediment_depth Porewater_Sulfate float Porewater_sulfate Salinity float Salinity Porewater_Iron_II float Porewater_iron_ii Porewater_Sulfide float Porewater_sulfide Porosity float Porosity Methane float Methane Sulfate_Reduction float Sulfate_reduction AOM_CH4 float Aom_ch4 AOM_MMA float Aom_mma MG_MMA float Mg_mma AOM_CH4_k float Aom_ch4_k AOM_MMA_k float Aom_mma_k MG_MMA_k float Mg_mma_k Adam Shepherd BCO-DMO 508-289-2772 266 Woods Hole Rd. MS#36 Woods Hole MA 02543 USA erddap@bco-dmo.org distributor OPeNDAP DAP/2.0 https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_965250_v1.html order Data Subset Form ERDDAP's version of the OPeNDAP .html web page for this dataset. Specify a subset of the dataset and download the data via OPeNDAP or in many different file types. download https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_965250_v1.graph order Make-A-Graph Form ERDDAP's Make-A-Graph .html web page for this dataset. Create an image with a map or graph of a subset of the data. mapDigital This record was created from dataset metadata by ERDDAP Version 2.22