Dániel TájmelDoctoral Student
Terrestrial biogeochemical cycles are regulated by soil microorganisms. The microbial carbon release due to respiration and carbon sequestration through microbial growth determine whether soils become sources or sinks for carbon. Temperature is one of the most important environmental factors controlling both microbial growth and respiration. Therefore, to understand the influence of temperature on microbial processes is crucial since the altered temperature can influence the activity and adaptation of microbial communities.
The main focus of my PhD projects is to understand the microbial temperature dependences in soil, if and how they will feedback to climate change.I study how soil warming affect the temperature relationships for microbial growth and respiration in different biomes across seasons.The link between microbial temperature relationships and the climate is assessed by using the relationship between the environmental temperature and indices including the minimum (Tmin), optimum (Topt) and maximum (Tmax) temperature for microbial growth andfor respiration. To estimate the Tmin, Topt and Tmax ,we use models including the square root equation, the Ratkowsky. Furthermore, I would like to understand what is theinfluenceof warming onthe microbial community structure, therefore, linking microbial temperature relationships to differences in the community. By incorporating the determined relationships between environmental temperature and microbial growth and respiration into large scale ecosystem models, we can get a better understanding of the influence of microbial adaptation to warmer climate on the C-exchange between soils and atmosphere. .
The study I use includes environmental surveys, field experiments as well as laboratory experiments. In the laboratory, I use different methods, such as radioisotope tracer based methods to measure microbial (bacterial and fungal) growth and biomass markers.