Science Article

This investigation examines soil transport, which looks at the amount of sediment and nutrients entering the stream and the amount of sediment and nutrients that are transported downstream.

Balanced streams will not show areas of extreme erosion or deposition, and where they have gravel, cobble, or boulder streambeds, the streambed will not be "chocked" with fine materials such as silt or sands.

In ponds, this is seen as erosion from the removal of shoreline vegetation, wave action, and ice that destabilizes the soil, resulting in increased rates of erosion and migration of materials down the shore. This investigation is not appropriate for sites that have parent materials of either sand or silt.

Protocol

For streams, examine the areas in riffles. For ponds, examine a transect that is out 1 m (3 ft) from the shore running parallel to the shore.

Investigation

Determine what type of parent material the bottom has: sand, gravel, or cobble/boulder. To do this, examine the largest natural particles sticking up from the bottom into the flow. Typically this represents the largest 10% of the particles present.

At each sample site, note the percent of the bottom that is covered in particles less than 2 mm (0.08 in) in size; these are known as fines. Use the coverage gauge on the field sheet to assist you in your estimate.

Scoring