Page 95 - Freshwater-Biology-and-Ecology-Handbook

THE THREE-MINUTE HAND-NET SAMPLE

Is the mean depth of the watercourse > 80cm?
(averaged across the 3 depth measurements at ¼, ½, and ¾ channel-width in the sampling area)

No Yes

Is the width of the watercourse > 15m?
(measured across the sampling area)

No Yes

Manual search part 1 1-minute manual search 1-minute manual search

Marginal sweep Marginal sweep
1-minute active sampling 1-minute active sampling
Kick sample with pond net
Use a combination of kicking
and sweeping depending on
the substratum, current and
habitat conditions. Sweep sample with Airlift sample
long-handled pond net
Sample all habitats in Sample using a standard
proportion to their cover. Reach out as far as safely airlift deployed from a boat.
possible with the LHPN from
3 minutes of active sampling. the channel or bank to sample Sample all habitats in
the benthos. proportion to their cover.
3 minutes of active sampling.
Sample all habitats in
proportion to their cover.
3 minutes of active sampling.
Manual search part 2

Figure 2.4
How to choose the appropriate invertebrate sampling method for RIVPACS

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