Premium
First interactions with the hydrologic cycle determine pyrogenic carbon's fate in the Earth system
Author(s) -
Masiello Caroline Ann,
Berhe Asmeret Asefaw
Publication year - 2020
Publication title -
earth surface processes and landforms
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.294
H-Index - 127
eISSN - 1096-9837
pISSN - 0197-9337
DOI - 10.1002/esp.4925
Subject(s) - landform , sedimentary depositional environment , earth science , environmental science , carbon cycle , particulates , persistence (discontinuity) , geology , ecology , geomorphology , ecosystem , geotechnical engineering , structural basin , biology
Fires produce an aromatic particulate residue commonly referred to as pyrogenic carbon (PyC). Particulate PyC is low density, high porosity, and is predominantly deposited on the soil surface in post‐fire landscapes. These characteristics create a material that is prone to mobility, both vertically down the soil profile and laterally across the landscape even in low‐relief landforms. Because of its tendency for lateral mobilization, we argue here that PyC's first interaction with water determines its environmental fate and persistence, not its interactions with soil minerals or microbes. PyC's first interactions with water determine: the amount of PyC that will enter the soil profile and experience microbial and geochemical alterations, whether it will be buried in depositional environments and stored on the landscape, or if it will be transported to streams and eventually to the ocean. Here we posit that this crucial first interaction with the hydrologic cycle occurs on the timescale of days to weeks, and therefore supersedes microbial decomposition as the primary control on PyC's environmental persistence. © 2020 John Wiley & Sons, Ltd.