TY - JOUR
T1 - Climate change disrupts the seasonal coupling of plant and soil microbial nutrient cycling in an alpine ecosystem
AU - Broadbent, Arthur A.D.
AU - Newbold, Lindsay K.
AU - Pritchard, William J.
AU - Michas, Antonios
AU - Goodall, Tim
AU - Cordero, Irene
AU - Giunta, Andrew
AU - Snell, Helen S.K.
AU - Pepper, Violette V.L.H.
AU - Grant, Helen K.
AU - Soto, David X.
AU - Kaufmann, Ruediger
AU - Schloter, Michael
AU - Griffiths, Robert I.
AU - Bahn, Michael
AU - Bardgett, Richard D.
N1 - Publisher Copyright:
© 2024 The Authors. Global Change Biology published by John Wiley & Sons Ltd.
PY - 2024/3
Y1 - 2024/3
N2 - The seasonal coupling of plant and soil microbial nutrient demands is crucial for efficient ecosystem nutrient cycling and plant production, especially in strongly seasonal alpine ecosystems. Yet, how these seasonal nutrient cycling processes are modified by climate change and what the consequences are for nutrient loss and retention in alpine ecosystems remain unclear. Here, we explored how two pervasive climate change factors, reduced snow cover and shrub expansion, interactively modify the seasonal coupling of plant and soil microbial nitrogen (N) cycling in alpine grasslands, which are warming at double the rate of the global average. We found that the combination of reduced snow cover and shrub expansion disrupted the seasonal coupling of plant and soil N-cycling, with pronounced effects in spring (shortly after snow melt) and autumn (at the onset of plant senescence). In combination, both climate change factors decreased plant organic N-uptake by 70% and 82%, soil microbial biomass N by 19% and 38% and increased soil denitrifier abundances by 253% and 136% in spring and autumn, respectively. Shrub expansion also individually modified the seasonality of soil microbial community composition and stoichiometry towards more N-limited conditions and slower nutrient cycling in spring and autumn. In winter, snow removal markedly reduced the fungal:bacterial biomass ratio, soil N pools and shifted bacterial community composition. Taken together, our findings suggest that interactions between climate change factors can disrupt the temporal coupling of plant and soil microbial N-cycling processes in alpine grasslands. This could diminish the capacity of these globally widespread alpine ecosystems to retain N and support plant productivity under future climate change.
AB - The seasonal coupling of plant and soil microbial nutrient demands is crucial for efficient ecosystem nutrient cycling and plant production, especially in strongly seasonal alpine ecosystems. Yet, how these seasonal nutrient cycling processes are modified by climate change and what the consequences are for nutrient loss and retention in alpine ecosystems remain unclear. Here, we explored how two pervasive climate change factors, reduced snow cover and shrub expansion, interactively modify the seasonal coupling of plant and soil microbial nitrogen (N) cycling in alpine grasslands, which are warming at double the rate of the global average. We found that the combination of reduced snow cover and shrub expansion disrupted the seasonal coupling of plant and soil N-cycling, with pronounced effects in spring (shortly after snow melt) and autumn (at the onset of plant senescence). In combination, both climate change factors decreased plant organic N-uptake by 70% and 82%, soil microbial biomass N by 19% and 38% and increased soil denitrifier abundances by 253% and 136% in spring and autumn, respectively. Shrub expansion also individually modified the seasonality of soil microbial community composition and stoichiometry towards more N-limited conditions and slower nutrient cycling in spring and autumn. In winter, snow removal markedly reduced the fungal:bacterial biomass ratio, soil N pools and shifted bacterial community composition. Taken together, our findings suggest that interactions between climate change factors can disrupt the temporal coupling of plant and soil microbial N-cycling processes in alpine grasslands. This could diminish the capacity of these globally widespread alpine ecosystems to retain N and support plant productivity under future climate change.
KW - alpine ecosystems
KW - climate change
KW - nutrient cycling
KW - plant–soil interactions
KW - seasonality
KW - shrub expansion
KW - snow cover
UR - http://www.scopus.com/inward/record.url?scp=85188499836&partnerID=8YFLogxK
U2 - 10.1111/gcb.17245
DO - 10.1111/gcb.17245
M3 - Article
C2 - 38511487
AN - SCOPUS:85188499836
SN - 1354-1013
VL - 30
JO - Global Change Biology
JF - Global Change Biology
IS - 3
M1 - e17245
ER -