caa a22 4500 605517037 CHVBK 20210128100717.0 cr unu---uuuuu 210128e20150401xx s 000 0 eng 10.1007/s10533-015-0073-8 doi (NATIONALLICENCE)springer-10.1007/s10533-015-0073-8 Soil warming and nitrogen deposition alter soil organic matter composition at the molecular-level [Elektronische Daten] [Oliva Pisani, Serita Frey, André Simpson, Myrna Simpson] Rising temperatures and nitrogen (N) deposition, both aspects of global environmental change, are proposed to alter soil organic matter (SOM) biogeochemistry. For example, increased plant productivity and enhanced microbial decomposition of litter and SOM may reduce soil carbon stocks and fertility. To better understand SOM biogeochemical shifts at the molecular-level, we employed an array of biomarker and nuclear magnetic resonance (NMR) techniques to investigate the composition and degradation of SOM components in the forest floor and mineral soil horizons of warmed (5°C above average soil temperature) and N fertilized (5gm−2year−1 N applied in the growing season) plots from the soil warming×nitrogen addition study at the Harvard Forest, MA, USA. Biomarker analyses indicated increased plant-derived inputs into the forest floor under N fertilization. Soil warming promoted the decomposition of plant-derived aliphatic and cyclic compounds in the forest floor. Cutin degradation was observed in the heated forest floor which also exhibited relatively higher microbial activity. Lignin oxidation was also observed but was most pronounced in the mineral horizon of the heated plots. These results suggest that continued soil warming may promote the degradation of lignin- and cuticle-derived SOM. N fertilization also enhanced lignin oxidation but to a lesser extent likely due to a decline in microbial activity. 1H NMR spectra of the mineral soils revealed enrichment of plant-derived alkyl structures and microbial-derived organic matter with both soil warming and N fertilization. Overall, this study shows that the decomposition and accumulation of molecularly distinct SOM components occurs with soil warming and N amendment and may subsequently alter soil biogeochemical cycling. Springer International Publishing Switzerland, 2015 Lignin nationallicence Cutin nationallicence Suberin nationallicence Soil organic matter turnover nationallicence Biomarkers nationallicence Nuclear magnetic resonance nationallicence Pisani Oliva Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail, M1C 1A4, Toronto, ON, Canada aut Frey Serita Department of Natural Resources and the Environment, University of New Hampshire, 03824, Durham, NH, USA aut Simpson André Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail, M1C 1A4, Toronto, ON, Canada aut Simpson Myrna Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail, M1C 1A4, Toronto, ON, Canada aut Biogeochemistry Springer International Publishing 123/3(2015-04-01), 391-409 0168-2563 123:3<391 2015 123 10533 https://doi.org/10.1007/s10533-015-0073-8 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/s10533-015-0073-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Pisani Oliva Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail, M1C 1A4, Toronto, ON, Canada aut NATIONALLICENCE 700 1- Frey Serita Department of Natural Resources and the Environment, University of New Hampshire, 03824, Durham, NH, USA aut NATIONALLICENCE 700 1- Simpson André Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail, M1C 1A4, Toronto, ON, Canada aut NATIONALLICENCE 700 1- Simpson Myrna Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail, M1C 1A4, Toronto, ON, Canada aut NATIONALLICENCE 773 0- Biogeochemistry Springer International Publishing 123/3(2015-04-01), 391-409 0168-2563 123:3<391 2015 123 10533