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The Rusting of Arctic Rivers: Freshwater Ecosystems Respond to Rapidly Uptaking Metals Active

By Alaska Science Center September 14, 2022

The water quality of streams and rivers in the Arctic is sensitive to rapid climate change and altered disturbance regimes.

Return to Ecosystems or Water >> Fish and Aquatic Ecology

Widespread permafrost thaw, thaw-induced erosion, and wildfires have altered the concentration and flux of organic carbon, nutrients, and trace metals in Arctic rivers. Subsequently, changes in surface waters can impact the habitability for biota and growth rates for fish. Recent observations from Arctic Alaska indicate that waters draining permafrost landscapes may be susceptible to iron and carbon mobilization following thaw. One consequence of these altered iron-cycling processes is the abrupt change in color (orange) of stream and river reaches, reflecting a dramatic shift in water quality. Although the exact mechanisms are yet to be determined, evidence indicates that shifting hydrological and oxidation-reduction processes associated with permafrost thaw may function to transport high concentrations of iron in dissolved and colloidal forms from thawing soils to streams. Preliminary observations suggest that orange stream reaches have higher iron concentrations, less dissolved oxygen, and more acidic water than nearby clearwater streams. Further, the conversion of streams from clear to orange water appears to reflect a considerable deterioration of habitat for benthic macroinvertebrates and fish.

In 2022, USGS began working with the National Park Service, University of California-Davis, University of Alaska-Anchorage, and Alaska Pacific University to address several research objectives including:

  1. Map the spatial distribution of orange streams and the onset of stream color change across national parks in the Arctic Inventory & Monitoring Network. 
  2. Quantify the effects of iron and other metal inputs on water quality in Arctic streams and determine landscape controls on metal mobilization. 
  3. Assess consequences of shifts in stream water quality on stream biota, including biofilm, macroinvertebrates, and resident fish communities.

Funding: USGS Changing Arctic Ecosystem Initiative and USGS-NPS Water Quality Partnership

Map of Arctic rivers study sites with six stars marking sites. Three aerial images with orange streams below map.
Sources/Usage: Public Domain. Visit Media to see details.
Map of orange stream observations across Arctic Inventory and Monitoring Network (ARCN) parks in northern Alaska. Picture inserts show aerial images of select iron-impacted, orange streams. 
Kugururok River confluence showing both orange water and blue water. Shrubs along bank with mountains in background.
Sources/Usage: Public Domain. Visit Media to see details.
Mainstem of Kugururok River located in Noatak National Park and Preserve, Alaska.

Below are other science projects associated with this project.

link
Spawing sockeye salmon in a Matanuska River side channel, Alaska

Fish and Aquatic Ecology

Fish and aquatic habitats in Alaska support important commercial, sport, and subsistence fisheries and provide forage fish that support wildlife populations. The USGS Alaska Science Center conducts interdisciplinary research to inform local, state, federal, and international policy makers regarding conservation of fish, aquatic species, and their habitats. We work collaboratively with hydrologists...
By
Ecosystems Mission Area, Species Management Research Program, Alaska Science Center
link

Fish and Aquatic Ecology

Fish and aquatic habitats in Alaska support important commercial, sport, and subsistence fisheries and provide forage fish that support wildlife populations. The USGS Alaska Science Center conducts interdisciplinary research to inform local, state, federal, and international policy makers regarding conservation of fish, aquatic species, and their habitats. We work collaboratively with hydrologists...
Learn More
link
Yukon River near Eagle, Alaska

Q&A: Arctic Rivers Project

Alaska is home to numerous cultural and linguistic Indigenous groups and the largest number of Federally Recognized Tribes in the United States. Indigenous Alaskans, often living in rural remote communities, are facing multiple impacts due to climate change. As infrastructure, landscapes, and subsistence resources continue to be impacted by warming temperatures, the safety, well-being, and...
By
Alaska Science Center
link

