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Raster data into polygon grid layer

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#1
Katherine_Yates

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Hello all,

I am hoping that some of you may be able to help me. I am trying to prepare planning units to put into a program called MARXAN.

So what I have is a reef platform that is grided into squares (vector polygons). Each square (500m by 500m) needs to contain certain attributes, such as area of seagrass or reef. Where that data is in polygons i have done polygon in polygon analysis.

However I also need to include data for different species of interest. I have point data for a 100 sample sites. I can interpolate across the platform to get a raster layer of what i might expect to find at anyone point. What i dont know how to do is extract an average value from that raster layer for each of my squares.

I have looked at thermatic raster summary but from what i gather it gives me a list of unique values. What i need is an average. one number. 3.5 yellow tail snapper in polygon 35 for example.

I hope my explination makes sense, I am pretty new to this!

Thank you!!!
Katherine :)

#2
BahaZ

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Hello Kathy,

I believe if you have spatial analyst extension for ArcGIS, you can use zonal analysis to do what you are trying to do.

Well that is if you have ArcGIS. Check here http://webhelp.esri....is_by_attribute

#3
Katherine_Yates

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Hello Kathy,

I believe if you have spatial analyst extension for ArcGIS, you can use zonal analysis to do what you are trying to do.

Well that is if you have ArcGIS. Check here http://webhelp.esri....is_by_attribute




Thanks I will check that out :)

#4
Katherine_Yates

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Thank you, yes that works. However i have lots of raster layers and i can only seem to do one at a time that way, if thats how it so be it, but if you know of a way of doing them all at the same time i would appreciate it!

Thanks again




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