Lauren Ho 10.31.2017 AP Environmental Science Alan Mcintyre
Campus Pond Assessment
- General purpose
The general purpose of this lab and field work was to study Proctor’s campus pond and to look at the general health of it. We were taking into account the biotic and abiotic aspects of the pond to determine its health, looking specifically at the diversity of the pond as it’s a huge determinant of the ponds’ health. Knowing and understanding the health of the pond is important, because it informs us of the overall health of our campus ecosystem, which ultimately has a large impact on us. It was also a very effective way for us to continue our in class study of species interactions and community ecology. Because this was the tenth and final year of a ten year APES class generation study, we were able to pull up past data and look at it in comparison to this year’s data, and identify trends throughout the years. To ensure more accurate data collection, we were split into groups to study different parts of the pond as opposed to only taking samples from one location on the pond. There were six sites in total and our class groups covered five of them. There were also other APES classes doing the same project, so we collected raw data and calculated averages between sites and classes.
Variables:
Controlled - Location(s) of data collection, method of data collection,
Independent - The year and date of data collection
Dependent - Abiotic (Temperature, turbidity, pH levels, nitrogen, dissolved oxygen, phosphate levels) and biotic (number of species and species diversity) data of pond
Hypothesis:
I predict that the campus pond is not extremely healthy, but is not extremely unhealthy. I would guess that it is unhealthier than it was in the past, because of the increase in air pollution around Proctor’s campus as well as the source/inflow of the water. Also, the Proctor pond isn’t something that is greatly cared for, parts of it are becoming very overgrown and it lets off a not-so-nice smell, as well as the fact that the water is not very clear and it looks quite murky. However, there isn’t any specific reason for the pond to be very unhealthy, as in people don’t litter in it or do anything to it. It all just grows and ages as it naturally would. If the pond is healthy, I would expect to see a high diversity index, a neutral pH of about 6-7, low phosphate and nitrate levels, and high dissolved oxygen levels.
2) Materials Used:
Material
|
Quantity
|
Magnifying glass
|
1
|
D-Ring Net
|
1
|
Pipette
|
1
|
Tupperware container with 3 sections
|
1
|
Container or bin
|
1
|
pH Level test set
|
1
|
Phosphate test set
|
2
|
Turbidity test
|
1
|
Temperature & dissolved oxygen reader
|
1
|
Nitrogen test
|
1
|
Species identification sheet
|
1
|
Digital thermometer
|
1
|
Dissolved O2 measurement
|
N/A
|
3) Method of Data Collection:
Biotic data collection (photos by Lauren Ho)
- Each group went to each site with materials (listed above) to explore abiotic and biotic features of the pond
- We took the larger tub/bucket and filled it a quarter full with water from the pond, making sure the the water is fairly clear of dirt, leaves, twigs, etc.
- Taking the D-ring net, One person used the net and swept the bottom of the pond 3-5 times (depends) through the water, being sure to reach all the way to the bottom
- After the fifth sweep, scoop the contents of the net (but don’t dig into the dirt) into the large collection tub–you may have to get your hands dirty in order to get all the contents out of the net!
- Using your hands or the spoons and pipette, remove all of the abiotic features that are in the tub (i.e. leaves, twigs, trash)
- Sift through and locate all of the living specimens into the smaller container with three compartments (add clear pond water so that the creatures stay alive) Identify the specimen using the ID guide and magnifying glass. Keep a tally of the number of species found per test, but do not combine the tallies of multiple tests.
