Research
Nonlinear and disequilibrium responses of ecosystems to climatic and land use changes
We are interested in the response dynamics of individual plants, plant communities and entire ecosystems to environmental changes and the underlying processes. We therefore study the ecophysiological and allocation responses of individual plants and plant communities in experiments and combine this with macroecological studies and monitoring in the field to investigate the spatio-temporal response dynamics of plants on various spatial and temporal scales. With this we want the answer an important question: How fast do individual plants, plant communities and entire ecosystems respond to environmental changes happening with different rates of change.
Changing environmental predictability and its effects on plants
The ecological effects of changing mean temperature and precipitation are intensively studied in global change research. This is not true for environmental predictability which seems to be a still neglected but important dimension on global climate change. Decreasing environment predictability fosters disequilibrium conditions and non-linear response dynamics with strong effects on biodiversity and ecosystem functionality. Plants growing in a predictable environment (e.g. predictable temperature regime or water availability) are able to adapt to this high predictability and can increase productivity. Changes in environmental predictability as a syndrome of climate change might therefore have strong effects on ecosystem functionality and productivity in the future. To understand the effects of environmental predictability on plant growth we investigate the plants’ responses to changing environmental conditions in experiments and link this to the climatic conditions in their regions of origin/occurrence.
Effects of pollutants from agriculture, industry, traffic and other sources, on ecosystems
We perform experiments on the effects of pollutants (e.g. heavy metals, plant protection products and chemicals) as well as eutrophying compounds (e.g. ammonia) on single plants, species, plant stands and communities. Besides controlled ecotoxicological experiments in growth chambers and greenhouses to derive dose-response relationships we deal with outdoor studies, in which the accumulation and effects of pollutants are being studied in natural and semi-natural ecosystems. We are using ecophysiological methods as well as classical bioindication.
Actively utilizing plants and plant communities to diminish the effects of global changes, to mitigate climatic extremes and to effectively sequester pollutants
Here we are focusing on single plants traits and ecological services of plant stands and commutities beneficial to design urban landscapes. This covers the introduction of urban green into private and public building (e.g. roof gardens) to mitigate urban heat island effects and to support carbon sequestration. Besides microclimatic advantages and positive effects on biodiversity, green landscape elements can also be used to scavenge air pollutants (gases and particles) as well as airborne biogenic emissions (e.g. germs). In the aquatic and terrestrial environments we are working on constructed wetlands and fast growing woody plants (e.g. phytoremediation by short rotation coppices), which is important in circular economy, the restoration of industrial brownfields and former mining landscapes and which the recycling of grey waters. In all these fields, multiple usage should be strived for, e.g. the use of produced plant biomass for bioenergy or material use (e.g. insulation composites) and the creation of new habitas (e.g. attrative to insects).
Optimization of ecological sampling approaches
Reliable methods to quantify complex (non-linear, disequilibrium) responses of individual organisms, communities or ecosystems is paramount for successful predictions about the functionality and resilience of our ecosystems in the future. We are working on the optimization of ecological sampling in field surveys and experiments to develop sampling protocols capable of capturing such complex responses.