Spatial and temporal patterns in physical properties and dissolved oxygen in Lake Diefenbaker, a large reservoir on the Canadian Prairies

摘要: Abstract Lake Diefenbaker (LD) is a multi-purpose deep storage reservoir with complex longitudinal zonation. Despite the importance of LD to Saskatchewan, last comprehensive evaluation this large was completed 30 years ago. Therefore, an assessment key features (patterns in stratification, turbidity, and dissolved oxygen (DO)) undertaken during ice-free period 2011–2013 characterize conditions that may affect water quality, including climate change. In addition, these were compared expectations zonation concept (LZC) Kimmel Groeger (1984). The dimictic, summer mixing depths (10–20 m) similar between drought year (1984) current study. Sections hypolimnia became hypoxic, or sub-optimal for cold cool fish (≤ 5 mg/L). Volumetric hypolimnetic depletion rates 0.034 0.12 mg L/day overlapped other lakes reservoirs. would be prone anoxia had thermal stratification been prolonged another 2 4 weeks. experienced three years above average peak flows. flow 2013 brought high turbidity (e.g., 200 NTU) organic matter resulted metalimnetic DO minimum. Spatial patterns (but not DO) followed LZC. Drought 1984 reduced volumes, anoxic algal blooms. as Northern Plains continue warm, monitoring periods warranted, especially when droughts follow events.