TY  - JOUR
A1  - Brose, Ulrich
A1  - Tielbörger, Katja
T1  - Subtle differences in environmental stress along a flooding gradient affect the importance of inter-specific competition in an annual plant community
N2  - Empirical evidence suggests that the direction and intensity of plant-plant interactions may depend on the favourability of the environment. Previous studies have mainly focused on steep gradients of environmental stress or disturbance, while the interplay of competition and environment has not been tested for subtle environmental differences. Here, we present results from a study on plant communities of temporary wetlands in East-German farmland. Due to yearly ploughing in autumn, the vegetation is composed of annual species. Flooding does not affect adult plants and the elevation on the gradient expresses differences in the length of the growing season rather than in disturbance intensity or severe environmental stress. We tested whether such subtle differences in environmental stress may affect the importance of interspecific competition by the dominant species. Two treatments were applied at two elevations: removal of the dominant species (Matricaria maritima ssp. inodora) and reciprocal transplants of the seed-bank of the two elevations. At both elevations, removal of Matricaria inodora led to an increase in total species richness and number of wetland species, but the effects were substantially stronger at high elevations. Removal and the elevation on the flooding gradient significantly influenced the plant community composition. In particular, the weed communities became more similar to the wetland communities after the removal. Transplanted weed species did not emerge at low elevations. While two of four target species had significantly higher densities after the removal at high elevations, none of them was influenced by removal at low elevations. This indicates that, consistent with previous studies from other habitat types, competition by the dominant species was more intense under conditions of low environmental stress. The overall results suggest that both flooding as well as interspecific competition are important in structuring the plant communities along the freshwater gradient studied
Y1  - 2005
SN  - 1385-0237
ER  - 
TY  - JOUR
A1  - Ryser, Remo
A1  - Häussler, Johanna
A1  - Stark, Markus
A1  - Brose, Ulrich
A1  - Rall, Björn C.
A1  - Guill, Christian
T1  - The biggest losers: habitat isolation deconsructs complex food webs from top to bottom
JF  - Proceedings of the Royal Society of London : B, Biological sciences
N2  - Habitat fragmentation threatens global biodiversity. To date, there is only limited understanding of how the different aspects of habitat fragmentation (habitat loss, number of fragments and isolation) affect species diversity within complex ecological networks such as food webs. Here, we present a dynamic and spatially explicit food web model which integrates complex food web dynamics at the local scale and species-specific dispersal dynamics at the landscape scale, allowing us to study the interplay of local and spatial processes in metacommunities. We here explore how the number of habitat patches, i.e. the number of fragments, and an increase of habitat isolation affect the species diversity patterns of complex food webs (alpha-,beta-,gamma-, diversities). We specifically test whether there is a trophic dependency in the effect of these two factors on species diversity. In our model, habitat isolation is the main driver causing species loss and diversity decline. Our results emphasize that large-bodied consumer species at high trophic positions go extinct faster than smaller species at lower trophic levels, despite being superior dispersers that connect fragmented landscapes better. We attribute the loss of top species to a combined effect of higher biomass loss during dispersal with increasing habitat isolation in general, and the associated energy limitation in highly fragmented landscapes, preventing higher trophic levels to persist. To maintain trophic-complex and species-rich communities calls for effective conservation planning which considers the interdependence of trophic and spatial dynamics as well as the spatial context of a landscape and its energy availability.
KW  - food webs
KW  - allometry
KW  - bioenergetic model
KW  - metacommunity dynamics
KW  - dispersal mortality
KW  - landscape structure
Y1  - 2019
U6  - https://doi.org/10.1098/rspb.2019.1177
SN  - 0962-8452
SN  - 1471-2954
VL  - 286
IS  - 1908
PB  - Royal Society
CY  - London
ER  - 
TY  - JOUR
A1  - Pennekamp, Frank
A1  - Iles, Alison C.
A1  - Garland, Joshua
A1  - Brennan, Georgina
A1  - Brose, Ulrich
A1  - Gaedke, Ursula
A1  - Jacob, Ute
A1  - Kratina, Pavel
A1  - Matthews, Blake
A1  - Munch, Stephan
A1  - Novak, Mark
A1  - Palamara, Gian Marco
A1  - Rall, Bjorn C.
