Record Details

Foraminiferal assemblages preserved in surface sediments correspond to multiple environmental and preservation variables

ScholarsArchive at Oregon State University

Field Value
Title Foraminiferal assemblages preserved in surface sediments correspond to multiple environmental and preservation variables
Names Ross, Ann E. Morey (creator)
Mix, Alan C. (advisor)
Date Issued 2003-02-10 (iso8601)
Note Graduation date: 2003
Abstract Here we investigate the relationships between modern foraminiferal assemblages from Atlantic and Pacific surface sediment samples and multiple environmental properties including water column and preservation variables using Canonical Correspondence Analysis (CCA). CCA finds two fauna] dimensions that are highly correlated to the environmental variables included in the analysis, and then selects the best linear combination of environmental variables to explain sample positions along these dimensions. The first dimension (30.4% of the faunal variance) is related primarily to mean annual sea-surface temperature (SST, r = -0.955). Salinity, or some property correlated to it, also influences CCA Axis 1 within the tropics. The second dimension (7.9% of the faunal variance) accounts for environmental variability associated with an inverse relationship between SST and surface salinity, including variability in pycnocline phosphate concentration, range in nitrate concentration, water depth and chlorophyll. No evidence is found for a significant influence of selective dissolution, suggesting that carbonate ion concentration cannot be estimated for foraminiferal assemblages Our results support the use of foraminiferal assemblages preserved in deep-sea sediments to estimate SST. We use our results to develop a CCA-based transfer function using the relationship between SST and CCA Axis 1. We tested this new estimation method by reconstructing modern and LGM SSTs, and the SSTs down an eastern tropical Pacific sediment core, RC13-110.
Genre Thesis/Dissertation
Topic Foraminifera -- Ecology
Identifier http://hdl.handle.net/1957/22835

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