@article{PlueDeFrenneAcharyaetal.2017, author = {Plue, Jan and De Frenne, Pieter and Acharya, Kamal and Brunet, J{\"o}rg and Chabrerie, Olivier and Decocq, Guillaume and Diekmann, Martin and Graae, Bente J. and Heinken, Thilo and Hermy, Martin and Kolb, Annette and Lemke, Isgard and Liira, Jaan and Naaf, Tobias and Verheyen, Kris and Wulf, Monika and Cousins, Sara A. O.}, title = {Where does the community start, and where does it end?}, series = {Journal of vegetation science}, volume = {28}, journal = {Journal of vegetation science}, number = {2}, publisher = {Wiley}, address = {Hoboken}, issn = {1100-9233}, doi = {10.1111/jvs.12493}, pages = {424 -- 435}, year = {2017}, abstract = {QuestionBelow-ground processes are key determinants of above-ground plant population and community dynamics. Still, our understanding of how environmental drivers shape plant communities is mostly based on above-ground diversity patterns, bypassing below-ground plant diversity stored in seed banks. As seed banks may shape above-ground plant communities, we question whether concurrently analysing the above- and below-ground species assemblages may potentially enhance our understanding of community responses to environmental variation. LocationTemperate deciduous forests along a 2000km latitudinal gradient in NW Europe. MethodsHerb layer, seed bank and local environmental data including soil pH, canopy cover, forest cover continuity and time since last canopy disturbance were collected in 129 temperate deciduous forest plots. We quantified herb layer and seed bank diversity per plot and evaluated how environmental variation structured community diversity in the herb layer, seed bank and the combined herb layer-seed bank community. ResultsSeed banks consistently held more plant species than the herb layer. How local plot diversity was partitioned across the herb layer and seed bank was mediated by environmental variation in drivers serving as proxies of light availability. The herb layer and seed bank contained an ever smaller and ever larger share of local diversity, respectively, as both canopy cover and time since last canopy disturbance decreased. Species richness and -diversity of the combined herb layer-seed bank community responded distinctly differently compared to the separate assemblages in response to environmental variation in, e.g. forest cover continuity and canopy cover. ConclusionsThe seed bank is a below-ground diversity reservoir of the herbaceous forest community, which interacts with the herb layer, although constrained by environmental variation in e.g. light availability. The herb layer and seed bank co-exist as a single community by means of the so-called storage effect, resulting in distinct responses to environmental variation not necessarily recorded in the individual herb layer or seed bank assemblages. Thus, concurrently analysing above- and below-ground diversity will improve our ecological understanding of how understorey plant communities respond to environmental variation.}, language = {en} } @article{NaafWulf2011, author = {Naaf, Tobias and Wulf, Monika}, title = {Traits of winner and loser species indicate drivers of herb layer changes over two decades in forests of NW Germany}, series = {Journal of vegetation science}, volume = {22}, journal = {Journal of vegetation science}, number = {3}, publisher = {Wiley-Blackwell}, address = {Malden}, issn = {1100-9233}, doi = {10.1111/j.1654-1103.2011.01267.x}, pages = {516 -- 527}, year = {2011}, abstract = {Questions What are the most likely environmental drivers for compositional herb layer changes as indicated by trait differences between winner and loser species? Location Weser-Elbe region (NW Germany). Methods We resurveyed the herb layer communities of ancient forest patches on base-rich sites of 175 semi-permanent plots. Species traits were tested for their ability to discriminate between winner and loser species using logistic regression analyses and deviance partitioning. Results Of 115 species tested, 31 were identified as winner species and 30 as loser species. Winner species had higher seed longevity, flowered later in the season and more often had an oceanic distribution compared to loser species. Loser species tended to have a higher specific leaf area, were more susceptible to deer browsing and had a performance optimum at higher soil pH compared to winner species. The loser species also represented several ancient forest and threatened species. Deviance partitioning indicated that local drivers (i.e. disturbance due to forest management) were primarily responsible for the species shifts, while regional drivers (i.e. browsing pressure and acidification from atmospheric deposition) and global drivers (i.e. climate warming) had moderate effects. There was no evidence that canopy closure, drainage or eutrophication contributed to herb layer changes. Conclusions The relative importance of the different drivers as indicated by the winner and loser species differs from that found in previous long-term studies. Relating species traits to species performance is a valuable tool that provides insight into the environmental drivers that are most likely responsible for herb layer changes.}, language = {en} } @article{HeimHoelzelHeinkenetal.2019, author = {Heim, Ramona J. and H{\"o}lzel, Norbert and Heinken, Thilo and Kamp, Johannes and Thomas, Alexander and Darman, Galina F. and Smirenski, Sergei M. and Heim, Wieland}, title = {Post-burn and long-term fire effects on plants and birds in floodplain wetlands of the Russian Far East}, series = {Biodiversity and conservation}, volume = {28}, journal = {Biodiversity and conservation}, number = {6}, publisher = {Springer}, address = {Dordrecht}, issn = {0960-3115}, doi = {10.1007/s10531-019-01746-3}, pages = {1611 -- 1628}, year = {2019}, abstract = {Wildfires affect biodiversity at multiple levels. While vegetation is directly changed by fire events, animals are often indirectly affected through changes in habitat and food availability. Globally, fire frequency and the extent of fires are predicted to increase in the future. The impact of fire on the biodiversity of temperate wetlands has gained little attention so far. We compared species richness and abundance of plants and birds in burnt and unburnt areas in the Amur floodplain/Russian Far East in the year of fire and 1 year after. We also analysed vegetation recovery in relation to time since fire over a period of 18 years. Plant species richness was higher in burnt compared to unburnt plots in the year of the fire, but not in the year after. This suggests that fire has a positive short-term effect on plant diversity. Bird species richness and abundance were lower on burnt compared to unburnt plots in the year of the fire, but not in the year after. Over a period of 18 years, high fire frequency led to an increase in herb cover and a decrease in grass cover. We show that the effects on biodiversity are taxon- and species-specific. Fire management strategies in temperate wetlands should consider fire frequency as a key driving force of vegetation structure, with carry-over effects on higher trophic levels. Designing fire refuges, i.e., areas that do not burn annually, might locally be necessary to maintain high species richness.