GEOS 101 Research Project ABCE

Sediment data was analyzed for heavy metal concentrations on two axes: vertically, in the core of Paramecium Pond, and spatially, in different important locations in the pond system. Distinct variations were found for different metals, for different locations, and at different depths. In the sediment cores, consistently greater metal concentrations were found in the top 50 centimeters of sediment than the bottom, suggesting that the metals may be recently deposited. Spatially, analyses imply that Paintshop Pond is still contributing heavy metals to Paramecium Pond, as well as runoff. In future work, turning this into a long-term sediment study would be highly beneficial, especially to investigate seasonal differences. We also suggest a more nuanced depth core study by analyzing samples of much smaller intervals—perhaps every five to 10 centimeters instead of 50. Taking depth cores in more locations of the pond to improve accuracy would be prudent as well.

Different heavy metals showed variable concentrations both throughout the pond system and into the pond’s core. The different trends suggest that these metals were likely deposited from different sources and through different processes. Vertical Differences Concentration of heavy metals at 0-50 cm is higher on average than 50-100 cm Could signify a change in source, such as lead wearing off of pipes or erosion changing runoff patterns Manganese and Iron Higher concentration at silver thread source shows these metals may be externally sourced and cannot travel farther downstream High levels of manganese (above 0.05 mg/L) can cause a bad taste in water which may discourage animals from using Paramecium Pond as a drinking source Zinc, Copper, Chromium Concentration also higher at silver thread source, trends diverge in rest of system Could be product of runoff or specifically from college road Likely sourced from Paintshop Pond Paintshop Pond is c...

Acknowledgements: https://pdfs.semanticscholar.org/7aac/d6905954c14cb81b3dae13bc514076e66b44.pdf http://www.sciencedirect.com/science/article/pii/S0304389410001652 https://tools.thermofisher.com/content/sfs/brochures/NitonMudLoggingAppNote.pdf https://www.lenntech.com/aquatic/metals.htm

Analysis The Graph shows that the mean concentration for each heavy metal considered in the graph is greater when the depth is less. Therefore, at a depth of 0-50 cm the concentration is, on average, higher. This makes sense because the metals enter the pond as a result of external, surrounding factors. They may continue to float at the top of the pond before possibly going off into the silver stream. This results in the surface of the pond to have a greater concentration of the heavy metal sediments. Additionally, the water goes through the outer drain and ultimately enters Lake Waban. This could mean that the sediment at the bottom of Paramecium Pond could travel towards Lake Waban. This would essentially decrease the concentration of the heavy metals at a greater depths.

Acknowledgements The authors would like to thank Dan Brabander and Kathleen Gilbert for their tireless assistance and instruction, Jordan Tynes for providing impressive drone images of the pond system, and former GEOS 101 students for contributing useful data from prior years.

Intro (the spacing got messed up in the last paragraph lemme know if you need me to fix it) Paramecium Pond is a man-made system that has been integrated into its natural surroundings over the course of many decades. Built as an addition to the botanic gardens in 1931, the pond’s purpose is purely aesthetic. The pond is fed by the silver stream, a brook which itself is fed by drinking water pumped through a well. The pond drains through a grate on the southwestern end of the pond to Lake Waban. Paramecium Pond has been dredged twice in its history, due to an excess of deposited sediment--once in 1975 and once in 1995. The current depth of the pond floor ranges from <1 foot to around 5 feet deep. Due to its urban location, the pond is subject to runoff and pollutants from within its ecological system that might not be found in a more natural setting. Heavy metals such as zinc, copper, chromium, manganese, and lead can accumulate at the surface of streets and roofs. These and ot...

Methods Grab Samples Samples from the middle of the pond were taken by boat using a ponar-type grab sampler and samples from the edge were taken using a peat corer or by hand. These samples were then plated in petri dishes and left to dry in a furnace. Dry samples were ground using a (name of instrument) and divided into samples to be analyzed via XRF analysis. Core Samples Core samples were taken by students in earlier years by using a Russian peat corer. The peat corer is pushed into the sediment and twisted to collect a cylindrical core, which is then removed, photographed, measured, sliced into sections, and left to dry. Dry samples were ground using a mixer mill and prepared for XRF analysis. X-Ray Fluorescence (XRF) Analysis Methods Photons are shot at sample, causing inner-shell electrons to be ejected. Outer-shell electrons fill vacancy and emit more photons. Each element has a different signature, which is picked up by the XRF detector. XRF Analysis can show both ...

Figure y: concentration of iron (Fe) analyzed in sediment from the Paramecium Pond system. Iron concentration is highest at the source of the stream and fairly constant through the rest of the system.

