http://dx.doi.org/10.1016/B978-0-12-819166-8.00128-6

Culp, J.M., Lento., J. (2022) High latitude rivers: ecosystems shaped by environmental extremes. Encyclopedia of Inland Waters (Second Edition) Volume 2, 2022, Pages 586-597. http://dx.doi.org/10.1016/B978-0-12-819166-8.00128-6

Aim The unique aspects of high latitude rivers are discussed including environmental drivers of biotic structure and function, and the effects of development and climate warming on these ecosystems. Ecology of high latitude rivers The physical-chemical environment of these rivers is dominated by cold temperatures and river ice. Spring ice breakup creates intense disturbance that affects the substrate and water chemistry. Nutrient limitation typically limits primary production and heterotrophic processes often dominate ecosystem metabolism, which supports benthic invertebrate and fish production. Diversity of benthos and fish decreases at higher latitudes due to cold temperatures and barriers to colonization. Many fish species are important food sources for Indigenous Peoples. Climate change effects on biodiversity Climate-related increases in water temperature cause changes in diversity as species physiological tolerances are exceeded and other species extend their ranges northward. Permafrost thaw mobilizes nutrients and major ions that can increase ecosystem productivity, while mud slurries from thaw slumps can transport large amounts of terrestrial material into stream systems. Effects of human development High latitude rivers receive contaminants from various sources including atmospheric transport, mineral extraction, landuse change, road development, wastewater discharge, and hydropower generation. Pollutant impacts include biomagnification, acid deposition and altered water chemistry. Conclusion Climate warming will cause substantial change to high latitude river ecosystems and associated flora and fauna. Permafrost thaw mobilizes various nutrients and produces thaw slump sedimentation. The cumulative effects of climate change and pollution will be difficult to predict. Improved baseline knowledge of these ecosystems is needed to advance the ability to model and forecast future ecosystem state

http://dx.doi.org/10.1016/B978-0-12-819166-8.00128-6