Have you noticed that water bodies are looking a little bit MURKIER?

Perhaps you can no longer “see clearly” through the water at your cottage or your nearby lake.

Brownification may be the reason behind it.

It signifies an increase in the “yellow-brown colour” of lake and stream water caused by dissolved organic matter.

This brownification affects lake and stream ecosystems because it drastically reduces the penetration of solar rays into the water body. These ecosystems then struggle with aquatic plant and animal production, like algae, invertebrates, and fish. It can also affect recreation activities – like swimming and fishing.

The impacts of climate change can increase the brownification of our water bodies – changing their biological community composition and structure drastically.

Sandra Klemet-N’Guessan, a second year MSc student at Trent University, is studying brownification effects on aquatic animals and how to predict when they will occur.

Brownification affects water bodies:

  • Temperature;
  • The amount of habitat suitable for animals; and
  • Plant and animal production. 

Using aquatic animals’ excretion (i.e. urine), position in the food web (i.e. their diet), and the gradient of dissolved organic matter (i.e. decayed vegetation) Sandra can better understand the effects that brownification has on the water bodies.

She is combining two different methods to conduct her research: big data and the experimental approach.

  1.  BIG DATA –  consists of using an already existing database of the nutrient content of animals’ excretion in various aquatic ecosystems in North America and Europe. Sandra is looking for trends.
  2. EXPERIMENTAL APPROACH – consists of collecting different fish species that have different diets and placing them in bags to let the animals urinate . She has collected species from 11 streams and will collect more species from 9 lakes

Sandra expects to find a “hump” shaped relationship between the nutrient content of animals’ excretion and dissolved organic matter. She hypothesizes that as dissolved organic matter increases, aquatic animals will release more nutrients back into the ecosystem.

Past a certain threshold, dissolved organic matter levels may lead to a decrease in the amount of nutrients released back into the ecosystem…. meaning less plant and animal production and less species!

Understanding how aquatic animals contribute to the cycling of nutrients is essential to predict the future state of aquatic ecosystems. Sandra’s research is helping other scientists better understand this process.

Thank you Sandra for your important research to keep our water bodies healthy for future generations to come and for explaining “brownification”.

Here is what Sandra has to say about her experience at Trent University:

Trent University has given me the opportunity to basically study the effect of global change in my backyard. First, Trent’s Symons campus is a beautiful campus, where the Otonabee river separates two banks surrounded by drumlins and nature areas; I could not find better inspiration for my work (and I am sometimes just 10-30 min away by car from my field sites)! Second, my graduate program, the Environmental & Life Sciences program, features a dynamic group of scientists from both the academic (Trent University) and government sectors (Ministry of Natural Resources) which allows students to have access to a large network of researchers and environmental practitioners across Ontario and Canada. Lastly, Trent and the city of Peterborough that hosts it are home to a strong and supportive community of students, families, and elders where promising sustainable initiatives are emerging. What not to love about it?