TY - JOUR A1 - Müller, Jörg A1 - Heinze, Johannes A1 - Joshi, Jasmin Radha A1 - Boch, Steffen A1 - Klaus, Valentin H. A1 - Fischer, Markus A1 - Prati, Daniel T1 - Influence of experimental soil disturbances on the diversity of plants in agricultural grasslands JF - Journal of plant ecology N2 - Disturbance is supposed to play an important role for biodiversity and ecosystem stability as described by the intermediate disturbance hypothesis (IDH), which predicts highest species richness at intermediate levels of disturbances. In this study, we tested the effects of artificial soil disturbances on diversity of annual and perennial vascular plants and bryophytes in a field experiment in 86 agricultural grasslands differing in land use in two regions of Germany. On each grassland, we implemented four treatments: three treatments differing in application time of soil disturbances and one control. One year after experimental disturbance, we recorded vegetation and measured biomass productivity and bare ground. We analysed the disturbance response taking effects of region and land-use-accompanied disturbance regimes into account. Region and land-use type strongly determined plant species richness. Experimental disturbances had small positive effects on the species richness of annuals, but none on perennials or bryophytes. Bare ground was positively related to species richness of bryophytes. However, exceeding the creation of 12% bare ground further disturbance had a detrimental effect on bryophyte species richness, which corresponds to the IDH. As biomass productivity was unaffected by disturbance our results indicate that the disturbance effect on species richness of annuals was not due to decreased overall productivity, but rather due to short-term lowered inter- and intraspecific competition at the newly created microsites. Generally, our results highlight the importance of soil disturbances for species richness of annual plants and bryophytes in agricultural grasslands. However, most grasslands were disturbed naturally or by land-use practices and our additional experimental soil disturbances only had a small short-term effect. Overall, total plant diversity in grasslands seemed to be more limited by the availability of propagules rather than by suitable microsites for germination. Thus, nature conservation efforts to increase grassland diversity should focus on overcoming propagule limitation, for instance by additional sowing of seeds, while the creation of additional open patches by disturbance might only be appropriate where natural disturbances are scarce. KW - annuals KW - bryophytes KW - colonization KW - intermediate disturbance hypothesis KW - microsites Y1 - 2014 U6 - https://doi.org/10.1093/jpe/rtt062 SN - 1752-9921 SN - 1752-993X VL - 7 IS - 6 SP - 509 EP - 517 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Heinze, Johannes A1 - Werner, Tony A1 - Weber, Ewald A1 - Rillig, Matthias C. A1 - Joshi, Jasmin Radha T1 - Soil biota effects on local abundances of three grass species along a land-use gradient JF - Oecologia N2 - 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. KW - Biodiversity KW - Grassland KW - Land-use intensity KW - Community composition KW - Plant-soil feedback Y1 - 2015 U6 - https://doi.org/10.1007/s00442-015-3336-0 SN - 0029-8549 SN - 1432-1939 VL - 179 IS - 1 SP - 249 EP - 259 PB - Springer CY - New York ER - TY - JOUR A1 - Bergmann, Joana A1 - Verbruggen, Erik A1 - Heinze, Johannes A1 - Xiang, Dan A1 - Chen, Baodong A1 - Joshi, Jasmin Radha A1 - Rillig, Matthias C. T1 - The interplay between soil structure, roots, and microbiota as a determinant of plant-soil feedback JF - Ecology and evolution N2 - Plant-soil feedback (PSF) can influence plant community structure via changes in the soil microbiome. However, how these feedbacks depend on the soil environment remains poorly understood. We hypothesized that disintegrating a naturally aggregated soil may influence the outcome of PSF by affecting microbial communities. Furthermore, we expected plants to differentially interact with soil structure and the microbial communities due to varying root morphology. We carried out a feedback experiment with nine plant species (five forbs and four grasses) where the training phase consisted of aggregated versus disintegrated soil. In the feedback phase, a uniform soil was inoculated in a fully factorial design with soil washings from conspecific- versus heterospecific-trained soil that had been either disintegrated or aggregated. This way, the effects of prior soil structure on plant performance in terms of biomass production and allocation were examined. In the training phase, soil structure did not affect plant biomass. But on disintegrated soil, plants with lower specific root length (SRL) allocated more biomass aboveground. PSF in the feedback phase was negative overall. With training on disintegrated soil, conspecific feedback was positively correlated with SRL and significantly differed between grasses and forbs. Plants with higher SRL were likely able to easily explore the disintegrated soil with smaller pores, while plants with lower SRL invested in belowground biomass for soil exploration and seemed to be more susceptible to fungal pathogens. This suggests that plants with low SRL could be more limited by PSF on disintegrated soils of early successional stages. This study is the first to examine the influence of soil structure on PSF. Our results suggest that soil structure determines the outcome of PSF