1. General Model Information

Name: ForGro - Forest Growth Model.

Acronym: FORGRO

Main medium: terrestrial
Main subject: forestry, hydrology
Organization level: population, biocoenosis
Type of model: ordinary differential equations
Main application:
Keywords: forestry, growth, water dynamics, carbon balance, nutrient dynamics


Dr. G.M.J. Mohren.
DLO Institute for Forestry and Nature Research (IBN-DLO), BNO, P.O.Box 23, 6700 AA Wageningen, THE NETHERLANDS.
Phone: +31.317.477891
Fax: +31.317.424988
email: g.m.j.mohren@ibn.dlo.nl



ForGro is a process-oriented, deterministic model. The model is a physiologically based carbon-balance model of forest growth. It describes the flow of water, carbon and nutrients in the forest ecosystem. The model can be described as an integrated and closed-system Forest-Soil-Atmosphere model. Processes that are included consist of: photosynthesis and respiration, phenology, hydrology (detailed and partly empirical), nutrient cycling (mechanistic), forest growth (detailed and partly empirical), and forest structure development. ForGro includes hydrological submodels for calculating snow-fall, canopy water dynamics, forest-floor water dynamics and soil water dynamics. Compartments: - Hydrology: Solution of water content from nutrient balance model. Transpiration from Penman-Monteith. - Nutrient uptake: Driven by demand and limited by radial diffusion from the bulk soil to the root. - Soil chemistry: ForGro uses NuCSAM as submodel. - Forest growth: Photosynthesis is driven by light interception. Gross carbon assimilation is summed per leaf layer. Fixed allocation scheme. - Effect relations: Nutrient shortage, and stomatal uptake of SO2 and O3 in foliage reduce photosynthesis. Al effects root growth and nutrient uptake. Direct uptake of NH3.

Purpose of the model: : Aims: validation, and stress assessment.

Model parentage: SUCROS*.

Source of the AbstractCAMASE Register of Agro-ecosystems Models

II. Technical Information

II.1 Executables:

Operating System(s): Mainframe/PC. Contract necessary: Costs: : Nominal. Comments:

II.2 Source-code:

Programming Language(s): Microsoft FORTRAN-77.

II.3 Manuals:

II.4 Data:

III. Mathematical Information

III.1 Mathematics

III.2 Quantities

Rate variables: Main fluxes of water, carbon and nutrients.

State variables: Biomass components.

III.2.1 Input

Tree physiology, site characteristics, stand structure. Input check in model: Partly.

III.2.2 Output

Depends on application.
Basic spatial unit: 1 Ha.
Time interval of simulation: Day.

IV. References

Bartelink, H.H.; Kramer, K.; Mohren, G.M.J. 1997. Applicability of the radiation-use efficiency concept for simulating growth of forest stands. Agricultural-and-Forest-Meteorology.1997, 88: 1-4, 169-179; 33 ref..
Kramer, K. 1996. Phenology and growth of trees in relation to climate change: a modelling study. BOS-Nieuwsletter.1996, 15: 1, 3-11; 9 ref..
Kramer, K.; Mohren, G.M.J.; Smith, T.M. 1994. Sensitivity of FORGRO to climatic change scenarios: a case study on Betula pubescens, Fagus sylvatica and Quercus robur in the Netherlands. Special issue.The application of patch models of vegetation dynamics to global change issues: papers given at the International Geosphere Biosphere Program workshop held at Apeldoorn, Netherlands, 1994. Climatic-Change. 1996, 34: 2, 231-237; 16 ref..
Mohren, G.M.J.; van de Veen J.R..; van Grinsven, H.J.M. 1995. Forest growth in relation to site conditions: application of the model FORGRO to the Solling spruce site.Special issue.Modelling water, carbon and nutrient cycles in forests. Proceedings of a workshop held in Leusden, the Netherlands, 10-14 May 1993. Ecological-Modelling. 1995, 83: 1-2, 173-183; 30 ref..
Kramer, K. 1995. Modelling comparison to evaluate the importance of phenology for the effects of climate change on growth of temperate-zone deciduous trees. Climate-Research.1995, 5: 2, 119-130; 25 ref..
Mohren, G.M.J., H.H. Bartelink, I.T.M. Jorritsma & K. Kramer, 1993. A process-based growth model (ForGro) for analysis of forest dynamics in relation to environmental factors. In: Broekmeyer, M.E.A., W. Vos & H. Koop (Eds.). European Forest Reserves. Proceedings of the European Forest Reserves Workshop, 6-8 May 1992, The Netherlands. Pudoc-DLO, Wageningen, The Netherlands. 273-280
Voet, H. van der; Mohren, G.M.J. et al. 1994. An uncertainty analysis of the process-based growth model FORGRO. Contrasts between biologically-based process models and management-oriented growth and yield models. Papers presented at the IUFRO S4.01 conference, held Wageningen, Netherlands, 2-6 September 1991. Forest-Ecology-and-Management. 1994, 69: 1-3, 157-166; 7 ref..
Mohren, G.M.J., 1987. Simulation of forest growth, applied to douglas fir stands in the Netherlands. PhD, Wageningen, the Netherlands. 184 pp.

V. Further information in the World-Wide-Web

VI. Additional remarks

Parentage: SUCROS
Last review of this document by: T. Gabele: Sep 24 1997
Status of the document:
last modified by Joachim Benz Mon Jul 2 18:31:37 CEST 2007

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