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Sampling schemes for digital soil survey

Alex McBratney

The University of SydneyAUSTRALIA

• Random catena sampling• Latin hypercube sampling• Fuzzy k-means

kth-order random toposequences

Seed pointUphill section

Downhill section

Odgers, N. P., McBratney, A. B., Minasny, B. Generation of kth-order random toposequences. Computers & Geosciences. (in press)

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kth-order random toposequences

Latin Hypercube Sampling

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Latin Hypercube SamplingA random sampling procedure that 

ensures a full coverage of the range of 

each variable by maximally stratifying 

the marginal distribution

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e Latin Hypercube sampling

• Ancillary information

• Latin hypercube sampling

• 300 soil profiles

Soil survey

• Fuzzy k means stratification

Monitoring in the Gulf CountrQueensland

QLD DNR&W

Fuzzy k-means ofThe environmental layersk = 50

Siteses were constrained to be located within 1.5 km from roads

• HELS useful for legacy data checking and new sampling

• Work needed on validation sampling