Using the natural spatial pattern of marine productivity in the Subarctic North Pacific to evaluate paleoproductivity proxies
OPEN ACCESS
Loading...
Author / Producer
Date
2014-05
Publication Type
Journal Article
ETH Bibliography
yes
OPEN ACCESS
Data
Rights / License
Abstract
Sedimentary proxies used to reconstruct marine productivity suffer from variable preservation and are sensitive to factors other than productivity. Therefore, proxy calibration is warranted. Here we map the spatial patterns of two paleoproductivity proxies, biogenic opal and barium fluxes, from a set of core-top sediments recovered in the Subarctic North Pacific. Comparisons of the proxy data with independent estimates of primary and export production, surface water macronutrient concentrations, and biological pCO₂ drawdown indicate that neither proxy shows a significant correlation with primary or export productivity for the entire region. Biogenic opal fluxes, when corrected for preservation using ²³⁰Th-normalized accumulation rates, show a good correlation with primary productivity along the volcanic arcs (τ = 0.71, p = 0.0024) and with export productivity throughout the western Subarctic North Pacific (τ = 0.71, p = 0.0107). Moderate and good correlations of biogenic barium flux with export production (τ = 0.57, p = 0.0022) and with surface water silicate concentrations (τ = 0.70, p = 0.0002) are observed for the central and eastern Subarctic North Pacific. For reasons unknown, however, no correlation is found in the western Subarctic North Pacific between biogenic barium flux and the reference data. Nonetheless, we show that barite saturation, uncertainty in the lithogenic barium corrections, and problems with the reference data sets are not responsible for the lack of a significant correlation between biogenic barium flux and the reference data. Further studies evaluating the factors controlling the variability of the biogenic constituents in the sediments are desirable in this region.
Permanent link
Publication status
published
External links
Editor
Book title
Journal / series
Volume
29 (5)
Pages / Article No.
438 - 453
Publisher
American Geophysical Union
Event
Edition / version
Methods
Software
Geographic location
Date collected
Date created
Subject
Marine productivity; Paleoproductivity; Subarctic North Pacific; INOPEX; Biogenic opal; Biogenic barium
Organisational unit
03775 - Haug, Gerald H. / Haug, Gerald H.