topic Re: Creating a maximum cost pathway/ corridor in ArcGIS Spatial Analyst Questions

Creating a maximum cost pathway/ corridor

fahiemadaniels — Thu, 22 Jan 2015 08:36:58 GMT

I am hoping someone can advise me on how to go about doing the following analysis or which tools to use. I have a 150km wide grid made up 30m pixel cells with values ranging from 0 to 11. I need to run an analysis to select a 100km wide corridor in the 150km corrdier for where thecells in the corridor add up to the maximum value. the 150km wide corridor is 1000km long

Re: Creating a maximum cost pathway/ corridor

DanPatterson_Retired — Thu, 22 Jan 2015 09:18:34 GMT

and you have ruled out reversing the costs associated with your classes? in that way, was a deterrent will now serve as an attractant

Re: Creating a maximum cost pathway/ corridor

fahiemadaniels — Thu, 22 Jan 2015 09:30:26 GMT

Thanks Dan Patterson‌ I have set it up and inverted the numbers just incase. So do I just run a cost distance then? and I am unsure as to how to specify that the corridor created must be 100km wide though. Any ideas/ suggestions would be highly appreciated.

Re: Creating a maximum cost pathway/ corridor

DanPatterson_Retired — Thu, 22 Jan 2015 09:54:33 GMT

In cost analysis, you ascribe costs to landscape features, the lower the cost, the easier it is to traverse a piece of terrain (for example). By changing the order of the costs, things that were attractants now become deterrents...then do your regular procedure of doing the cost distance.

I should point out at this junction that you have used a linear scale meaning that there is little separation between the various classes. The path you will get differ drastically when you use non-linear scales since the ultimate goal is to minimize the traverse cost ... ultimately to a destination if you are extending this to an ultimate path.

For example in stead of

1, 2, 3, 4, 5, 6, 7, 8, 9

you used

1,2, 30, 40, 500, 6000, 7000, 8000,9000

I would venture that the likelihood of any segment of a path traversing the 4th or above classes would be minimal at best.

A cost, cost distance and ultimately a cost path analysis is purely subjective in the sense that I can generate any desired path from an origin to a destination simply by changing the order and/or cost values associated with landscape features.

should you wish finer, control, generate a slope map and aspect map, reclassify and add those to your cost surface generating a new cost surface...

So in summary....I can generate any minimal/maximal cost path desired simply by altering the factors to include in the 'cost' for a location, and the values I assign to the classes used in the cost.

so this becomes a "where do you want the path to go" style question

Re: Creating a maximum cost pathway/ corridor

XanderBakker — Thu, 22 Jan 2015 12:09:08 GMT

To create a corridor that is 100km wide is a little difficult when you use costs that are different than the value 1. You may want to look into the Corridor tool in Spatial Analyst: ArcGIS Help (10.2, 10.2.1, and 10.2.2)

To create a corridor with a with of 100 km you could use the Buffer tool (when you have you route converted to line) or the Euclidean Distance tool for raster input.