This BIODROUGHT calculator allows calculation of the BIODROUGHT multimeric index, which determines the probability that a drying event occurred in the year preceding sampling). The calculation is based on analysis of the taxonomic and functional composition of macroinvertebrate samples taken < 1 year after the suspected flow resumption.
The calculator analyses single samples comprising a list of taxa and their abundances. Either import your data as a CSV (comma delimited) file or manually enter each taxon and its abundance.
If importing a .csv file, enter “taxa names” in cell 1A and “abundances” in cell 1B, with data in cells 2A and 2B onwards. During the calculation, any additional information (e.g. species traits) will be added to your taxa list and any necessary taxonomic adjustments will be made automatically. The taxa in your data file must be included in the calculator database, which you can download HERE. If an entered taxon is not in the database, a warning indicating mismatched names and suggested alternative taxa names is printed.
Ensure the correct season is selected, because the calculator uses different formulas to calculate the index for spring and autumn seasons; the calculator is not suitable for samples collected in other seasons .
The calculator will produce the following output. Further information on each metric can be found HERE:
|VALID||LIMITED VALIDITY||NOT VALID|
|Biological sample characteristics|
|Czech saprobic index||≤2.3||2.3 - 2.7||>2.7|
|Sum of indicator taxa weights||≥12||12 - 10||<10|
|Number of individuals||>300||100 - 300||<100|
|Acidity class (Braukmann & Biss 2004)||4 - 5|
|Strahler order||1 - 4||5 - 6||>6|
|Altitude (m a.s.l.)||200 - 500||500 - 800||>800|
|Ecological status||high to moderate||poor||bad|
|Water body alteration||artificial, heavily modified|
|pH||>6.5||6.5 - 5.5||<5.5|