@article{GeisslerFiedlerNietal.2019,
  author    = {Geissler, Katja and Fiedler, Sebastian and Ni, Jian and Herzschuh, Ulrike and Jeltsch, Florian},
  title     = {Combined effects of grazing and climate warming drive shrub dominance on the Tibetan Plateau},
  series = {The Rangeland journal},
  volume    = {41},
  journal   = {The Rangeland journal},
  number    = {5},
  publisher = {CSIRO Publishing},
  address   = {Collingwood},
  issn      = {1036-9872},
  doi       = {10.1071/RJ19027},
  pages     = {425 -- 439},
  year      = {2019},
  abstract  = {Encroachment of shrubs into the unique pastoral grassland ecosystems of the Tibetan Plateau has significant impact on ecosystem services, especially forage production. We developed a process-based ecohydrological model to identify the relative importance of the main drivers of shrub encroachment for the alpine meadows within the Qinghai province. Specifically, we explored the effects of summer livestock grazing (intensity and type of livestock) together with the effects of climate warming, including interactions between herbaceous and woody vegetation and feedback loops between soil, water and vegetation. Under current climatic conditions and a traditional herd composition, an increasing grazing intensity above a threshold value of 0.32 +/- 0.10 large stock units (LSU) ha(-1) day(-1) changes the vegetation composition from herbaceous towards a woody and bare soil dominated system. Very high grazing intensity (above 0.8 LSU ha(-1) day(-1)) leads to a complete loss of any vegetation. Under warmer conditions, the vegetation showed a higher resilience against livestock farming. This resilience is enhanced when the herd has a higher browser : grazer ratio. A cooler climate has a shrub encroaching effect, whereas warmer conditions increase the cover of the herbaceous vegetation. This effect was primarily due to season length and an accompanied competitive loss of slower growing shrubs, rather than evaporative water loss leading to less soil water in deeper soil layers for deeper rooting shrubs. If climate warming is driving current shrub encroachment, we conclude it is only indirectly so. It would be manifest by an advancing shrubline and could be regarded as a climatic escape of specific shrub species such as Potentilla fruticosa. Under the recent high intensity of grazing, only herding by more browsing animals can potentially prevent both shrub encroachment and the complete loss of herbaceous vegetation.},
  language  = {en}
}
@article{WeissSchalowJeltschetal.2019,
  author    = {Weiss, Lina and Schalow, Linda and Jeltsch, Florian and Geissler, Katja},
  title     = {Experimental evidence for root competition effects on community evenness in one of two phytometer species},
  series = {Journal of plant ecology},
  volume    = {12},
  journal   = {Journal of plant ecology},
  number    = {2},
  publisher = {Oxford Univ. Press},
  address   = {Oxford},
  issn      = {1752-9921},
  doi       = {10.1093/jpe/rty021},
  pages     = {281 -- 291},
  year      = {2019},
  abstract  = {Aims Plant-plant interactions, being positive or negative, are recognized to be key factors in structuring plant communities. However, it is thought that root competition may be less important than shoot competition due to greater size symmetry belowground. Because direct experimental tests on the importance of root competition are scarce, we aim at elucidating whether root competition may have direct or indirect effects on community structure. Indirect effects may occur by altering the overall size asymmetry of competition through root-shoot competitive interactions. Methods We used a phytometer approach to examine the effects of root, shoot and total competition intensity and importance on evenness of experimental plant communities. Thereby two different phytometer species, Festuca brevipila and Dianthus carthusianorum, were grown in small communities of six grassland species over three levels of light and water availability, interacting with neighbouring shoots, roots, both or not at all. Important Findings We found variation in community evenness to be best explained if root and shoot (but not total) competition were considered. However, the effects were species specific: in Dianthus communities increasing root competition increased plant community evenness, while in Festuca communities shoot competition was the driving force of this evenness response. Competition intensities were influenced by environmental conditions in Dianthus, but not in Festuca phytometer plants. While we found no evidence for root-shoot interactions for neither phytometer species root competition in Dianthus communities led to increased allocation to shoots, thereby increasing the potential ability to perform in size-asymmetric competition for light. Our experiment demonstrates the potential role of root competition in structuring plant communities.},
