By: Patrick Troyer, Education Specialist
Fourth grade students at Oakwood Elementary have built upon their knowledge of erosion, weathering, deposition, and pollution via two presentations recently. First, students learned about the changing landscape of the Earth and the forces such as erosion, deposition, and weathering that work together to either construct or transform our environment via the Streamulator presentation. Erosion knowledge was furthered via the “Just Passing Through” program where students learned about runoff, water/wind erosion, as well as pollution and how plants help to lessen the impact felt by these forces.
In the “Streamulator” program, students learned that the surface is the earth is continually being changed via erosion, weathering, deposition in addition to earthquakes and volcanoes. Weathering is breaking down or dissolving rocks and minerals on the earth’s surface. Agents of weathering include water, ice, salt, plants, animals, and temperature fluctuations. Students were asked if weathering is constructive or destructive? It is in fact destructive as it is breaking rocks and minerals down. Erosion is another force changing the landscape of the Earth and is the process or carrying away sediment on the Earth’s surface via water, wind, glaciers, or gravity.
Water erosion is one of the main forces of erosion at work. It is most destructive during heavy rain events that wash bare soil away to create scenes such as gullies in farm fields. Rivers have a steady flow of water and work to break up particles to carry them downstream or erode the coastline away. Wind erosion happens when the soil is dry and the ground has no cover which makes it very light and easily carried away by wind. Soil is removed from one area and deposited in another. A big example of wind erosion is the Dust Bowl that swept through in the 1930s.
Erosion can be reduced in many ways. Cover crops can be planted to hold the soil in place from water or wind erosion or mulch can be applied around landscaping to have the same effect. Windbreaks can also be used which is simply a line of trees planted around a field or property to slow down the wind.
One way students visualized the power of erosion was via the Streamulator. Before viewing the Streamulator, students learned some basics about streams. Flowing water carries energy as it moves across the landscape which erodes a channel that creates bends called meanders. As water flows through these bends, some energy is lost. Meanders absorb the force of the stream moving through the landscape. Students learned some stream terms such as run, meander, deposition, riffle, delta, floodplain, and mouth as displayed on Streamulator.
It was up to the students to label the parts of a stream as they learned in the prior presentation. Students observed how a stream cuts its way through the landscape and forms meanders as well as how water will go to the lowest point in a normal flow and in a flooded environment. After seeing how a stream works, students were challenged to build their own stream & community on the Streamulator using the sand, buildings, bridges, and trees available. The goal was to build a community with a stream and see if their community survived under normal water flow and if a flood came. During the flooding event, students really visualized how powerful water is when it comes to erosion and transformation of the landscape.
In the “Just Passing Through” presentation, student’s knowledge of erosion was furthered with an emphasis on controlling erosion as well as water pollution. Topics such a point and nonpoint pollution were covered along with cover crops and other ways to control erosion such as grassed waterways or conservation tillage.
Students took part in the “Just Passing Through” activity where they took part in “raindrop tag” and “sediment deposit”. As part of the sediment deposit portion, sediment and pollution (poker chips) were spread out on the floor and students were broken up into groups of raindrops and plants. Students first went through a scenario where there were no plants in the landscape as water moved to the stream. The raindrops picked up the sediment & pollution as they made their way to the stream. Data was recorded on how many chips they picked up.
The activity was repeated with the “plants” spreading themselves out on the stream path. When a raindrop came across a plant, they had to circle the plant five times and drop a piece of sediment/pollution with each turn. Data was recorded once the raindrops reached the end of the stream. Students then compared the amount of sediment/pollution collected under each scenario and were easily able to see the impact that plants have when it comes to reducing erosion and pollution from reaching the waterways.
If you would like these programs for your classroom or group, call the Paulding SWCD at 419-399-4771 or email patrick.troyer@pauldingswcd.org
