User:Pandamancer

Introduction

For our group experiment we tested the effect of erosion on the water quality of two streams located on the UMBC campus. The first stream is Herbert Run, located near the sport fields on the edge of the main circle; the second is the stream that flows past the edge of Common’s Parking Garage. The reason we chose those specific streams is because of their location on the campus, as well as their basic construct (i.e. the amount of visible erosion, water quality, and any other contributing factors). Considering that the streams are on a campus, meaning that they are exposed to a great amount of human interaction, we thought that they would result in very intriguing water quality levels. Whether we notice or not, those streams are there every day, constantly changing, and we feel that we may be affecting them in a negative way. We hypothesized that: if we test the water quality of these two different streams, then we will notice a difference between the phosphate and nitrate levels, the amount of dissolved oxygen, the pH, and the turbidity levels for both streams, in correlation to the possible effect of the amount of visible erosion. We predicted that the stream with the most erosion (Common’s Parking Garage), will have a more acidic pH, higher turbidity, DO level, and nitrate and phosphate levels. Herbert Run, which has a shallower erosion level that is made of more foliage erosion, we think that there will be a more basic pH, lower level of dissolved oxygen, turbidity, and nitrate and phosphate levels. Herbert Run shows signs of more shallow erosion levels with more foliage, compared to the Common’s Garage stream, which has an immensely steeper erosion level that consists mainly of more soil than the amount of surrounding foliage. The two streams provide a rather balanced comparison, considering we do not have a controlled stream to base both off of. This is why we chose to experiment with the 5 different tests (as stated in our prediction above) to analyze each stream's water quality: dissolved oxygen levels, nitrate and phosphate levels, turbidity, and pH, to give us a broad enough spectrum to compare, while still being interrelated. The dissolved oxygen was chosen to observe the effect that the plant life may have on the water quality, since the foliage is being shifted forward due to the erosion. Therefore, we would expect the DO to be low since the oxygen would be used by the plants, as well as any other biotic life that resides in the stream. Considering that if there is enough sustenance for the foliage to thrive, then there could possibly be enough for fish or insects since Herbert Run seems more inhabitable than that of the Common’s Garage stream. Also, the plants have a tendency to draw in different types of insects, which would then contribute to a decrease in DO levels, as well. The nitrate and phosphate levels, we considered to be connected due to their relation to one another in concern to each one’s amount in the water. Depending on whether one is higher than the other tends to lead to a negative outcome on the quality of the water, which could then affect the other factors of that particular water source. For instance, if there is a high amount of either chemical and none of the other, then the water would be uninhabitable and unable to support any kind of life (Simbio Software, “Nutrient Pollution”). Therefore, testing these two chemicals is substantial in testing the water quality because it can show us whether the amount of erosion has any effect on the amount of run-off being added into the water. The run-off is the main focus with this test considering that with the streams being so close to fields, the fertilizers used would be a major contributing factor to the streams’ water quality. The turbidity was meant as a means for us to test the clarity of the water in relation to the amount of sediments, which would then help us identify the rate of erosion. The stream banks are composed of soil; that soil contains sediments and as the stream banks erode those same sediments are being added into the water. Therefore, the clearer the water, the less sediments are being added at a time. Vice versa, if the water appears murky, then we could predict that the rate of erosion is greater due to the concentration of sediments. Last but not least is the test for pH. PH also factors into the erosion through its relation to nitrate and phosphate levels, as well as, the DO level. If the stream has a low pH, it means that it is too acidic for life to thrive, yet, if it’s too basic, life would have the same difficulty. To keep a level homeostasis, the pH has to be about neutral. The reason why the pH needs to be considered is, again, for the fertilizer factor. With unstable chemical levels, the pH would be out of place, too. This is why such tests were chosen, mostly due to their relation to one another, which combined have an overall key analysis of the water quality.