  language  = {en}
}
@article{SchlaegelSignerHerdeetal.2019,
  author    = {Schl{\"a}gel, Ulrike E. and Signer, Johannes and Herde, Antje and Eden, Sophie and Jeltsch, Florian and Eccard, Jana and Dammhahn, Melanie},
  title     = {Estimating interactions between individuals from concurrent animal movements},
  series = {Methods in ecology and evolution : an official journal of the British Ecological Society},
  volume    = {10},
  journal   = {Methods in ecology and evolution : an official journal of the British Ecological Society},
  number    = {8},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {2041-210X},
  doi       = {10.1111/2041-210X.13235},
  pages     = {1234 -- 1245},
  year      = {2019},
  abstract  = {Animal movements arise from complex interactions of individuals with their environment, including both conspecific and heterospecific individuals. Animals may be attracted to each other for mating, social foraging, or information gain, or may keep at a distance from others to avoid aggressive encounters related to, e.g., interference competition, territoriality, or predation. With modern tracking technology, more datasets are emerging that allow to investigate fine-scale interactions between free-ranging individuals from movement data, however, few methods exist to disentangle fine-scale behavioural responses of interacting individuals when these are highly individual-specific. In a framework of step-selection functions, we related movements decisions of individuals to dynamic occurrence distributions of other individuals obtained through kriging of their movement paths. Using simulated data, we tested the method's ability to identify various combinations of attraction, avoidance, and neutrality between individuals, including asymmetric (i.e. non-mutual) behaviours. Additionally, we analysed radio-telemetry data from concurrently tracked small rodents (bank vole, Myodes glareolus) to test whether our method could detect biologically plausible behaviours. We found that our method was able to successfully detect and distinguish between fine-scale interactions (attraction, avoidance, neutrality), even when these were asymmetric between individuals. The method worked best when confounding factors were taken into account in the step-selection function. However, even when failing to do so (e.g. due to missing information), interactions could be reasonably identified. In bank voles, responses depended strongly on the sexes of the involved individuals and matched expectations. Our approach can be combined with conventional uses of step-selection functions to tease apart the various drivers of movement, e.g. the influence of the physical and the social environment. In addition, the method is particularly useful in studying interactions when responses are highly individual-specific, i.e. vary between and towards different individuals, making our method suitable for both single-species and multi-species analyses (e.g. in the context of predation or competition).},
  language  = {en}
}
@article{TeckentrupKramerSchadtJeltsch2019,
  author    = {Teckentrup, Lisa and Kramer-Schadt, Stephanie and Jeltsch, Florian},
  title     = {The risk of ignoring fear: underestimating the effects of habitat loss and fragmentation on biodiversity},
  series = {Landscape ecology},
  volume    = {34},
  journal   = {Landscape ecology},
  number    = {12},
  publisher = {Springer},
  address   = {Dordrecht},
  issn      = {0921-2973},
  doi       = {10.1007/s10980-019-00922-8},
  pages     = {2851 -- 2868},
  year      = {2019},
  language  = {en}
}
@article{BielcikAguilarTriguerosLakovicetal.2019,
  author    = {Bielcik, Milos and Aguilar-Trigueros, Carlos A. and Lakovic, Milica and Jeltsch, Florian and Rillig, Matthias C.},
  title     = {The role of active movement in fungal ecology and community assembly},
  series = {Movement Ecology},
  volume    = {7},
  journal   = {Movement Ecology},
  number    = {1},
  publisher = {BMC},
  address   = {London},
  issn      = {2051-3933},
  doi       = {10.1186/s40462-019-0180-6},
  pages     = {12},
  year      = {2019},