A1  - Rosenbaum, Benjamin
A1  - Tabi, Andrea
A1  - Ward, Colette
A1  - Williams, Richard
A1  - Ye, Hao
A1  - Petchey, Owen L.
T1  - The intrinsic predictability of ecological time series and its potential to guide forecasting
JF  - Ecological monographs : a publication of the Ecological Society of America.
KW  - empirical dynamic modelling
KW  - forecasting
KW  - information theory
KW  - permutation entropy
KW  - population dynamics
KW  - time series analysis
Y1  - 2019
U6  - https://doi.org/10.1002/ecm.1359
SN  - 0012-9615
SN  - 1557-7015
VL  - 89
IS  - 2
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Kefi, Sonia
A1  - Berlow, Eric L.
A1  - Wieters, Evie A.
A1  - Navarrete, Sergio A.
A1  - Petchey, Owen L.
A1  - Wood, Spencer A.
A1  - Boit, Alice
A1  - Joppa, Lucas N.
A1  - Lafferty, Kevin D.
A1  - Williams, Richard J.
A1  - Martinez, Neo D.
A1  - Menge, Bruce A.
A1  - Blanchette, Carol A.
A1  - Iles, Alison C.
A1  - Brose, Ulrich
T1  - More than a meal ... integrating non-feeding interactions into food webs
JF  - Ecology letters
N2  - Organisms eating each other are only one of many types of well documented and important interactions among species. Other such types include habitat modification, predator interference and facilitation. However, ecological network research has been typically limited to either pure food webs or to networks of only a few (<3) interaction types. The great diversity of non-trophic interactions observed in nature has been poorly addressed by ecologists and largely excluded from network theory. Herein, we propose a conceptual framework that organises this diversity into three main functional classes defined by how they modify specific parameters in a dynamic food web model. This approach provides a path forward for incorporating non-trophic interactions in traditional food web models and offers a new perspective on tackling ecological complexity that should stimulate both theoretical and empirical approaches to understanding the patterns and dynamics of diverse species interactions in nature.
KW  - Ecological network
KW  - ecosystem engineering
KW  - facilitation
KW  - food web
KW  - interaction modification
KW  - non-trophic interactions
KW  - trophic interactions
Y1  - 2012
U6  - https://doi.org/10.1111/j.1461-0248.2011.01732.x
SN  - 1461-023X
VL  - 15
IS  - 4
SP  - 291
EP  - 300
PB  - Wiley-Blackwell
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Curtsdotter, Alva
A1  - Binzer, Amrei
A1  - Brose, Ulrich
A1  - de Castro, Francisco
A1  - Ebenman, Bo
A1  - Ekloef, Anna
A1  - Riede, Jens O.
A1  - Thierry, Aaron
A1  - Rall, Bjoern C.
T1  - Robustness to secondary extinctions comparing trait-based sequential deletions in static and dynamic food webs
JF  - Basic and applied ecology : Journal of the Gesellschaft für Ökologie
N2  - The loss of species from ecological communities can unleash a cascade of secondary extinctions, the risk and extent of which are likely to depend on the traits of the species that are lost from the community. To identify species traits that have the greatest impact on food web robustness to species loss we here subject allometrically scaled, dynamical food web models to several deletion sequences based on species' connectivity, generality, vulnerability or body mass. Further, to evaluate the relative importance of dynamical to topological effects we compare robustness between dynamical and purely topological models. This comparison reveals that the topological approach overestimates robustness in general and for certain sequences in particular. Top-down directed sequences have no or very low impact on robustness in topological analyses, while the dynamical analysis reveals that they may be as important as high-impact bottom-up directed sequences. Moreover, there are no deletion sequences that result, on average, in no or very few secondary extinctions in the dynamical approach. Instead, the least detrimental sequence in the dynamical approach yields an average robustness similar to the most detrimental (non-basal) deletion sequence in the topological approach. Hence, a topological analysis may lead to erroneous conclusions concerning both the relative and the absolute importance of different species traits for robustness. The dynamical sequential deletion analysis shows that food webs are least robust to the loss of species that have many trophic links or that occupy low trophic levels. In contrast to previous studies we can infer, albeit indirectly, that secondary extinctions were triggered by both bottom-up and top-down cascades.
