¹Complex Systems Science Lab, Department of Landscape Architecture and Rural Systems Engineering, Seoul National University, Seoul 151-921, Korea

²National Center for Agro-Meteorology, Seoul National University, Seoul 151-744, Korea

The biogeochemical processes in rice paddies can be viewed as a network of processes of a wide range of scales involving various feedbacks and self-organization. Finding such networks of feedback loops for agricultural ecosystems in Asia is of great value and concern. However, the traditional correlation-based analysis cannot distinguish such complex processes with detailed information on direction and strength of the couplings between the variables. We examine the dependence between a series of variables (including CH₄ and CO₂ fluxes) measured at the eddy flux towers during the growing season of 2011 in Korean rice paddies by quantifying the information flow between the different variables along with the associated time lag. The objective of our study is to test the applicability of information theory to biogeochemical systems with the datasets obtained under different environmental conditions.