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29th Systems Science Colloquium

Winter semester 2022/23

The colloquium takes place on Wednesdays from 16:15 to max. 17:45.

This semester, there is a mixture of either onsite (Präsenz) or online colloquia.

• Onsite colloquia take place in room 35/E16 (biology building, Barbarastraße 11).
• Online colloquia take place via a videoconference in BigBlueButton.
  Link: https://studip.uni-osnabrueck.de/plugins.php/meetingplugin/room/index/370d530d07448f21d454ef7315b4bd79/40c25fbac09f1fdd8b37d0d3f73d0bc2?cancel_login=1

Please see the program below for which colloquia will be held onsite or online.

PDF file of the program for download

Program

30 November 2022, online

Dr. Katrin Prager, University of Aberdeen, School of Geosciences (UK)
How can we use policy instruments to support farmer cooperation for environmental benefits? - Learning from the Countryside Stewardship Facilitation Fund

14 December 2022, onsite

Dr. Christian Guill, University of Potsdam, Ecology and Ecosystem Modelling
Self-organised pattern formation and the biodiversity of metacommunities

21 December 2022, online

Dr. Silvia Pieper, German Environment Agency
Moving to a system-based approach in environmental risk assessment

11 January 2023, onsite

Dr. Wibke Busch, Helmholtz Centre for Environmental Research, UFZ Leipzig
Chemical hazard assessment with toxicogenomic approaches - from snapshot observations to comprehensive mixture effect predictions on organism scale

18 January 2023, onsite

Dr. Viktoriia Radchuk, Leibniz Institute for Zoo and Wildlife Research, Department of Ecological Dynamics
Phenotypic and population responses of animals to climate change

25 January 2023, onsite

Prof. Dr. Charles Palmer, London School of Economics and Political Science, Department of Geography and Environment (UK)
Forest co-management, food security and poverty traps

01 February 2023, t.b.a.

Prof. Dr. Manuel E. Ortiz-Santaliestra, Institute for Game and Wildlife Research, Universidad de Castilla-La Mancha (Spain)
Bottom-up approaches in environmental risk assessment of pesticides to wildlife

08 February 2023, onsite

Dr. Nadja Rüger, German Centre for Integrative Biodiversity Research (iDiv), Leipzig
The essence of diversity: A predictive demographic modeling framework for the dynamics of species-rich tropical forests

Abstracts of presentations

30 November 2022
Dr. Katrin Prager, University of Aberdeen, School of Geosciences (UK)

How can we use policy instruments to support farmer cooperation for environmental benefits? - Learning from the Countryside Stewardship Facilitation Fund
Farmers cooperate in different ways and for different purposes, but cooperating in the implementation of agri-environmental measures is rare, and represents a different, more unique, case in relation to cooperation. Nevertheless, it is attractive to policy makers to supplement agri-environment schemes (AES) with mechanisms to incentivise farmer cooperation in order to achieve management that is coordinated at ‘landscape-scale’ and thus more effective for certain ecosystem services such as water quality, and biodiversity. In this talk, I will introduce the Countryside Stewardship Facilitation Fund (CSFF) in England as a policy intervention to develop cooperation amongst farmers and agree the agri-environmental management priorities that they plan to take forward across their holdings. Data from empirical research on the actual operation of six CSFF-funded groups in Cumbria and East Anglia was analysed from a social capital and collective action perspective. I found that key elements of social capital (connectedness, trust, norms) differed between cases, leading to different starting points for establishing groups. The resulting cooperation in agri-environmental management also varied depending on pre-existing networks. The CSFF supported steps to increase the capacity of individuals (and in some cases groups) to deliver agri-environmental outcomes via a facilitator, but struggled to create self-sustaining groups of farmers collaborating on agri-environmental management. The design of similar policy interventions needs to be explicit what kind of farmer cooperation is aimed for. It also needs to take into account the time required for building the prerequisite social capital, tensions between priorities of farmer-led groups and state-funded AES, and trade-offs between group cohesion and landscape-scale working.

