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Troy Martin
Email: [email protected] Twitter: @troymartinlimno Hi! My name is Troy Martin, and I am a graduate student at Queen’s University, Kingston, ON, Canada. My research looks at how aquatic communities are impacted by different de-icing chemicals. |
De-icing chemicals such as road salt (NaCl) are the primary cause for increasing salinization and chloride in freshwater in North America1. Chloride is toxic to aquatic life and subsequently has been classified as a toxic substance by the Canadian Government2. In attempts to reduce the amount of road salt and chloride used, road de-icer alternatives have been created3,4. These include organic alternatives that add sugars and by-products to salt, and inorganic alternatives that often use a blend of a variety of chloride chemicals (NaCl, MgCl2, CaCl2, etc.).
I tested the toxicities of traditional road salt and two alternatives to zooplankton. Zooplankton are key primary consumers in lake ecosystems, transferring energy up and through the food web. They are also very sensitive to pollutants, and as such are good test subjects when assessing toxicity to freshwater environments.
I used two alternatives in my experiment. One is representative of an organic alternative, Fusion 2330. This de-icer is a blend of sodium chloride brine and beet sugars. The other is representative of an inorganic alternative, Master Melt. This de-icer is a blend of CaCl2, NaCl, and MgCl2. I tested my three de-icers in mesocosms on a gradient of 20 chloride concentrations, ranging from ~6 to ~1500 mg Cl-/L. This experiment took place at the Queen’s University Biological Station (QUBS), approximately an hour north of Kingston, ON.
Zooplankton communities were sampled at 6 weeks to see the chronic effect. The current results are below. We are still in the process of analyzing individual species responses, as well as functional and bacterial diversity changes.
I tested the toxicities of traditional road salt and two alternatives to zooplankton. Zooplankton are key primary consumers in lake ecosystems, transferring energy up and through the food web. They are also very sensitive to pollutants, and as such are good test subjects when assessing toxicity to freshwater environments.
I used two alternatives in my experiment. One is representative of an organic alternative, Fusion 2330. This de-icer is a blend of sodium chloride brine and beet sugars. The other is representative of an inorganic alternative, Master Melt. This de-icer is a blend of CaCl2, NaCl, and MgCl2. I tested my three de-icers in mesocosms on a gradient of 20 chloride concentrations, ranging from ~6 to ~1500 mg Cl-/L. This experiment took place at the Queen’s University Biological Station (QUBS), approximately an hour north of Kingston, ON.
Zooplankton communities were sampled at 6 weeks to see the chronic effect. The current results are below. We are still in the process of analyzing individual species responses, as well as functional and bacterial diversity changes.
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Figure 1. (Clockwise from top left) a) Abundance of Cladocera (/L) vs. chloride concentration (mg/L), ± 95% CI. b) Abundance of Copepods (/L) vs. chloride concentration (mg/L), ± 95% CI. c) Abundance of Nauplii (/L) vs. chloride concentration (mg/L), ± 95% CI. d) Abundance of Rotifers (/L) vs. chloride concentration (mg/L), ± 95% CI. Dashed vertical lines represent the EC50, or effective concentration where the abundance decreased by 50%. A grey line indicates there was no interaction or difference between de-icers.
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Figure 2. (Left to right) a) Species richness (/sample) vs. chloride concentration (mg/L), ± 95% CI. b) Shannon’s diversity index (/sample) vs. chloride concentration (mg/L), ± 95% CI. c) Community evenness vs. chloride concentration (mg/L), ± 95% CI. Trendline on evenness represents an effect of chloride, but no interactive effect.
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Figure 3. Chlorophyll a concentration (ug/L), as proxy for algal biomass vs. chloride concentration (mg/L) ± 95% CI.
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Please do not hesitate to reach out to me if you have more questions!
References
1. Hintz, W. D., & Relyea, R. A. (2019). A review of the species, community, and ecosystem impacts of road salt salinisation in fresh waters. Freshwater Biology, 64(6), 1081–1097. https://doi.org/10.1111/fwb.13286
2. Canadian Council of Ministers of the Environment. (2011). Canadian water quality guidelines for the protection of aquatic life: Chloride, p. 1-16. Canadian environmental quality guidelines 1999. Winnipeg: Canadian Council of Ministers of the Environment.
3. Schuler, M. S., Hintz, W. D., Jones, D. K., Lind, L. A., Mattes, B. M., Stoler, A. B., Sudol, K. A., & Relyea, R. A. (2017). How common road salts and organic additives alter freshwater food webs: in search of safer alternatives. Journal of Applied Ecology, 54(5), 1353–1361. https://doi.org/10.1111/1365-2664.12877
4. Gillis, P. L., Salerno, J., Bennett, C. J., Kudla, Y., & Smith, M. (2021). The Relative Toxicity of Road Salt Alternatives to Freshwater Mussels; Examining the Potential Risk of Eco-Friendly De-icing Products to Sensitive Aquatic Species. ACS ES&T Water, 1(7), 1628–1636. https://doi.org/10.1021/acsestwater.1c00096
References
1. Hintz, W. D., & Relyea, R. A. (2019). A review of the species, community, and ecosystem impacts of road salt salinisation in fresh waters. Freshwater Biology, 64(6), 1081–1097. https://doi.org/10.1111/fwb.13286
2. Canadian Council of Ministers of the Environment. (2011). Canadian water quality guidelines for the protection of aquatic life: Chloride, p. 1-16. Canadian environmental quality guidelines 1999. Winnipeg: Canadian Council of Ministers of the Environment.
3. Schuler, M. S., Hintz, W. D., Jones, D. K., Lind, L. A., Mattes, B. M., Stoler, A. B., Sudol, K. A., & Relyea, R. A. (2017). How common road salts and organic additives alter freshwater food webs: in search of safer alternatives. Journal of Applied Ecology, 54(5), 1353–1361. https://doi.org/10.1111/1365-2664.12877
4. Gillis, P. L., Salerno, J., Bennett, C. J., Kudla, Y., & Smith, M. (2021). The Relative Toxicity of Road Salt Alternatives to Freshwater Mussels; Examining the Potential Risk of Eco-Friendly De-icing Products to Sensitive Aquatic Species. ACS ES&T Water, 1(7), 1628–1636. https://doi.org/10.1021/acsestwater.1c00096
