Techniques of trend analysis for monthly water quality data

  title={Techniques of trend analysis for monthly water quality data},
  author={Robert M. Hirsch and James Richard Slack and Richard A. Smith},
  journal={Water Resources Research},
Some of the characteristics that complicate the analysis of water quality time series are non-normal distributions, seasonality, flow relatedness, missing values, values below the limit of detection, and serial correlation. Presented here are techniques that are suitable in the face of the complications listed above for the exploratory analysis of monthly water quality data for monotonie trends. The first procedure described is a nonparametric test for trend applicable to data sets with… 

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