From the Rockies to the Prairies: Spatio-Temporal Changes in Water Quality in Tributaries of the South Saskatchewan River
Abstract
The province of Alberta is one of the largest agricultural producers in Canada. Here, most agricultural activity is located within the South Saskatchewan River basin (SSRB), which includes the Oldman, Bow and Red Deer Rivers. They also provide critical habitat to diverse fauna and flora. These rivers have been incrementally modified by a wide range of activities, yet the responses of water quality variables are unclear, especially in a multiple-stressor context. To define the spatio-temporal patterns of key water quality variables that potentially alter food web structure and functioning, we explored multi-decadal patterns using existing provincial monitoring datasets. Surface water quality parameters (nutrients, temperature, dissolved oxygen, ions, conductivity and pH) sampled at roughly monthly frequencies were taken at three sites in each river, above, near, and downstream of major urban and agricultural land zones. Spatially, averages of data from the past decade revealed that while nutrient concentrations and conductivity increase moving downstream in all three rivers, spatial gradients of temperature, turbidity, pH and dissolved oxygen were less systematic. Across sites, downstream in the Red Deer River exhibited the most extreme water quality conditions. Within last three decades, conductivity, inorganic nitrogen and pH have simultaneously increased at most sites, while turbidity and phosphorus concentrations have decreased. These results demonstrate that simultaneous changes in multiple water quality parameters must be considered to best understand human impacts on food webs within SSRB tributaries. These findings help to define how anthropogenic activities are simultaneously changing key aquatic parameters that regulate aquatic ecosystem health.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMB047.0007G
- Keywords:
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- 0414 Biogeochemical cycles;
- processes;
- and modeling;
- BIOGEOSCIENCES;
- 0439 Ecosystems;
- structure and dynamics;
- BIOGEOSCIENCES;
- 0458 Limnology;
- BIOGEOSCIENCES;
- 0465 Microbiology: ecology;
- physiology and genomics;
- BIOGEOSCIENCES