The hydrological cycles are intimately linked to the carbon and nitrogen cycles in the vegetated areas. This study aims to improve our understanding of how soil hydrological processes (such as hydraulic redistribution, roots water uptake, and frozen soil permeability) regulate biosphere–atmosphere interactions and ecosystem dynamics in boreal forest regions in North America.

This study uses the latest versions of the state-of-the-art Community Land Model (CLM4) that includes three different levels of details representing biosphere–atmosphere exchanges (i.e., CLM4 with satellite phenology – CLM4SP, CLM4 with the explicit carbon and nitrogen balances – CLM4CN, and CLM4CN integrated with a global dynamic vegetation model – CLM4CNDV). A series of numerical experiments are carried out with these versions of CLM4 and their progressive augments of soil hydrological processes in conjunction with NASA datasets, such as global land data assimilation system (GLDAS) meteorological forcing and surface variables, MODIS-derived products of leaf area, gross primary productivity (GPP), and leaf duration.