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Taxonomic predictions
RIVPACS can provide taxonomic predictions at
five taxonomic levels:
• TL1 = taxa recognised by BMWP indices
• TL2 = taxa recognised by WHPT indices
• TL3 = all families included in RIVPACS
• TL4 = all species included in RIVPACS species
• TL5 = mixed taxon level (a practical, mainly
species level of analysis but with less
easily recognised species identified to
higher taxonomic levels)
And for each season:
• Spring = March, April and May
• Summer = June, July and August
• Autumn = September, October and November Compare
For every taxon at every taxon level in each season, RICT Compare calculates the significance and
RIVPACS predicts the following: direction of differences between two classifications.
• Numerical abundance This is useful for comparing whether the status of
• Log 10 abundance category: 1–9, 10–99, 100–999, a site has changed between surveys or if there is
1000–9999, >10,000 a significant difference in class between two sites,
• Probability of occurrence such as control and impact sites in an investigation
(eg upstream and downstream from suspected
• Probability of each log 10 abundance category
pollution). Compare provides information about the
statistical significance of differences in Ecological
Follow guidance in the RICT2 User Guide, which
you can download from the User Guides page of the Quality Ratios, taking into account sampling and
RICT/RIVPACS web page https://www.fba.org. analytical error. It also gives the probabilities of each
uk/rivpacs-and-rict/rict-rivpacs-user-guides combination of class for each pair of samples being
compared.
All indices prediction Downloading and editing
RICT2 programs
RIVPACS currently predicts a wide range of biotic
indices, including most of the indices described in this
handbook. RICT2 programs and internal data files can be viewed,
modified and downloaded from the RICT2 website.
RICT software cannot currently adjust and convert The programs have been written in R so that they can
RIVPACS predictions into predictions of WFD be edited by researchers.
reference values (Chapter 3 Section 3.3) except for
the forms of WHPT ASPT and WHPT Ntaxa that are Further advice is given in the RICT2 User Guide and
used for classification. in the Build Guidance which can be downloaded from
the RICT/RIVPACS user guides web page https://
www.fba.org.uk/rivpacs-and-rict/rict-rivpacs-
user-guides. The RIVPACS reference database
used to build RIVPACS has been uploaded to the
Reports page of the RIVPACS/RICT website https://
www.fba.org.uk/rivpacs-and-rict/rivpacs-rict-
resources. Development of the current taxonomic
prediction and prediction of other biotic indices are
described in Davy-Bowker et al. (2010). (32)
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