Sediment phosphorus composition across lakes of the Canadian prairie region

The Prairie region of Canada is a key agricultural region of the nation,
but one with important stressors impacting water quality and security.
Within the prairies, rates of internal phosphorus (P) loading and trophic
status of lakes are known to be high, and cyanobacterial blooms are
common, owing in part to nutrient-rich soils, human activities in the
watersheds, and often shallower lakes. However, there is important
variation in the region in trophic status, internal loading, and sediment
geochemistry. We characterized the variation in lake sediment composition,
water chemistry, lake and watershed attributes expected to affect sediment
P cycling within the prairie region (the southern portion of the provinces
of Manitoba, Saskatchewan, and Alberta; Boreal Plains and Prairies
Ecozones). We aim to help understand what drives variation in sediment P
speciation, and porewater SRP. Multiple attributes expected to affect P
cycling varied substantively between the two ecozones (e.g., lake trophic
status, pH, salinity, and dissolved sulfate were higher in Prairie ecozone
lakes than in the Boreal Plains ecozone). While the studied ecozones
differ in terms of soils, land use, lake water chemistry, lake trophic
status, and sediment P fractions, the ecozones themselves were not
associated with significant differences in porewater SRP.