Community structure of marine sedimentary protists in relation to flow and grain size
MetadataShow full item record
Populations of unicellular, marine sedimentary protists are constrained by a variety of physical environmental factors, but influences of flow regime have rarely been studied. We compared community structure among 3 subtidal sites differing in flow strength and grain size in a coastal bay. We used denaturing gradient gel electrophoresis (DGGE) to assess eukaryotic diversity based on 18S rDNA, and quantitative Protargol staining (QPS) to examine ciliate communities by microscopy. Sedimentary 18S rDNA in mid-summer was dominated by diatoms. Analyses of gel bands by presence/ absence among sites, dendogram, and multidimensional scaling showed that eukaryotic community structure was related to grain size more strongly than to flow regime. Among bands identified as diatoms by recovery and sequence analysis, 4 taxa (40%) differed among sites in relation to flow strength, and 2 taxa (29%) differed in relation to grain size. No bands had sequences matching ciliates, but QPS showed that 6 ciliate species (20%) were distributed in relation to flow, and 10 species (33%), in relation to grain size. Ciliate species richness and community similarity were greatest for the 2 strong-flow sites, despite differences in mean grain size. The strong-flow, silty site had the highest concentrations of chlorophyll a, total ciliates, karyorelictids, and scuticociliates, and the lowest ciliate species diversity. DGGE was run again for this site 1 mo later and revealed a shift in the rDNA pool to dominance by metazoans. Flow regime and grain size may be important factors structuring subtidal communities of sedimentary protists.
Author Posting. © Inter-Research, 2007. This article is posted here by permission of Inter-Research for personal use, not for redistribution. The definitive version was published in Aquatic Microbial Ecology 48 (2007): 91-104, doi:10.3354/ame048091.
Suggested CitationArticle: Shimeta, Jeff, Gast, Rebecca J., Rose, Julie M., "Community structure of marine sedimentary protists in relation to flow and grain size", Aquatic Microbial Ecology 48 (2007): 91-104, DOI:10.3354/ame048091, https://hdl.handle.net/1912/4522
Showing items related by title, author, creator and subject.
Influence of grain size evolution and water content on the seismic structure of the oceanic upper mantle Elsenbeck, James R. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2007-06)Grain size is an important material property that has significant effects on the viscosity, dominant deformation mechanism, attenuation, and shear wave velocity of the oceanic upper mantle. Several studies have investigated ...
Behn, Mark D.; Hirth, Greg; Elsenbeck, James R. (2009-03-04)We construct a 1-D steady-state channel flow model for grain size evolution in the oceanic upper mantle using a composite diffusion-dislocation creep rheology. Grain size evolution is calculated assuming that grain size ...
Ciliate diversity, community structure, and novel taxa in lakes of the McMurdo Dry Valleys, Antarctica Xu, Yuan; Vick-Majors, Trista; Morgan-Kiss, Rachael; Priscu, John C.; Amaral-Zettler, Linda A. (Marine Biological Laboratory, 2014-10-01)We report an in-depth survey of next-generation DNA sequencing of ciliate diversity and community structure in two permanently ice-covered McMurdo Dry Valley lakes during the austral summer and autumn (November 2007 and ...