Échantillons de concentrations de chlorophylle et de phéopigment en vrac et en fractionnement de taille de l'Institut Hakai prélevées à l'aide de bouteilles Niskin, provisoire
10.21966/90h6-b497
Accès et utilisation
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Licence: Licence Creative Commons 4.0 Attribution
Limites: The utilized acidification method is sensitive to interference by high concentrations of chlorophyll c and b. High chlorophyll c concentrations can cause a slight overestimation of chlorophyll a and an underestimation of phaeopigments: negative phaeopigment concentrations can occur during bloom events with high chlorophyll c and healthy phytoplankton. High chlorophyll b concentrations can result in underestimations of chlorophyll a and overestimations of phaeopigments. When chlorophyll b is high relative to chlorophyll a, chlorophyll a can be underestimated by as much as 2.5 fold. For more details see Welschmeyer et al. (1994). These two types of interference likely had an influence on the published chlorophyll and phaeopigment dataset. Notably, comparison with HPLC has shown that stations in the Quadra Island region often experience conditions where chlorophyll b is present in high concentrations and is high relative to chlorophyll a. The acidification method used to analyze the Hakai Institute dataset has been shown to highly overestimate phaeopigment concentrations based on comparison to concentrations determined by HPLC (Trees et al., 2003). Care should be used when interpreting the published phaeopigment concentrations. Prior to 2021, samples that exceeded the manufacturer specified instrument sensitivity range were not diluted to bring their concentrations within the specified range. Samples run above the instrument sensitivity range may have underestimated chlorophyll concentrations due to the blockage of light passing through the sample and a corresponding reduction of fluorescence output (see Turner Trilogy user manual for complete description). Comparison with matching HPLC derived chlorophyll a suggests that the affected samples may be useable, but further analysis is required. This provisional dataset includes these data. Prior to 2018, annual calibrations of the Hakai Institute Turner Trilogy benchtop fluorometers showed variability in the calibration slopes and acid ratios that were applied to the data. The inconsistent nature of this variability suggests error due to analytical methods rather than instrument drift. As a result, the chlorophyll and phaeopigment concentrations of the data where these calibrations were applied may have error as high as +/- 12 % from this source alone. These data have been included in this provisional dataset. Prior to 2018, QA/QC analysis suggests potential influence by acid contamination on the chlorophyll and phaeopigment concentrations (i.e. very low chlorophyll a and high phaeopigment concentrations where the CTD fluorometer and HPLC showed high chlorophyll a). In 2018, methodological controls were put in place to limit acid contamination and the issue ceased. Care has been taken to flag the contaminated data, but data with less obvious contamination effects may not have been captured by QA/QC and may be present in this provisional dataset. This provisional dataset includes all data flagged as "suspicious" (show suspicious trends, but may not be incorrect), but excludes data flagged as "discard" (clearly erroneous). |
Données et ressources
Citation
Étendue du jeu de données
Dates
| Date(s) de référence des métadonnées | July 12, 2024 (Publication) July 12, 2024 (Revision) |
|---|---|
| Date(s) de référence des données | July 10, 2014 (Création) January 13, 2022 (Publication) |
| Fréquence de mise à jour | Au besoin |
Contacts
- Affiliation
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Hakai Institute
- Rôle
- Distributeur
- Propriétaire
- Éditeur
- Nom
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Del Bel Belluz, Justin
- Affiliation
-
Hakai Institute
- Courriel
- justin.belluz@hakai.org
- Rôle
- Auteur
- Dépositaire
- Initiateur
- Point de contact
- Chercheur principal
- Éditeur
- Fournisseur de ressources
- Nom
- Fedje, Bryn
- Affiliation
-
Hakai Institute
- Courriel
- bryn.fedje@hakai.org
- Rôle
- Dépositaire
- transformateur
- Éditeur
- Contributeur
- Affiliation
-
Tula Foundation
- Rôle
- Fondateur
Info additionnelle
| Champ | Valeur |
|---|---|
| Variables océaniques | Matière particulaire |
| Portée | Jeu de données |
| Statut | En cours |
| Note de maintenance | Generated from https://hakaiinstitute.github.io/hakai-metadata-entry-form#/en/hakai/7U7b8oPpeTN6gjvXlUCTGJr5pga2/-McQFPAf457LB4-SWmyL |
| Étendue spatiale | { "coordinates": [ [ [ -128.5, 52.27 ], [ -127.4, 52.21 ], [ -127.2, 51.66 ], [ -125.6, 51.13 ], [ -124.8, 50.96 ], [ -124.1, 50.43 ], [ -124.7, 49.98 ], [ -124.9, 49.8 ], [ -126.7, 50.45 ], [ -128.1, 51.37 ], [ -128.4, 51.69 ], [ -128.5, 52.27 ] ] ], "type": "Polygon" } |
| Latitude limite Nord | 49.8 |
| Latitude limite Sud | 52.27 |
| Longitude limite Est | -124.1 |
| Longitude limite Ouest | -128.5 |
| Étendue temporelle |
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| Étendue verticale |
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| Langue par défaut | Anglais |
| Identifiant de citation |
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| Projects |
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| Included in Data Catalogue |
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