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Watershed Assessment Analysis of Data

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Q Values Raw data values are NOT Q values. We need to convert the raw data/observations into “grades” (Q values) Post all of your group’s collected abiotic and biotic data on the board such that averages may be obtained.

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Temperature 1.Find difference between highest and lowest temperatures for the pond (∆T). Consider ALL of the collected values for each location (not just your class) 2. Use the Table 4 in your lab handout to determine the “grade”/Q value for temperature 3.The smaller the difference, the higher the Q value 4.Repeat steps 1-3 for the river

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Dissolved Oxygen To determine the Q value for D.O., we must first determine how much oxygen the water source could be expected to have at its temperature Calculate the average D.O. for the pond Use the nomogram on page 3 of your lab handout to determine the % saturation for the pond. Use AVG temp. and AVG D.O. Once you have determined % saturation for the pond, use table 1 to determine the Q value for Dissolved Oxygen If % saturation exceed 100%, you will have to extrapolate the Q value on table 1 Repeat steps 2-4 for the pond

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pH and Total Dissolved Solids 1.Use the appropriate tables (2-3) to determine the Q value for each parameter 2.Average the pH readings for the pond and use the appropriate table to find the Q value 3.Average the TDS readings for the pond and use the appropriate table to find the Q value Note: NTU = mg/L 4.Extrapolate if the average pH or TDS is between the increments on your table 5. Repeat steps 1-3 for the river 6. While low TDS/turbidity values are desired, moderate pH values are desired

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Benthic Macroinvertebrates Benthic Macroinvertebrate Q value does NOT factor into the overall abiotic Q value Unlike the abiotic Q values, a lower Q value for benthic macroinvertebrates is indicative of a healthier ecosystem High biodiversity of pollution tolerant species is indicative of an unhealthy ecosystem

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Fecal Coliform Obtain your Coliscan plate from the incubator and view under a stereoscope Count all purple and pink fecal coliform colonies on your plate. Keep a separate tally of purples alone as they represent E. coli Since you sampled 5mL of water, multiply your total # of f.c. x 20 to express as total number of fecal coliform/100mL Post your findings on the board and average the number of fecal coliform for the water source Using Chart 2 on p.7 of your lab, use the class average to calculate the Q value for fecal coliform. Make sure you obtain the results for both river and pond

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Conclusion To determine the relative health of each ecosystem (river and pond), think about its overall abiotic Q value, its benthic macroinvertebrate Q value and its fecal coliform. The last two factors should be about 1/3 rd of your consideration. Cite specific data AND Q values when supporting your decisions about the health of each ecosystem For each parameter (pH, temp, etc.) you should attempt to explain why it was healthy or unhealthy using logical reasoning. This needs to be addressed for both river and pond. You are comparing the systems but also addressing each’s individual health Include any qualitative observations in your decisions Be sure to address both confounding variables AND sources of error

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Data Presentation Data tables (2): one for abiotic Q values, one for biotic Q values Graph the Q values for 5 of the 6 values (do not graph benthic macroinvertebrates Q value as it is inverse) Bar graph format

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