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Methods

When collecting our water samples we decided to collect from two points of each stream to give us more variability in our data. The only exclusion was the DO test, which were taken from site 2 of each stream where they appeared to have the most erosion. For the first site at each stream, we collected water samples next to the bank that demonstrated the least amount of erosion; whereas for the second site we collected samples next to the area of most visible erosion. Herbert Run had a dense amount of foliage overlaying the tops of the banks, as well as crawling down the slopes towards the water. Some plants had even grown down past the water’s surface. Where there was the least amount of erosion, the bank appeared to be eroded so far back, that the foliage had formed an overgrowing ledge that hung over the sides immensely. The area of most erosion had a steeper drop than the other site, but the foliage did not form as great of a ledge since the plants were able to spread down the longer slope. The water was shallower near the greater slope and deeper near the lesser slope. The stream next to the Common’s Parking Garage had a scarce amount of foliage along its banks. There were a lot of decaying tree trunks and an exuberant amount of roots (both decaying and alive). Farther back towards the path there was a denser amount of plants. Since the area of greater erosion had a slope that was almost vertical, there was not really much leveled area for plants to grow. The roots were able to grow since they protruded out from origins farther back past the actual bank. The area of lesser erosion was only slightly taller and steeper compared to the area of Herbert Run that had the greatest amount of erosion. However, the area of less erosion of the Common’s Garage stream was not as nearly steep enough to match that of the area of greatest erosion on that same exact stream. The reason for the difference is the dividing factor between the two sections. A pipe connects the stream underneath a wooden bridge. The pipe is level with the water surface at the end with the least amount of erosion, whereas, the other end of the pipe leads to a sudden drop-off that rests several feet above the water level that collects in a deep pool at the bottom of the steeper slope. Past the pool, the water tends to level out to match that of the depth of the shallower stream above. The conditions that we tried to hold constant were the types of tests that were conducted, and how they were conducted. Each sample was collected on the same day in the same time period. It was sunny and warm, about late afternoon, so there was no difference in when or how the samples were collected. Each were tested using the same procedure for each test in the same fashion. Other than those factors, there really was not any other way to keep anything constant considering that we were comparing the two streams to one another in retrospect, instead of to a basic main stream since there was none. The independent variable in this experiment is the water quality of each stream. For instance, the pH, the DO level, the nitrate/ phosphate levels, and turbidity of each water sample tested would be considered the independent because it is the subject being tested although it is not being changed in any way because of such testing. This experiment is more of a tested observation instead of a tested change over time with different trials. So, that would mean that the dependent variables are the results of the water quality tests. ________________________________________

Results

The final results of all the data collected from each test done on the water quality of the streams is displayed on a bar graph because the data was basic measurements instead of trials that show progression over time. Although the data is not displayed in the usual line graph format, there are still visible trends among the data. Each test’s results are represented by a different color-coordinated bar based on which particular test is being observed. The bars are also divided up amongst the 4 test sites. So each site has 5 bars that display the results of each test done on that particular stream’s water quality. For the DO levels, the two orange bars, the Common’s Parking Garage: Site 2 had a DO level of 1.2 ppm and Herbert Run: Site 2 had a DO of 1.8 ppm. This is not that drastic of a difference but still different enough to evaluate each site in relation to why the DO levels are as they are. The pH, represented by the tall red bars, shows the Common’s stream site 1 at 6.89 and site 2 at 7.22. Herbert Run’s site 1 was at 7.79 and site 2 was at 7.87. This again shows little difference other than Herbert Run being slightly more basic and the Common’s stream being slightly more acidic. The turbidity, being the purple bars, are only apparent in the Common’s Parking Garage stream, thus leaving Herbert Run with no sign of turbidity in the water at all. The Common’s Parking Garage Stream had 8.8 NTU at site 1 and 2.3 NTU at site 2. Herbert Run had 0 NTU at both of its sites. This is definitely a drastic difference in trends since only one stream reveals a level of turbidity. The blue bar, representing the only trace of phosphate, lies under site 2 of Herbert Run with 0.2 ppm of phosphate. The other remaining sites have 0 ppm of phosphates. Not a drastic difference, but definitely intriguing as to why there is a lack of the chemical in the streams, except for only one particular site. The last bars are the green bars, which represent the nitrogen levels. The Common’s Parking Garage shows 1.5 ppm of nitrates at the first site and 3 ppm of nitrate at the second. Herbert Run had a leveled trend between both of its sites which show 1.5 ppm for each. The average of the results show a leveled amount of nitrogen, except for site 2 of the Common’s stream, which has double the amount of each stream. ________________________________________

