how can measure general slope, aspect and height of polygons?

[mortazapirouz]

Hi everybody
I have a  polygon shp file from 300 landslides and  I need to have some information  for this landslides
1- general slope of landslide`s polygon (not cell by cell) 
2- general aspect of polygons
3- average height and max and min height of polygons
I need all this data for each polygon one by one.
I know which I have to do this in several steps but I dont know how? please tell me how can I do this. I searched a lot but ,no solution.
Thanks

[DanPatterson_Retired]

Did you rule out some of the information that can be obtained from ZonalStatisticsAsTable?
http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//009z000000w8000000.htm

[JeffreyEvans]

I am not sure exactly what you mean by "general slope and aspect" but a Zonal function will return a specified statistic (min, max, mean, median, stdv, etc...). I should point out that if you are after the mean aspect, this is quite erroneous because aspect is a circular variable. If you want mean aspect for an area you should transform aspect into a linear measure.

[DanPatterson_Retired]

Good point ... a quick Google search using "circular statistics" will provide numerous links on how to derive 'circular' or 'directional' statistical parameters from input data.

[Luke_Pinner]

For "general slope and aspect" I'd generate an elevation trend surface from your DEM (masked to your polygon):

• Clip and mask your DEM to the polygon then convert the masked DEM to points, or...


• Create Random Points constrained by your landslide polygon which you can use to sample the elevation values.

Then

• Generate the elevation trend surface from those points and then calculate slope and aspect from that.


• Repeat 300 times (batch or script)

[mortazapirouz]

Thanks Luke Pinner
I will try.