Title :

Optimization and quality control of suspended particulate matter concentration measurement using turbidity measurements

Author(s) :

Neukermans, Griet [Auteur]
Université du Littoral Côte d'Opale [ULCO]
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]
Ruddick, K. [Auteur]
Loisel, Hubert [Auteur]
Université du Littoral Côte d'Opale [ULCO]
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]
Roose, Patrick [Auteur]

Journal title :

Limnology and Oceanography

Pages :

1011-1023

Publisher :

Association for the Sciences of Limnology and Oceanography

Publication date :

2012-12

ISSN :

0024-3590

HAL domain(s) :

Planète et Univers [physics]/Sciences de la Terre/Océanographie

English abstract : [en]

The dry weight concentration of suspended particulate material, [SPM] (units: mg L-1), is measured by passing a known volume of seawater through a preweighed filter and reweighing the filter after drying. This is apparently ...
Show more >The dry weight concentration of suspended particulate material, [SPM] (units: mg L-1), is measured by passing a known volume of seawater through a preweighed filter and reweighing the filter after drying. This is apparently a simple procedure, but accuracy and precision of [SPM] measurements vary widely depending on the measurement protocol and experience and skills of the person filtering. We show that measurements of turbidity, T (units: FNU), which are low cost, simple, and fast, can be used to optimally set the filtration volume, to detect problems with the mixing of the sample during subsampling, and to quality control [SPM]. A relationship between T and 'optimal filtration volume', Vopt, is established where Vopt is the volume at which enough matter is retained by the filter for precise measurement, but not so much that the filter clogs. This relationship is based on an assessment of procedural uncertainties in the [SPM] measurement protocol, including salt retention, filter preparation, weighing, and handling, and on a value for minimum relative precision for replicates. The effect of filtration volume on the precision of [SPM] measurement is investigated by filtering volumes of seawater ranging between one fifth and twice Vopt. It is shown that filtrations at Vopt maximize precision and cost effectiveness of [SPM]. Finally, the 90% prediction bounds of the T versus [SPM] regression allow the quality control of [SPM] determinations. In conclusion it is recommended that existing [SPM] gravimetric measurements be refined to include measurement of turbidity to improve their precision and quality control.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Internationale

Popular science :

Non

Collections :

• Laboratoire d'Océanologie et de Géosciences (LOG) - UMR 8187

Source :

Harvested from HAL