Chemistry

Environmental Soil and Water Chemistry

In order to determine the healthiness of environments that we studied, chemists conducted tests on significant macronutrients in the soil and water. The research that previous scientists have done has helped us understand the meaning of the data that we have collected.

The tests that both Soil and Water Chemists conducted were pH, nitrates, and phosphorus levels. The pH levels of the soil and water determine the acidity or alkalinity of the water and soil. pH is measured on a scale of 0 to 14, 0 being acidic, 14 being alkaline, and 7 being neutral. Levels of pH can be impacted by industrial waste, agricultural runoff, and pollution (Nelson, 2018). The pH of soil and water helped us determine the types of plants that could grow in certain environments because different plants need different pH levels to survive. Another test that all the chemists ran was a nitrate test. Nitrogen is a key component for life on Earth, and it is needed by all plants and animals to survive. If nitrate levels are too high, it can be fatal for wildlife in that area. Decomposing plants and animals release nitrates into the water and soil (The Environmental Literacy Council, 2015).

The last test that both Soil and Water Chemists conducted was for phosphate levels. Phosphates are needed for growth in plants and animals. This compound plays a critical role in cell development. High levels of phosphorus can cause overgrowth of plants and animals and can lead to high levels of bacterial activity (BD Editors et. al, 2019). Excess phosphorus can come from human and animal waste, farming runoff, and pollution (Science Learning Hub, 2013).

Two tests that only Soil Chemists conducted were moisture and potassium. Moisture levels are important because different plants vary in different areas because of the soil moisture. For example, plants and animals that are adapted to dryer conditions could not survive in wet areas like wetlands. Potassium is needed by plants and animals to form enzymes, which help make chemical reactions go faster (Hillel, 2008).

Water Chemists conducted tests for ammonia, turbidity, and dissolved oxygen. Ammonia is used in fertilizer and in the production of plastics, paper, and rubber. High levels of ammonia indicates polluted water (Earth Force Low Cost Water Monitoring by earthforce. org).

The turbidity test is a measure of how cloudy the water is. It is a way of looking at how much clay, silt, microorganisms, and organic matter are suspended in the water. Dissolved oxygen measures the amount of oxygen in the water. It is measured in percentage based on the temperature because colder water can hold more oxygen and warmer water holds less. Pollution, such as dumping and agricultural runoff, can fill up the water with toxins instead of oxygen.

https://www.sciencelearn.org.nz/resources/961-the-phosphorus-cycle https://enviroliteracy.org/air-climate-weather/biogeochemical-cycles/nitrogen-cycle/ https://www.sciencedirect.com/topics/earth-and-planetary-sciences/potassium

Soil Chemistry Methods

Geologists collected three soil samples from three different locations and gave them to us. To prepare the soil, we mixed distilled water with floc-ex. We did this for each soil sample. We waited until the soil settled and a semi-clear solution sat on top of the soil in the tube. Then, we used the solution to perform the three tests.

For our nitrate test, we added a nitrate tab to some of the clear solution. Once this test was completed, we compared the color of the test to the color chart and recorded the data. For our phosphorus test, we filled a tube with a mixture of the clear solution and distilled water. We then added a phosphorus tab and waited for the color of the liquid to develop. Then, we compared the color of the solution to the chart. For our potassium test, we added a potassium tablet to some of the clear solution and let it sit until dissolved. Then, we compared the color of the liquid to the color chart. The last thing we did was find the pH and moisture of the soil. To do this we used a soil probe and recorded the results (LaMotte Company, 2019).

As Soil Chemists, we used many different tools to conduct our tests. Our first tool that we used was a 50 mL clear test tube. We also used many 10 mL clear test tubes. We used pipettes to transfer liquids from one place to another. For the nitrate test we used silver sun proof sleeves. We also used a soil probe which told us the pH and moisture levels of the soil. For our macronutrient tests, we used nitrate, phosphorus, and potassium test tabs. Our last tools were latex gloves and safety goggles, which we used at every site study.

Water Chemistry Methods

We began our site studies by going to a source of water and collecting a sample in a small plastic cup. Then, we took the temperature of the water, by holding the temperature strip under water for a minute. For our dissolved oxygen test, we used a small tube and held it under the water for 30 seconds and compared the test to the color chart. To discover the amount of nitrates in the water, we filled a tube with water and added a tab. Then we inverted the test and compared it to the color chart. The last test that we conducted was ammonia. We filled a test tube and added a #1 tablet and a #2 tablet and inverted until dissolved. Then, we let the test sit and compared it to the color chart (Earth Force Low Cost Water Monitoring by earthforce.org).

For nitrate, phosphate, and ammonia tests we used 10 mL test tubes that were long and clear. We also used a small glass tube for the dissolved oxygen test and a large 20 mL tube for the turbidity test. We used a temperature strip for testing the temperature of the water. For most of our tests we used tabs that dissolved in our solutions. For the turbidity test, we used a sticker that we attached to the bottom of the tube to help us determine the clearness of the water. We also used pipettes to transfer our solutions. Lastly, we used gloves and goggles to protect our eyes and hands from the chemicals.

Soil Chemistry Data

In North Carolina, we conducted five site studies at Black Balsam Knob, Graveyard Fields, Fontana Lake, Goose Creek, and Fort Macon. We also did a partial site study at the Salt Marsh, which was near Fort Macon.

