Type

Journal Article

Authors

Guillermo Rein
Jennifer C McElwain
Rory M Hadden
Jonathan M Yearsley
Claire M Belcher

Subjects

Biochemistry

Topics
biological evolution oxygen earth planet time factors ecosystem fires air atmosphere metabolism

Baseline intrinsic flammability of Earth's ecosystems estimated from paleoatmospheric oxygen over the past 350 million years. (2010)

Abstract Atmospheric oxygen (O(2)) is estimated to have varied greatly throughout Earth's history and has been capable of influencing wildfire activity wherever fuel and ignition sources were present. Fires consume huge quantities of biomass in all ecosystems and play an important role in biogeochemical cycles. This means that understanding the influence of O(2) on past fire activity has far-reaching consequences for the evolution of life and Earth's biodiversity over geological timescales. We have used a strong electrical ignition source to ignite smoldering fires, and we measured their self-sustaining propagation in atmospheres of different oxygen concentrations. These data have been used to build a model that we use to estimate the baseline intrinsic flammability of Earth's ecosystems according to variations in O(2) over the past 350 million years (Ma). Our aim is to highlight times in Earth's history when fire has been capable of influencing the Earth system. We reveal that fire activity would be greatly suppressed below 18.5% O(2), entirely switched off below 16% O(2), and rapidly enhanced between 19-22% O(2). We show that fire activity and, therefore, its influence on the Earth system would have been high during the Carboniferous (350-300 Ma) and Cretaceous (145-65 Ma) periods; intermediate in the Permian (299-251 Ma), Late Triassic (285-201 Ma), and Jurassic (201-145 Ma) periods; and surprisingly low to lacking in the Early-Middle Triassic period between 250-240 Ma. These baseline variations in Earth's flammability must be factored into our understanding of past vegetation, biodiversity, evolution, and biogeochemical cycles.
Collections Ireland -> University College Dublin -> PubMed

Full list of authors on original publication

Guillermo Rein, Jennifer C McElwain, Rory M Hadden, Jonathan M Yearsley, Claire M Belcher

Experts in our system

1
Guillermo Rein
University College Dublin
 
2
Jennifer C McElwain
University College Dublin
Total Publications: 25
 
3
Rory M. Hadden
University College Dublin
 
4
Jonathan M Yearsley
University College Dublin
 
5
Claire M. Belcher
University College Dublin
Total Publications: 6