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Salt Creek Watershed Project

Waverly High School Salt Creek Watershed Study


The channelization of a river can have large effects on the plant, animal, and bacteria life in and around the creek. The point of the biology testing is to prove how many individual organisms are present, and how many kinds of each organism there are.

By looking at the quadrats, and pressing plant tests, the diversity and frequency of plant life wiyhin Salt Creek is shown. Plant life may be related to the amount of animal development in one area since low plant life can lead to a decrease in animal population.

When looking at the results of the soil samples, animal tracks, sweep for insects, and microinvertebrate tests, information is shown about the relationship of animals to the channelization of Salt Creek. This relationship shows that channelization can affect the diversity and frequency of animal life along the creek. The fecal coliform test shows that channelization also has a direct link to the frequency and diversity of bacteria within the creek. If there is an increase in the amount of bacteria in the creek, the oxygen level drops. All of the tests that are completed deal with the frequency and diversity of plant, animal, and bacteria life along the Salt Creek. These tests show that channelization can lead to a decrease or increase of numbers depending on the place or flow of the creek.

The influence of channelization on the biology of a creek can have a direct link to the chemistry of the creek as well. The first in a series of seven chemistry tests is dissolved oxygen. This shows the amount of dissolved oxygen in the water that is produced by air and rocks. This test is important because without 100 percent saturation of the oxygen, it is hard for fish to live in the creek. The things that affect the percentage of dissolved oxygen in the water are water temperature and air pressure. These things need to be taken into account when determining the percent of saturation.

The other six tests that were completed measure the dissolved oxygen level in the creek as well. By looking at the phosphate and nitrate tests, the comparison of rising levels of each of them is comparable to the level of algae in the creek. When the phosphate and nitrate levels increase, a rise of algae is shown which affects the dissolved oxygen level. The dissolved oxygen level is affected when algae die, and bacteria decompose it.

The outcome of the turbidity tests showed the cloudiness of the water. When turbidity is high, the temperature of the water goes up which makes the dissolved oxygen level decrease. The temperature of the water was also determined in a separate test, and was affected by thermal pollution from sources such as plants and factories. When the water temperature falls, the dissolved oxygen level in the water will rise. The biological oxygen demand (BOD) test shows the amount of oxygen that the bacteria in the water is using. The consequence of having high bacteria in a creek is that the amount of oxygen in the creek diminishes.

The final chemistry test completed at Salt Creek was the pH test. The amount of pH in the water also affects the number of living organisms in the creek. For example, most fish need a pH level of seven to nine in order to survive, so calculating the level of pH can be a vital factor in the survival of organisms in the Salt Creek. The chemistry tests showed information about the relationship of the pH factor to the water, but information about the soil is also needed.

The Earth Science classes tested the soil chemistry around Salt Creek to obtain information on its productivity for plants. A pH reading was taken on the soil to determine the acidity of it. The pH level can be affected by nutrients in the ground consisting of nitrates, phosphates, calcium, magnesium and potassium. If any of these nutrients is too high or too low, the pH level will be affected. By looking at the results of the "Ca + Mg," "K," Nitrates, and Phosphates tests, information can be recorded on how much affect these nutrients have had on the pH level. If there is a high concentration of calcium, magnesium, and potassium the pH level will be more basic. If there is a low concentration of these nutrients, the pH level will be more acidic, which means lime deposits need to be added to the soil. The results of the Lime Estimation and Requirement test showed the amount of lime that would be needed in order to make the pH level normal again. Adjustments of lime deposits may need to be made accordingly with the outcome of the tests.

If too many of these elements are deposited in the soil, salinity will result with a "burning" of the plants. A salinity test was conducted to determine the amount of nutrients present in the soil, and whether alterations are necessary.