Compositional Heterogeneity Within Oceanic POM: A Study Using Flow Cytometry and Mass Spectrometry
Abstract
This thesis applied direct temperature-resolved mass spectrometry (DT-MS), flow cytometry, and multivariate statistics to the study of marine particulate organic matter (POM) collected from the North Atlantic. DT-MS is a rapid and sensitive molecular-level analytical technique. The fact that DT-MS only requires microgram quantities of sample permits the coupling of DT-MS and preparative flow cytometry. Flow cytometry was used here to isolate "phytoplankton" and "detritus" in 2 to 53 microns POM. The molecular-level differences between and within small-particle POM (<53 microns), large-particle POM (>53 microns), "phytoplankton" and "detritus" were explored using DT-MS and discriminant analysis. As the polysaccharide composition of POM subclasses was a major source of variation, polysaccharides in selected samples were further studied using ammonia CI(+) DT-MS. Principal component analysis of the resulting NH3-CI(+) spectra indicated that the majority of polysaccharide variation in the selected samples could be explained by a component related to the degree of degradation of the organic matter. The results from this thesis, coupled with existing work on marine organic matter, were used to support a modified "size-reactivity continuum model" of organic matter cycling.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1998
- Accession Number
- ADA351064
Entities
People
- Elizabeth C. Minor
Organizations
- Massachusetts Institute of Technology