Autotrophic and heterotrophic organisms require resources in stoichiometrically balanced ratios of carbon (C) to nutrients, the demand for which links organismal and ecosystem-level biogeochemical cycles. In soils, the relative availability of C and nitrogen (N) also defines the strength of competition for ammonium between autotrophic nitrifiers and heterotrophic decomposers, which may influence the coupled dynamics between N mineralization and nitrification. Here, we use data from the publicly available US National Science Foundation funded Long Term Ecological Research (LTER) network to evaluate the influence of soil C concentration on the relationship between net nitrification and net N mineralization. We found that soil C availability constrains the fraction of mineralized N that is ultimately nitrified across the continental gradient, contributing to reduced rates of nitrification in soils with high C concentrations. Nitrate, which is produced by nitrification, is a highly mobile ion that easily leaches to aquatic ecosystems or denitrifies into the greenhouse gas nitrous oxide (N2O). Understanding the connection between soil C concentration and soil N transformations is thus important for managing potential ecosystem N losses, understanding the biogeochemical constraints of these losses, and accurately representing coupled C-N dynamics in ecosystem models.
|Original language||English (US)|
|Number of pages||12|
|State||Published - Jan 2023|
Bibliographical noteFunding Information:
This research was supported by a Grand Challenges in Biology Postdoctoral Fellowship from the University of Minnesota to ALG, Williams College Divisional Research Funds to ALG and RMG, and a NatureNet Science Fellowship to ADK. Initial discussions of the project were supported by workshop funding at the 2018 Long Term Ecological Research Network’s All Scientist Meeting. This material is based upon work supported by the National Science Foundation under grants to the Arctic LTER (DEB-1637459, DEB-1026843, DEB-981022, DEB-9211775, DEB-8702328; OPP-9911278, OPP-9911681, OPP-9732281, OPP- 9615411, OPP-9615563, OPP-9615942, OPP-9615949, OPP-9400722, OPP-9415411, OPP-9318529; BSR- BSR-9019055, BSR-8806635, BSR-8507493); the Baltimore Ecosystem Study (DEB-1637661 and DEB-1855277); the Bonanza Creek LTER and the USDA Forest Service, Pacific Northwest Research Station (DEB-1636476, RJVA-PNW-01-JV-11261952-231); the HJ Andrews Experimental Forest LTER, administered cooperatively by the USDA Forest Service Pacific Northwest Research Station, Oregon State University, and the Willamette National Forest (DEB-2025755 and DEB-1440409); the Cedar Creek Ecosystem Science Reserve and University of Minnesota (DEB-0620652, DEB-1234162, and DEB-1831944); the Central Arizona-Phoenix LTER and Arizona State University (DEB-1832016); the Coweeta LTER (DEB-1637522, DEB-1440485, DEB-0823293, DEB-9632854 and DEB-0218001); the Harvard Forest LTER (DEB-8811764, DEB-9411975, DEB-0080592, DEB-0620443, and DEB-1237491); the Hubbard Brook Ecosystem Study (DEB-8702331, DEB-9211768, DEB-9810221, DEB-0423259, DEB-1114804); the Jornada Basin LTER and New Mexico State University (DEB-2025126); the Kellogg Biological Station and the Michigan State University AgBioResearch (DEB-1832042); the Konza Prairie LTER (DEB-2025849) conducted at the Konza Prairie Biological Station; the Niwot Ridge LTER (DEB-1637686); and the Seviletta LTER and the University of New Mexico (DEB-881906, DEB-9411976, DEB-0080529, DEB-0217774, DEB-1232294, DEB-1440478, DEB-1655499).
© 2023, The Author(s), under exclusive licence to Springer Nature Switzerland AG.
- Long Term Ecological Research
- Nitrogen mineralization
- Soil carbon