title: Fungal decomposition of terrestrial organic matter accelerated Early Jurassic climate warming.
abstract: Soils - constituting the largest terrestrial carbon pool - are vulnerable to climatic warming. Currently existing uncertainties regarding carbon fluxes within terrestrial systems can be addressed by studies of past carbon cycle dynamics and related climate change recorded in sedimentary successions. Here we show an example from the Early Jurassic (early Toarcian, c. 183 mya) marginal-marine strata from Poland, tracking the hinterland response to climatic changes through a super-greenhouse event. In contrast to anoxia-related enhanced carbon storage in coeval open marine environments, Total Organic Carbon (TOC) concentrations in the Polish successions are substantially reduced during this event. Increasing temperature favoured fungal-mediated decomposition of plant litter - specifically of normally resistant woody tissues. The associated injection of oxidized organic matter into the atmosphere corresponds to abrupt changes in standing vegetation and may have contributed significantly to the amplified greenhouse climate on Earth. The characteristic Toarcian signature of multiple warm pulses coinciding with rapidly decreasing carbon isotope ratios may in part be the result of a radical reduction of the terrestrial carbon pool as a response to climate change.
authors.affiliation: Polish Geological Institute - National Research Institute, Rakowiecka 4, PL-00-975 Warszawa, Poland.
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Pieńkowski
authors.affiliation: Polish Geological Institute - National Research Institute, Rakowiecka 4, PL-00-975 Warszawa, Poland.
authors.forename: Marta
authors.initials: M
authors.lastname: Hodbod
authors.affiliation: University of Exeter, Camborne School of Mines and Environment and Sustainability Institute, Penryn Campus, Penryn, Treliever Road, TE10 9FE, UK.
authors.forename: Clemens V
authors.initials: CV
authors.lastname: Ullmann
mesh_terms: D002244:Carbon / Q000378:metabolism*; D057486:Carbon Cycle; D002245:Carbon Dioxide / Q000378:metabolism; D002247:Carbon Isotopes / Q000737:chemistry; D057231:Climate Change; D018534:Earth, Planet; D017753:Ecosystem; D005658:Fungi / Q000378:metabolism*; D019015:Geologic Sediments / Q000737:chemistry / Q000382:microbiology; D017752:Greenhouse Effect; D013172:Spores, Fungal / Q000378:metabolism
chemical_list: D002247:Carbon Isotopes; D002245:Carbon Dioxide; D002244:Carbon