KW  - Species loss
KW  - Extinction cascades
KW  - Top-down effect
KW  - Bottom-up effect
KW  - Stability
KW  - Body size
KW  - Trophic interactions
KW  - Vulnerability
KW  - Generality
KW  - Keystone species
Y1  - 2011
U6  - https://doi.org/10.1016/j.baae.2011.09.008
SN  - 1439-1791
VL  - 12
IS  - 7
SP  - 571
EP  - 580
PB  - Elsevier
CY  - Jena
ER  - 
TY  - JOUR
A1  - Riede, Jens O.
A1  - Binzer, Amrei
A1  - Brose, Ulrich
A1  - de Castro, Francisco
A1  - Curtsdotter, Alva
A1  - Rall, Bjoern C.
A1  - Ekloef, Anna
T1  - Size-based food web characteristics govern the response to species extinctions
JF  - Basic and applied ecology : Journal of the Gesellschaft für Ökologie
N2  - How ecological communities react to species extinctions is a long-standing yet current question in ecology. The species constituting the basic units of ecosystems interact with each other forming complex networks of trophic relationships and the characteristics of these networks are highly important for the consequences of species extinction. Here we take a more general approach and analyze a broad range of network characteristics and their role in determining food web susceptibility to secondary extinctions. We extend previous studies, that have focused on the consequences of topological and dynamical food web parameters for food web robustness, by also defining network-wide characteristics depending on the relationships between the distribution of species body masses and other species characteristics. We use a bioenergetic dynamical model to simulate realistically structured model food webs that differ in their structural and dynamical properties as well as their size structure. In order to measure food web robustness we calculated the proportion of species going secondarily extinct. A multiple regression analysis was then used to fit a general model relating the proportion of species going secondarily extinct to the measured food web properties. Our results show that there are multiple factors from all three groups of food web characteristics that affect food web robustness. However, we find the most striking effect was related to the body mass abundance relationship which points to the importance of body mass relationships for food web stability.
KW  - Body mass-abundance
KW  - Connectance
KW  - Food web robustness
KW  - Hill exponent
KW  - Size structure
KW  - Secondary extinctions
Y1  - 2011
U6  - https://doi.org/10.1016/j.baae.2011.09.006
SN  - 1439-1791
VL  - 12
IS  - 7
SP  - 581
EP  - 589
PB  - Elsevier
CY  - Jena
ER  - 
TY  - JOUR
A1  - Binzer, Amrei
A1  - Brose, Ulrich
A1  - Curtsdotter, Alva
A1  - Ekloef, Anna
A1  - Rall, Bjoern C.
A1  - Riede, Jens O.
A1  - de Castro, Francisco
T1  - The susceptibility of species to extinctions in model communities
JF  - Basic and applied ecology : Journal of the Gesellschaft für Ökologie
N2  - Despite the fact that the loss of a species from a community has the potential to cause a dramatic decline in biodiversity, for example through cascades of secondary extinctions, little is known about the factors contributing to the extinction risk of any particular species. Here we expand earlier modeling approaches using a dynamic food-web model that accounts for bottom-up as well as top-down effects. We investigate what factors influence a species' extinction risk and time to extinction of the non-persistent species.
 We identified three basic properties that affect a species' risk of extinction. The highest extinction risk is born by species with (1) low energy input (e.g. high trophic level), (2) susceptibility to the loss of energy pathways (e.g. specialists with few prey species) and (3) dynamic instability (e.g. low Hill exponent and reliance on homogeneous energy channels when feeding on similarly sized prey).
 Interestingly, and different from field studies, we found that the trophic level and not the body mass of a species influences its extinction risk. On the other hand, body mass is the single most important factor determining the time to extinction of a species, resulting in small species dying first. This suggests that in the field the trophic level might have more influence on the extinction risk than presently recognized.
KW  - Extinction risk
KW  - Allometry
KW  - Dynamic modeling
Y1  - 2011
U6  - https://doi.org/10.1016/j.baae.2011.09.002
SN  - 1439-1791
VL  - 12
IS  - 7
SP  - 590
EP  - 599
PB  - Elsevier
CY  - Jena
ER  - 
TY  - JOUR
A1  - Schneider, Florian D.
A1  - Brose, Ulrich
A1  - Rall, Björn C.
