Abstract:
:Wildfire can influence climate directly and indirectly, but little is known about the relationships between wildfire and climate during the Quaternary, especially how wildfire patterns varied over glacial-interglacial cycles. Here, we present a high-resolution soot record from the Chinese Loess Plateau; this is a record of large-scale, high-intensity fires over the past 2.6 My. We observed a unique and distinct glacial-interglacial cyclicity of soot over the entire Quaternary Period synchronous with marine δ18O and dust records, which suggests that ice-volume-modulated aridity controlled wildfire occurrences, soot production, and dust fluxes in central Asia. The high-intensity fires were also found to be anticorrelated with global atmospheric CO2 records over the past eight glacial-interglacial cycles, implying a possible connection between the fires, dust, and climate mediated through the iron cycle. The significance of this hypothetical connection remains to be determined, but the relationships revealed in this study hint at the potential importance of wildfire for the global climate system.
journal_name
Proc Natl Acad Sci U S Aauthors
Han Y,An Z,Marlon JR,Bradley RS,Zhan C,Arimoto R,Sun Y,Zhou W,Wu F,Wang Q,Burr GS,Cao Jdoi
10.1073/pnas.1822035117subject
Has Abstractpub_date
2020-03-10 00:00:00pages
5184-5189issue
10eissn
0027-8424issn
1091-6490pii
1822035117journal_volume
117pub_type
杂志文章abstract::A mitochondrial gene from Saccharomyces cerevisiae encoding a hydrophobic membrane protein, subunit 8 of the F0/F1-type mitochondrial ATPase complex, has been functionally replaced by an artificial nuclear gene specifying an imported version of this protein. The experiments reported here utilized a multicopy expressio...
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