Students used a Tualitin watershed model table. Ely explained it as a "3D map" to help test theories about erosion. The model allowed the students to simulate what happens when rain or other types of precipitation mix with contaminants on the ground.
The students then tested mitigation strategies such as grasses, sedges and rushes. They modelled these with felt and other materials like foam to see if erosion and runoff could be better controlled.
The second part of the visit was an erosion slide show which depicted real-life examples of the effects of erosion.
What is erosion?
The movement of rocks and soil by:
Wind-happens in dry areas with little vegetation, farm fields and deserts
wind moves sediment around, changes the forms of rocks
Ice-snow settles and never melts away, glaciers are formed over many years and as they slowly melt they slide over land and break up rock
glaciers also form valleys
Water-river is cutting through ground as it flows. The reason for a muddy river is soil, sediment being moved by erosion
Waves- over time waves wear away rock and move sediment of landforms along the coast
Gravity-heavy weight, cliffs, slopes, avalanches, landslides, steep slopes cause land to erode