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Salt Creek Watershed Project

Waverly High School Salt Creek Watershed Study

Results

After observing the data taken, it can be concluded that the hypothesis was correct. It has been observed that the over-all health of the creek has decreased. The dissolved oxygen level has decreased, but water speed has increased making it hard for living organisms to sustain life.

As the creek passes through Lincoln and into Ashland, the water temperature increases. This could be the cause of the decreased dissolved oxygen level in the water. The data from the water tests shows a drop in the dissolved oxygen level. When these numbers are compared to the temperature level, it can be seen that the increase of the temperature leads to the dissolved oxygen decrease. The chemistry tests show that the dissolved oxygen level was lowest at site four, and the average temperature at the site was one to two degrees higher than at the other sites. The turbidity level was also the lowest at site number four. A decrease in the turbidity level can usually be related to a decrease in temperature, but the overall temperature level increased along the creek. This shows that another factor contributed to the decrease of the turbidity level.

By looking at the results of the water nitrate tests, it can be observed that the levels from site four were the highest. This means that the dissolved oxygen levels at site four's water was the lowest. This is the result of the bacteria breaking down the algae in the creek, as mentioned earlier.

The dissolved oxygen tests show that the highest level was reported at site three. The nitrate results also show that site three has the lowest number of nitrates in the water, and the outcome of the fecal coliform tests show that site three has the lowest bacteria level as well. These things are all related because when the dissolved oxygen level is high, the level of harmful elements, and the level of bacteria decrease in the water. These tests prove that a high level of dissolved oxygen is needed in order for the water to remain healthy.

The results from the soil tests show a decrease in the calcium and magnesium levels. In a normal scenario, both of these levels should go up, but they actually decrease along Salt Creek. This indicates a decrease of the soil quality. The calcium and magnesium levels are lowest at site four which should have decreased the pH level in the soil. The pH level actually increased, so there is another contributing factor to these numbers. The rise in nitrates, potassium, and other soil elements has made the soil's salinity rise, which may be a contributing factor to the decrease of dissolved oxygen. When the soil's salinity level increases, the chances of productivity decrease. As pH goes up, the ability for the plants to absorb water decreases.

The results of the biology tests show that when the Salt Creek travels from Lincoln to Ashland, the number of plant and animal life has significantly decreased. This decrease of organisms is due to the lack of plant life in the area, which is due to the high salinity of the soil. When the plant life decreases in an area, the number of animals and insects attracted to the area will also decrease. The diversity of the animal life has decreased as well, which means the conditions along the creek are no longer ideal for the survival of many species.

The tests that were completed along the Salt Creek were used to determine the health of the water, health of the soil, and the productivity of organisms in the area. The tests are all related to one another and are important in studying the health of an environment. The results of the tests show that the quality of the environment around Salt Creek, and the water in Salt Creek itself, have been affected by changing levels of certain elements. These elements have all been affected by channelization, temperature, or the climate that the water is in. The tests proved that channelization leads to changes in the erosion of the soil around the creek and water speed which can have a large effect on the quality of the water and soil. These changes can affect animal life which was proved to have decreased along the creek. With some help, hopefully something can be done to restore the overall health of the creek to insure new plant growth, and the return of animals.