Blog Post #8: Research Project Update

• Name of the research project

• Effects of different grasses on the reduction of soil erosion in locally sourced soil.

• Names of the research group members

• Megan Thees, Gretchen Janes, Karina Yu

• Photo of your research in progress

• 

• Update us about the current state of your research project.

• The three types of grass were grown for 2 weeks. When we ran our first test we used a block that was 1.5 inches tall to create a 20 degree slope. We used a plastic cup with 10 holes poked in the bottom as our rain simulator. We used 500mL to water each bottle of grass. The runoff was caught in a beaker and each beaker was observed (water color, amount of dirt in each). We reserved water from each beaker to test the nutrient that were lost from the soil into the water, which we will test at a later date. The dirt was strained out of each beaker by using cheesecloth. The samples were set aside to dry. Megan, Gretchen and Karina each collected samples of soil from 3 different locations, Martha Lake Park in Lynnwood, Washington, 92nd Street Park in Mukilteo, Washington and the last sample was from Eastern Washington. We planted overseed grass in 3 samples of each type of soil, watered and set to germinate. When the caught soil particles dried, the weight was taken of each sample to reveal the amount of soil that was lost during the rain simulation.

• Tell us about your initial results!

• Overseed A pH 8
• Overseed C pH 8
• Overseed B pH 8
• Major league A pH 8
• Major league B pH7
• Major league C pH 7
• Bentgrass C pH 8
• Bentgrass A pH  8
• Bentgrass B pH 8
• Control C pH 7
• Control B pH 7
• Control A pH 7
• 
• After running our first trial of rainfall we tested the pH of all the water runoff of each bottle to see if there were any differences, and our results indicated that the bottles with more grass growing in them had a higher pH/were more basic than our controls with no grass growing in them but the same soil.
• Our first trial that was run at a 20 degree slope did not have the results we were expecting and from the table above you can see that very small amounts of dirt were lost from all our control bottles which was expected, but the results between our grass samples are not all consistent.

• Have you had any revisions to your experiments?

• Yes. We did not get the results we were expecting from our first test run so we are going to revise the test and increase the slope and the intensity of the rainfall. Also since we only have about 2 weeks left for this project we revised our original experiment and are using the grass that grew the fastest because our results from our first trial were inconclusive as to which reduced soil erosion the most. Other revisions also include the testing of pH, water nutrient testing, and soil nutrient testing.

• What do you have planned for the final 2 weeks?

• Tuesday we will run the test with the steeper slope and more intense rainfall. We will also test the nutrients of the water and the nutrients of the soil. We have planted 12 more bottles with the Overseed grass mix, because it grew the quickest, in three different types of soil to see if that has an effect on the plant’s ability to decrease soil erosion. We will test that trial as soon as the grass has grown enough. We will also test and compare the pH and nutrients in the soil and water of the three different types of soils we used for the second test.