/DALEC-Grass

DALEC-Grass : A biogeochemical model of carbon dynamics in managed grassland ecosystems

Primary LanguageFortranGNU General Public License v3.0GPL-3.0

DALEC-GRASS

This fortran code is a development of the Data Assimilation Linked Ecosystem Carbon (DALEC) model that simulates carbon (C) dynamics in managed grassland ecosystems. DALEC-Grass requires 10 input variables and uses 33 parameters to estimate various C pools and fluxes. Model inputs, parameters, pools and fluxes are described in the first lines of the code. The Aggregated Canopy Model (ACM) lies at the core of DALEC and is used to estimate daily Gross Primary Production (GPP). At each timestep, DALEC allocates the estimated Net Primary Production (NPP) to the different plant tissues/pools (root, stem, leaf). DALEC-Grass can be integrated into a model-data fusion (MDF) framework to constrain the dynamics of the C pools and fluxes using observed data.

alt text Figure: Schematic description of the DALEC-Grass model. DALEC-Grass simulates the dynamics of 5 C pools (C) : leaf, stem, roots, litter and SOC. C is allocated to the 5 C pools via NPP allocation (A) and litter production (L). Vegetation removals (VR) can occur due to grazing or cutting. DALEC-Grass determines whether a vegetation removal is caused by grazing, cutting or neither. When cutting is simulated (VRc>0) cut biomass (Bc) is removed from the ecosystem. When grazing is simulated (VRg>0) 32% of grazed biomass (Bg) is converted to manure, 54% of grazed biomass (Bg) is converted to animal respiration (aCO2) and 4% of grazed biomass (Bg) is converted to methane (aCH4). Dotted lines show outward fluxes of C. Solid lines show internal and inward fluxes of C