Landuse in Dry Tropical Savannas
Savanna - Landscape and Regional Ecosystem Model
The spatial structure
The model has a three scaled hierachical spatial structure.
It is spatially explicit at the landscape scale. In other words, it is sensitive
to spatial location at this scale.Grid cells cover landscapes or regional-scale
ecosystems. Grid-cell is scaled to the spatial extent of the simulated ecosystem.
It is spatially inexplicit at the subarea or patch scales. Within grid-cells the
model is sensitive to the proportions of grid cell covered with subareas which
correspond to fixed distributions of the physical factors like topography and
soils. Within subareas the model simulates vegetation patches or "facets".
These are defined by covers of herbaciouous plants, shrubs and trees. Therefore
facet cover is a dynamic outcome of vegetation growth and mortality. Facet
locations are not modeled, only frations of subareas that are covered by the facets.
- Landscape scale
Within subareas and facets, plant growth and soil and water budgets are modeled.
The results are scaled up by multiplying by the fraction of the grid cell covered
by each patch type (herbaciouous plants, shrubs and trees).
Savanna is made of several interacting
sub-models, these are;
- Soil water sub-model
- Light sub-model
- Net primary production sub-model
- Plant population dynamics sub-models
- Plant fire responses
- Herbivory sub-model
- Ungulate population dynamics sub-model
- Ungulate distribution dynamics sub-model
- Predator sub-model
- Snow sub-model
The snow sub-model is not relevant for this particular case study.