Canada is a country covered by vast networks of water. Rivers, streams, lakes and wetlands span thousands of kilometres, connecting the different parts of our landscapes.

As water moves through these systems, it carries with it traces of the places it has been. These traces are not just swept up from river beds and lake bottoms as the water moves through; they also come from the landscape surrounding the waterways. When rain falls, it seeps slowly into the soil or around the rocks it lands on. Some of that water is then absorbed and used by vegetation, some of it may go toward recharging stocks of underground water, and some of it is likely to continue on toward nearby freshwater systems, carrying with it whatever it picks up along its route. This means that rain that lands in an agricultural field may carry traces of that field. Depending on how that field is managed, you would expect to find more or less fertilizer and pesticides, more or less sediments. In a different context, such as a landscape covered by forest, the rain that moves toward waterways would again carry different sediments, different traces.

In my PhD research, I sought to find out what happens to a stream when you protect the land surrounding it. Is the water found in such a stream different from the water found in a stream that is not surrounded by protected land?

I wanted to know how protection affects streams because most protected areas are not created specifically with streams in mind. Yet, protecting a stream and the land that surrounds it could have an important effect on that stream — and, subsequently, on the people and animals that interact with it. After all, streams are great places for recreation. In the area surrounding streams, called the riparian zone, we can go for peaceful walks or find delicious wild foods like elderberries, blueberries and Labrador tea. Riparian zones store carbon in vegetation and soil, preventing greenhouse gases from further heating the atmosphere. On top of all that, streams and their riparian zones provide habitat for numerous species that we care about.

When land isn’t protected, it tends to be converted to produce or extract resources, and I wanted to find out what would happen to our protected streams if they did undergo such changes. In Canada, some common ways we convert land include clearing forest for agriculture and harvesting timber. So, I sought to measure differences between streams surrounded by protected forest, unprotected forest, timber harvesting, and agriculture.

I figured the best way to answer my questions would be to visit several streams and collect data. Using a geographic information system — a computer tool that allows you to map, search and analyze data — I located 28 different but comparable streams that met my research criteria. All of the streams are located in Quebec, between two provincial parks, Mont-Tremblant and Monts-Valin. I spent a day or two at each of them, gathering information about what scientists call “ecosystem services,” which are essentially the different ways that humans benefit from nature. Specifically, I was interested in the provision of clean water, wild foods, carbon storage, recreational trails, habitat quality and biodiversity.

I collected water and insects, I counted the elderberry, blueberry, Labrador tea, raspberry and wintergreen plants that I saw, I identified and measured trees, and I looked for indicators of habitat that diverse species are able to live in. Then, I spent months in the laboratory analyzing these samples and months at the computer figuring out what they meant. I wanted to know what all this information could tell us about how protection and land use and cover affect the ecosystem services provided by streams and their riparian zones, as well as biodiversity.