@article{CaronDeFrenneBrunetetal.2014,
  author    = {Caron, Maria Mercedes and De Frenne, P. and Brunet, J. and Chabrerie, Olivier and Cousins, S. A. O. and De Backer, L. and Diekmann, M. and Graae, B. J. and Heinken, Thilo and Kolb, A. and Naaf, T. and Plue, J. and Selvi, F. and Strimbeck, G. R. and Wulf, Monika and Verheyen, Kris},
  title     = {Latitudinal variation in seeds characteristics of Acer platanoides and A. pseudoplatanus},
  series = {Plant ecology : an international journal},
  volume    = {215},
  journal   = {Plant ecology : an international journal},
  number    = {8},
  publisher = {Springer},
  address   = {Dordrecht},
  issn      = {1385-0237},
  doi       = {10.1007/s11258-014-0343-x},
  pages     = {911 -- 925},
  year      = {2014},
  abstract  = {Climate change will likely affect population dynamics of numerous plant species by modifying several aspects of the life cycle. Because plant regeneration from seeds may be particularly vulnerable, here we assess the possible effects of climate change on seed characteristics and present an integrated analysis of seven seed traits (nutrient concentrations, samara mass, seed mass, wing length, seed viability, germination percentage, and seedling biomass) of Acer platanoides and A. pseudoplatanus seeds collected along a wide latitudinal gradient from Italy to Norway. Seed traits were analyzed in relation to the environmental conditions experienced by the mother trees along the latitudinal gradient. We found that seed traits of A. platanoides were more influenced by the climatic conditions than those of A. pseudoplatanus. Additionally, seed viability, germination percentage, and seedling biomass of A. platanoides were strongly related to the seed mass and nutrient concentration. While A. platanoides seeds were more influenced by the environmental conditions (generally negatively affected by rising temperatures), compared to A. pseudoplatanus, A. platanoides still showed higher germination percentage and seedling biomass than A. pseudoplatanus. Thus, further research on subsequent life-history stages of both species is needed. The variation in seed quality observed along the climatic gradient highlights the importance of studying the possible impact of climate change on seed production and species demography.},
  language  = {en}
}
@article{ReineckeWulfBaetenetal.2016,
  author    = {Reinecke, J. and Wulf, M. and Baeten, Lander and Brunet, J. and Decocq, G. and De Frenne, G. and Diekmann, M. and Graae, B. J. and Heinken, Thilo and Hermy, M. and Jamoneau, A. and Lenoir, J. and Plue, J. and Orczewska, A. and Van Calster, H. and Verheyen, Kris and Naaf, T.},
  title     = {Acido- and neutrophilic temperate forest plants display distinct shifts in ecological pH niche across north-western Europe},
  series = {Ecography : pattern and diversity in ecology ; research papers forum},
  volume    = {39},
  journal   = {Ecography : pattern and diversity in ecology ; research papers forum},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {0906-7590},
  doi       = {10.1111/ecog.02051},
  pages     = {1164 -- 1175},
  year      = {2016},
  abstract  = {Ecological niches of organisms vary across geographical space, but niche shift patterns between regions and the underlying mechanisms remain largely unexplored. We studied shifts in the pH niche of 42 temperate forest plant species across a latitudinal gradient from northern France to boreo-nemoral Sweden. We asked 1) whether species restrict their niches with increasing latitude as they reach their northern range margin (environmental constraints); 2) whether species expand their niches with increasing latitude as regional plant species richness decreases (competitive release); and 3) whether species shift their niche position toward more acidic sites with increasing latitude as the relative proportion of acidic soils increases (local adaptation). Based on 1458 vegetation plots and corresponding soil pH values, we modelled species response curves using Huisman-Olff-Fresco models. Four niche measures (width, position, left and right border) were compared among regions by randomization tests. We found that with increasing latitude, neutrophilic species tended to retreat from acidic sites, indicating that these species retreat to more favorable sites when approaching their range margin. Alternatively, these species might benefit from enhanced nitrogen deposition on formerly nutrient-poor, acidic sites in southern regions or lag behind in post-glacial recolonization of potential habitats in northern regions. Most acidophilic species extended their niche toward more base-rich sites with increasing latitude, indicating competitive release from neutrophilic species. Alternatively, acidophilic species might benefit from optimal climatic conditions in the north where some have their core distribution area. Shifts in the niche position suggested that local adaptation is of minor importance. We conclude that shifts in the pH niche of temperate forest plants are the rule, but the directions of the niche shifts and possible explanations vary. Our study demonstrates that differentiating between acidophilic and neutrophilic species is crucial to identify general patterns and underlying mechanisms.},
  language  = {en}
}
@article{DeFrenneBlondeelBrunetetal.2018,
  author    = {De Frenne, Pieter and Blondeel, H. and Brunet, J. and Caron, M. M. and Chabrerie, O. and Cougnon, M. and Cousins, S. A. O. and Decocq, G. and Diekmann, M. and Graae, B. J. and Hanley, M. E. and Heinken, Thilo and Hermy, M. and Kolb, A. and Lenoir, J. and Liira, J. and Orczewska, A. and Shevtsova, A. and Vanneste, T. and Verheyen, K.},
  title     = {Atmospheric nitrogen deposition on petals enhances seed quality of the forest herb Anemone nemorosa},
  series = {Plant biology},
  volume    = {20},
  journal   = {Plant biology},
  number    = {3},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {1435-8603},
  doi       = {10.1111/plb.12688},
  pages     = {619 -- 626},
  year      = {2018},
  abstract  = {Elevated atmospheric input of nitrogen (N) is currently affecting plant biodiversity and ecosystem functioning. The growth and survival of numerous plant species is known to respond strongly to N fertilisation. Yet, few studies have assessed the effects of N deposition on seed quality and reproductive performance, which is an important life-history stage of plants. Here we address this knowledge gap by assessing the effects of atmospheric N deposition on seed quality of the ancient forest herb Anemone nemorosa using two complementary approaches. By taking advantage of the wide spatiotemporal variation in N deposition rates in pan-European temperate and boreal forests over 2years, we detected positive effects of N deposition on the N concentration (percentage N per unit seed mass, increased from 2.8\% to 4.1\%) and N content (total N mass per seed more than doubled) of A.nemorosa seeds. In a complementary experiment, we applied ammonium nitrate to aboveground plant tissues and the soil surface to determine whether dissolved N sources in precipitation could be incorporated into seeds. Although the addition of N to leaves and the soil surface had no effect, a concentrated N solution applied to petals during anthesis resulted in increased seed mass, seed N concentration and N content. Our results demonstrate that N deposition on the petals enhances bioaccumulation of N in the seeds of A.nemorosa. Enhanced atmospheric inputs of N can thus not only affect growth and population dynamics via root or canopy uptake, but can also influence seed quality and reproduction via intake through the inflorescences.},
  language  = {en}
}