TY  - JOUR
A1  - De Lombaerde, Emiel
A1  - Verheyen, Kris
A1  - Perring, Michael P.
A1  - Bernhardt-Roemermann, Markus
A1  - Van Calster, Hans
A1  - Brunet, Jorg
A1  - Chudomelova, Marketa
A1  - Decocq, Guillaume
A1  - Diekmann, Martin
A1  - Durak, Tomasz
A1  - Hedl, Radim
A1  - Heinken, Thilo
A1  - Hommel, Patrick
A1  - Jaroszewicz, Bogdan
A1  - Kopecky, Martin
A1  - Lenoir, Jonathan
A1  - Macek, Martin
A1  - Máliš, František
A1  - Mitchell, Fraser J. G.
A1  - Naaf, Tobias
A1  - Newman, Miles
A1  - Petřík, Petr
A1  - Reczyńska, Kamila
A1  - Schmidt, Wolfgang
A1  - Swierkosz, Krzysztof
A1  - Vild, Ondrej
A1  - Wulf, Monika
A1  - Baetena, Lander
T1  - Responses of competitive understorey species to spatial environmental gradients inaccurately explain temporal changes
JF  - Basic and applied ecology : Journal of the Gesellschaft für Ökologie
N2  - Understorey plant communities play a key role in the functioning of forest ecosystems. Under favourable environmental conditions, competitive understorey species may develop high abundances and influence important ecosystem processes such as tree regeneration. Thus, understanding and predicting the response of competitive understorey species as a function of changing environmental conditions is important for forest managers. In the absence of sufficient temporal data to quantify actual vegetation changes, space-for-time (SFT) substitution is often used, i.e. studies that use environmental gradients across space to infer vegetation responses to environmental change over time. Here we assess the validity of such SFT approaches and analysed 36 resurvey studies from ancient forests with low levels of recent disturbances across temperate Europe to assess how six competitive understorey plant species respond to gradients of overstorey cover, soil conditions, atmospheric N deposition and climatic conditions over space and time. The combination of historical and contemporary surveys allows (i) to test if observed contemporary patterns across space are consistent at the time of the historical survey, and, crucially, (ii) to assess whether changes in abundance over time given recorded environmental change match expectations from patterns recorded along environmental gradients in space. We found consistent spatial relationships at the two periods: local variation in soil variables and overstorey cover were the best predictors of individual species’ cover while interregional variation in coarse-scale variables, i.e. N deposition and climate, was less important. However, we found that our SFT approach could not accurately explain the large variation in abundance changes over time. We thus recommend to be cautious when using SFT substitution to infer species responses to temporal changes.
KW  - Temperate forest
KW  - Herb layer
KW  - Tree regeneration
KW  - Global change
KW  - Nitrogen deposition
KW  - Canopy
KW  - Spatiotemporal resurvey data
KW  - Cover abundance
KW  - Chronosequence
KW  - forestREplot
Y1  - 2018
U6  - https://doi.org/10.1016/j.baae.2018.05.013
SN  - 1439-1791
SN  - 1618-0089
VL  - 30
SP  - 52
EP  - 64
PB  - Elsevier GMBH
CY  - München
ER  -