Furnace Brook Lab Report

Furnace Brook Investigation

Introduction: This lab will investigate how healthy the water is in different locations in Furnace Brook. To do this, the temperature, pH level, and turbidity will be taken at each location, along with a count of the macroinvertebrates living in that area. This will help to determine how polluted the water is, because certain macroinvertebrates can only live in water with a certain level of pollution.

Research Question: Is the water quality near the Corcoran parking lot better than the water quality near the Corcoran park?

Hypothesis: The water quality in the Corcoran park will be better than the water quality in the Corcoran parking lot.

Variable Identification:

Controlled variable	Method to control the variable
Amount of sunlight	All data was taken from shady locations
Depth measurement	Depths were recorded carefully

Experimental Setup: The experiment was performed at two locations, under the bridge by the Corcoran parking lot and the bridge in the Corcoran park. The materials used were a Secchi disk,  two test tubes with a pH Wide Range TesTab and two Dissolved Oxygen TesTabs, a thermometer, meter stick, sampling container and a kick net.


Procedure:

1.      Pick a location in the stream. Record latitude and longitude.

2.      Observe the environment around your location. Record anything you notice, including water clarity, algae covering, amount of sun, etc.

3.      Measure the width of the stream and record. Divide into six equidistant locations and measure the depth of each. Record.

4.      Measure out a 40 ft section of the stream. Drop a ping pong ball into the water and record how long it takes to travel the 40 ft. Do this five times and find the average float time.

5.      Calculate stream velocity by dividing 40 feet by the average flow time.

6.      Collect some water in a small tube and put in one pH tablet. Invert tube for 4 minutes and use reference sheet to compare color. pH level will be determined by what color the water turned.

7.      Submerge another small tube into a water sample. Carefully remove the tube and drop in 2 dissolved oxygen tablets. Water will overflow. Screw cap on, making sure no bubbles are present, and invert tube for about 4 minutes. Wait 5 minutes for a color to develop, then determine DO level by comparing colors with the chart.

8.      Place net in stream with a rock at the base, one person holding it. Another goes upstream and disrupts the stream bed, sending mud and organisms into the water. Catch any macroinvertebrates with the kicknet and place in sampling container with water. Count, then return organisms to the creek.

Data:
Diversity Index of Location A

Bug species	Number	n(n-1)
Leeech	6	5(6) = 30
Scud	3	2(3) = 6
Hemiptera	1	0(1) = 0
Total	9(10) = 90	36

Diversity index = 90 / 36 = 2.5

Diversity Index of Location B

Bug Species	Number	n(n-1)
Caddisfly larva	3	2(3) = 6
Stonefly nymph	2	1(2) = 2
Scud	2	1(2) = 2
Total	6(7) = 42	10

Diversity index = 42/10 = 4.2

	pH level	turbidity	Temperature (°c)
Location A	8	0	16°
Location B	8	0	10°

Diversity index = 42/10 = 4.2


Results:


Discussion: Location A had many macroinvertebartes living there that were fairly resistant to water pollution. Leeches, scuds, and hemiptera can all survive in pollution, so there is nothing to support the fact that the water in this area was clean. In location B, very different macroinvertebrates were found: caddisfly larva and stonefly nymphs along with scuds, also found in the first location. However, caddisfly larva and stonefly nymphs are not resistant to pollution at all. They wouldn’t be able to survive in this location if there was any trace of pollution. This shows that location B was very clean. Location B also had a much higher diversity index than location A; 4.5, instead of 2.5 in the first one. This is due to the fact that there was a much more even number of each species in the second location. Each location had 3 different individual species, but the second location has either 2 or 3 of each, while the first ranged from 1 to 6.  The more even the populations are, the better diversity a place is said to have. Both locations had the same pH level and turbidity, but overall, location B has a better water quality.

Evaluation: This investigation was carried out on two different days on two different weeks. On one day, the day location A was tested, it had been sunny the previous week. The next day of testing, location B was tested. It had been very rainy that previous week. The rain may have had an effect on the water quality that would not have been like that had the conditions been the same as when the data for A was taken. This could be improved by taking the data for both locations on the same day. This investigation could be improved by taking data on each location more than once. By only doing it once, something could have been missed. Human error also could have played a role in any measurements taken. For example, depths, recordings for time, and taking readings on pH and DO may have been mistaken.

Conclusion: The data from this lab does not support my hypothesis that the water quality of location A is better. Location B had a better diversity index and the macroinvertebrates found indicated it had a lower pollution level.

References:
Topographic Map of Elmwood Park. Digital image. Mytopo.com. MyTopo, n.d. Web. 8 Oct. 2015.

Wilsey, Brian J., and Catherine Potvin. "BIODIVERSITY AND ECOSYSTEM FUNCTIONING: IMPORTANCE OF SPECIES EVENNESS IN AN OLD FIELD." Ecological Society of America. Ecological Society of America, Apr. 2000. Web. 08 Oct. 2015.