Discussion

The DO levels are only displayed in site 2 of each stream but the purpose of doing so was to simply test each stream at the area of most erosion, since the overall purpose of this experiment was to see the effect of erosion on water quality. The other remaining tests were easier to obtain information from and were meant to show more variability on the erosion. The two streams appeared to have rather similar DO levels, varying only slightly. The Common’s Parking Garage: Site 2 had a DO level of 1.2 ppm, whereas Herbert Run: Site 2 had a DO of 1.8 ppm. Therefore, in comparison, Herbert Run, which had a high amount of foliage, had a higher DO level meaning it had less biotic factors taking in oxygen, thus allowing more oxygen to dissolve in the water (Munn, 2007). This is contradictory to the description of Herbert Run in the CERA website. In the web page it describes the stream’s water as being a prime foundation for maintaining and supporting life in its deeper and wider stream sections (CERA, 1997). Perhaps since the DO was taken at the shallower part of the stream where there was the most erosion may indicate that there is less life there but life residing farther downstream. For life to thrive, the DO level has to be stable, balanced by not being too high or low because having either event take place will cause the life within that stream to die (Cooke, 2010). The pH indicates that the Common’s Parking Garage stream was more acidic than that of Herbert Run. For the Common’s stream, site 1 was at 6.89 and site 2 was at 7.22, whereas Herbert Run’s site 1 was at 7.79 and site 2 was at 7.87. The neutral for pH is around 7, so both streams can be seen as neutral, but Common’s stream is lying more towards the acidic end and Herbert Run is lying more towards the basic end, although only slightly. The turbidity reveals a drastic difference between both streams, seeing as how the Common’s stream has actual signs of turbidity, while Herbert Run shows absolutely no sign of turbidity taking place. For the Common’s Parking Garage Stream, site 1 had 8.8 NTU and site 2 had 2.3 NTU. It is a substantial difference between both sites of the same stream, but not as drastic as the difference between both streams’ site 1. Herbert Run’s site 1 had 0 NTU, as did its site 2. These results may indicate that there is barely any sediment concentration clouding the water at the Herbert Run stream, whereas the Common’s Parking Garage stream has a large amount of sediment concentration at the area of least erosion, with the area of greatest erosion having a smaller concentration. This makes sense considering the type of erosion of each stream. According to Atkin’s article on “Erosion and Sediments” it is justified that the more erosion there is the more sediments, especially if the rate of erosion is high (Atkins, 2003). So, the Common’s stream having more soil than foliage on its banks, as well as having steeper slopes than that of Herbert Run, it would be valid to have more sediments washing into the streams from such a steep slope make of only soil with no foliage to hold back the soil. This is why it makes sense for Herbert Run, coincidently to have a slower rate of erosion from its visible shallower slopes made of mostly foliage because by having all of that plant life, the soil is held into place more so, and thus eroding at a slower pace, so there is no visible turbidity. The phosphates have a similar display as the turbidity results since there are barely any traces of phosphates in either stream. Each stream site has 0 ppm of phosphate, except for site 2 of Herbert Run which has 0.2 ppm. Perhaps this shows that phosphate from fertilizers have no real current effect on the run-off going into the water (Simbio Software, “Nutrient Pollution”). The nitrogen levels, however, are more prominent in each stream. The Common’s stream had 1.5 ppm of nitrates at site 1 and 3 ppm of nitrates at site 2. Both sites at Herbert Run had 1.5 ppm of nitrates present in each tested area of erosion. These results in correlation to the phosphate levels show that the only site able to support ample homeostasis for life to thrive other than phytoplankton and zooplankton is site 2 of Herbert Run, seeing as how it is the only one with some trace of both phosphate and nitrate. The other sites do not appear to be able to support life since they only have traces of nitrates (Simbio Software, “Nutrient Pollution”). To have a balanced level there needs to be traces of both chemicals. On a positive note, site 2 of Herbert Run does not appear to have too drastic a difference between the two chemical levels which adds to its ability to maintain a homeostasis. Too much nitrogen also results in a lower DO level, which is apparent in the Common’s stream: site 2, and, therefore; lack of life (Perlman, 2010). After analyzing the overall results, we can accept our hypothesis. Although our hypothesis was rather basic and generalized, it did provide an ample foundation for our experiment. The results