Sampling strategy
Sampling strategy - contextEnvironmental samplingSpatial variabilityDevelopment of a sampling schemeSpatial variability -> sampling scheme (1)
Spatial variability -> sampling scheme (2)Temporal variabilitySampling and storage equipmentPotential sources of analyte lossesSample contamination
End of lesson Spatial variability 
sampling scheme
Example for stratified spatial distribution: depth profile of pesticide atrazine in lake Greifensee
Stratification is due to the temperature dependence of the density of water, which is highest at 4°C
Note: small lakes and ponds are typically so shallow that no stratification develops (i.e., always completely mixes)
