dc.contributor.author | Nehir, Münevver | |
dc.contributor.author | Esposito, Mario | |
dc.contributor.author | Begler, Christian | |
dc.contributor.author | Frank, Carsten | |
dc.contributor.author | Zielinski, Oliver | |
dc.contributor.author | Achterberg, Eric P. | |
dc.date.accessioned | 2021-07-18T00:06:53Z | |
dc.date.available | 2021-07-18T00:06:53Z | |
dc.date.issued | 2021 | |
dc.identifier.citation | Nehir, M., Esposito, M., Begler, C.,
Frank, C., Zielinski, O. and
Achterberg, E.P. (2021) Improved
Calibration and Data Processing
Procedures of OPUS Optical Sensor
for High-Resolution in situ Monitoring
of Nitrate in Seawater.
Frontiers in Marine Scence, 8:663800, 15pp.
DOI: 10.3389/fmars.2021.663800 | en_US |
dc.identifier.uri | https://repository.oceanbestpractices.org/handle/11329/1626 | |
dc.identifier.uri | http://dx.doi.org/10.25607/OBP-1558 | |
dc.description.abstract | Nitrate, an essential nutrient for primary production in natural waters, is optically
detectable in the ultraviolet spectral region of 217–240 nm, with no chemical reagents
required. Optical nitrate sensors allow monitoring at high temporal and spatial
resolutions that are difficult to achieve with traditional approaches involving collection
of discrete water samples followed by wet-chemical laboratory analysis. The optical
nitrate measurements are however subject to matrix interferences in seawater, including
bromide, at the spectral range of interest. Significant progress has been made over
the last 10 years in improving data quality for seawater nitrate analysis using the ISUS
and SUNA (Seabird Scientific, United States) optical sensors. Standardization of sensor
calibration and data processing procedures are important for ensuring comparability
of marine nitrate data reported in different studies. Here, we improved the calibration
and data processing of the OPUS sensor (TriOS GmbH, Germany), and tested five
OPUS sensors simultaneously deployed under identical conditions in the laboratory
in terms of inter-sensor similarities and differences. We also improved the sampling
interval of the OPUS to 3 s in a continuous mode by a custom-built controller, which
facilitates the integration of the sensor into autonomous profiling systems. Real-time,
high-resolution, in situ measurements were conducted through (1) underway surface
measurements in the southeastern North Sea and (2) depth profiles on a conductivity–
temperature–depth frame in the tropical Atlantic Ocean. The nitrate data computed from
the optical measurements of the sensor agreed with data from discrete water samples
analyzed via conventional wet-chemical methods. This work demonstrates that the
OPUS sensor, with improved calibration and data processing procedures, allows in situ
quantification of nitrate concentrations in dynamic coastal waters and the open ocean,
with an accuracy better than 2 mM and short-term precision of 0.4 mM NO3-. The
OPUS has a unique depth rating of 6,000 m and is a good and cost-effective nitrate
sensor for the research community. | en_US |
dc.language.iso | en | en_US |
dc.rights | Attribution 3.0 United States | * |
dc.rights.uri | http://creativecommons.org/licenses/by/3.0/us/ | * |
dc.subject.other | Nitrate | en_US |
dc.subject.other | Optial sensor | en_US |
dc.subject.other | In situ spectrophotometer | en_US |
dc.subject.other | Ultraviolet spectrophotometer | en_US |
dc.subject.other | Autonomous monitoring | en_US |
dc.title | Improved Calibration and Data Processing Procedures of OPUS Optical Sensor for High-Resolution in situ Monitoring of Nitrate in Seawater. | en_US |
dc.type | Journal Contribution | en_US |
dc.description.notes | , | en_US |
dc.description.refereed | Refereed | en_US |
dc.format.pagerange | 15pp. | en_US |
dc.identifier.doi | 10.3389/fmars.2021.663800 | |
dc.subject.parameterDiscipline | Nutrients | en_US |
dc.subject.instrumentType | nutrient analysers | en_US |
dc.subject.dmProcesses | Data acquisition | en_US |
dc.subject.dmProcesses | Data processing | en_US |
dc.bibliographicCitation.title | Frontiers in Marine Science | en_US |
dc.bibliographicCitation.volume | 8. | en_US |
dc.bibliographicCitation.issue | Article 663800 | en_US |
dc.description.sdg | 14.a | en_US |
dc.description.eov | Nutrients | en_US |
dc.description.frontiers | 2021-07-05 | |
dc.description.adoption | Validated (tested by third parties) | en_US |
dc.description.supportingotherVariables | Nitrate | en_US |
dc.description.sensors | Optical sensor, Seabird | en_US |
dc.description.methodologyType | Method | en_US |
dc.description.methodologyType | Description of a metrology standard | en_US |
dc.description.methodologyType | Reports with methodological relevance | en_US |
obps.contact.contactname | Münevver Nehir | |
obps.contact.contactemail | mnehir@web.de | |
obps.resourceurl.publisher | https://www.frontiersin.org/articles/10.3389/fmars.2021.663800/full | |