caa a22 4500 60551769X CHVBK 20210128100721.0 cr unu---uuuuu 210128e20150901xx s 000 0 eng 10.1007/s10533-015-0133-0 doi (NATIONALLICENCE)springer-10.1007/s10533-015-0133-0 Proximate controls on semiarid soil greenhouse gas fluxes across 3million years of soil development [Elektronische Daten] [Benjamin Sullivan, Megan Nasto, Stephen Hart, Bruce Hungate] Soils are important sources and sinks of three greenhouse gases (GHGs): carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). However, it is unknown whether semiarid landscapes are important contributors to global fluxes of these gases, partly because our mechanistic understanding of soil GHG fluxes is largely derived from more humid ecosystems. We designed this study with the objective of identifying the important soil physical and biogeochemical controls on soil GHG fluxes in semiarid soils by observing seasonal changes in soil GHG fluxes across a three million year substrate age gradient in northern Arizona. We also manipulated soil nitrogen (N) and phosphorus availability with 7years of fertilization and used regression tree analysis to identify drivers of unfertilized and fertilized soil GHG fluxes. Similar to humid ecosystems, soil N2O flux was correlated with changes in N and water availability and soil CO2 efflux was correlated with changes in water availability and temperature. Soil CH4 uptake was greatest in relatively colder and wetter soils. While fertilization had few direct effects on soil CH4 flux, soil nitrate was an important predictor of soil CH4 uptake in unfertilized soils and soil ammonium was an important predictor of soil CH4 uptake in fertilized soil. Like in humid ecosystems, N gas loss via nitrification or denitrification appears to increase with increases in N and water availability during ecosystem development. Our results suggest that, with some exceptions, the drivers of soil GHG fluxes in semiarid ecosystems are often similar to those observed in more humid ecosystems. Springer International Publishing Switzerland, 2015 Carbon dioxide nationallicence Methane nationallicence Nitrous oxide nationallicence Nutrient addition nationallicence Seasonality nationallicence Substrate age gradient nationallicence Sullivan Benjamin Department of Natural Resources and Environmental Science, University of Nevada-Reno, 1664N Virginia Street, Mail Stop 186, 89557, Reno, NV, USA aut Nasto Megan College of Forestry and Conservation, University of Montana, 32 Campus Drive, 59812, Missoula, MT, USA aut Hart Stephen Life and Environmental Sciences and Sierra Nevada Research Institute, University of California, Merced, 5200N. Lake Road, 95343, Merced, CA, USA aut Hungate Bruce Department of Biological Sciences and Center for Ecosystem Science and Society, Northern Arizona University, 86011, Flagstaff, AZ, USA aut Biogeochemistry Springer International Publishing 125/3(2015-09-01), 375-391 0168-2563 125:3<375 2015 125 10533 https://doi.org/10.1007/s10533-015-0133-0 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10533-015-0133-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Sullivan Benjamin Department of Natural Resources and Environmental Science, University of Nevada-Reno, 1664N Virginia Street, Mail Stop 186, 89557, Reno, NV, USA aut NATIONALLICENCE 700 1- Nasto Megan College of Forestry and Conservation, University of Montana, 32 Campus Drive, 59812, Missoula, MT, USA aut NATIONALLICENCE 700 1- Hart Stephen Life and Environmental Sciences and Sierra Nevada Research Institute, University of California, Merced, 5200N. Lake Road, 95343, Merced, CA, USA aut NATIONALLICENCE 700 1- Hungate Bruce Department of Biological Sciences and Center for Ecosystem Science and Society, Northern Arizona University, 86011, Flagstaff, AZ, USA aut NATIONALLICENCE 773 0- Biogeochemistry Springer International Publishing 125/3(2015-09-01), 375-391 0168-2563 125:3<375 2015 125 10533