Posts

conclusion/future

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.
Post a Comment
Read more

revised 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. 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...
Post a Comment
Read more

Acknowledgements:

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
Post a Comment
Read more

Analysis

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.
Post a Comment
Read more

acknowledgements (thoughts? :^) )

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.
Post a Comment
Read more

Intro

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...
1 comment
Read more

Methods (can be turned into bulletpoints if too wordy)

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 ...
Post a Comment
Read more