Tag Archives: Ecohydrology

URA fieldwork project: nutrient concentrations in select rivers and wetlands in Guelph, ON

— by Aidan Doak, on behalf of myself and Thanuja Thavarasa

On May 8th, 2019, Thanuja and I kicked off our summer undergraduate research assistant (URA) positions at the University of Guelph. There were many potential projects planned for the months to come and a water chemistry analysis project was at the top of our list. The goal was to observe and compare any relationships between nitrate and phosphate concentrations in different water systems within the Grand River Watershed. The city of Guelph, located right in our backyard, became our primary focus. We collected water samples from six sites after significant rainfall events.  We have provided a map showing our six site locations below (Figure 1) and a table displaying sampling dates and precipitation totals since the previous outing (Table 1).

Samples were tested for electrical conductivity and oxygen reduction potential in the field. Afterwards, they were brought back to the lab for turbidity measurements, filtration and analysis of nitrate and phosphate concentrations. We have compiled our data and graphed some of our results below. The straight blue line in each figure highlights the 0.03 mg/L provincial water quality standard for phosphate.

The Eramosa River and the Speed River were our two river sites, with relatively wide channels (Figure 2A and 2B). Both sites demonstrate a similar nutrient behavior; consistently higher concentrations of nitrates compared to the wetland sites (Figure 3), and phosphate concentrations that vary over time more compared to wetland sites. Phosphate concentrations fluctuate within 0.03 mg/L of the provincial water quality standard. The known, higher mobility of nitrate compared to phosphate could explain this behavior. The high levels of nitrate are potentially a product of recent rainfall events, washing nitrates downstream.

A riparian wetland located next to the Speed River was sampled at two locations; the first was closest to the river and the second was adjacent to a walking trail (Figure 3A and 3B). The wetland experienced many expansions and contractions throughout the two-month sampling period. On May 21st, there was no surface water at the Speed River Wetland Trail location so we could not take a sample. The Speed River Wetland Trail location experienced phosphate concentrations three times larger than the provincial standard, while the adjacent Speed River Wetland location had a phosphate concentration that was ten-fold the same standard. The ability of soils to retain phosphate, paired with the expansion and contraction characteristics of the wetland adjacent to the Speed River, may explain those dynamics. Wetlands are nutrient sinks as they prevent nutrients from reaching rivers and streams, which is an environmental benefit.

The Solstice Wetland (Figure 3D) exhibited a different relationship between phosphate and nitrate concentrations compared to the other river and wetland sites. The Solstice Wetland behaved as a perennial wetland as it always had surface water in the depression during the two-month sampling period. On the other hand, the Speed River Wetland is intermittent: it expanded and contracted to the extent that no surface water was present on multiple sampling days. At the Solstice Wetland site, nitrate and phosphate concentrations were strongly correlated, as indicted by their synchronous increasing and decreasing behaviors.



What does a summer job in hydrology entail? Meet Janelle Laing…

FaceShot_JanelleJanelle, an Environmental Science student at the University of Winnipeg, joined the WSRP in the summer of 2015 as an Ecohydrology Research Assistant to explore whether plants are preferentially utilizing tightly-bound water over free flowing water in various settings. Within a short period of time, Janelle learned a great combination of laboratory and field sampling techniques with the luxury of having her field sites within walking distance. Of course, Janelle also learned that as with any field-based project, one should always expect the unexpected as unforeseen situations may arise that are beyond control (e.g., “unforecasted” rainfall events, malfunctioning equipment and so on). Although frustrating at times, her struggles to sample appropriately sized and aged twigs from trees remains one of Janelle’s more memorable times when reflecting upon her first summer with the WSRP. And like many others, Janelle has appreciated the opportunities to work outdoors and with others in the group. Janelle’s work has continued throughout her studies into 2016 as she used the data collected during her summer work for her Honor’s Thesis.

Interview done and profile written by Jonathon Belanger

Our group at the 2016 CGU-CMOS meeting

Our group will be sharing findings about new research in surface and vadose zone hydrology, ecohydrohydrology and water water quality dynamics… with a strong focus on the Prairies. If you will be in Fredericton, NB between May 29 and June 2, 2016 for the 50th CMOS Congress & joint CGU Annual Meeting, come talk to us! List of presentations below:

Ali, G., Wilson, H., Penner, A., Ross, C., Rabie, M., Haque, Md. A., and Elliott, J. (INVITED). ‘Linking phosphorous export dynamics to landscape heterogeneity and climatic variability: can c-Q relations help?’

Haque, Md. A., Ali, G., Ross, C., Schmall, A., and Bansah, S. ‘Water storage dynamics in geographically isolated wetlands in the Prairie Pothole Region’.

Bansah, S., Ali, G., Haque, Md. A., Laing, J., and Schmall, A. ‘A quick evaluation of water isotopic signatures and water travel times in a cold Canadian Prairie watershed’.

Ross, C., Ali, G., Belanger, J., Schmall, A., Walker, M., and Laing, J. ‘Assessment of the relationship between near-surface soil moisture and runoff generation in a near-level Prairie watershed’.

Rabie, M., Ali, G., Spence, C., Schmall, A., Ross, C., Haque, Md. A., and Bansah, S. ‘Variability of water quality in space and time in a cold, mesoscale, heavily engineered Prairie watershed’.

Laing, J., Ali, G., Casson, N., Moore, D., Hanson, M., Belanger, J., Bansah, S., Walker, M., Blunden, L., and Ross, C. ‘Plant water usage in a Canadian Prairie context: Using stable water isotopes to identify uptake sources’.