have revealed a difference between each stream in comparison to not only their own erosion between both sites, but also compared to each stream’s erosion as a whole. However, our prediction would be rejected since the data supported only part of the prediction. The results were rather off-balanced in comparison to the researched ideas from which the predictions were made. Overall, the results were half what was predicted and half unpredicted, so due to that incorrectly predicted half, thus is the reasoning that our prediction can be declared as rejected. As for the error analysis of our experiment, there were several factors that could have been conducted in a better fashion. First of all, as a precursor, the nitrates and phosphates were tested the next week due to lack of time to finish. The samples were kept in the lab refrigerator over the weekend and that may or may not have any effect on the results of those two tests. Again, with the nitrate and phosphate test, their color had to be judged by holding the sample next to another colored-water. Perhaps the judgment was askew by the group member doing the test concerning color definition due to her saying that their view of color may not have been the best match for deciding the results. Also there was the fact that some of the tools used while testing the water quality of our samples might have been faulty. For instance, the tool used to measure the pH, when put into distilled water to check its accuracy, said that the water was 8.4, which is 1.4 higher than it should have been, considering distilled water should have a neutral pH of 7. Luckily, the matter was apprehended with new testing to assure the most accurate results. Another error was that due to the stated lack of time, there were four tests being conducted at once, to try and conserve as much time as possible, so due to the possible overwhelming haste, the water samples may have been mixed up during the testing. However, all samples still received the same proper testing throughout each test performed. Last but not least, when the remaining two tests were conducted the next week, again, due to lack of time, some of the tests were cut short on proper time meant for the results to appear. For instance, instead of waiting 5 minutes between adding each acid, that time frame was cut down to 2-3 minutes in between. This may have had a major effect on the results of the nitrates and phosphates. If this experiment were to be conducted again, there would be several key factors that would need to be added or changed to allow more possible variation in data, thus providing better results in the end, as a whole. First, there should definitely be a more substantial amount of samples actually being collected. Instead of testing two sites for two rivers, why not take more samples at more sites throughout each river. Or even further, you can add another stream into the equation. Maybe, you could even try testing another type of body of water. For instance, you could test the streams and a pond or lake and then compare those to one another because the type of erosion would be different for different areas, as well as, the way they affect the water quality. When testing the water samples the tests should be conducted a minimum of 3 times to ensure accuracy of the end results. Also, more test types could be added to go more in depth into each water sample. For example, you could check for fecal matter to see if the erosion has any effect on the life-forms in that area, which would then be in correlation to the DO level and nitrate and phosphate concentration, that factor, as well, into the topic of that area’s residing life-forms. In conclusion, it appears that the rate of erosion does, in fact, affect the quality of the water. The faster the rate of erosion and the more erosion there is, the greater the sediment and nitrate levels and the lower the phosphate, pH and DO levels. ________________________________________ Bibliography

Atkins, W. A. (2003). Erosion and Sedimentation. Retrieved from http://www.highbeam.com/doc/1G2-3409400112.html

Cooke, Ken. “Dissolved Oxygen: Why Dissolved Oxygen is so Important.” KY Water Watch. 2010. Retrieved from http://www.state.ky.us/nrepc/water/wcpdo.htm

“Interpretive Point #8.” CERA Guide. Conservation and Environmental Research Areas. 1997. Retrieved from http://www.umbc.edu/cera/marker8.html

Munn, Mark. (2007). Effects of Nutrient Enrichment on Stream Ecosystems. Retrieved from http://wa.water.usgs.gov/neet/index.html

“Nutrient Pollution.” Simbio Virtual Labs. Simbiotic Software, 2009. April 22, 2010.

Readel, K. 2010. “Chemical Analysis of Water Samples.” Science 100. University of MD, Baltimore County, Spring 2010. Baltimore, MD.

Readel, K. 2010. “Science 100 Group Project.” Science 100. University of MD, Baltimore County, Spring 2010. Baltimore, MD.

Perlman, Howard. (2010). The effects of urbanization and agriculture on water quality: Nitrogen. Retrieved from http://ga.water.usgs.gov/edu/urbannitrogen.html

