Example - Mapping extent of an invasive species
Scenario
An invasive species has been introduced into the catchment at a known location. This species is capable of moving in an upstream direction a maximum of 1km per week. Where could it have reached in 1 month?
The following guide is using a fictitious location and species...
Workflow
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Step |
Processing Task |
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1 |
You have prepared your river network and created a snapped point location where the invasive species was introduced into the river.
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2 |
You could run the Create upstream nearby network tool 4 times incrementing the network length by 1000m to see the expansion of the invasive species over a month but such a task could be easily automated in model builder.
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3 |
The create upstream nearby network was completed as shown below, note distance is an inline variable substitution from the FOR iterator. Output is also being dissolved into a multi-part feature. Output is written to the Sites Geodatabase.
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4 |
Although you never set the output name the tool does not overwrite an existing output it simply tags a numeric suffix. You can then add these layers back to the map and symbolise as needed.
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You could continue model logic and include downstream nearby network to see where the species could potentially invade in a downstream direction. With the nearby network extracted as a spatial object you could involve it in further spatial analysis such as intersecting it with riparian data. |
