Acidity and nutrient constraints on organic matter balance and nitrogen saturation in forest soils

Principal investigator: Mgr. Filip Oulehle, Ph.D.
(Co)investigator from the Department: Karolina Tahovská
Duration: 2014 - 2016

Project goals: 
1) assessment of the shift in the relative balance of soil N and C accumulation, versus losses in either organic or inorganic forms, 2) description of the change in internal soil processes and decomposer composition and its link to the change in soil chemistry, 3) biogeochemical modelling

Project description: 
Nitrogen (N) and sulphur (S) deposition are important drivers of the terrestrial carbon (C) and N cycling. In the past 25 years deposition of S has decreased by >80%, whereas reduction in N deposition was much smaller. It is thus possible that recent measurements of C and N fluxes might not be representative of systems in long-term balance with climatic conditions. A set of replicated acidity/N availability experiments in beech and spruce forests will be undertaken in an area of formerly high S/N deposition to understand the combined effects of S and N deposition on C and N cycling in forest soils. In each experiment, we will measure the effects of soil alteration on: A) losses of C and N in gaseous and dissolved forms, B) soil microbial community composition and C) key ecosystem processes, such as the transformation of C and N between organic and inorganic forms, using a combination of cutting edge isotopic tracing and molecular techniques, enzyme measurements and ecosystem modelling.