Greenhouse gas fluxes over managed grasslands in Central Europe

Medientyp: E-Artikel
Titel: Greenhouse gas fluxes over managed grasslands in Central Europe
Beteiligte: Hörtnagl, Lukas; Barthel, Matti; Buchmann, Nina; Eugster, Werner; Butterbach‐Bahl, Klaus; Díaz‐Pinés, Eugenio; Zeeman, Matthias; Klumpp, Katja; Kiese, Ralf; Bahn, Michael; Hammerle, Albin; Lu, Haiyan; Ladreiter‐Knauss, Thomas; Burri, Susanne; Merbold, Lutz
Erschienen: Wiley, 2018
Erschienen in: Global Change Biology
Sprache: Englisch
DOI: 10.1111/gcb.14079
ISSN: 1354-1013; 1365-2486
Entstehung:
Anmerkungen:
Beschreibung: <jats:title>Abstract</jats:title><jats:p>Central European grasslands are characterized by a wide range of different management practices in close geographical proximity. Site‐specific management strategies strongly affect the biosphere–atmosphere exchange of the three greenhouse gases (<jats:styled-content style="fixed-case">GHG</jats:styled-content>) carbon dioxide (<jats:styled-content style="fixed-case">CO</jats:styled-content><jats:sub>2</jats:sub>), nitrous oxide (N<jats:sub>2</jats:sub>O), and methane (<jats:styled-content style="fixed-case">CH</jats:styled-content><jats:sub>4</jats:sub>). The evaluation of environmental impacts at site level is challenging, because most in situ measurements focus on the quantification of <jats:styled-content style="fixed-case">CO</jats:styled-content><jats:sub>2</jats:sub> exchange, while long‐term N<jats:sub>2</jats:sub>O and <jats:styled-content style="fixed-case">CH</jats:styled-content><jats:sub>4</jats:sub> flux measurements at ecosystem scale remain scarce. Here, we synthesized ecosystem <jats:styled-content style="fixed-case">CO</jats:styled-content><jats:sub>2</jats:sub>, N<jats:sub>2</jats:sub>O, and <jats:styled-content style="fixed-case">CH</jats:styled-content><jats:sub>4</jats:sub> fluxes from 14 managed grassland sites, quantified by eddy covariance or chamber techniques. We found that grasslands were on average a <jats:styled-content style="fixed-case">CO</jats:styled-content><jats:sub>2</jats:sub> sink (−1,783 to −91 g <jats:styled-content style="fixed-case">CO</jats:styled-content><jats:sub>2</jats:sub> m<jats:sup>−2</jats:sup> year<jats:sup>−1</jats:sup>), but a N<jats:sub>2</jats:sub>O source (18–638 g <jats:styled-content style="fixed-case">CO</jats:styled-content><jats:sub>2</jats:sub>‐eq. m<jats:sup>−2</jats:sup> year<jats:sup>−1</jats:sup>), and either a <jats:styled-content style="fixed-case">CH</jats:styled-content><jats:sub>4</jats:sub> sink or source (−9 to 488 g <jats:styled-content style="fixed-case">CO</jats:styled-content><jats:sub>2</jats:sub>‐eq. m<jats:sup>−2</jats:sup> year<jats:sup>−1</jats:sup>). The net <jats:styled-content style="fixed-case">GHG</jats:styled-content> balance (<jats:styled-content style="fixed-case">NGB</jats:styled-content>) of nine sites where measurements of all three <jats:styled-content style="fixed-case">GHG</jats:styled-content>s were available was found between −2,761 and −58 g <jats:styled-content style="fixed-case">CO</jats:styled-content><jats:sub>2</jats:sub>‐eq. m<jats:sup>−2</jats:sup> year<jats:sup>−1</jats:sup>, with N<jats:sub>2</jats:sub>O and <jats:styled-content style="fixed-case">CH</jats:styled-content><jats:sub>4</jats:sub> emissions offsetting concurrent <jats:styled-content style="fixed-case">CO</jats:styled-content><jats:sub>2</jats:sub> uptake by on average 21 ± 6% across sites. The only positive <jats:styled-content style="fixed-case">NGB</jats:styled-content> was found for one site during a restoration year with ploughing. The predictive power of soil parameters for N<jats:sub>2</jats:sub>O and <jats:styled-content style="fixed-case">CH</jats:styled-content><jats:sub>4</jats:sub> fluxes was generally low and varied considerably within years. However, after site‐specific data normalization, we identified environmental conditions that indicated enhanced <jats:styled-content style="fixed-case">GHG</jats:styled-content> source/sink activity (“sweet spots”) and gave a good prediction of normalized overall fluxes across sites. The application of animal slurry to grasslands increased N<jats:sub>2</jats:sub>O and <jats:styled-content style="fixed-case">CH</jats:styled-content><jats:sub>4</jats:sub> emissions. The N<jats:sub>2</jats:sub>O‐N emission factor across sites was 1.8 ± 0.5%, but varied considerably at site level among the years (0.1%–8.6%). Although grassland management led to increased N<jats:sub>2</jats:sub>O and <jats:styled-content style="fixed-case">CH</jats:styled-content><jats:sub>4</jats:sub> emissions, the <jats:styled-content style="fixed-case">CO</jats:styled-content><jats:sub>2</jats:sub> sink strength was generally the most dominant component of the annual <jats:styled-content style="fixed-case">GHG</jats:styled-content> budget.</jats:p>

Nur in Feld suchen:

Zuletzt gesuchte Begriffe: