Learn to use the 'Range' feature to stratify layers instead of k-means.
In this example, we will stratify a farm into three areas representing high, medium, and low levels of soil carbon using the 'Soil Organic Carbon %' layer and the 'Range' stratification option. This method is effective for Australian CER Soil Carbon projects, where accurate stratification ensures precise carbon stock measurements.
Steps to Stratify Using the 'Range' Option
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Select the Layer: Begin by selecting the layer you wish to stratify.
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Stratify Boundaries: Choose the 'Stratify Boundaries' option.
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Choose Stratification Method: Next to 'Selected Method', select 'Specified Range'.
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Set Number of Strata: Choose the number of strata (divisions) you want for the designated layer.
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Select Metric/Layer: Select the single metric or layer you wish to use for stratification.
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Select Layer Variant: If there are multiple variants of the chosen layer type, select the specific variant you need.
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Specify Range (Optional):
- If you want to set the ranges manually, untick 'Specify Ranges Automatically'.
- If you prefer automatic ranges, leave 'Specify Ranges Automatically' ticked.
- Define Range Breaks and Colors (If Manual):
- When specifying the range yourself, choose each range break and assign a color.
- For example, setting '1' as red will mark every area with less than 1% soil organic carbon in red. Marking 1.5 as orange will mark every area between 1% and 1.5% as orange, and marking 2 will make the areas from 1.5% to 2 % green.
- Anything above the highest value (2% in the above example) will be excluded from the model and appear as a transparent area (see below screenshot). To avoid this, it is recommended setting the highest value as '99'.
- Start Stratification: Click 'Start' to begin the stratification process.
Note: It is helpful to have surveyed the layer beforehand to understand the range of values across the area you are surveying. This knowledge aids in setting accurate range breaks.
By following these steps, you can effectively stratify your area using the 'Range' stratification option, ensuring precise and useful results for your project.