Terrain

Please note: This page is currently being updated.

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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/day	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		Whether this is a water-type terrain. This means constructions that can only be built on land cannot be built on this terrain. In addition, it also counts as a water terrain for overlay calculations. If 1, cells of this type will average the waterlevel, if 0, surface flow will be computed (see Rainfall Overlay)
WATER_DEPTH_M	m	When the new project wizard creates a new project, and this is water-type terrain, this is the maximum depth of that water body.
WATER_EVAPORATION_FACTOR		Factor by which the reference evaporation (see Rainfall Overlay) is multiplied
WATER_MANNING	s/[m1/3]	Roughness of the surface, used in the surface flow computation of the Rainfall Overlay.

Subsurface

In the Tygron Platform there are different subsurface types available. Subsurface terrain data is acquired from FGR. Note: as of Tygron Platform 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	Terrain with a gravel underground layer
Clay	Klei	Terrain with a clay underground layer
Chalk	Krijt	Terrain with a chalk underground layer
Loam	Leem	Terrain with a loam underground layer
Loess	Löss	Terrain with a loess underground layer
Unknown	Onbekend	Default underground if no data is available for your project
Silt	Silt	Terrain with a silt underground layer
Peat	Veen	Terrain with a peat underground layer
Sand	Zand	Terrain with a sand underground layer
Marine clay	Zeeklei	Terrain with a marine clay underground layer

Each underground terrain type has the following attributes:

Attribute	Unit	Description
ANGLE_OF_REPOSE	Degrees	When the new project wizard creates a new project, and this is water-type terrain, this is the maximum steepness of the sloop at the edges of the water (taludhoek).
BUILDABLE		Attribute that determines if a Construction can be built there (0=no, 1=yes)
GROUND_INFILTRATION_MD	meter per day	Limitation in capacity of ground infiltration from the surface into the sub-soil, used in the Rainfall Overlay
PEAT_FRACTION
TOPLAYER_THICKNESS
WATER_STORAGE_PERCENTAGE		Volume of water that can be stored per volume of soil, usually expressed as the saturated minus residual water content properties of soil

Elevation

In the terrain menu, the user can change the elevation-model in the project or import/select an elevation model Geotiff. More info on elevation can be found on the terrain height page