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N2O and CH4 fluxes in undisturbed and burned holm oak, scots pine and pyrenean oak forests in central Spain

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An Erratum to this article was published on 28 May 2013

Abstract

We investigated N2O and CH4 fluxes from soils of Quercus ilex, Quercus pyrenaica and Pinus sylvestris stands located in the surrounding area of Madrid (Spain). The fluxes were measured for 18 months from both mature stands and post fire stands using the static chamber technique. Simultaneously with gas fluxes, soil temperature, soil water content, soil C and soil N were measured in the stands. Nitrous oxide fluxes ranged from −11.43 to 8.34 μg N2O–N m−2 h−1 in Q.ilex, −7.74 to 13.52 μg N2O–N m−2 h−1 in Q. pyrenaica and −28.17 to 21.89 μg N2O–N m−2 h−1 in P. sylvestris. Fluxes of CH4 ranged from −8.12 to 4.11 μg CH4–C m−2 h−1 in Q.ilex, −7.74 to 3.0 μg CH4–C m−2 h−1 in Q. pyrenaica and −24.46 to 6.07 μg CH4–C m−2 h−1 in P. sylvestris. Seasonal differences were detected; N2O fluxes being higher in wet months whereas N2O fluxes declined in dry months. Net consumption of N2O was related to low N availability, high soil C contents, high soil temperatures and low moisture content. Fire decreased N2O fluxes in spring. N2O emissions were closely correlated with previous day’s rainfall and soil moisture. Our ecosystems generally were a sink for methane in the dry season and a source of CH4 during wet months. The available water in the soil influenced the observed seasonal trend. The burned sites showed higher CH4 oxidation rates in Q. ilex, and lower rates in P. sylvestris. Overall, the data suggest that fire alters both N2O and CH4 fluxes. However, the magnitude of such variation depends on the site, soil characteristics and seasonal climatic conditions.

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Acknowledgments

This research was conducted in the framework of the Spanish CGL2006-02922/CLI and CGL2009-07031 and the European COST 639 (BurnOut). The authors want to express their gratitude to Stoyan Holding LTD., Patrimonio Nacional and Community of Madrid for the employment of their forest sites.

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  1. Departamento de Medio Ambiente, CIEMAT, Avda. Complutense 22, 28040, Madrid, Spain

    Rosa Inclán, Carla Uribe, Dolores M. Sánchez, Ángeles Clavero, Ana María Fernández & Ramón Morante

  2. Department of Agricultural Chemistry, Polytechnic University of Madrid, Ciudad Universitaria, s/n, 28040, Madrid, Spain

    Laura Sánchez

  3. Department of Silvopascicultura, Polytechnic University of Madrid, Ciudad Universitaria, s/n, 28040, Madrid, Spain

    Alfredo Blanco

  4. Federal Office and Research Centre for Forests, 1131, Vienna, Austria

    Robert Jandl

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  1. Rosa Inclán
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An erratum to this article is available at http://dx.doi.org/10.1007/s10533-013-9866-9.

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Inclán, R., Uribe, C., Sánchez, L. et al. N2O and CH4 fluxes in undisturbed and burned holm oak, scots pine and pyrenean oak forests in central Spain. Biogeochemistry 107, 19–41 (2012). https://doi.org/10.1007/s10533-010-9520-8

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