Laboratory Analysis - Planet WGSW-24010 User Manual

4.6.11 Comments
In this section report any unusual features of the survey length, eg excessive growth of a
particular macrophyte or a lack of macrophytes with no obvious cause. Record any problems
encountered while surveying. Note distinguishing features of the survey length so that it can be
relocated on subsequent occasions.
4.6.12 Assigning a measur e of confidence in the compar ability of sur vey lengths
When undertaking surveys to assess downstream changes in trophic status, it is necessary to
assess how physically comparable are the sites being compared. Having undertaken both the
sketch map and the physical inventory, identify on a scale of 1 to 3 how comparable the sites are
and record this on the standard record sheet (Appendix 5). This assessment should be recorded
at the time of survey or shortly afterwards.
The factors under consideration for comparison are Width, Depth, Substrata, Habitats, Shading,
Water Clarity and Bed Stability.
· If 5 or more of these characteristics are similar for more than 75% of the site for each pair
of survey lengths then assign category I.
· If 3 or 4 of these characteristics are similar for more than 75% of the site for each pair of
survey lengths then assign category II.
· If 2 or less of these characteristics are similar for more than 75% of the site for each pair
of survey lengths then assign category III.
It is strongly recommended that surveys with a suffix of confidence of III should not be used for
interpretation of trophic status — ie there is sufficient cause for concern that any differences in
MTR between sites may be due to factors other than nutrient enrichment.
4.7 Labor ator y Analysis
4.7.1 Equipment
Binocular microscope, microscope slides
Hand lens ´ 10
White tray, forceps, dissecting needle
Identification keys
Plant press
Mounting paper and glue
Refrigerator
4.7.2 Refer ence collection (her bar ium)
A reference collection of dried/pressed macrophyte specimens should be compiled and added to
as new species are found in the area. Fruiting and flowering parts should be included. Verify
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