Creating EC/Elevation Derivatives

This article will show how to create EC/Elevation Derivatives. First, you will need to import the data.

Importing Data: EC

Import the EC data via one of these formats:

• TerraLogga - a PCT software that runs on a tablet. Import the .terralogga file.
• TSM - import and export CSVs from the TSM software.
• Veris - import .dat format for EC and pH.
• Various CSVs will work. A CSV with correct column headers is critical. The most basic ones are listed below; however, there are many others that will work. Contact us for the full list.

• Longitude
• Latitude
• CONDUCT_05 (this will create a layer called DualEM 50cm Raw)
• CONDUCT_1 (this will create a layer called DualEM 100cm Raw)
• Time - in the format yyyymmdd

Importing Data: Elevation

Import with these settings in the Import UI.

1. If you don't have a season for your data then choose All Seasons.
2. Click Choose Files to locate the files on your hard drive or USB
3. Click Import

Once data has been imported you can run the filter to adjust and clean the data in Data Editor

Once data filters have been run for the first EC depth hit create to create a raw layer. (note: TerraLogga projects typically need a -2 to -4 data shift) You can then click 'Create' to create the final layer that will be used in other apps.

Repeat filters and create layer steps for other depths.

Elevation typically doesn’t need any filters applied. Once elevation is created, there are a number of derivatives that can be created.

Slope is rise over run or how steep a given area is. Pixel number is the distance from a given point used to calculate the slope.

Aspect is the angle of the terrain in relation to the sun. The lighter color will be south facing darker north facing.  

Landscape Change is a given point's height relative to its surrounding area, which is why you will see both negative and positive numbers. The more negative a number the more likely water will move toward the area. The higher the number the more likely an area is to shed water. The radius is the distance from a point in meters that the system looks to make the calculations. Checking exhaustive averages will take longer to create but can do a better job of finding microtopography issues.

Depression calculates anywhere water can’t run off and will potentially pool. Checking 'Depression values are Negative' will flip the color scare making any depression a negative number. Unchecking 'Non-depressions set to Zero' will leave areas with no depression blank rather than filled in. Only include values >= will change any value greater than the number entered in meters to a non-depression area.  

The directional derivatives are geared more for gravity irrigation or ridged/cultivated fields where the direction is the direction in which the rows will naturally move water.