`Assessing the biological quality of fresh waters: RIVPACS and other techniques', edited by John F. Wright, David W. Sutcliffe and Mike T. Furse.
`Assessing the biological quality of fresh waters: RIVPACS and other techniques', edited by John F. Wright, David W. Sutcliffe and Mike T. Furse. Published by the Freshwater Biological Association, Ambleside, June 2000. ISBN 0 900386 62 2. 400 pages. Price £40 softback, £60 hardback (including p. & p.).

Standardised Sampling and Processing

It is important that the macroinvertebrate community at all reference sites is sampled using a standard protocol. The measurement of the various environmental variables must also be carried out using a standard methodology. This is to ensure that sampling and measurement error are minimised or at least are uniform across all sites.

In the UK RIVPACS, reference sites were sampled using a three-minute active kick sample with a 900 μm mesh pond net, where all in-stream habitats within the site were sampled in proportion to their occurrence.

Macroinvertebrates were identified to species level or to the lowest possible taxonomic unit. The log abundance category was recorded at family level:

0: not present
1: 1-9 individuals
2: 10-99
3: 100-999
4: 1,000-9,999
5: 10,000+

The biological sampling and measurement of environmental variables at a new test site must also conform to that used for the reference sites. This is to ensure that the predicated fauna can be legitimately compared to the observed fauna.