Abiotic data collection method
- pH test
- Fill test tube to 10ml
- Put little tablet in water
- Shake tube until tablet is dissolved
- Compare color to chart
- Phosphate Test
- Fill test tube to 5ml
- Put tablet in
- Shake until tablet is dissolved
- Wait 5 minutes
- Compare color to chart
- Turbidity test
- Fill tube with water
- Put in the middle and compare the clarity to the examples on the card
- Temperature/Dissolved oxygen
- Put the rod in the water and slowly circled it
- waited for the numbers to adjust from the air
4) General narrative of sites 
Site 3: Matilda, Sydney and I were stationed at site 3, which is located on the corner of the pond, between sites 5 and 2. It’s located nearest to the health centre. There is a small downhill grass slope that leads down onto the sandy, beach area. It’s on the far end of the stone wall that runs along the edge of the pond, with site 5 being on the opposite end. This site is known as the ‘beach site’, because it has an actual mini bank of sand. Over the years, this site has become more and more overgrown with weeds and tall grasses, and has much less sand space visible than a few years ago. We had to put on rain boots and actually go and walk a few inches into the pond, walking through the tall brown weeds/grasses to actually get to where the water was deep enough to scoop with our net. I was absent the first two days, but Matilda and Sydney still collected data. According to recorded data (as I was not present), the first day was October 14th, 2017 at around 8:30am - the average air temperature was 47ºF, with the lowest and highest recordings being a minimum of 33ºF and a maximum of 61ºF, and it was a relatively foggy morning but there was no precipitation. Again, according to recorded data (I was not present), the second day of data collection on October 16th, 2017 at around 10:35am had an average air temperature of 62ºF, with the lowest and highest recordings being a minimum of 53ºF and a maximum of 70ºF, and it was slightly warmer and sunnier day, with a slight breeze. The third and final day of data collection, which I was present for and actively engaged in, was October 17th, 2017 at around 2:05pm, with the average air temperature being 52ºF, with the lowest and highest recordings being a minimum 39ºF and a maximum 66ºF. On this day, the weather was slightly cloudy, but also clear, and was also quite windy. At our particular site, there were a lot of dead weeds and leaves, as well as dirt and twigs from the bottom of the pond. Not to mention, because we were on the ‘beach’, there were a lot of sand, which made it easy for the living creatures to hide and camouflage themselves, making it particularly hard for us to locate, catch and identify them.
Site 1: This site is one of the two inflows of the pond. It’s located at the corner opposite to site 3, and is between site 2 and site 4. Site 1’s inflow comes from and follows the path of drains between ice rink and field house, outside the dining hall, the pond behind the ice rink and in front of the library
Site 2: This site is the other of the two inflows. It’s located on the corner opposite to site 5, and it is between site 3 and site 1. The inflow from site 2 comes from turf and field drainage, and from the underground river that leads from the woods near the ice rink to the softball field
Site 4: This site is located by the lamp post right between site 1 and site 5. It’s located in the middle of the edge of the pond, closest to Shirley hall. Site 4 is neither an inflow or an outflow site.
Site 5: This site is where the outflow of the pond is. It’s located on the corner opposite to site 2, and it’s between site 3 and site 4. It’s on the end of the mini stone wall, with site 3 on the opposite end, the side closest to Shirley hall. The outflow leads out to the Merrimack river, and goes through and follows that path, and ultimately ends up in the ocean.
5) Data Tables
Abiotic Data:
Water Temperature
2007
|
2008
|
2009
|
2010
|
2011
|
2012
|
2013
|
2014
|
2015
|
2016
|
2017
|
Avg. (ºF)
| |
Avg. Water Temp (ºF)
|
52.1
|
52.1
|
N/A
|
53.1
|
N/A
|
54.3
|
55.6
|
54.4
|
50.5
|
47.0
|
56.6
|
52.9
|
Site 1
|
52.0
|
52.0
|
N/A
|
53.0
|
N/A
|
53.0
|
53.7
|
53.7
|
52.4
|
49.7
|
56.6
|
52.9
|
Site 2
|
52.4
|
52.4
|
N/A
|
53.4
|
N/A
|
53.7
|
57.2
|
56.8
|
49.5
|
44.2
|
58.5
|
53.1
|
Site 3
|
50.3
|
50.3
|
N/A
|
53.3
|
N/A
|
N/A
|
57.3
|
54.8
|
51.1
|
N/A
|
56.9
|
53.4
|
Site 4
|
52.5
|
52.5
|
N/A
|
52.5
|
N/A
|
53.6
|
62.5
|
54.0
|
49.2
|
47.8
|
58.2
|
53.6
|
Site 5
|
52.3
|
52.3
|
N/A
|
53.3
|
N/A
|
56.8
|
56.3
|
56.0
|
49.3
|
46.7
|
57.2
|
53.4
|
Site 6
|
53.1
|
53.0
|
N/A
|
N/A
|
N/A
|
N/A
|
50.6
|
51.4
|
51.6
|
N/A
|
52.4
|
52.0
|
pH Levels
2007
|
2008
|
2009
|
2010
|
2011
|
2012
|
2013
|
2014
|
2015
|
2016
|
2017
|
Avg.
