Assessing the Slakes Cell Phone Application against the Eijkelkamp Wet Sieving Method and other Soil Indicators in Western Cape Soils of South Africa
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Abstract
Soil has chemical, physical and biological aspects. Aggregate stability is an indicator of erosion susceptibility and is influenced by, amongst others, management practices and climate. The Slakes App measures aggregate stability by measuring the slaking speed of aggregates, providing a stability index. It is an easy and cost-effective way to measure an aspect of soil quality. The aim of this study was to compare the Slakes App with the Eijkelkamp® wet sieving aggregate method in three different locations in the Western Cape. Various other tests were simultaneously conducted on the samples. The results showed significant correlation between the two methods for aggregate stability (r=0.60, p < 0.0001). It showed correlations with other soil health aspects tested, making it a good choice for an indicator that seems to link many soil functions. The results obtained with this free cell phone application correlated well with an acknowledged laboratory-based method; thus, farmers can monitor an essential aspect of soil, knowing that it was validated in African conditions. It is recommended that slakes should not be used in isolation and comparisons should be within the same soil, management practice and season.
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Copyright (c) 2026 Anélia Marais, Annemarie van der Merwe, Marieta van der Rijst (Author)
This work is licensed under a Creative Commons Attribution 4.0 International License.
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