@misc{WagnerPywellKnoppetal.2011,
  author    = {Wagner, Markus and Pywell, Richard F. and Knopp, Tatjana and Bullock, James M. and Heard, Matthew S.},
  title     = {The germination niches of grassland species targeted for restoration},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe},
  number    = {675},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-41343},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-413438},
  pages     = {117 -- 131},
  year      = {2011},
  abstract  = {Restoration of semi-natural grassland communities involves a combination of (1) sward disturbance to create a temporal window for establishment, and (2) target species introduction, the latter usually by seed sowing. With great regularity, particular species establish only poorly. More reliable establishment could improve outcome of restoration projects and increase cost-effectiveness. We investigated the abiotic germination niche of ten poorly establishing calcareous grassland species by simultaneously exploring the effects of moisture and light availability and temperature fluctuation on percentage germina- tion and speed of germination. We also investigated the effects of three different pre-treatments used to enhance seed germination - cold-stratification, osmo- tic priming and priming in combination with gibberellic acid (GA 3 ) - and how these affected abiotic germination niches. Species varied markedly in width of abiotic germination niche, ranging from Carex flacca with very strict abiotic requirements, to several species reliably germinating across the whole range of abiotic conditions. Our results suggest pronounced differ- ences between species in gap requirements for establishment. Germination was improved in most species by at least one pre-treatment. Evidence for positive effects of adding GA 3 to seed priming solutions was limited. In several species, pre-treated seeds germinated under a wider range of abiotic conditions than untreated seeds. Improved knowledge of species-specific germination niches and the effects of seed pre-treatments may help to improve species establishment by sowing, and to identify species for which sowing at a later stage of restoration or introduction as small plants may represent a more viable strategy.},
  language  = {en}
}
@article{DiekmannAndresBeckeretal.2019,
  author    = {Diekmann, Martin and Andres, Christian and Becker, Thomas and Bennie, Jonathan and Blueml, Volker and Bullock, James M. and Culmsee, Heike and Fanigliulo, Miriam and Hahn, Annett and Heinken, Thilo and Leuschner, Christoph and Luka, Stefanie and Meissner, Justus and M{\"u}ller, Josef and Newton, Adrian and Peppler-Lisbach, Cord and Rosenthal, Gert and van den Berg, Leon J. L. and Vergeer, Philippine and Wesche, Karsten},
  title     = {Patterns of long-term vegetation change vary between different types of semi-natural grasslands in Western and Central Europe},
  series = {Journal of vegetation science},
  volume    = {30},
  journal   = {Journal of vegetation science},
  number    = {2},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {1100-9233},
  doi       = {10.1111/jvs.12727},
  pages     = {187 -- 202},
  year      = {2019},
  abstract  = {Questions Has plant species richness in semi-natural grasslands changed over recent decades? Do the temporal trends of habitat specialists differ from those of habitat generalists? Has there been a homogenization of the grassland vegetation? Location Different regions in Germany and the UK. Methods We conducted a formal meta-analysis of re-survey vegetation studies of semi-natural grasslands. In total, 23 data sets were compiled, spanning up to 75 years between the surveys, including 13 data sets from wet grasslands, six from dry grasslands and four from other grassland types. Edaphic conditions were assessed using mean Ellenberg indicator values for soil moisture, nitrogen and pH. Changes in species richness and environmental variables were evaluated using response ratios. Results In most wet grasslands, total species richness declined over time, while habitat specialists almost completely vanished. The number of species losses increased with increasing time between the surveys and were associated with a strong decrease in soil moisture and higher soil nutrient contents. Wet grasslands in nature reserves showed no such changes or even opposite trends. In dry grasslands and other grassland types, total species richness did not consistently change, but the number or proportions of habitat specialists declined. There were also considerable changes in species composition, especially in wet grasslands that often have been converted into intensively managed, highly productive meadows or pastures. We did not find a general homogenization of the vegetation in any of the grassland types. Conclusions The results document the widespread deterioration of semi-natural grasslands, especially of those types that can easily be transformed to high production grasslands. The main causes for the loss of grassland specialists are changed management in combination with increased fertilization and nitrogen deposition. Dry grasslands are most resistant to change, but also show a long-term trend towards an increase in more mesotrophic species.},
  language  = {en}
}
@article{vonderLippeBullockKowariketal.2013,
  author    = {von der Lippe, Moritz and Bullock, James M. and Kowarik, Ingo and Knopp, Tatjana and Wichmann, Matthias},
  title     = {Human-mediated dispersal of seeds by the airflow of vehicles},
  series = {PLoS one},
  volume    = {8},
  journal   = {PLoS one},
  number    = {1},
  publisher = {PLoS},
  address   = {San Fransisco},
  issn      = {1932-6203},
  doi       = {10.1371/journal.pone.0052733},
  pages     = {10},
  year      = {2013},
  abstract  = {Human-mediated dispersal is known as an important driver of long-distance dispersal for plants but underlying mechanisms have rarely been assessed. Road corridors function as routes of secondary dispersal for many plant species but the extent to which vehicles support this process remains unclear. In this paper we quantify dispersal distances and seed deposition of plant species moved over the ground by the slipstream of passing cars. We exposed marked seeds of four species on a section of road and drove a car along the road at a speed of 48 km/h. By tracking seeds we quantified movement parallel as well as lateral to the road, resulting dispersal kernels, and the effect of repeated vehicle passes. Median distances travelled by seeds along the road were about eight meters for species with wind dispersal morphologies and one meter for species without such adaptations. Airflow created by the car lifted seeds and resulted in longitudinal dispersal. Single seeds reached our maximum measuring distance of 45 m and for some species exceeded distances under primary dispersal. Mathematical models were fit to dispersal kernels. The incremental effect of passing vehicles on longitudinal dispersal decreased with increasing number of passes as seeds accumulated at road verges. We conclude that dispersal by vehicle airflow facilitates seed movement along roads and accumulation of seeds in roadside habitats. Dispersal by vehicle airflow can aid the spread of plant species and thus has wide implications for roadside ecology, invasion biology and nature conservation.},
  language  = {en}
}