Fun in the sun: exploring effects of photodegradation on carbon cycling in terrestrial ecosystems

AUSTIN, AT

Washington DC

Seminario; Invited Seminar George Washington University; 2017

George Washington University

Plant litter decomposition is an essential process in the first stages of carbon and nutrient turnover in terrestrial ecosystems, and together with soil microbial biomass, provide the principal inputs of carbon for the formation of soil organic matter. Photodegradation (photochemical mineralization of organic matter due to exposure to solar radiation) has recently been identified as a potential mechanism that explains high decomposition rates observed in arid and semi-arid zones. However, the indirect effects of photodegradation on biotic processes responsible for carbon turnover in terrestrial ecosystems have not been elucidated. In this seminar, I will present studies from some new lines of research in from our group in terrestrial ecsosytems of South America that contribute to our understanding of the role of photodegradation as a general control on the decomposition of plant litter. Our results suggests that photodegradation is quantitatively important in determining rates of mass loss and nutrient release through its impacts on biotic decomposition, which has implications for the potential alterations in carbon turnover in terrestrial ecosystems to predicted climate or land-use change.