Jim Kiniry (USDA-ARS)


Model category FSPM, CSM
Plant part Shoot
Scale Whole_plant
Licence freeware
Operating system Windows
Programming language Fortran
Format of model inputs and outputs NA
Species studied Switchgrass, Maize, Sorghum, Sunflower
Execution environment Stand-alone application

Scientific article

A general, process-oriented model for two competing plant species
Kiniry,J.R.,Williams,Gassman,P.W.,and Debaeke,P.
Transactions of the American Society of Agricultural Engineers, 1992 View paper

Model description

The ALMANAC model simulates crop growth, competition, light interception by leaves, biomass accumulation, partitioning of biomass into grain, water use, nutrient uptake, and growth constraints such as water, temperature, and nutrient stress. Plant development is temperature driven, with duration of growth stages dependent on degree days. Each plant species has a defined base temperature and optimum temperature. The simulation of competition for light is based on Beer's law, allowing a different extinction coefficient (k) for each species. Light is partitioned between species based on k-values, leaf area index (LAI) and plant heights. LAI, light interception with Beer's law, and potential daily biomass increase with a species-specific value of radiation use efficiency (RUE). The model simulates competition for water and nutrients based on each species' current rooting zone and demand by each species. The daily increases in and biomass are reduced when plant available water in the current rooting depth is insufficient to meet potential evapotranspiration. Total biomass is simulated with radiation use efficiency and grain yield with a harvest index approach, sensitive to water stress. Grain yield is simulated based on harvest index (HI), which is the grain yield as a fraction of the total aboveground dry matter at maturity.

Some case studies

Some recent studies using ALMANAC:

- Meki, M.N. and Kiniry, J.R. A Dynamic Tool - Resource assessment framework for dependable feedstock supply to produce advanced biofuels in Hawaii. 2013.

- Lowry, D.B., Behrman, K.D., Grabowski, P., Morris, G.P., Kiniry, J.R., and Juenger, T.E. Adaptations between ecotypes and along environmental gradients in Panicum virgatum. The American Naturalist 183:682-692. 2014.

- MacDonald, J.D., Luke, S.L., Kiniry, J., and Putz, G. Evaluating the role of shrub, grass and forb growth after harvest in forested catchment water balance using SWAT coupled with the ALMANAC model. In Abbaspour, K. and Srinivasan, R. (eds). Texas Water Resources Institute, College Station, TX. Proceedings of the 4th International SWAT Conference, UNESCO-IHE, Delft, The Netherlands, July 2-6. 12 p. 2007. (In Press)