A1  - Guill, Christian
T1  - Animal diversity and ecosystem functioning in dynamic food webs
JF  - Nature Communications
N2  - Species diversity is changing globally and locally, but the complexity of ecological communities hampers a general understanding of the consequences of animal species loss on ecosystem functioning. High animal diversity increases complementarity of herbivores but also increases feeding rates within the consumer guild. Depending on the balance of these counteracting mechanisms, species-rich animal communities may put plants under top-down control or may release them from grazing pressure. Using a dynamic food-web model with body-mass constraints, we simulate ecosystem functions of 20,000 communities of varying animal diversity. We show that diverse animal communities accumulate more biomass and are more exploitative on plants, despite their higher rates of intra-guild predation. However, they do not reduce plant biomass because the communities are composed of larger, and thus energetically more efficient, plant and animal species. This plasticity of community body-size structure reconciles the debate on the consequences of animal species loss for primary productivity.
Y1  - 2016
U6  - https://doi.org/10.1038/ncomms12718
SN  - 2041-1723
VL  - 7
SP  - 3129
EP  - 3138
PB  - Nature Publ. Group
CY  - London
ER  - 
TY  - JOUR
A1  - Binzer, Amrei
A1  - Guill, Christian
A1  - Rall, Björn C.
A1  - Brose, Ulrich
T1  - Interactive effects of warming, eutrophication and size structure: impacts on biodiversity and food-web structure
JF  - Global change biology
N2  - Warming and eutrophication are two of the most important global change stressors for natural ecosystems, but their interaction is poorly understood. We used a dynamic model of complex, size-structured food webs to assess interactive effects on diversity and network structure. We found antagonistic impacts: Warming increases diversity in eutrophic systems and decreases it in oligotrophic systems. These effects interact with the community size structure: Communities of similarly sized species such as parasitoid-host systems are stabilized by warming and destabilized by eutrophication, whereas the diversity of size-structured predator-prey networks decreases strongly with warming, but decreases only weakly with eutrophication. Nonrandom extinction risks for generalists and specialists lead to higher connectance in networks without size structure and lower connectance in size-structured communities. Overall, our results unravel interactive impacts of warming and eutrophication and suggest that size structure may serve as an important proxy for predicting the community sensitivity to these global change stressors.
KW  - complex food webs
KW  - extinctions
KW  - generalists
KW  - global change
KW  - size structure
KW  - specialists
Y1  - 2016
U6  - https://doi.org/10.1111/gcb.13086
SN  - 1354-1013
SN  - 1365-2486
VL  - 22
SP  - 220
EP  - 227
PB  - Wiley-Blackwell
CY  - Hoboken
ER  - 
TY  - THES
A1  - Brose, Ulrich
T1  - Artendiversität der Pflanzen- und Laufkäfergemeinschaften (Coleoptera, Carabidae) von Naßstelle auf mehreren räumlichen Skalenebenen
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Gross, Thilo
A1  - Allhoff, Korinna Theresa
A1  - Blasius, Bernd
A1  - Brose, Ulrich
A1  - Drossel, Barbara
A1  - Fahimipour, Ashkaan K.
A1  - Guill, Christian
A1  - Yeakel, Justin D.
A1  - Zeng, Fanqi
T1  - Modern models of trophic meta-communities
JF  - Philosophical transactions of the Royal Society of London : B, Biological sciences
N2  - Dispersal and foodweb dynamics have long been studied in separate models. However, over the past decades, it has become abundantly clear that there are intricate interactions between local dynamics and spatial patterns. Trophic meta-communities, i.e. meta-foodwebs, are very complex systems that exhibit complex and often counterintuitive dynamics. Over the past decade, a broad range of modelling approaches have been used to study these systems. In this paper, we review these approaches and the insights that they have revealed. We focus particularly on recent papers that study trophic interactions in spatially extensive settings and highlight the common themes that emerged in different models. There is overwhelming evidence that dispersal (and particularly intermediate levels of dispersal) benefits the maintenance of biodiversity in several different ways. Moreover, some insights have been gained into the effect of different habitat topologies, but these results also show that the exact relationships are much more complex than previously thought, highlighting the need for further research in this area. This article is part of the theme issue 'Integrative research perspectives on marine conservation'.
