Case Study_ Creating soil property maps with SIE

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					 Case Study: Creating soil
property maps with ArcSIE
 Missouri Soil Productivity Index
           Fred Young
• Provide a case study example of the use of the
  Property Map tool in ArcSIE.
• Stimulate participants’ imaginations about
  creating soil property maps from ArcSIE
            The Property Map tool
Calculates a weighted average property value for each pixel, using the membership
values of each class in the model as weights.

Creates a continuous surface property map.
          Each pixel may have a different value.

                                                                 (choose individual
                                                                  soil models here)

                                    (enter RV soil
                                       property      (individual soil models are listed here)
                                     values here)
                Example with Missouri data

PI values based on RV
soil properties for
each modeled soil.
 Background: Missouri Productivity Index

• Target crop: corn
• Uses soil properties (NASIS RV) to model
  potential crop growth.
  – OM content, depth, AWC, wetness, etc.
• Based on fundamental principles of soil & plant
• Calculated in NASIS as an interpretation.
• Values approaching 1 = excellent yields possible.
• Values approaching 0 = not agricultural soils.
• PI * 1000 used here (e.g., PI of 0.651 >> 651)
Categorical PI       Continuous PI
                     (based on ArcSIE
(SSURGO colored by
                     modeled rules; each
                     pixel may have a
                     different value)
Larger scale view: SSURGO categorical vs ArcSIE continuous
ArcSIE hardened; discrete PI values            ArcSIE Property Map Tool; continuous PI
     Property maps: misc comments
• The property values entered into the ArcSIE Property Map
  Tool are equivalent to NASIS RV’s for a component.
• Assumes linear, continuous relationships among soils and
  soil properties.
   – e.g., a soil that is “half-way” between a soil with a PI of .7 and a
     soil with a PI of .6, will have a PI of .65.
   – e.g. a pixel with a membership of .5 for Alpha silt loam, and a
     membership of .5 for Beta silt loam, will have soil properties
     that are exactly between the RV properties of each.
• Property should be continuous, linear, and not truncated.
   – e.g., depth to bedrock: what to do with soils that are “very
     deep”; >200cm?
   – e.g. water table: what to do with soils without a water table?
   – e.g., pH, Ksat (not linear?)
• Questions? Comments?

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