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  - 
TY  - JOUR
A1  - Kurze, Susanne
A1  - Heinken, Thilo
A1  - Fartmann, Thomas
T1  - Nitrogen enrichment in host plants increases the mortality of common Lepidoptera species
JF  - Oecologia
N2  - The recent decline of Lepidoptera species strongly correlates with the increasing intensification of agriculture in Western and Central Europe. However, the effects of changed host-plant quality through agricultural fertilization on this insect group remain largely unexplored. For this reason, we tested the response of six common butterfly and moth species to host-plant fertilization using fertilizer quantities usually applied in agriculture. The larvae of the study species Coenonympha pamphilus, Lycaena phlaeas, Lycaena tityrus, Pararge aegeria, Rivula sericealis and Timandra comae were distributed according to a split-brood design to three host-plant treatments comprising one control treatment without fertilization and two fertilization treatments with an input of 150 and 300kgNha(-1)year(-1), respectively. In L.tityrus, we used two additional fertilization treatments with an input of 30 and 90kgNha(-1)year(-1), respectively. Fertilization increased the nitrogen concentration of both host-plant species, Rumex acetosella and Poa pratensis, and decreased the survival of larvae in all six Lepidoptera species by at least one-third, without clear differences between sorrel- and grass-feeding species. The declining survival rate in all species contradicts the well-accepted nitrogen-limitation hypothesis, which predicts a positive response in species performance to dietary nitrogen content. In contrast, this study presents the first evidence that current fertilization quantities in agriculture exceed the physiological tolerance of common Lepidoptera species. Our results suggest that (1) the negative effect of plant fertilization on Lepidoptera has previously been underestimated and (2) that it contributes to the range-wide decline of Lepidoptera.
KW  - Agricultural fertilization
KW  - Global change
KW  - Host-plant quality
KW  - Nitrogen-limitation hypothesis
KW  - Rearing experiment
Y1  - 2018
U6  - https://doi.org/10.1007/s00442-018-4266-4
SN  - 0029-8549
SN  - 1432-1939
VL  - 188
IS  - 4
SP  - 1227
EP  - 1237
PB  - Springer
CY  - New York
ER  -