Terrain
(In Dutch)
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 any features built upon it, which are known as constructions.
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 |
---|---|---|
Breakwater | Golfbreker | A construction designed to protect the coastline from wave action. |
Concrete | Beton | Commonly found in urban and industrial areas. |
Dunes | Duinen | A naturally occurring landscape feature forming the division between the beach and the hinterland. |
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. |
Levee | Dijk | A construction usually built between a water body and low-lying land (polder) offering protection from flooding. |
Sand | Zand | Area largely consisting of sandy sediment. |
Sea | Zee | Water that is part of a sea or ocean. |
Waterbody | Watervlakte | A water body which is often not part of a 'managed' water system. |
Waterway | Waterloop | A waterway which is often part of a 'managed' water system |
Each surface terrain type contains the following attributes: Template:Terrain attributes table start
BUILDABLE boolean Both Whether it is permitted to place Buildings here GROUND_INFILTRATION_MD m/day Surface 0 to 10 The speed at which water can flow vertically from the surface to the unsaturated zone. GROUND_INFILTRATION_MD m/day Ground 0 to 10 The speed at which water can flow vertically from the surface to the unsaturated zone. HEAT_EFFECT °C Surface Measure of impact on the Heat Overlay LIVABILITY_EFFECT Surface Measure of impact on the Livability Overlay. Polder water (Terrain Attribute) Safety (Terrain Attribute) TERRAIN_MIX Surface TEXTURE TYPE Integer Surface 0 to 2 Value used to select the terrain blend color. WATER nominal Surface Whether this Terrain Type represents a form of water (and what type). WATER_DEPTH_M m Surface The default depth of this water Terrain Type, relative to the surrounding elevation. WATER_EVAPORATION_FACTOR factor Surface How fast this terrain can evaporate water from the ground. The weather's evaporation speed is multiplied by this factor to determine the rate of evaporation. WATER_MANNING s/(m1/3) Surface The Gauckler–Manning coefficient of the terrain, which is a measure of surface roughness. Used in the surface flow computation of the Water Overlay. Template:Table end
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: Template:Terrain attributes table start
ANGLE_OF_REPOSE angle (0-90°) Ground The different subsurface types each attain a value for the maximum slope (Dutch: talud). This value is used for creating the water edge steepness and indirect for the water depth. BUILDABLE boolean Both Whether it is permitted to place Buildings here GROUND_INFILTRATION_MD m/day Surface 0 to 10 The speed at which water can flow vertically from the surface to the unsaturated zone. GROUND_INFILTRATION_MD m/day Ground 0 to 10 The speed at which water can flow vertically from the surface to the unsaturated zone. PEAT_FRACTION fraction Underground The fraction of the subsurface which will be considered to be peat by the Subsidence Overlay. TOPLAYER_THICKNESS m Ground The depth of the clay soil layer, as considered by the Subsidence Overlay. WATER_STORAGE_PERCENTAGE fraction (m3/m3) Ground The percentage (as a fraction) of the ground layer volume which can be filled with water. A lower percentage means the ground layer will be able to store less water, and the saturated zone will rise higher with the same amount of water in the ground layer. Template:Table end
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.