The coupled development of terrain and vegetation : the case of semiarid grasslands

[摘要] (cont.) The soil moisture and vegetation dynamics components of the model are calibrated and compared to observations from a small catchment in southeastern Arizona. The representation of the evolution in time of evapotranspiration, soil moisture and above ground vegetation, and of the spatial distribution of vegetation with the model, are satisfactory. CHILD was used to simulate the evolution of the landscape under bare surface, uniform and stationary vegetation, and dynamic vegetation conditions to evaluate the effects of a dynamic vegetation cover in ten thousand years. In these simulations the emergence of bedrock outcrops that lead to significant runoff, erosion, and the accumulation of sediments and moisture downstream of the bedrock-regolith interface, had the most significant impact in the landscape. Erosion was greatest in the bedrock outcrops, and bands of sediment and moisture accumulation in their downstream ends lead to the development of bands of vegetation that augmented the accumulation of sediment and runoff infiltration.

[发布机构] Massachusetts Institute of Technology