Doctoral candidate
Fitness effects of invasive plants on pollinators
Tel: +49 (0)711 / 459-23505
e-mail: d.becker@uni-hohenheim.de
Research project
As part of my PhD thesis (2024-2027), I am investigating the fitness consequences of trait-mediated interactions between the invasive Indian balsam (Impatiens glandulifera), native plants and their pollinators. The aim of my research is to understand how Indian balsam is integrated into existing pollinator networks, how it alters them and what consequences this has for native pollinators, especially wild bees.
My project will be carried out in landscapes along streams and wet meadows that are invaded by Indian balsam. In these invaded areas as well as in non-invaded control areas, the interactions between pollinators and plants will be observed in 2024, the pollinators will be netted and subsequently identified, and plant-pollinator networks will be established for each landscape. In the following year, 2025, mason bees (Osmia bicornis) and bumblebees (Bombus terrestris) will be released in these landscapes and their fitness in terms of reproductive success will be measured over the course of a year. In addition, similar experiments are being carried out on the experimental farm Heidfeldhof of the University of Hohenheim in a more controlled environment with mesocosms. The aim is to gain a mechanistic understanding of how the matching of functional traits of plants and pollinators influences the interactions between I. glandulifera, native plants and their pollinators. In particular, it will be investigated to what extent different proboscis lengths of wild bees and the flowering depth of different native plants and Indian balsam interact. In addition, the effects on the fitness of the bees through reproductive success and of the plants through their seed production will be investigated.
The main questions are:
At the end of the doctoral thesis (2026-2027), recommendations for action will be developed.
Curriculum vitae
I studied Agricultural Biology at the University of Hohenheim and quickly realised that I was particularly interested in ecosystem processes and functions. My bachelor thesis in the Land4Biodiversity project focussed on how the complexity of agricultural landscapes affects the diversity of insect pollinators, especially wild bees. Through this project, I acquired skills in pollinator monitoring and insect taxonomic identification. During my master's studies in the MSc Landscape Ecology, I deepened my knowledge in entomology and field ecology. For my master's thesis, I travelled to the Caribbean lowland rainforests of Costa Rica to investigate the effects of rainforest fragmentation on the resilience of trophic interaction networks between frugivorous birds and fruit-bearing trees.