The first site study that we did in North Carolina was on top of Black Balsam Knob. The average pH was 7, which is neutral. The soil was dry with a moisture reading of 1. The nitrate levels were about 40 lbs. This means that there was a medium amount of nitrates in the soil. The phosphorus levels were around 20 lbs; this is a low amount. The potassium levels were medium, which is about 160 lbs. The second site study was at Graveyard Fields. The pH was 7. The moisture levels were 3. The nitrogen levels ranged from 0 - 160 lbs. The phosphorus levels were around 20 lbs and potassium levels were 80-160 lbs. The third site study in North Carolina was at Fontana lake. We did not record the pH and moisture here because of a miscommunication between the geologists and chemists.. The nitrate levels were 0. The phosphorus levels were medium, around 60 Ibs. The potassium levels were 60 - 160 lbs. The fourth site study in North Carolina was Goose Creek. The pH there was 7; however one of our tests was 3, which stood out to us because that is very acidic. The

moisture had a large variation because there were levels of 0, 4, and 8. The nitrogen levels were 40lb. The phosphorus levels were 20 lbs. The potassium levels were also low, which is about 40 lbs. The fifth site study was at Fort Macon. The pH was 7 and the moisture was 1. The nitrogen levels were zero, the phosphorus levels were 20 - 64 lbs, and potassium levels were 40 - 160 lbs. Our last site study was at the Salt Marsh. The nitrogen was zero. The phosphorus was 20 lb, and the potassium was 40 lb.

Water Chemistry Data

Our first site was Black Balsam Knob and there was no water. The next study was Graveyard Fields. The water was 18 degrees celsius, and the dissolved oxygen was 71 - 90 percent saturated. The nitrates were yellow which means that there was none. The pH in the water was neutral at 7. The phosphate was 1 ppm and the turbidity was less than or equal to 0 JTU, which means the water was clear. The ammonia was 0 ppm. At Fontana Lake, the water was 22 degrees celsius, the dissolved oxygen was 91 to 110 percent saturated, and the pH was 7. The phosphates were 2 ppm, nitrates were 0 ppm, and the turbidity was 0 JTU. Lastly, the ammonia was 0 ppm. At Goose Creek, the temperature was 24 degrees celsius, the oxygen was 91 to 110 percent saturated, and the nitrates were 0 ppm. The pH was 7, the phosphates were 1 ppm, the turbidity was less than or equal to 0 JTU and the ammonia was 0 ppm. The next study was at Fort Macon. The temperature was 22 degrees celsius, the dissolved oxygen was 91 to 110 percent saturated, and the nitrates were 0 ppm. The pH was 8, the phosphate was 1 ppm, the turbidity was 0 JTU, and the ammonia was 0 ppm. Our last site study was conducted at the Salt Marsh. The pH of the water was 7, and the phosphate was 2 ppm.

Soil Chemistry Conclusions

The purpose of studying the soil in many environments was to discover the levels of different key components that must be incorporated into the soil for it to be healthy. The presence of the different amounts of macronutrients, moisture, and pH in the soil helps determine the animals and plants that can survive in that environment. The majority of our sites contained evidence of no nitrates in the soil samples. This data suggests that there were many healthy and diverse plants in the environments. Plants absorb nitrates in soil, which causes the amount of nitrates to decrease and the rest is taken away by runoff (BBC, 2019). There were low to medium levels of potassium present at our sites. Plants that lack potassium do not have the energy to properly grow (Brady et. al, 1996). This shows that medium levels of potassium are healthy and good for the soil and plants. The phosphate levels at the sites studies ranged from low to medium, which is normal and met the needs of most plants in the area.

At many of our site studies we made connections with botanists. At Goose Creek State Park, we were given a soil sample in the sand near the water. The location of that soil sample had a pH level of 3, which is very acidic. The botanists also noticed that there were many

Loblolly pine trees and Loblolly trees thrive in acidic soil. At Fort Macon State Park, we made connections with the Botanists and Geologists about how there were no trees; this is because the soil was made up of sand particles. The roots of trees cannot hold strongly enough in the sand; and when the soil erodes, trees are not able to hold themselves up by their roots.

Water Chemistry Conclusion

Our first test is dissolved oxygen which is the amount of oxygen in the water, which we converted to the percent saturation based on the temperature of the water. At Graveyard Fields, the oxygen levels were good with a 71 to 90 percent saturation. This conclusion was also supported by the zoologists finding numerous salamanders. For nitrates, all the sites in North Carolina had no nitrates in the water which reads yellow. Having some nitrogen in the water is important for some plants and animals to survive. This should be monitored by future chemists. The pH ranges from 7 to 8 in NC which is great because it is neutral. It means that most animals can survive because the water is not too acidic or alkaline. The next test is phosphate; it ranged from 1 ppm to 2 ppm throughout North Carolina. 1 ppm being the best and 2 being good. High levels of phosphates can lead to overgrowth. For turbidity, the water was outstanding in terms of how clear it was. All the tests were less than or equal to 0 JTU which means there was little to no sediment in the water. The last test was ammonia. All sites tested negative for ammonia, which is good because high levels indicate polluted water (Water Chemistry, 2019).

One of our connections was with the Zoologists, specifically at Graveyard Fields because they found mayfly larva which indicates the water was clean which also connects with our data reading the water really clear and clean. At the Salt Marsh, the water was more alkaline. This made a better environment for the fiddler crabs to live in. At Fort Macon, there were many ghost crabs. The water was neutral, and this shows that ghost crabs can easily live in neutral waters.

Advice for Future Chemists

There are some things that should be kept in mind when conducting site studies. It is important to stay organized. This makes site studies easier and more efficient. For soil chemistry, think about preparing the tests before receiving the soil samples from the geologists because it will make the tests go faster. Be mindful of the equipment because some of the tools are expensive and it would be disappointing if it broke or a piece of equipment got lost. Avoid sitting too close to the ocean or in a risky spot because there might be a chance that equipment can get lost or ruined. As a group, we would have liked to investigate the Salt Marsh further and perform a full site study for soil and water chemistry. Another tip is to work as a group. Take turns doing water and soil chemistry because it helps to better understand what others in the group are writing.