  abstract  = {Movement ecology aims to provide common terminology and an integrative framework of movement research across all groups of organisms. Yet such work has focused on unitary organisms so far, and thus the important group of filamentous fungi has not been considered in this context. With the exception of spore dispersal, movement in filamentous fungi has not been integrated into the movement ecology field. At the same time, the field of fungal ecology has been advancing research on topics like informed growth, mycelial translocations, or fungal highways using its own terminology and frameworks, overlooking the theoretical developments within movement ecology. We provide a conceptual and terminological framework for interdisciplinary collaboration between these two disciplines, and show how both can benefit from closer links: We show how placing the knowledge from fungal biology and ecology into the framework of movement ecology can inspire both theoretical and empirical developments, eventually leading towards a better understanding of fungal ecology and community assembly. Conversely, by a greater focus on movement specificities of filamentous fungi, movement ecology stands to benefit from the challenge to evolve its concepts and terminology towards even greater universality. We show how our concept can be applied for other modular organisms (such as clonal plants and slime molds), and how this can lead towards comparative studies with the relationship between organismal movement and ecosystems in the focus.},
  language  = {en}
}
@misc{RomeroMujalliJeltschTiedemann2019,
  author    = {Romero-Mujalli, Daniel and Jeltsch, Florian and Tiedemann, Ralph},
  title     = {Elevated mutation rates are unlikely to evolve in sexual species, not even under rapid environmental change},
  series = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  number    = {776},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-43905},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-439058},
  pages     = {11},
  year      = {2019},
  abstract  = {Background Organisms are expected to respond to changing environmental conditions through local adaptation, range shift or local extinction. The process of local adaptation can occur by genetic changes or phenotypic plasticity, and becomes especially relevant when dispersal abilities or possibilities are somehow constrained. For genetic changes to occur, mutations are the ultimate source of variation and the mutation rate in terms of a mutator locus can be subject to evolutionary change. Recent findings suggest that the evolution of the mutation rate in a sexual species can advance invasion speed and promote adaptation to novel environmental conditions. Following this idea, this work uses an individual-based model approach to investigate if the mutation rate can also evolve in a sexual species experiencing different conditions of directional climate change, under different scenarios of colored stochastic environmental noise, probability of recombination and of beneficial mutations. The color of the noise mimicked investigating the evolutionary dynamics of the mutation rate in different habitats. Results The results suggest that the mutation rate in a sexual species experiencing directional climate change scenarios can evolve and reach relatively high values mainly under conditions of complete linkage of the mutator locus and the adaptation locus. In contrast, when they are unlinked, the mutation rate can slightly increase only under scenarios where at least 50\% of arising mutations are beneficial and the rate of environmental change is relatively fast. This result is robust under different scenarios of stochastic environmental noise, which supports the observation of no systematic variation in the mutation rate among organisms experiencing different habitats. Conclusions Given that 50\% beneficial mutations may be an unrealistic assumption, and that recombination is ubiquitous in sexual species, the evolution of an elevated mutation rate in a sexual species experiencing directional climate change might be rather unlikely. Furthermore, when the percentage of beneficial mutations and the population size are small, sexual species (especially multicellular ones) producing few offspring may be expected to react to changing environments not by adaptive genetic change, but mainly through plasticity. Without the ability for a plastic response, such species may become - at least locally - extinct.},
  language  = {en}
}
@article{RomeroMujalliJeltschTiedemann2019,
  author    = {Romero-Mujalli, Daniel and Jeltsch, Florian and Tiedemann, Ralph},
  title     = {Elevated mutation rates are unlikely to evolve in sexual species, not even under rapid environmental change},
  series = {BMC Evolutionary Biology},
  volume    = {19},
  journal   = {BMC Evolutionary Biology},
  publisher = {BioMed Central},
  address   = {London},
  issn      = {1471-2148},
  doi       = {10.1186/s12862-019-1494-0},
  pages     = {9},
  year      = {2019},
