Progress in Ecohydrological Model Development for Trait-Based Watershed Modeling
Authors
Jinyun Tang* (jinyuntang@lbl.gov), Sergi Molins, Zexuan Xu, Andrew Graus, Zelalem Mekonnen, Lijing Wang, Chuyang Liu, Eoin Brodie (elbrodie@lbl.gov)
Institutions
Lawrence Berkeley National Laboratory, Berkeley, CA
URLs
Abstract
High-fidelity mechanistic models play a crucial role in comprehending the interplay of ecosystem hydrologic and biogeochemical cycles, and traits that govern the retention and release of elements in mountainous watersheds. To accurately represent the coupling between hydrological, ecological, biogeochemical, and land-surface processes, adaptive-resolution physics-based models are necessary to capture trait interactions and watershed functions. While various modeling codes capture some aspects to quantify trait interactions and watershed function, none can fully address the entire problem.
The project aims to couple the Advanced Terrestrial Simulator (ATS) with the plant-soil-microbe interactions code EcoSIM. In the proposed coupling, ATS provides water balance and solute transport, while EcoSIM simulates plant water uptake, surface energy balance, microbial dynamics and ecosystem biogeochemistry. The coupling framework follows the established Alquimia library, which was successfully used to add geochemical capabilities to ATS. Specific issues related to ecohydrological processes and EcoSIM require large-volume data transfer and a soil column-based coupling rather than a cell-by-cell one.
Here, researchers present results from baseline hydrological simulations for the East River watershed, CO. Researchers also describe EcoSIM, which is newly developed from its predecessor code ecosys, and provide an update on the ATS-EcoSIM coupling. This update discusses how these combined capabilities will enable researchers to quantify 3D landscape trait interactions and watershed function in the Watershed Function Science Focus Area. East River hydrological simulations show how high-resolution models, parameterized using spatially heterogeneous datasets, can provide a quantitative evaluation of the connection between traits and function, and uncover limitations in the current simplified treatment of land surface processes. Example, EcoSIM simulations demonstrate its capability to simulate typical ecosystems, including forests, grasslands, and wetlands. Test simulations for ATS-EcoSIM demonstrate the development approach, which involves implementing and testing processes separately, starting with surface energy and water, then snow physics, and continuing with plant and microbe dynamics.