14 December 2022
Dr. Christian Guill, University of Potsdam, Ecology and Ecosystem Modelling

Self-organised pattern formation and the biodiversity of metacommunities
Ecological communities are naturally distributed in space, which leads to the formation of so-called metacommunities. Within these, the populations of species interact on different spatial scales: locally, populations of different species interact via feeding and competition, while regionally, populations on different habitat patches are connected via dispersal. The interplay of these different types of interactions can lead to self-organised formation of patterns in the species' biomass distributions, i.e., despite spatially homogeneous environmental conditions, heterogeneous biomass distributions emerge. This phenomenon and its implications have been observed and theoretically analysed in a number of ecological systems, most notably in dryland vegetation. The underlying theory usually assumes that space is homogeneous, continuous, and isotropic. Recently, however, the theory has been extended to network-organised systems, which are often a better approximation of today's fragmented landscapes.
I will first introduce how the onset of self-organised pattern formation via Turing instabilities on networks of habitat patches is mathematically analysed. Then, I will present our results on the effects of self-organised pattern formation in a generic ecosystem model, where a potentially diverse community of autotrophs (plants or algae) consumes an abiotic nutrient and is itself exploited by herbivores. When the spatial dimension is neglected and pattern formation cannot occur, diversity always diminishes over time due to stabilising selection. In contrast, in a metacommunity context, dispersal of the species and diffusion of the nutrients can destabilise the local communities and complex spatio-­temporal patterns in the species’ abundances and the nutrient concentrations emerge. This affects the diversity of both trophic levels. On the one hand, the spatial and temporal variations in resource availability and consumption pressure create highly heterogeneous fitness landscapes. This leads to biomass-trait feedbacks that drastically enhance the functional diversity of the autotroph communities. On the other hand, self-organised pattern formation allows herbivores with different competitive abilities to coexist even if the plant diversity is reduced to just a single dominant type. Normally, coexistence is not possible under these circumstances due to competitive exclusion, but emergent heterogeneity between neighbouring patches creates an additional niche dimension as fitness in the metacommunity is also affected by the dispersal strategy.

21 December 2022
Dr. Silvia Pieper, German Environment Agency

Moving to a system-based approach in environmental risk assessment
Prospective assessment of chemical impacts on the environment are currently performed in isolation. Regulatory ‘silos’ exist for chemicals used for different purposes (e.g., pesticides, pharmaceuticals, industrial chemicals), and within the different approaches, chemical risks are mostly assessed for single substances in single uses and for single organism groups. As a consequence, there is no assessment of overall impacts on protection targets and methods are not harmonized. The need to move to a more holistic approach has been recognized up to the European level, as laid down in the new Strategies under the European Green Deal and recent activities of several European Agencies. With reference to a strategic activity of the European Food Safety Authority (EFSA), I will report on the process of developing a roadmap to a systems-based approach for the environmental risk assessment (ERA) of pesticides. My focus will be on the consequences of the currently adopted ERA - exemplarily for terrestrial ecosystems- on the needs identified and the proposed way forward to a more integrated assessment of chemical risks.

11 January 2023
Dr. Wibke Busch, Helmholtz Centre for Environmental Research, UFZ Leipzig

Chemical hazard assessment with toxicogenomic approaches - from snapshot observations to comprehensive mixture effect predictions on organism scale
Humans and environmental organisms are constantly exposed to complex mixtures of chemicals. Extending our knowledge about the combined effects of chemicals is thus essential for assessing the potential consequences of these exposures. In this context, comprehensive molecular readouts as retrieved by omics techniques are advancing our understanding of the diversity of effects upon chemical exposure. In this seminar, I will show how we investigated the predictability of chemical mixture effects on the whole-transcriptome scale in the zebrafish embryo, a model organism in toxicology. To predict concentration- and time-resolved whole-transcriptome responses to mixture exposures, we adopted the mixture concept of concentration addition. Comparisons of the predictions with observations showed that reasonable estimates for the effects induced by the mixture exposure on the whole transcriptome organism scale were obtained. Overall, we demonstrate that using a concentration- and time-resolved approach, the occurrence and size of combined effects of chemicals may be predicted comprehensively at the molecular scale and that this allows discrimination between chemical-agnostic and global stress responses relevant for adverse outcome and chemical risk assessment.

18 January 2023
Dr. Viktoriia Radchuk, Leibniz Institute for Zoo and Wildlife Research, Department of Ecological Dynamics

Phenotypic and population responses of animals to climate change
Climate change poses multiple threats to biodiversity, with one affected facet of biodiversity being phenotypic traits. Examples of phenotypic traits are phenology, i.e. timing of biological events (e.g. egg laying date, migration date) and morphology (e.g. body size). Though these traits are widely reported to respond to climate change, we still do not know to what extent such responses are adaptive, that is to what degree those responses confer fitness benefits. We addressed this question in a meta-analysis using published studies on animals globally. We found that, on average, phenological advances are adaptive but incomplete, meaning the rate at which they occur is not fast enough to ensure long-term population persistence. Along with phenotypic responses, animals respond to changing climate by changes in population numbers. Yet, what are the consequences of climate-driven changes in traits for population growth rate remains to be answered. To do so, we assembled a dataset on 308 published studies across 74 animal species. Each study represented a time series of phenotypic traits (phenological and morphological) and population sizes and was matched to precipitation and temperature. We found high heterogeneity of phenotypic responses to both climate drivers. Further, phenological responses to temperature on average buffered population growth rate across species but this was not the case for phenological responses to precipitation or morphological responses to either climate driver. For a non-negligible proportion of studies, the relations between phenotypic traits and population growth rate were non-linear. This finding inspired a simulation study to assess how such nonlinearity affects population stability. Our results suggest that sigmoidal relations (either of climate and trait or trait and demographic rate) lead to more stable populations irrespective of species life history. Altogether, our research represents first steps towards understanding the complexity of animal responses to climate, by combining global datasets and simulations.

