Functional separation of colloids and gravitoids in surface waters based on differential settling velocity: Coupled cross-flow filtration-split flow thin-cell fractionation (CFF-SPLITT)

Content Provider	Semantic Scholar
Author	Gustafsson, Örjan Düker, Anders Larsson, Jenny Andersson, Per G. östa Ingri, Johan
Copyright Year	2000
Abstract	Given recognized challenges with shallow sediment trap and 234 Th-based particle flux studies, it behooves us to test the picture of surface ocean fluxes provided by such investigations with alternative and new analytical techniques. To this end, cross-flow filtration (CFF) has been coupled with split flow thin-cell fractionation (SPLITT) to afford active but mild separation of aquatic particles through a dynamic settling-velocity discrimination. Operation parameters have been developed to yield accurate settling-velocity cutoffs in the range .0.1‐. 10 md 21 , element recoveries in the range 85‐110%, and minimal influence of CFF preconcentration up to at least a factor 110. Chemical fingerprints of truly settling matter (i.e., gravitoids) in coastal waters provided by the CFF-SPLITT technique demonstrated that gravitoidal particles settling out of surface waters exhibit distinctly different composition than the bulk filterable particles. For instance, both gravitoidal POC and P belonged in a coastal Baltic regime largely to a slowly settling (1‐2 m d 21
Starting Page	1731
Ending Page	1742
Page Count	12
File Format	PDF HTM / HTML
Volume Number	45
Alternate Webpage(s)	http://usjgofs.whoi.edu/mzweb/scorwg116/orjan1.pdf
Alternate Webpage(s)	https://doi.org/10.4319/lo.2000.45.8.1731
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article