}, language = {en} } @article{StarkBachGuill2021, author = {Stark, Markus and Bach, Moritz and Guill, Christian}, title = {Patch isolation and periodic environmental disturbances have idiosyncratic effects on local and regional population variabilities in meta-food chains}, series = {Theoretical ecology}, volume = {14}, journal = {Theoretical ecology}, number = {3}, publisher = {Springer}, address = {Dordrecht}, issn = {1874-1738}, doi = {10.1007/s12080-021-00510-0}, pages = {489 -- 500}, year = {2021}, abstract = {While habitat loss is a known key driver of biodiversity decline, the impact of other landscape properties, such as patch isolation, is far less clear. When patch isolation is low, species may benefit from a broader range of foraging opportunities, but are at the same time adversely affected by higher predation pressure from mobile predators. Although previous approaches have successfully linked such effects to biodiversity, their impact on local and metapopulation dynamics has largely been ignored. Since population dynamics may also be affected by environmental disturbances that temporally change the degree of patch isolation, such as periodic changes in habitat availability, accurate assessment of its link with isolation is highly challenging. To analyze the effect of patch isolation on the population dynamics on different spatial scales, we simulate a three-species meta-food chain on complex networks of habitat patches and assess the average variability of local populations and metapopulations, as well as the level of synchronization among patches. To evaluate the impact of periodic environmental disturbances, we contrast simulations of static landscapes with simulations of dynamic landscapes in which 30 percent of the patches periodically become unavailable as habitat. We find that increasing mean patch isolation often leads to more asynchronous population dynamics, depending on the parameterization of the food chain. However, local population variability also increases due to indirect effects of increased dispersal mortality at high mean patch isolation, consequently destabilizing metapopulation dynamics and increasing extinction risk. In dynamic landscapes, periodic changes of patch availability on a timescale much slower than ecological interactions often fully synchronize the dynamics. Further, these changes not only increase the variability of local populations and metapopulations, but also mostly overrule the effects of mean patch isolation. This may explain the often small and inconclusive impact of mean patch isolation in natural ecosystems.}, language = {en} } @article{BochPratiMuelleretal.2013, author = {Boch, Steffen and Prati, Daniel and M{\"u}ller, J{\"o}rg and Socher, Stephanie and Baumbach, Henryk and Buscot, Francois and Gockel, Sonja and Hemp, Andreas and Hessenm{\"o}ller, Dominik and Kalko, Elisabeth K. V. and Linsenmair, K. Eduard and Pfeiffer, Simone and Pommer, Ulf and Sch{\"o}ning, Ingo and Schulze, Ernst-Detlef and Seilwinder, Claudia and Weisser, Wolfgang W. and Wells, Konstans and Fischer, Markus}, title = {High plant species richness indicates management-related disturbances rather than the conservation status of forests}, series = {Basic and applied ecology : Journal of the Gesellschaft f{\"u}r {\"O}kologie}, volume = {14}, journal = {Basic and applied ecology : Journal of the Gesellschaft f{\"u}r {\"O}kologie}, number = {6}, publisher = {Elsevier}, address = {Jena}, issn = {1439-1791}, doi = {10.1016/j.baae.2013.06.001}, pages = {496 -- 505}, year = {2013}, abstract = {There is a wealth of smaller-scale studies on the effects of forest management on plant diversity. However, studies comparing plant species diversity in forests with different management types and intensity, extending over different regions and forest stages, and including detailed information on site conditions are missing. We studied vascular plants on 1500 20 m x 20 m forest plots in three regions of Germany (Schwabische Alb, Hainich-Dun, Schorfheide-Chorin). In all regions, our study plots comprised different management types (unmanaged, selection cutting, deciduous and coniferous age-class forests, which resulted from clear cutting or shelterwood logging), various stand ages, site conditions, and levels of management-related disturbances. We analyzed how overall richness and richness of different plant functional groups (trees, shrubs, herbs, herbaceous species typically growing in forests and herbaceous light-demanding species) responded to the different management types. On average, plant species richness was 13\% higher in age-class than in unmanaged forests, and did not differ between deciduous age-class and selection forests. In age-class forests of the Schwabische Alb and Hainich-Dun, coniferous stands had higher species richness than deciduous stands. Among age-class forests, older stands with large quantities of standing biomass were slightly poorer in shrub and light-demanding herb species than younger stands. Among deciduous forests, the richness of herbaceous forest species was generally lower in unmanaged than in managed forests, and it was even 20\% lower in unmanaged than in selection forests in Hainich-Dun. Overall, these findings show that disturbances by management generally increase plant species richness. This suggests that total plant species richness is not suited as an indicator for the conservation status of forests, but rather indicates disturbances.}, language = {en} }