Making a plankton sampling net
Plankton nets are used to sample life in the limnetic zones of a lakes. Knowing the area of the opening and the distance that net is pulled through the water provides a volume sampling of a lake. This, taken with a bathometric analysis gives insights into a lakes bioproductivity. The plankton net is made of a metal ring that remains perpendicular to the direction of pull with a long fine tapering mesh net that directs objects into a sampling jar that can be unscrewed to be removed.
Materials
1 meter long 1/4 inch galvanized rod.
1 meter square fine mosquito mesh
3 inches 1 1/2 pvc pipe with male threaded fitting
8 inch 1 1/2 clear polycarbonate pipe with female fitting
1 1/2 bias tape
1 1/2 clear cap
1 1/2 pipe clamp
30 feet 1/8 nylon line
dental floss
f the water.
Plankton nets are used to sample life in the limnetic zones of a lakes. Knowing the area of the opening and the distance that net is pulled through the water provides a volume sampling of a lake. This, taken with a bathometric analysis gives insights into a lakes bioproductivity. The plankton net is made of a metal ring that remains perpendicular to the direction of pull with a long fine tapering mesh net that directs objects into a sampling jar that can be unscrewed to be removed.
Materials
1 meter long 1/4 inch galvanized rod.
1 meter square fine mosquito mesh
3 inches 1 1/2 pvc pipe with male threaded fitting
8 inch 1 1/2 clear polycarbonate pipe with female fitting
1 1/2 bias tape
1 1/2 clear cap
1 1/2 pipe clamp
30 feet 1/8 nylon line
dental floss
f the water.
Construction
- Bend the rod into a uniform circle and weld the ends together
- Fold the material in half, and sew the mesh into a taper a half meter wide at the top tapering to 2 1/4 inches at the bottom.
- Fold the net over the ring and sew around the rod. Then fold the bias tape material over the rod and sew in place.
- Screw the capture bottle onto the PVC threaded end.
- Thread dental floss loops at four evenly spaced locations around the ring. These form the pull places for dragging the net.
- Tie 30 to 34 inch pieces of line onto these dental floss loops.
- Drag the net and adjust the ties so that the net moves perpendicular to the surface o