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Need very urgent help with LSFactor(USLE)Calculation in ArcGis10(get a strange result

Question asked by geonetadmin on Aug 12, 2012
Latest reply on Aug 13, 2012 by geonetadmin
Original User: Julia.Hauczinger

I wanted to calculate the LS Factor of the USLE (Universal Soil Loss Equation) with the tool Raster Calculator in ArcGis 10.
First, I filled my DEM with the tool Fill. (DEM was calculated in UTM)
Second, I calculated the Flow Direction with the Toll Flow Direction.
Third, I calculated the Flow Accumulation with my Flow Direction as Inputfile.[ATTACH=CONFIG]16865[/ATTACH]
fourth, I calculated the Slope in Degrees by the Spatial Analyst tool Surface and Slope. [ATTACH=CONFIG]16866[/ATTACH]
fifthly, I used the Equation by Moore and Burch 1986: LS = (Flow Accumulation * Cell Size/22.13)^0.4 * (sin (slope/0.0896))^1.3
sixthly: I typed in the raster calculator the equation:

(Power((("FlowAcc" * 92.46745509) / 22.13),0.4)) * (Power((Sin("Slope_Degree" / 0.0896)),1.3))

But my result look very very strange! There a lot of white areas! The Raster is not like cover areas.... It looks like that every calculated value is seperated... It looks like a dotted map....What did I wrong??