mediated by SRL. We recommend to further explore the effects of soil structure and propose to include root performance when working with PSF. KW - arbuscular mycorrhizal fungi KW - biomass allocation KW - plant functional traits KW - plant-soil (belowground) interactions KW - soil aggregation KW - specific root length KW - succession KW - water-stable aggregates Y1 - 2016 U6 - https://doi.org/10.1002/ece3.2456 SN - 2045-7758 VL - 6 SP - 7633 EP - 7644 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Heinze, Johannes A1 - Sitte, Mario A1 - Schindhelm, Anne A1 - Wright, J. A1 - Joshi, Jasmin Radha T1 - Plant-soil feedbacks: a comparative study on the relative importance of soil feedbacks in the greenhouse versus the field JF - Oecologia N2 - Interactions between plants and soil microorganisms influence individual plant performance and thus plant-community composition. Most studies on such plant-soil feedbacks (PSFs) have been performed under controlled greenhouse conditions, whereas no study has directly compared PSFs under greenhouse and natural field conditions. We grew three grass species that differ in local abundance in grassland communities simultaneously in the greenhouse and field on field-collected soils either previously conditioned by these species or by the general grassland community. As soils in grasslands are typically conditioned by mixes of species through the patchy and heterogeneous plant species’ distributions, we additionally compared the effects of species-specific versus non-specific species conditioning on PSFs in natural and greenhouse conditions. In almost all comparisons PSFs differed between the greenhouse and field. In the greenhouse, plant growth in species-specific and non-specific soils resulted in similar effects with neutral PSFs for the most abundant species and positive PSFs for the less abundant species. In contrast, in the field all grass species tested performed best in non-specific plots, whereas species-specific PSFs were neutral for the most abundant and varied for the less abundant species. This indicates a general beneficial effect of plant diversity on PSFs in the field. Controlled greenhouse conditions might provide valuable insights on the nominal effects of soils on plants. However, the PSFs observed in greenhouse conditions may not be the determining drivers in natural plant communities where their effects may be overwhelmed by the diversity of abiotic and biotic above- and belowground interactions in the field. KW - Grassland KW - Plant performance KW - Experimental environment KW - Community assembly KW - Plant diversity Y1 - 2016 U6 - https://doi.org/10.1007/s00442-016-3591-8 SN - 0029-8549 SN - 1432-1939 VL - 181 SP - 559 EP - 569 PB - Springer CY - New York ER - TY - JOUR A1 - Heinze, Johannes A1 - Bergmann, Joana A1 - Rillig, Matthias C. A1 - Joshi, Jasmin Radha T1 - Negative biotic soil-effects enhance biodiversity by restricting potentially dominant plant species in grasslands JF - Perspectives in plant ecology, evolution and systematics N2 - Interactions between soil microorganisms and plants can play a vital role for plant fitness and therefore also for plant community composition and biodiversity. However, little is known about how biotic plant soil interactions influence the local dominance and abundance of plant species and whether specific taxonomic or functional groups of plants are differentially affected by such biotic soil-effects. In two greenhouse experiments, we tested the biotic soil-effects of 33 grassland species differing in individual size and local abundance. We hypothesized that large plants that are not locally dominant (despite their size-related competitive advantage enabling them to potentially outshade competitors) are most strongly limited by negative biotic soil-effects. We sampled soils at the opposite ends of a gradient in land-use intensity in temperate grasslands to account for putative modulating effects of land-use intensity on biotic soil-effects. As hypothesized, large, but non-dominant species (especially grasses) experienced more negative biotic soil-effects compared with small and abundant plant species. Land-use intensity had contrasting effects on grasses and herbs resulting in more negative biotic soil-effects for grasses in less intensively managed grasslands. We conclude that biotic soil-effects contribute to the control of potentially dominant plants and hence enable species coexistence and biodiversity especially in species-rich less intensively managed grasslands. KW - Coexistence mechanisms KW - Plant soil feedbacks KW - Individual size KW - Local plant-abundance KW - Grassland diversity KW - Land-use intensity Y1 - 2015 U6 - https://doi.org/10.1016/j.ppees.2015.03.002 SN - 1433-8319 VL - 17 IS - 3 SP - 227 EP - 235 PB - Elsevier CY - Jena ER - TY - JOUR A1 - Heinze, Johannes A1 - Simons, Nadja K. A1 - Seibold, Sebastian A1 - Wacker, Alexander A1 - Weithoff, Guntram A1 - Gossner, Martin M. A1 - Prati, Daniel A1 - Bezemer, T. Martijn A1 - Joshi, Jasmin Radha T1 - The relative importance of plant-soil feedbacks for plant-species performance increases with decreasing intensity of herbivory JF - Oecologia N2 - 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. KW - Plant-soil feedback KW - Herbivorous insects KW - Field conditions KW - Selective herbivory KW - Nutritional quality Y1 - 2019 U6 - https://doi.org/10.1007/s00442-019-04442-9 SN - 0029-8549 SN - 1432-1939 VL - 190 IS - 3 SP - 651 EP - 664 PB - Springer CY - New York ER -