KW  - dispersal
KW  - meta-community
KW  - foodweb
Y1  - 2020
U6  - https://doi.org/10.1098/rstb.2019.0455
SN  - 0962-8436
SN  - 1471-2970
VL  - 375
IS  - 1814
PB  - Royal Society
CY  - London
ER  - 
TY  - JOUR
A1  - Jeltsch, Florian
A1  - Tews, Jörg
A1  - Brose, Ulrich
A1  - Grimm, Volker
A1  - Tielbörger, Katja
A1  - Wichmann, Matthias
A1  - Schwager, Monika
T1  - Animal species diversity driven by habitat heterogeneity/diversity : the importance of keystone structures
N2  - In a selected literature survey we reviewed studies on the habitat heterogeneity-animal species diversity relationship and evaluated whether there are uncertainties and biases in its empirical support. We reviewed 85 publications for the period 1960-2003. We screened each publication for terms that were used to define habitat heterogeneity, the animal species group and ecosystem studied, the definition of the structural variable, the measurement of vegetation structure and the temporal and spatial scale of the study. The majority of studies found a positive correlation between habitat heterogeneity/diversity and animal species diversity. However, empirical support for this relationship is drastically biased towards studies of vertebrates and habitats under anthropogenic influence. In this paper we show that ecological effects of habitat heterogeneity may vary considerably between species groups depending on whether structural attributes are perceived as heterogeneity or fragmentation. Possible effects may also vary relative to the structural variable measured. Based upon this, we introduce a classification framework that may be used for across-studies comparisons. Moreover, the effect of habitat heterogeneity for one species group may differ in relation to the spatial scale. In several studies, however, different species groups are closely linked to 'keystone structures' that determine animal species diversity by their presence. Detecting crucial keystone structures of the vegetation has profound implications for nature conservation and biodiversity management.
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Jeltsch, Florian
A1  - Blaum, Niels
A1  - Brose, Ulrich
A1  - Chipperfield, Joseph D.
A1  - Clough, Yann
A1  - Farwig, Nina
A1  - Geissler, Katja
A1  - Graham, Catherine H.
A1  - Grimm, Volker
A1  - Hickler, Thomas
A1  - Huth, Andreas
A1  - May, Felix
A1  - Meyer, Katrin M.
A1  - Pagel, Jörn
A1  - Reineking, Björn
A1  - Rillig, Matthias C.
A1  - Shea, Katriona
A1  - Schurr, Frank Martin
A1  - Schroeder, Boris
A1  - Tielbörger, Katja
A1  - Weiss, Lina
A1  - Wiegand, Kerstin
A1  - Wiegand, Thorsten
A1  - Wirth, Christian
A1  - Zurell, Damaris
T1  - How can we bring together empiricists and modellers in functional biodiversity research?
JF  - Basic and applied ecology : Journal of the Gesellschaft für Ökologie
N2  - Improving our understanding of biodiversity and ecosystem functioning and our capacity to inform ecosystem management requires an integrated framework for functional biodiversity research (FBR). However, adequate integration among empirical approaches (monitoring and experimental) and modelling has rarely been achieved in FBR. We offer an appraisal of the issues involved and chart a course towards enhanced integration. A major element of this path is the joint orientation towards the continuous refinement of a theoretical framework for FBR that links theory testing and generalization with applied research oriented towards the conservation of biodiversity and ecosystem functioning. We further emphasize existing decision-making frameworks as suitable instruments to practically merge these different aims of FBR and bring them into application. This integrated framework requires joint research planning, and should improve communication and stimulate collaboration between modellers and empiricists, thereby overcoming existing reservations and prejudices. The implementation of this integrative research agenda for FBR requires an adaptation in most national and international funding schemes in order to accommodate such joint teams and their more complex structures and data needs.
KW  - Biodiversity theory
KW  - Biodiversity experiments
KW  - Conservation management
KW  - Decision-making
KW  - Ecosystem functions and services
KW  - Forecasting
KW  - Functional traits
KW  - Global change
KW  - Monitoring programmes
KW  - Interdisciplinarity
Y1  - 2013
U6  - https://doi.org/10.1016/j.baae.2013.01.001
SN  - 1439-1791
VL  - 14
IS  - 2
SP  - 93
EP  - 101
PB  - Elsevier
CY  - Jena
ER  -