| |
Site 1
|
7.0
|
7.0
|
N/A
|
7.0
|
N/A
|
6.8
|
8
|
6.44
|
6.5
|
7.00
|
7.07
|
6.98
|
Site 2
|
7.2
|
6.8
|
N/A
|
6.8
|
N/A
|
6.6
|
7
|
5.85
|
6.17
|
6.67
|
6.37
|
6.61
|
Site 3
|
6.2
|
6.8
|
N/A
|
6.8
|
N/A
|
N/A
|
7
|
6.29
|
6.23
|
N/A
|
6.67
|
6.57
|
Site 4
|
6.8
|
7.5
|
N/A
|
7.0
|
N/A
|
6.6
|
7.5
|
6.25
|
6.62
|
6.67
|
6.75
|
6.85
|
Site 5
|
6.9
|
7.3
|
N/A
|
6.8
|
N/A
|
6.5
|
7
|
6.18
|
6.705
|
6.67
|
6.92
|
6.775
|
Site 6
|
6.5
|
6.8
|
N/A
|
N/A
|
N/A
|
N/A
|
7
|
5.86
|
6.275
|
N/A
|
6.30
|
6.46
|
Avg PH
|
6.77
|
7.03
|
N/A
|
6.88
|
N/A
|
6.625
|
7.25
|
6.145
|
6.42
|
6.75
|
6.68
|
6.71
|
Turbidity Levels
Year
|
2007
|
2008
|
2009
|
2010
|
2011
|
2012
|
2013
|
2014
|
2015
|
2016
|
2017
|
Average (JTU)
|
0.2
|
0.2
|
N/A
|
2
|
N/A
|
0
|
20
|
4.85
|
6.87
|
5.3
|
13.3
|
Phosphate Levels
Year
|
2007
|
2008
|
2009
|
2010
|
2011
|
2012
|
2013
|
2014
|
2015
|
2016
|
2017
|
Average
(PPM)
|
2.2
|
4
|
N/A
|
3.5
|
N/A
|
0.43
|
0.4
|
1.05
|
N/A
|
N/A
|
0.97
|
Nitrate Levels
Year
|
2007
|
2008
|
2009
|
2010
|
2011
|
2012
|
2013
|
2014
|
2015
|
2016
|
2017
|
Average (PPM)
|
0.2
|
0
|
N/A
|
0
|
N/A
|
0
|
0
|
0.56
|
N/A
|
N/A
|
0
|
Dissolved Oxygen Levels
Year
|
2007
|
2008
|
2009
|
2010
|
2011
|
2012
|
2013
|
2014
|
2015
|
2016
|
2017
|
Average DO Level (mg/L)
|
2.5
|
1.67
|
N/A
|
1.6
|
N/A
|
1.5
|
N/A
|
6.2-7.9
|
6.65
|
8.3
|
1.39
|
Biotic Data:
Raw Species Data 2017 
Calculated Diversity Index
Year
|
2007
|
2008
|
2009
|
2010
|
2011
|
2012
|
2013
|
2014
|
2015
|
2016
|
2017
|
Average
|
19.3
|
15.4
|
0.74
|
11.7
|
N/A
|
7.26
|
12.2
|
7.1
|
6.3
|
6.3
|
7.4
|
6) Analysis of data trends
We used “Simpson’s Diversity Index” to calculate and put a number on the diversity of the pond. The equation for this is
Diversity index is described as “a quantitative measure that reflects how many different types (such as species) there are in a dataset (a community), and simultaneously takes into account how evenly the basic entities (such as individuals) are distributed among those types.” After collecting and calculating the data of all classes, the determined diversity index this year came out to be 7.4, a number considered to be slightly above average in comparison to more recent years, but significantly lower than numbers calculated at the start of the ten year study. The diversity each year had been decreasing rapidly, but in recent years, the trend is seemingly levelling out with a few fluctuations here and there. There were other factors playing a role in the diversity of the pond. For example, there was a massive decrease in diversity in 2012, which was when the turf went in. However, there are currently no real explanations as to why the diversity decreased so quickly from 2007 to 2011. Despite that, there are many reasons why it potentially could have been lower one year compared to another. In 2009, the data from this year isn’t really considered in this lab, because the weather that year was so cold that there was already a layer of thick snow on the ground when they tried the experiment. This meant they weren’t even able to find 100 individual critters, and found a ridiculously small number of around 12 different species. Other factors could have been that not all sites were studied. For example in 2010, five sites were studied, but in 2012, only four sites were studied. A huge impact was in 2012 when the new turf was put in beside the pond, which caused us to see a sudden decrease in diversity. It then when back up in 2013 and showed resilience and rebuilt itself after the exterior disruption. This could make the data less accurate. Because diversity is a huge indicator as to whether the pond is healthy or not, does the fact that the diversity index is decreasing mean the pond health is as well? Potential reasons for this could be interspecific and intraspecific competition. Extinction within species and species coexistence both lead to a lower diversity index.
