Temperature sensitivity of soil respiration declines with climate warming in subalpine and alpine grassland soils

Title data

Abdalla, Khatab ; Schierling, Larissa ; Sun, Yue ; Schuchardt, Max A. ; Jentsch, Anke ; Deola, Thomas ; Wolff, Peter ; Kiese, Ralf ; Lehndorff, Eva ; Pausch, Johanna ; Meyer, Nele:
Temperature sensitivity of soil respiration declines with climate warming in subalpine and alpine grassland soils.
In: Biogeochemistry. (9 October 2024) .
ISSN 1573-515X
DOI: https://doi.org/10.1007/s10533-024-01179-3

Official URL:

Abstract in another language

Warming as a climate change phenomenon affects soil organic matter dynamics, especially in high elevation ecosystems. However, our understanding of the controls of soil organic matter mineralization and dynamics remains limited, particularly in alpine (above treeline) and subalpine (below treeline) grassland ecosystems. Here, we investigated how downslope (warming) and upslope (cooling) translocations, in a 5-years reciprocal transplanting experiment, affects soil respiration and its temperature sensitivity (Q10), soil aggregation, and soil organic matter carbon (C) and nitrogen (N) composition (C/N ratio). Downslope translocation of the alpine (2440 m a.s.l.) and subalpine (1850 m a.s.l.) to the lowland site (350 m a.s.l.) resulted in a temperature change during the growing seasons of + 4.4K and + 3.3K, respectively. Warming of alpine soils (+ 4.4K) reduced soil organic carbon (SOC) content by 32%, which was accompanied by a significant decrease of soil macroaggregates. Macroaggregate breakdown induced an increased respiration quotient (qCO2) by 27% following warming of alpine soils. The increase in qCO2 respiration was associated with a significant decrease (from 2.84 ± 0.05 to 2.46 ± 0.05) in Q10, and a change in soil organic matter composition (lower C/N ratios). Cooling did not show the opposite patterns to warming, implying that other mechanisms, such as plant and microbial community shifts and adaptation, were involved. This study highlights the important role of SOC degradability in regulating the temperature response of soil organic matter mineralization. To predict the adverse effect of warming on soil CO2 release and, consequently, its negative feedback on climate change, a comprehensive understanding of the mechanisms of C storage and turnover is needed, especially at high elevations in the Alps that are particularly affected by rising temperatures.

Further data

Item Type:	Article in a journal
Refereed:	Yes
Keywords:	Grasslands; Soil aggregates; Soil organic matter; Climate change
Institutions of the University:	Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Earth Sciences > Professor Agroecology > Professor Agroecology - Juniorprof. Dr. Johanna Pausch Faculties Faculties > Faculty of Biology, Chemistry and Earth Sciences Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Earth Sciences Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Earth Sciences > Professor Agroecology
Result of work at the UBT:	Yes
DDC Subjects:	500 Science > 500 Natural sciences 500 Science > 570 Life sciences, biology
Date Deposited:	19 Oct 2024 21:00
Last Modified:	21 Oct 2024 09:49
URI:	https://eref.uni-bayreuth.de/id/eprint/90773