Terrain
What is meant by Terrain?
The Tygron Platform uses the term terrain to describe the composition of the surface, subsurface and their elevation in a project. This does not include anything built upon it, which falls under the term buildings. Within the Editor the terrain in a project can be accessed from the ribbon tab Current Situation → Terrain.
Surface
The Tygron Platform differentiates between various types of terrain. Each terrain type has its own predefined attributes that may have an effect on various indicators and overlays, such as green, livability and rainfall flooding. A description of all available terrain types is listed in the table below.
| EN | NL | Description |
|---|---|---|
| Concrete | Beton | Commonly found in urban and industrial areas. |
| River water | Boezemwater | Larger water body, navigable for (small) boats. |
| Dike / Levee | Dijk | A construction usually built between a water body and low-lying land (polder) offering protection from flooding. |
| Dunes | Duinen | A naturally occurring landscape feature forming the division between the beach and the hinterland. |
| Breakwater | Golfbreker | A construction designed to protect the coastline from wave action. |
| Grassland | Grasland | Area dominated by grass vegetation. |
| Open land | Open land | The default terrain type for land surface. If an empty world is generated, this type will cover the entire map. |
| Water | Water | Small water body |
| Sand | Zand | Area largely consisting of sandy sediment. |
Each surface terrain type contains the following attributes:
| Attribute | Unit | Description |
|---|---|---|
| BUILDABLE | Indication whether a terrain can be built upon or not. | |
| GROUND_INFILTRATION_MD | m/d | Infiltration capacity of the surface soil into the subsoil. This attribute is used in calculations of the Rainfall Overlay. |
| HEAT_EFFECT | °C | Measure of impact on the heat stress overlay. |
| LIVABILITY_EFFECT | Measure of impact on the livability overlay. | |
| POLDER_WATER | ||
| SAFETY | ||
| TERRAIN_MIX | ||
| TEXTURE_TYPE | ||
| WATER | Many constructions can only be built upon land, hence cannot occur on this terrain type. Water terrains play an important part in the calculations by the Water Module. | |
| WATER_DEPTH_M | m | Whenever a new project is created by going through the new project wizard, all water terrains will attain this value for the maximum depth. |
| WATER_EVAPORATION_FACTOR | Multiplication factor of the reference evaporation (see Rainfall Overlay). | |
| WATER_MANNING | s/m1/3 | Measure of surface roughness, used in the surface flow computation of the Water Module. |
Subsurface
The Tygron Platform differentiates between various types of subsurface terrain types. Subsurface terrain data was originally acquired from FGR, however, as of version 2019.0.0 this has become BRO. The Subsurface Overlay shows the different soil types composing the subsurface, each having distinctive predefined attributes. The table below shows a division into the different terrain categories, which, in turn, have their own subdivisions into multiple subsurface soil types.
| EN | NL | Description |
|---|---|---|
| Gravel | Grind | |
| Clay | Klei | |
| Chalk | Krijt | |
| Loam | Leem | |
| Loess | Löss | |
| Unknown | Onbekend | Default, if no subsurface data is available. |
| Silt | Silt | |
| Peat | Veen | |
| Sand | Zand | |
| Marine clay | Zeeklei |
Each subsurface terrain type contains the following attributes:
| Attribute | Unit | Description |
|---|---|---|
| ANGLE_OF_REPOSE | ° | Whenever a new project is created by going through the new project wizard, the edges of all water terrains will attain this value for the maximum slope (Dutch: talud). |
| BUILDABLE | Attribute determining whether or not the subsurface tolerates the construction of new buildings (0 = no, 1 = yes). | |
| GROUND_INFILTRATION_MD | m/d | Infiltration capacity of the surface soil into the subsoil. This attribute is used in calculations of the Rainfall Overlay. |
| PEAT_FRACTION | ||
| TOPLAYER_THICKNESS | ||
| WATER_STORAGE_PERCENTAGE | Fraction of the volume of water that can be stored per volume of soil, usually expressed as the saturated minus residual water-content properties of the soil. |
Elevation
From the Terrain tab, the user can choose to manually change the current surface elevation model in the project, or to import one in the form of a GeoTIFF file. More information regarding the elevation model can be found on the terrain height page.