Volcanogenic nutrient fluxes and plant ecosystems in large igneous provinces: an example from the Columbia River Basalt Group
DAVID W. JOLLEY
MIKE WIDDOWSON
STEPHEN SELF
10.6084/m9.figshare.3454532.v1
https://geolsoc.figshare.com/articles/dataset/Volcanogenic_nutrient_fluxes_and_plant_ecosystems_in_large_igneous_provinces_an_example_from_the_Columbia_River_Basalt_Group/3454532
<p>Research from biological and geological sources has highlighted the role of volcanoes in the outgassing of P, and thermal
fixation and subsequent atmospheric oxidation of NO<em><sub>x</sub></em> in volcanic environments. The impact of these nutrient fluxes on biological systems has been demonstrated on present-day
Hawai'i, and here we consider the impact on the plant communities within a large igneous province (LIP). The Miocene Columbia
River Basalt Province, the youngest LIP on Earth, contains many sedimentary interbeds between the flows of the major extrusive
phase, and these interbeds preserve variable but often diverse palynofloras. By integration of palynofloral analysis with
analysis of macronutrient levels in the interbeds it can be suggested that there may have been significantly elevated levels
of P within the lava field proximal to the source vents, a distribution mirrored by Ca and Mg. Evidence for potential volcanogenic
eutrophication is restricted to >10<sup>3</sup> year duration interbeds, contemporary with eruptive activity elsewhere in the LIP. The geochemistry and palynology of other
interbeds demonstrate nutrient deficiency, with a potential route to nutrient sufficiency available from long-term symbiotic
N-fixation. Elsewhere within the Columbia River Basalt Province, this process is short-circuited by the imput of felsic ash
from the nearby Cascades Range of volcanoes.
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2016-06-21 12:11:19
macronutrient levels
Miocene Columbia River Basalt Province
eruptive activity
source vents
impact
interbed
Cascades Range
Columbia River Basalt Group Research
palynofloral analysis
plant ecosystems
province
extrusive phase
Columbia River Basalt Province
plant communities
felsic ash
flux
lava field
volcanogenic eutrophication
Geology