Selected publications

The authors conducted innovative in-situ monitoring of stable water isotopes in plant xylem water over an entire growing period including a major drought to assess how urban trees react to changing water supply. They also detected fractionation in plant water. Urban trees rely on deep water supply and internal storage during drought.

Quantifying the sources for plant water uptake and their dynamics is still a challenge in ecohydrology. As isotopic analyses becomes more widespread, common methodological frameworks are required. This paper provides guidelines for (1) sampling soil and plant material for isotopic analysis, (2) methods for laboratory or in situ water extraction, and (3) measurements of isotopic composition.

The study investigated the effects of the herbicide metolachlor on host-parasite interactions, using the host-parasite system of the toxigenic cyanobacterium Planktothrix agardhii and its chytrid parasite Rhizophydium megarrhizum. Metolachlor promoted cyanobacteria growth and caused multi and transgenerational detrimental effects on parasite fitness. However, these effects are reversible.

To investigate how dissolved organic matter is degraded in soil and aquatic ecosystems by microorganisms, the authors analyzed its molecular diversity in relation to microbial communities and physicochemical conditions. Changes in DOM composition were consistent across different environments – as degradation progressed, DOM became dominated by universal, hard-to-break-down compounds. 

The authors investigated the variability of planktonic bacteria and benthic diatoms coupled with insights from hydrochemistry and stable water isotopes across four urban streams in Berlin. DNA metabarcoding results shows substantial spatio-temporal variability across urban streams in terms of microbial diversity and richness, with clear links to abiotic factors and nutrient concentrations.

Increasing droughts require a better understanding of connectivity and groundwater-surface water interactions. The authors used a multi-proxy approach of isotope tracers, groundwater data and geophysics to develop a conceptual model of landscape connectivity and groundwater recharge and assessed the effects of land use and catchment properties of groundwater systems sensitive to climate change.

Since the simulation of evaporation and vegetation response to moisture deficits is subject to uncertainties, the authors assessed the benefits of integrating satellite-based land surface temperature data into ecohydrological modelling. They show that even few satellite images can reduce uncertainties of vegetation parameters and improve simulated spatial patterns of land surface temperature.

This study aimed to unravel the heterogenous spatio-temporal patterns of hydrological processes in a riparian wetland over 2 years. The work provided insights into ecohydrological wetland functioning, but also revealed potential equifinality in process-based models even with abundant data for calibration, and solutions based on the integration of water isotopes and soft data into modelling.