  abstract  = {Background Organisms are expected to respond to changing environmental conditions through local adaptation, range shift or local extinction. The process of local adaptation can occur by genetic changes or phenotypic plasticity, and becomes especially relevant when dispersal abilities or possibilities are somehow constrained. For genetic changes to occur, mutations are the ultimate source of variation and the mutation rate in terms of a mutator locus can be subject to evolutionary change. Recent findings suggest that the evolution of the mutation rate in a sexual species can advance invasion speed and promote adaptation to novel environmental conditions. Following this idea, this work uses an individual-based model approach to investigate if the mutation rate can also evolve in a sexual species experiencing different conditions of directional climate change, under different scenarios of colored stochastic environmental noise, probability of recombination and of beneficial mutations. The color of the noise mimicked investigating the evolutionary dynamics of the mutation rate in different habitats. Results The results suggest that the mutation rate in a sexual species experiencing directional climate change scenarios can evolve and reach relatively high values mainly under conditions of complete linkage of the mutator locus and the adaptation locus. In contrast, when they are unlinked, the mutation rate can slightly increase only under scenarios where at least 50\% of arising mutations are beneficial and the rate of environmental change is relatively fast. This result is robust under different scenarios of stochastic environmental noise, which supports the observation of no systematic variation in the mutation rate among organisms experiencing different habitats. Conclusions Given that 50\% beneficial mutations may be an unrealistic assumption, and that recombination is ubiquitous in sexual species, the evolution of an elevated mutation rate in a sexual species experiencing directional climate change might be rather unlikely. Furthermore, when the percentage of beneficial mutations and the population size are small, sexual species (especially multicellular ones) producing few offspring may be expected to react to changing environments not by adaptive genetic change, but mainly through plasticity. Without the ability for a plastic response, such species may become - at least locally - extinct.},
  language  = {en}
}
@misc{JeltschGrimmReegetal.2019,
  author    = {Jeltsch, Florian and Grimm, Volker and Reeg, Jette and Schl{\"a}gel, Ulrike E.},
  title     = {Give chance a chance},
  series = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  number    = {742},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-43532},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-435320},
  pages     = {19},
  year      = {2019},
  abstract  = {A large part of biodiversity theory is driven by the basic question of what allows species to coexist in spite of a confined number of niches. A substantial theoretical background to this question is provided by modern coexistence theory (MCT), which rests on mathematical approaches of invasion analysis to categorize underlying mechanisms into factors that reduce either niche overlap (stabilizing mechanisms) or the average fitness differences of species (equalizing mechanisms). While MCT has inspired biodiversity theory in the search for these underlying mechanisms, we feel that the strong focus on coexistence causes a bias toward the most abundant species and neglects the plethora of species that are less abundant and often show high local turnover. Given the more stochastic nature of their occurrence, we advocate a complementary cross-level approach that links individuals, small populations, and communities and explicitly takes into account (1) a more complete inclusion of environmental and demographic stochasticity affecting small populations, (2) intraspecific trait variation and behavioral plasticity, and (3) local heterogeneities, interactions, and feedbacks. Focusing on mechanisms that drive the temporary coviability of species rather than infinite coexistence, we suggest a new approach that could be dubbed coviability analysis (CVA). From a modeling perspective, CVA builds on the merged approaches of individual-based modeling and population viability analysis but extends them to the community level. From an empirical viewpoint, CVA calls for a stronger integration of spatiotemporal data on variability and noise, changing drivers, and interactions at the level of individuals. The resulting large volumes of data from multiple sources could be strongly supported by novel techniques tailored to the discovery of complex patterns in high-dimensional data. By complementing MCT through a stronger focus on the coviability of less common species, this approach can help make modern biodiversity theory more comprehensive, predictive, and relevant for applications.},
  language  = {en}
}
@article{JeltschGrimmReegetal.2019,
  author    = {Jeltsch, Florian and Grimm, Volker and Reeg, Jette and Schl{\"a}gel, Ulrike E.},
  title     = {Give chance a chance},
  series = {Ecosphere},