Analysis Different heavy metals showed variable concentrations both throughout the pond system and into the pond’s core. The different trends suggest that these metals were likely deposited from different sources and through different processes. Manganese and Iron Higher concentration at Silver Thread source shows these metals may be externally sourced and cannot travel farther downstream High levels of manganese (above 0.05 mg/L) can cause a bad taste in water which may discourage animals from using Paramecium Pond as a drinking source Zinc, Copper, Chromium Concentration also higher at Silver Thread source, trends diverge in rest of system Could be product of runoff or specifically from college road Likely sourced from Paintshop Pond Paintshop Pond is contaminated with toxins and heavy metals due to dumping of paint factory waste from 1848-1920 Likeliest source of zinc , copper , and chromium in Paramecium Pond Heavy metals found in the pond an...

The graph compares the mean concentration of lead (Pb), chromium (Cr), zinc (Zn), and manganese (Mn) in parts per million. The graph analyzes the core sediments from the same coordinate location, but at two different depths. It analyzes the concentration levels of these heavy metals at the two different depths. 

Figure x: concentration of lead (Pb), zinc (Zn), copper (Cu), manganese (Mn) and chromium (Cr) analyzed in sediment from the Paramecium Pond system. Data from the Pond Edge and Pond Center are average values from several sample locations, while the stream values are single data points. Note that in general, Mn concentration decreases through the system; Zn decreases through the stream, but is more present in the pond; and Pb has a higher concentration in the pond than in the stream. Also note that Cu and Cr are not present in the stream at detectable levels.

here is the link to my google doc again so you don't have to scroll for it -Ellie

Metals such as Zinc, Chromium, Manganese and Lead are introduced to various aquatic systems, like the Paramecium Pond.  The Paramecium Pond is part of this system in an urban setting. Therefore, large amounts of pollutants accumulate at the surface of streets and roofs. Ultimately, they are carried towards and end up being part of the pond. With regards to these sediment, more is found closer to the inlet compared to the outlet.  The metals that we have selected to look at for this project are Zinc, Chromium, Lead, and Manganese. These are all considered heavy metals (because they all have an atomic number great than 20). According to a study done on ‘ Heavy metal concentrations and toxicity in water and sediment from stormwater ponds and sedimentation tanks,’ the concentration of metals were the highest in ponds. This is important when considering how these metals affect the sediment in Paramecium Pond. Looking at the actual results, it is surprising to see Manganese ha...

Interestingly, different heavy metals showed variable concentrations both throughout the pond system and into the pond’s core. Not only that, but different metals show different trends, suggesting that they were deposited into the sediment from different sources, and transit the system differently. Manganese and iron show a similar trend: each were found in their highest concentration at the stream’s source, and at similar concentrations through the remainder of the system. While both elements are natural components of soil, the fact that they have their highest concentration at the stream’s source suggests that they may be input to the stream externally—perhaps through runoff—and deposited at the source, and cannot travel further down the stream. Like manganese and iron, zinc concentrations are highest at the stream source, but the trends diverge in the rest of the system. Zinc has much lower concentrations through the rest of the stream, but concentrations rise again within the pond....

Figure x: concentration of lead (Pb), zinc (Zn), copper (Cu), manganese (Mn) and chromium (Cr) analyzed in sediment from the Paramecium Pond system. Data from the Pond Edge and Pond Center are average values from several sample locations, while the stream values are single data points.

Kathy Dan Wellesley College Department of Geosciences Fall 2016 GEOS 101 class (for collecting a lot of our data) comment any additions!

Hi all, So this post has five different graphs of the following elements: Zinc, Chromium, Manganese, Lead and Iron. It uses the sediment core data for these elements and compares the Niton 0-50 and the Niton 50-100 sediment core data for each of these elements. Additionally, it compares the mean of the Niton 0-50 and the Niton 50-100 for each element. That being said, I have to edit these further to understand what the right axises will be and what more to add to the graphs and how to use them most effectively while analyzing sediments.

Hello! Here's my "money graph", and I can certainly make more, but this one raises questions that I hope we can draw conclusions about: why does Silver Thread, especially at the source, contain more manganese than the pond? Is manganese being trapped in ST sediment? Why is zinc concentration so high at the ST source, drop off in the rest of the ST, and get higher again in the pond? Where is zinc coming from? Chromium and copper are only present at detectable levels in the pond and not in the stream, which is interesting-- why? And finally, why are lead concentrations higher in the pond than in the silver thread? So many good questions to be explored!

Brainstorming focus!! next week: see posters, get ideas, also we should look at old posters maybe What do? we should ask Kathy for help on monday and then brainstorm some more focus on sediment, obviously depths of core samples silver thread vs. pond compare presence of elements/heavy metals interested in presenting the pond as a system initially

Here is what I have written so far for our poster in a google doc. I will add to/modify it as we have more text to add and a clearer idea of our goals.