The riverine landscape width of alpine rivers is permanently changing from the source to the outlet due to geomorphology and neighboring land use.
Let's try to get the riverine landscape width along the river course of the alpine river
Inn running through the the federal state of
Tyrol.
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| river Inn through the federal state of Tyrol; backgroud by basemap.at |
Open ingredients:
Workflow:
- extract the river Inn vector line from the river network by v.extract
- calculate sample points e.g. every 10m along the river course by v.fixed.segmentpoints; the distance from source downstream is uploaded automatically to the attribute table
- calculate transect lines right and left of the river e.g. every 10m along the river course by v.transects
- upload the fitting distance from source downstream included in the sample points to the attribute table of the transect lines by v.distance
- extract habitat map types typically for alpine rivers (e.g. alluvial forests, gravel bars, willow thickets, ...) from the habitat mapping vector data by v.extract
- dissolve this extracted polygones by v.dissolve
- clip the transect lines by the dissolved habitat vector map by v.overlay
- upload the vector length of the clipped transect lines to the attribute table by v.to.db
- export the clipped transect lines attribute table as a csv file by v.db.select
- import the csv file into R and do some maths
Some preliminary results:
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| histogram of the riverine landscape width along the alpine river Inn in the federal state of Tyrol |
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| kernel density plot of the riverine landscape width along the alpine river Inn in the federal state of Tyrol |
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| riverine landscape width vs. distance from source downstream (km) |
The riverine landscape width of the alpine river Inn seems to be quite uniform along the course within the federal state of Tyrol, with some increasing width downstream and maybe noisy artefacts.
Let's do some visual checks:
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| transects every 10m along the river course measuring the riverine landscape width; background basemap.at |
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| transects every 10m along the river course measuring the riverine landscape width; background basemap.at |
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| transects every 10m along the river course measuring the riverine landscape width; background basemap.at |
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| transects every 10m along the river course measuring the riverine landscape width; background basemap.at |
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| transects every 10m along the river course measuring the riverine landscape width; background basemap.at |
The visual checks shows more or less the uniformity of the riverine landscape width along the river Inn in this area.
Open data and open software may enable such analysis over a large area, though pre- and postprocessing cleaning steps are needed to reduce noise and artefacts.
