@article{HeinzeWernerWeberetal.2015,
  author    = {Heinze, Johannes and Werner, Tony and Weber, Ewald and Rillig, Matthias C. and Joshi, Jasmin Radha},
  title     = {Soil biota effects on local abundances of three grass species along a land-use gradient},
  series = {Oecologia},
  volume    = {179},
  journal   = {Oecologia},
  number    = {1},
  publisher = {Springer},
  address   = {New York},
  issn      = {0029-8549},
  doi       = {10.1007/s00442-015-3336-0},
  pages     = {249 -- 259},
  year      = {2015},
  abstract  = {Biotic plant-soil interactions and land-use intensity are known to affect plant individual fitness as well as competitiveness and therefore plant-species abundances in communities. Therefore, a link between soil biota and land-use intensity on local abundance of plant species in grasslands can be expected. In two greenhouse experiments, we investigated the effects of soil biota from grassland sites differing in land-use intensity on three grass species that vary in local abundances along this land-use gradient. We were interested in those soil-biota effects that are associated with land-use intensity, and whether these effects act directly or indirectly. Therefore, we grew the three plant species in two separate experiments as single individuals and in mixtures and compared their performance. As single plants, all three grasses showed a similar performance with and without soil biota. In contrast, in mixtures growth of the species in response to the presence or absence of soil biota differed. This resulted in different soil-biota effects that tend to correspond with patterns of species-specific abundances in the field for two of the three species tested. Our results highlight the importance of indirect interactions between plants and soil microorganisms and suggest that combined effects of soil biota and plant-plant interactions are involved in structuring plant communities. In conclusion, our experiments suggest that soil biota may have the potential to alter effects of plant-plant interactions and therefore influence plant-species abundances and diversity in grasslands.},
  language  = {en}
}
@article{HeinzeJoshi2017,
  author    = {Heinze, Johannes and Joshi, Jasmin Radha},
  title     = {Plant-soil feedback effects can be masked by aboveground herbivory under natural field conditions},
  series = {Oecologia},
  volume    = {186},
  journal   = {Oecologia},
  number    = {1},
  publisher = {Springer},
  address   = {New York},
  issn      = {0029-8549},
  doi       = {10.1007/s00442-017-3997-y},
  pages     = {235 -- 246},
  year      = {2017},
  abstract  = {For plants, herbivory and interactions with their surrounding soil ecosystem are crucial factors influencing individual performance and plant-community composition. Until now, research has mostly focused on individual effects of herbivory or plant-soil feedbacks (PSFs) on plant growth and community composition, but few studies have explicitly investigated herbivory in the context of PSFs. These few studies, however, were performed under greenhouse conditions even though PSFs and herbivory may differ between greenhouse and field conditions. Therefore, we performed a field experiment in a grassland, testing the growth responses of three grass species that consistently differ in local abundance, on soils previously conditioned by these species. We tested these PSF effects for the three species both in the presence and in the absence of aboveground herbivores. Without herbivores, the two subdominant species suffered from negative PSF effects. However, in the presence of herbivores and on heterospecific soils, the same two species experienced a significant loss of shoot biomass, whereas, in contrast, enhanced root growth was observed on conspecific soils, resulting in overall neutral PSF effects. The dominant species was not damaged by herbivores and showed overall neutral PSF effects in the field with and without herbivores. Our study provides empirical evidence that negative PSF effects that exist under natural field conditions in grasslands can be overwhelmed by aboveground herbivory. Hence, potential PSF effects might not be detected in the field, because other abiotic and biotic interactions such as aboveground herbivory have stronger effects on plant performance and might therefore mask or override these PSF effects.},
  language  = {en}
}
@article{HeinzeSimonsSeiboldetal.2019,
  author    = {Heinze, Johannes and Simons, Nadja K. and Seibold, Sebastian and Wacker, Alexander and Weithoff, Guntram and Gossner, Martin M. and Prati, Daniel and Bezemer, T. Martijn and Joshi, Jasmin Radha},
  title     = {The relative importance of plant-soil feedbacks for plant-species performance increases with decreasing intensity of herbivory},
  series = {Oecologia},
  volume    = {190},
  journal   = {Oecologia},
  number    = {3},
  publisher = {Springer},
  address   = {New York},
  issn      = {0029-8549},
  doi       = {10.1007/s00442-019-04442-9},
  pages     = {651 -- 664},
  year      = {2019},
  abstract  = {Under natural conditions, aboveground herbivory and plant-soil feedbacks (PSFs) are omnipresent interactions strongly affecting individual plant performance. While recent research revealed that aboveground insect herbivory generally impacts the outcome of PSFs, no study tested to what extent the intensity of herbivory affects the outcome. This, however, is essential to estimate the contribution of PSFs to plant performance under natural conditions in the field. Here, we tested PSF effects both with and without exposure to aboveground herbivory for four common grass species in nine grasslands that formed a gradient of aboveground invertebrate herbivory. Without aboveground herbivores, PSFs for each of the four grass species were similar in each of the nine grasslands-both in direction and in magnitude. In the presence of herbivores, however, the PSFs differed from those measured under herbivory exclusion, and depended on the intensity of herbivory. At low levels of herbivory, PSFs were similar in the presence and absence of herbivores, but differed at high herbivory levels. While PSFs without herbivores remained similar along the gradient of herbivory intensity, increasing herbivory intensity mostly resulted in neutral PSFs in the presence of herbivores. This suggests that the relative importance of PSFs for plant-species performance in grassland communities decreases with increasing intensity of herbivory. Hence, PSFs might be more important for plant performance in ecosystems with low herbivore pressure than in ecosystems with large impacts of insect herbivores.},
  language  = {en}
}