Diversity index is described as “a quantitative measure that reflects how many different types (such as species) there are in a dataset (a community), and simultaneously takes into account how evenly the basic entities (such as individuals) are distributed among those types.” After collecting and calculating the data of all classes, the determined diversity index this year came out to be 7.4, a number considered to be slightly above average in comparison to more recent years, but significantly lower than numbers calculated at the start of the ten year study. The diversity each year had been decreasing rapidly, but in recent years, the trend is seemingly levelling out with a few fluctuations here and there. There were other factors playing a role in the diversity of the pond. For example, there was a massive decrease in diversity in 2012, which was when the turf went in. However, there are currently no real explanations as to why the diversity decreased so quickly from 2007 to 2011. Despite that, there are many reasons why it potentially could have been lower one year compared to another. In 2009, the data from this year isn’t really considered in this lab, because the weather that year was so cold that there was already a layer of thick snow on the ground when they tried the experiment. This meant they weren’t even able to find 100 individual critters, and found a ridiculously small number of around 12 different species. Other factors could have been that not all sites were studied. For example in 2010, five sites were studied, but in 2012, only four sites were studied. A huge impact was in 2012 when the new turf was put in beside the pond, which caused us to see a sudden decrease in diversity. It then when back up in 2013 and showed resilience and rebuilt itself after the exterior disruption. This could make the data less accurate. Because diversity is a huge indicator as to whether the pond is healthy or not, does the fact that the diversity index is decreasing mean the pond health is as well? Potential reasons for this could be interspecific and intraspecific competition. Extinction within species and species coexistence both lead to a lower diversity index.
The turbidity is increasing quite rapidly, which in simpler terms, means the water is becoming cloudier and cloudier each year. There are multiple factors that affect the turbidity of a body of water. What turbidity is is “suspended solids comprised of organic and inorganic materials such as sediment, algae and other contaminants”. Keeping in mind that the water from the pond, other than rainfall, flows in from outside sources, there could be pollution from the source of the water, which would cause higher turbidity levels. High turbidity is mostly seen as a bad thing where bacteria, viruses and parasites can attach themselves to the increased number of suspended particles in the water. To give an idea of comparison, the water in the pond is definitely not healthy enough or clean enough to drink, as drinking water should not have a higher turbidity than 5 NTU.
Nitrate levels have remained quite constant - continuing to have very low numbers, as have average water temperatures, which have continued its trend in the low to mid 50’s. The pH has also remained relatively constant throughout the years, this is expected but it would be a cause of concern if it wasn’t. The pH levels have remained in the 6-7 region, which is quite neutral. This is desirable, because it prevents drastic changes to life in the pond due to death or mutation. If the pond suddenly becomes more acidic or more alkaline, it can and will most likely be fatal to many of the creatures and their species in the pond.
Dissolved oxygen levels were quite low in the earlier years, then they spiked, but this year dropped back down drastically. Dissolved oxygen is “the amount of gaseous oxygen (O2) dissolved in the water. It enters the water by direct absorption from the atmosphere, by rapid movement, or as a waste product of plant photosynthesis. Water temperature and the volume of moving water can affect dissolved oxygen levels”. It’s quite strange that the dissolved oxygen levels increased so significantly so fast and only for a few years, before dropping from an 8.3 to a 1.39 in just a year. Dissolved oxygen levels are affected by diffusion and aeration, photosynthesis, respiration and decomposition. Low dissolved oxygen levels can be caused by excessive algae or plant growth, which has been increasing in our pond, and this excessive growth is caused by the phosphate levels. Especially at site 3, the proctor beach has been progressively becoming more and more overgrown with plants and algae. As mentioned, water temperature plays a role, but it has been quite consistent throughout the years.
Average phosphate levels have been quite staggered, but do seem to be showing a downhill trend. There was no phosphate level data collected in the last few years, however, the pond is looking slightly more unhealthy than it did in 2012-2013. It is looking quite a bit more healthy than it did at the start of the study, but it is not currently at the healthiest point that it has been in the past. It’s encouraging and happy for us to see that the phosphate levels are decreasing, which means the pond is becoming healthier.
Looking at the biotic data from this year and previous years, the major indicator species (biological species that defines a trait or characteristic of the environment) that stood out were mayflies, caddisflies, and stoneflies. Their populations in the past years are listed in the table below:
2007
|
2008
|
2009
|
2010
|
2011
|
2012
|
2013
|
2014
|
2015
|
2016
|
2017
| |
Mayfly
|
12
|
5
|
N/A
|
11
|
N/A
|
9
|
30
|
72
|
N/A
|
27
|
24
|
Caddisfly
|
1
|
1
|
N/A
|
1
|
N/A
|
3
|
11
|
5
|
N/A
|
N/A
|
2
|
Stonefly
|
5
|
2
|
N/A
|
1
|
N/A
|
1
|
22
|
6
|
N/A
|
N/A
|
6
|
From the table above, it can be seen that the numbers for all three species increased greatly in the years 2013-2014. This could have been influenced by some factor, potentially ‘species coexistence’ which allowed the populations of these three species keep their numbers increasing or constant, other than the 2013-2014 spike.
