Incubation of ombrotrophic bog litter and mixtures of Sphagnum, Betula and Calluna results in the formation of single litter-specific decomposition patterns

Autor(en)

Raphael Müller, Apoline Zahorka, Franz Holawe, Erich Inselsbacher, Stephan Glatzel

Abstrakt

Peat accumulation is the result of an imbalance between the biomass production and the reduced decomposition of organic matter, which has allowed peatlands to accumulate high levels of carbon over time. Sphagnum-dominated peatlands are among the most threatened ecosystems due to increasing anthropogenic pressures and harsher environmental conditions caused by climate change. The resulting changes in vegetation alter litter interactions and change decomposition patterns by altering nutrient cycling, hydrological conditions and carbon sequestration capacity of bogs. The aim of this study was to identify decomposition patterns for different bog litter types and mixtures over time. We sampled litter from an ombrotrophic bog (Sphagnum, Betula, Calluna), prepared mixtures of litter types and incubated our samples under laboratory conditions. We evaluated decomposition proxies and used k-means clustering to detect the formation of litter- and mixture-specific decomposition patterns over time. Sphagnum litter had a consistently low decomposition and its presence in mixtures reduced enzymatic activities. Initially, Betula litter added high amounts of N and labile C compounds to leachates. k-means clustering revealed a typical initial decomposition pattern (i.e. lowest decomposition directly after starting the incubation, followed by highest decomposition rates, and a steady decrease until the end) for most litter types, except for Sphagnum. Litter-specific decomposition patterns emerged after 14 days. Betula litter did not enhance decomposition of other litter types in our short-term incubation, but additional nutrient inputs could alter peat-litter interactions in the long term, increasing the risk of losing the carbon sink function of nutrient-poor bogs.

Organisation(en)

Institut für Geographie und Regionalforschung

Externe Organisation(en)

Universität für Bodenkultur Wien, École Normale Supérieure, Paris

Journal

Geoderma

Band

440

ISSN

0016-7061

DOI

https://doi.org/10.1016/j.geoderma.2023.116702

Publikationsdatum

12-2023

Peer-reviewed

Ja

ÖFOS 2012

105205 Klimawandel, 106058 Bodenbiologie, 105405 Geoökologie

Schlagwörter

ASJC Scopus Sachgebiete

Soil Science

Sustainable Development Goals

SDG 13 – Maßnahmen zum Klimaschutz

Link zum Portal

https://ucris.univie.ac.at/portal/de/publications/incubation-of-ombrotrophic-bog-litter-and-mixtures-of-sphagnum-betula-and-calluna-results-in-the-formation-of-single-litterspecific-decomposition-patterns(6d92fb1d-0424-411b-9d2d-8d6a9b3339bc).html