Organic carbon cycling in lakes: exploring the source and sink balance through process modeling

English Abstract:

Understanding of the roles lakes play in the global carbon cycle will be improved through advances in ecosystem models that include major components of the lake carbon cycle. Integrating lake models with catchment models and climate re-analysis products provides opportunities to study how lakes respond to both changes in landscape characteristics and climate variability and to better understand the circumstances controlling the fate of carbon in lakes. In this study, we model organic carbon dynamics in lakes and their catchments, capturing seasonal dynamics of both allochthonous and autochthonous sources of carbon. Model results are compared with major scales of variability in observed organic carbon concentrations to identify shortcomings in model structure reflective of our knowledge gaps in carbon cycling. Uncertainty in predictions, derived from uncertainties in observations and model parameters help identify ecosystem variables that warrant better observations and processes that warrant closer study.