Dominik Merges







Dominik Merges

Ph.D. student


My research interests focus on how abiotic and biotic interactions can limit or facilitate plant regeneration. Abiotic conditions like temperature have long been the main focus in ecosystem research, but in recent years the importance of biotic factors like seed dispersal by animals or interactions between plants and soil communities have become increasingly recognised. In order to fully understand plant regeneration, and thus species distribution, it is important that a multi-trophic approach is taken, taking both abiotic and biotic factors, and the interaction between the two in account. I make use of elevational gradients in order to investigate the effects of biotic and abiotic factors on plant regeneration. As elevational gradients have a wide range of conditions over a narrow area (several hundred of m a.s.l.) they provide a great natural system for studying effects of biotic and abiotic factors on seedling recruitment.

The European Alps provide an especially useful elevational gradient to investigate the factors effecting plant regeneration. Here a mutualistic relationship exists between the Swiss stone pine (Pinus cembra) and the Spotted nutcracker (Nucifraga caryocatactes). The pine seeds are dispersed by the nutcrackers along temperature gradients in alpine treeline ecotone, exposing them to harsh conditions. It has been hypothesized that interactions between Swiss stone pine and mutualistic fungi facilitate seedling recruitment in the extreme habitat at the alpine treeline. This system is a good opportunity for us to investigate the effects of climatic (abiotic) factors as well as variety of biotic factors e.g. interactions with birds and fungi on plant regeneration.

By combining a variety of different methods such as field observations and experiments, as well as next-generation sequencing (NGS) of soil communities, I try to answer how the pine regeneration is either limited or facilitated in its environmental space.

We can make use of this study to understand how mutualistic relationships effect plant regeneration and how these factors alter across the elevational/climatic gradient. This is particularly important in the light of ongoing global climate change, which could drive apart the ranges of interdependent species with a mismatch of future habitats potentially leading to extinction.



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