For improvement in understanding eco-hydrological processes in mire

Various anthropogenic stressors have caused mire degradation in subarctic northern Japan, such as drying and the invasion of an alder-dominant shrub forest. The Japanese government recently started a nature conservation project to restore a formerly meandering river in order to prevent invasive forest species and to rehabilitate the original mire ecosystem. In this study, the process-based National Integrated Catchment-based Eco-hydrology (NICE) model is further developed to improve accuracy in evaluation of nonlinear interactions and feedback of hydro-geomorphology and vegetation dynamics in the ecosystem. The simulated results clarify the impact of groundwater level change, sediment deposition, and nutrient availability on the complex alder invasion after refining the model to include newly-developed down-scaling and feedback processes. The model also shows the interaction between groundwater and inundated flow and its effect on vegetation change, which sheds light on two conflicting conceptualizations of peatland hydrology. This integrated system links the hydrological approach to the ecological one implicitly in the model, and throws some light on the refinement of tipping-point early warning systems for sustainable development and the improvement in boundless biogeochemical cycles along terrestrial-aquatic continuum for global environmental change.