Canadian lakes are following opposite phosphorus trajectories
WHAT THE EVIDENCE SAYS
Remote-sensing reconstruction trained with 35,452 field measurements and 386,727 Landsat images estimates 1984–2025 total phosphorus in 15,240 lakes larger than five square kilometres. Arctic tundra lake estimates increased; boreal, temperate, agricultural and urban watershed classes mostly declined.
WHY IT MATTERS / OUR READ
National lake averages disguise different watershed mechanisms and may misdirect monitoring effort.
CAVEATS / UNCERTAINTY
These are model estimates, not a direct annual water sample at every lake; small lakes were excluded.
SOURCE
Communications Earth & Environment — Canadian lake analysis (2026)
View original evidence ↗
Modeled Arctic phosphorus increases contrast with declines across several southern watershed classes.
Read the Wild Lands assessment →