There was definitely room for error in this data collection process. One of the most prominent is the lack of professionalism, detail, precision and time. Because we only had one class block to gather data each session, we didn’t have a whole lot of time to pick out every single creature in the bucket. Also, we were completely ‘eyeballing’ almost all of the data we collected, which leaves a margin for error, because the eyeball could interpret it differently. It’s very likely that we didn’t manage to see every single creature in the bucket. Also, when there was a very large number of a particular organism, for example the Copepod, we had to make educated guesses as to how many there were, we didn’t count them all specifically. Furthermore, although we did study five sites around the pond, all our sites were along the edge of the pond, and the majority of the pond was not studied. There’s a fair chance most of the creatures of the pond were closer to the middle, where we couldn’t reach and study. Thinking about it relative to the size of the whole pond, we actually covered very little of the pond. Furthermore, there was a lot of missing data that was either recorded incorrectly or not recorded. In some years, only a few locations were studied, and abiotic data wasn’t gathered from all of them, whereas in other years there was more data to find an average from. As noticeable in all the data tables, there are a lot of gaps in the data.
7) Conclusion
After analyzing the biotic and abiotic data of the pond, the data indicates that my hypothesis was correct. The pond is not extremely healthy, but it’s also not extremely unhealthy. It has been healthier in the past, especially in the earlier years. There is a bit of conflicting data regarding the ponds health, though, for example in 2008, it had a pretty high diversity index (indicating a healthy pond), however it had a 4ppm phosphate level, which indicates an unhealthy pond. This year, there was no alarming data to cause any reason for concern. Of course, there are things that we can do/not do to help maintain the health of the pond, but at the moment, it seems to be at a stable place. The pond is showing a trend of being less healthy than at the start of the study, which is a bit upsetting, but it’s nothing too much that should be worried about.
The variables that should have remained the same have done so for the most part, but there are parts that have not, which could mean there’s a few less reliable pieces of data. For example, one of the controlled variables was the sites of data collection. While the sites did remain the same, there weren’t always people stationed at each site every year - especially site 6, the drainage site, for most classes, most years there was no one there. This means less data was collected there, and less data lacks precisions and reliability. Also, the people collecting the data were different, and we weren’t following a specific method, but instead writing up a new one each year, so it is likely that the procedure of data collection wasn’t exactly the same. It was probably generally the same, but not exactly the same. Something else that changed would be the weather. Although, the experiment was carried out around the same time each year, of course, each year is different and this could have an impact on the data collected. For example, in 2009, much of the data wasn’t used, because the weather was so cold that data just couldn’t be collected. Snow will affect the acidity and temperature, and this affects the live and diversity in the pond. Also, when it’s cold and snowing, the species will become more competitive fighting over resources, and this will affect the populations of certain species.
I really enjoyed this project, because although I unfortunately missed two lessons/days of fieldwork and data collection, I was thankfully able to be present at the third day of data collection, and I had a lot of fun catching and separating the different species and identifying them using the magnifying glass and species identification sheet. I found it a little bit hard to catch up and get right back into things after having missed two classes, but I was grateful that Sydney and Matilda were patient with me and explained to me everything that I needed to know and that was going on. The data collection itself wasn't too hard, but understanding why we needed to know things like the purpose of 'dissolved oxygen' and 'nitrate levels' was confusing for me. Digging and sifting through the leaves and twigs in the pond to location and catch tiny creatures that camouflaged themselves in the leaves was a challenge, but I was patient and had fun doing it, even though it seemed like every time I got my capturing spoon under it, it would swim away incredibly quickly and hide itself somewhere else! I was excited for this project, because I gained a better understanding of the place that I live most of the year, where I spend a lot of time. I also learned how to do collect abiotic data, and how to study the quality of water. The most complicated thing I think I learned through this was doing the calculations with “Simpson’s Diversity Index”, because I was happy that I understood it and am able to do it (because my math is just terrible), but also I think it’s a really cool skill to have to be able to calculate the diversity of a pond and determine how healthy a body of water is. Being able to know about the health of our ecosystem was really interesting for me. I'm excited for the future to become even more involved with the environment and interact more with it.
