Select a reference point in the middle of your site and on one bank drive a peg into theground.
• Attach the tape measure to the peg and lay it out taut across the stream. Anchor the farend with the second peg.
• Divide the width of the stream (water's edge to water's edge) into 10 equally spaced
intervals.
• Move out to the first point across the transect (this will be near the water's edge on one side of the stream). Bend down to lightly touch the bed sediments without looking at what is there. Ideally, pick up the first stone that you touch. If it is too big to retrieve, then take the nearest one that can be picked up. If you touch a small silty or sandy patch among the cobbles, then also take the nearest stone that can be picked up.
• Place the stone on the white tray with a small amount of stream water and return it to the stream bank.
• Place the ring on top of the stone to define a circle in the centre, or as near as possible to
the centre, of the stone.
• Scratch a mark on the stone around the outside of the ring with the tip of a scalpel
blade. Then, scrape away from the outside of the ring all the surrounding periphyton.
• Remove the ring and then scrape off as much periphyton growth as possible from
within the circle and rinse it off the scalpel into an appropriately labelled container.
• Scrub the defined area for ~30 seconds with a toothbrush then remove the slurry from within the circle using the small pipette (Figure 8).
Select a reference point in the middle of your site and on one bank drive a peg into theground.• Attach the tape measure to the peg and lay it out taut across the stream. Anchor the farend with the second peg.• Divide the width of the stream (water's edge to water's edge) into 10 equally spacedintervals.• Move out to the first point across the transect (this will be near the water's edge on one side of the stream). Bend down to lightly touch the bed sediments without looking at what is there. Ideally, pick up the first stone that you touch. If it is too big to retrieve, then take the nearest one that can be picked up. If you touch a small silty or sandy patch among the cobbles, then also take the nearest stone that can be picked up.• Place the stone on the white tray with a small amount of stream water and return it to the stream bank.• Place the ring on top of the stone to define a circle in the centre, or as near as possible tothe centre, of the stone.• Scratch a mark on the stone around the outside of the ring with the tip of a scalpelblade. Then, scrape away from the outside of the ring all the surrounding periphyton.• Remove the ring and then scrape off as much periphyton growth as possible fromwithin the circle and rinse it off the scalpel into an appropriately labelled container.• Scrub the defined area for ~30 seconds with a toothbrush then remove the slurry from within the circle using the small pipette (Figure 8).
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