| The quantification of interspecific variation in plant functional traits is an important tool helping us to understand and predict ecosystem functioning and ecosystem responses to environmental change. However, investigations of plant functional traits in recent decades have been biased almost exclusively towards vascular plants. Very little is known about the role and applicability of functional traits in non-vascular cryptogams. Yet, cryptogams are paramount determinants of ecosystem functioning in many biomes, particularly in cold biomes, where they contribute substantially to aboveground biomass and control soil temperatures, hydrology, and substrate pH and nutrient availability. This fellowship proposal forms an extension of the cryptogam functional trait research of our current NWO funded programme entitled ?Scaling up from plant traits to vegetation change in cold biomes: common patterns in the European Subarctic and the Caucasus Mountains?? we shall specifically address the following questions: (1) whether soil acidification capacities and temperature insulation capacities vary between cryptogam species and whether these traits can be predicted from other traits, such as tissue pH, tissue chemistry and cell wall micro-structure (for cryptogam acidification capacity) and water retention capacity, shoot archititecture and cushion structure and density (for cryptogam insulation capacity). Subsequently, we want to (2) analyse the role of acidification and insulation capacity of cryptogams for ecosystem functioning in terms of changes in soil properties, available nutrients, mineralization and nitrification rates. As neither acidification nor insulation capacity of cryptogam species has been systematically studied yet, an important part of the work will be the development of new protocols for these measurements. The intended experimental work will comprise a combination of standardised lab screening tests (e.g. tissue pH), standardised multi-species screening under semi-natural outdoor conditions (e.g. temperature insulation capacity, acidifying potential) and in situ measurements in target ecosystems. |
