DAYCENT

Criterion

Explanation

General Description

Daily time-step version of the CENTURY biogeochemical model (version 4.0) used to simulate daily carbon and nitrogen gas fluxes between atmosphere, soil and vegetation for grassland, agricultural crop, forest and savanna systems.

Model Domain

General

Developer

Colorado State University, Natural Resources Ecology Lab.

Hardware computing requirements

Minimum requirements: 512K RAM, 220 KB to 2 MB disk capacity. Graphics adapter (CGA, EGA, VGA, or Hercules monographic) is recommended.

Code language

FORTRAN

Original application

Original model developed for simulation of carbon, nitrogen, phosphorus and sulfur dynamics in cultivated and uncultivated grassland soils (Parton et al., 1988).

Public/proprietary and cost

Model is publicly available, no associated cost for usage. The source code "DailyDayCent" is protected by a United States copyright to Colorado State University, all rights reserved; distribution and modification of this source code requires that permission is obtained from developer.

Physically or empirically based

Model physically based on established biogeochemical relationships.

Mathematical methods used

Model consist of various sub-models: soil water content and temperature by layer, net primary production allocation and plant production, decomposition (litter, soil organic matter), nutrient mineralization, nitrogen gas emissions due to nitrification and denitrification, and methane oxidation in non-saturated soils. Ecosystem processes generally expressed as algorithms or functions details can be found in Del Grosso et al., 2003; Parton et al., 1998; Alister et al., 1993.

Input data requirements

Daily maximum/minimum air temperature, daily precipitation, soil properties (bulk density, soil texture class, initial soil carbon, nitrogen, phosphorous and sulfur content), daily land management and vegetation data (vegetation type, cultivation and planting timeline, nutrient amendments, harvest practice, senescence, root type and distribution, vegetation productivity, C:N ratios, root to shoot ratios, lignin content), irrigation application, wet and dry nitrogen deposition and location coordinates.
Meteorological, soil, land management and some vegetation data can be obtained from public databases, more specialized vegetation data can be obtained from pier reviewed literature.

Outputs

Daily gas flux (N₂O, NO_x, N₂, CO₂) soil organic carbon and nitrogen, nutrient cycling, net primary productivity, daily plant production, H₂O and NO₃ leaching and other ecosystem parameters. Output can be viewed in plot format provided with model application file.

Pre-processing and post-processing tools

Model application file.

Representation of uncertainty

Uncertainty not directly incorporated into model framework. Some evaluation of uncertainty in model predictions have been made using inverse modeling and comparison to observed data (Necpálová et al., 2015; Del Grosso et al., 2008; Del Grosso et al., 2005; Parton et al., 1998).

Prevalence

Model very commonly applied by academic institutes, less widely applied by government entities. Applications commonly include, but are not limited to, gas emission estimates, biomass production and emission mitigation for agricultural, tropical, pasture and deserts systems.

Ease of use for public entities

Easy to Moderate: no formal training required, user guides available. No specialized software needed.

Ease of obtaining information and availability of technical support

No commercial help desk available. User guide available at https://www2.nrel.colostate.edu/projects/daycent-downloads.html, user manual for CENTURY model available at http://www.nrel.colostate.edu/projects/century/century-downloads.php. Model workshop information available at https://www.nrel.colostate.edu/education/century-and-daycent-model-training-workshops/. Limited user support available through email (century@colostate.edu or century@nrel.colostate.edu).

Model and Source code availability

CENTURY model version 4.0 available at https://www2.nrel.colostate.edu/projects/daycent-downloads.html. More current versions of CENTURY model, DAYCENT model and source code "DailyDayCent" is available upon request from century@colostate.edu.

Status of model development

Model available to users via internet or upon request.

Challenges for integration

Integration challenges not clear. Model able to simulate output from various timesteps.