25 January 2023
Prof. Dr. Charles Palmer, London School of Economics and Political Science, Department of Geography and Environment (UK)

Forest co-management, food security and poverty traps
Implemented globally since the 1990s, co-management involves the devolution and transfer of common-pool resource rights from governments to rural communities. In practice, this process often involves efforts, instigated by governments and other stakeholders, to improve livelihoods and reduce poverty via the sustainable use and conservation of resources. Quantitative empirical evidence to date suggests mixed effects with respect to forest co-management’s impacts on poverty and conservation, including in Sub-Saharan Africa. With a focus on Malawi, our study aims to fill two gaps in the literature. First, to better understand the mechanisms by which co-management influences poverty and to provide empirical evidence of potential mechanisms. Second, to investigate the distributional implications of co-management and within this context, examine whether the scheme triggered or sustained geographically-determined poverty traps. Similar to other countries with high forest cover and livelihoods dependent on resource extraction, Malawi began the process of implementing forest co-management in the 1990s. This process culminated with the Improved Forest Management for Sustainable Livelihoods Programme (IFMSLP). The IFMSLP aimed to increase household incomes and improve food security through sustainable forest management. To infer causality between the IFMSLP and its stated goals, we first apply a differences-in-differences framework to a panel dataset and evaluate the policy’s impacts on households two and five years after the end of the IFMSLP. Within this framework, we then explore the programme’s heterogeneous effects, the mechanisms by which these effects materialized, and the relationship between the programme and potential poverty traps. Finally, a discussion of the latter is extended to consider the policy’s impacts on Malawi’s forests.

01 February 2023
Prof. Dr. Manuel E. Ortiz-Santaliestra, Institute for Game and Wildlife Research, Universidad de Castilla-La Mancha (Spain)

Bottom-up approaches in environmental risk assessment of pesticides to wildlife
Application of pesticides is recognized as one of the main reasons for declines of farmland biodiversity. Despite regulatory risk assessment procedures are conducted to avoid unacceptable damage to wildlife resulting from environmental release of pesticides, there is evidence that protection is not guaranteed under certain scenarios. One of main problems behind the sometimes-low efficiency of environmental risk assessment of pesticides is that the procedures are usually limited to simplistic scenarios and ignore the complexity of the ecosystems. Scaling-up ecotoxicological data to the ecological level is therefore necessary to increase the relevance of the research results and to maximize their applicability to develop an efficient and protective risk assessment for wildlife. Our team has been investigating, for more than one decade, on different case studies about incidents in wildlife associated with pesticide use, from the initial description of toxicity and hazards to the characterization of population-level effects. Over the course of those studies, the abovementioned need to focus on ecologically relevant assessments has been revealed, and in this context we continue working to provide appropriate tools for improvement of risk assessment efficacy. During this seminar, we will review some of these case studies reflecting different problematics; on the one hand, that of an under-represented group in risk assessment procedures, such as amphibians, which are however highly sensitive to, and globally threatened by environmental pollution. On the other hand, the case of pesticide-coated seeds and granivorous birds, which represents a very particular risk when as animals become susceptible of ingesting toxic doses of pesticides in a short term when consuming these seeds. Strategies to integrate individual- with population-based effects will be reviewed and discussed.

08 February 2023
Dr. Nadja Rüger, German Centre for Integrative Biodiversity Research (iDiv), Leipzig

The essence of diversity: A predictive demographic modeling framework for the dynamics of species-rich tropical forests
Understanding tropical forest dynamics and planning for their sustainable management require efficient, yet accurate, predictions of the joint dynamics of hundreds of tree species. With increasing information on tropical tree life histories, our predictive understanding is no longer limited by species data but by the ability of existing models to make use of it. Using a demographic forest model, I show that the dynamics of a tropical forest in Panama can be accurately predicted by representing tree diversity (hundreds of species) with only five functional groups spanning two essential demographic trade-offs—the growth-survival and stature-recruitment trade-offs. This data-driven modeling framework substantially improves our ability to predict consequences of anthropogenic impacts on species-rich tropical forests. I will also outline how we are currently using the model to optimize multi-objective management and support conservation planning in forests in Germany.

Archive: Previous Colloquia