  volume    = {10},
  journal   = {Ecosphere},
  number    = {5},
  publisher = {ESA},
  address   = {Ithaca, NY},
  issn      = {2150-8925},
  doi       = {10.1002/ecs2.2700},
  pages     = {19},
  year      = {2019},
  abstract  = {A large part of biodiversity theory is driven by the basic question of what allows species to coexist in spite of a confined number of niches. A substantial theoretical background to this question is provided by modern coexistence theory (MCT), which rests on mathematical approaches of invasion analysis to categorize underlying mechanisms into factors that reduce either niche overlap (stabilizing mechanisms) or the average fitness differences of species (equalizing mechanisms). While MCT has inspired biodiversity theory in the search for these underlying mechanisms, we feel that the strong focus on coexistence causes a bias toward the most abundant species and neglects the plethora of species that are less abundant and often show high local turnover. Given the more stochastic nature of their occurrence, we advocate a complementary cross-level approach that links individuals, small populations, and communities and explicitly takes into account (1) a more complete inclusion of environmental and demographic stochasticity affecting small populations, (2) intraspecific trait variation and behavioral plasticity, and (3) local heterogeneities, interactions, and feedbacks. Focusing on mechanisms that drive the temporary coviability of species rather than infinite coexistence, we suggest a new approach that could be dubbed coviability analysis (CVA). From a modeling perspective, CVA builds on the merged approaches of individual-based modeling and population viability analysis but extends them to the community level. From an empirical viewpoint, CVA calls for a stronger integration of spatiotemporal data on variability and noise, changing drivers, and interactions at the level of individuals. The resulting large volumes of data from multiple sources could be strongly supported by novel techniques tailored to the discovery of complex patterns in high-dimensional data. By complementing MCT through a stronger focus on the coviability of less common species, this approach can help make modern biodiversity theory more comprehensive, predictive, and relevant for applications.},
  language  = {en}
}
@misc{ReegHeineMihanetal.2019,
  author    = {Reeg, Jette and Heine, Simon and Mihan, Christine and McGee, Sean and Preuss, Thomas G. and Jeltsch, Florian},
  title     = {Simulation of herbicide impacts on a plant community},
  series = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  number    = {528},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-42303},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-423039},
  pages     = {16},
  year      = {2019},
  abstract  = {Background Semi-natural plant communities such as field boundaries play an important ecological role in agricultural landscapes, e.g., provision of refuge for plant and other species, food web support or habitat connectivity. To prevent undesired effects of herbicide applications on these communities and their structure, the registration and application are regulated by risk assessment schemes in many industrialized countries. Standardized individual-level greenhouse experiments are conducted on a selection of crop and wild plant species to characterize the effects of herbicide loads potentially reaching off-field areas on non-target plants. Uncertainties regarding the protectiveness of such approaches to risk assessment might be addressed by assessment factors that are often under discussion. As an alternative approach, plant community models can be used to predict potential effects on plant communities of interest based on extrapolation of the individual-level effects measured in the standardized greenhouse experiments. In this study, we analyzed the reliability and adequacy of the plant community model IBC-grass (individual-based plant community model for grasslands) by comparing model predictions with empirically measured effects at the plant community level. Results We showed that the effects predicted by the model IBC-grass were in accordance with the empirical data. Based on the species-specific dose responses (calculated from empirical effects in monocultures measured 4 weeks after application), the model was able to realistically predict short-term herbicide impacts on communities when compared to empirical data. Conclusion The results presented in this study demonstrate an approach how the current standard greenhouse experiments—measuring herbicide impacts on individual-level—can be coupled with the model IBC-grass to estimate effects on plant community level. In this way, it can be used as a tool in ecological risk assessment.},
  language  = {en}
}