Q&A: Arctic Rivers Project

Alaska is home to numerous cultural and linguistic Indigenous groups and the largest number of Federally Recognized Tribes in the United States. Indigenous Alaskans, often living in rural remote communities, are facing multiple impacts due to climate change. As infrastructure, landscapes, and subsistence resources continue to be impacted by warming temperatures, the safety, well-being, and...
Learn More
link
Scientist walking up the Akilik River with a minnow trap to catch fish

Hydro-Ecology of Arctic Thawing (HEAT): Ecology

Permafrost thaw is leading to a myriad of changes in physical and chemical conditions throughout the Arctic.
By
Land Management Research Program, Species Management Research Program, Alaska Science Center
link

Hydro-Ecology of Arctic Thawing (HEAT): Ecology

Permafrost thaw is leading to a myriad of changes in physical and chemical conditions throughout the Arctic.
Learn More
link
The Agashashok River Watershed

Arctic – Boreal Catchment Studies

Catchment hydrology focuses on the movement of water and solutes from landscapes to waterbodies. Our research addresses questions such as: Where is the stream water coming from? How long did it take to get here? What solutes, nutrients, and/or contaminants did the water pick up along the way? Because streams and lakes gather water and solutes, we can learn about the entire watershed by studying...
By
Alaska Science Center
link

Arctic – Boreal Catchment Studies

Catchment hydrology focuses on the movement of water and solutes from landscapes to waterbodies. Our research addresses questions such as: Where is the stream water coming from? How long did it take to get here? What solutes, nutrients, and/or contaminants did the water pick up along the way? Because streams and lakes gather water and solutes, we can learn about the entire watershed by studying...
Learn More
link
The north fork of the Agashashok River

Hydro-Ecology of Arctic Thawing (HEAT): Hydrology

The Arctic is warming at higher rates than much of the rest of the world. For Alaska, this results in changes in hydrology and ecosystems – permafrost is thawing, changing landscapes and releasing nutrients to soils and streams.
By
Land Management Research Program, Alaska Science Center
link

Hydro-Ecology of Arctic Thawing (HEAT): Hydrology

The Arctic is warming at higher rates than much of the rest of the world. For Alaska, this results in changes in hydrology and ecosystems – permafrost is thawing, changing landscapes and releasing nutrients to soils and streams.
Learn More
Filter Total Items: 24
Orange color/staining in river. Brown low vegetation and patches of snow along riverbank. Snow on mountains with blue skies.
link
Orange colored water flowing into Kugororuk River, Alaska. Brown ground with vegetation, snow patches with mountains sky.
link
Kugororuk River showing orange water on left side and clear water on right. Low shrubs with mountains and blue sky.
link
Orange colored water flowing into the clear Kugaroruk River. Brown vegetation to the left of orange water. Mountains and sky.
link
Close up of orange water in Kugororuk River, Alaksa. Shrubs and mountains with blue sky.
link
The confluence of the Anakok River, Sheep Creek, and the Salmon River. Sand bar in middle with spruce trees and snow.
link
View of orange staining on snow of the Anaktok River, Alaska. The tributary is at bottom of valley with mountains.
link
The Anaktok River with orange staining. Snow on both sides of river with low vegetation. Snow covered mountains to left.
link
Riverbed with rocks. The water and riverbed are a brown orangish color. Orange staining on snow with shrubs along riverbank.
link
Orange staining of water and ground in river. Snow with low shrubs along bank of river with mountains and clear blue skies.
link
Aerial view of orange staining on snow and ice in a braidplain of the Nakolikruk River, Alaska. Brown ground surrounds river.
link
View of orange staining on snow of the Nakolikruk River, Alaska. Brown ground, snow patch, mountain, blue sky and clouds.
link
Aerial view of orange water and snow in a braidplain of the Nakolikruk River, Alaska. Mountains in background.
link
Kugururok River confluence showing both orange water and blue water. Shrubs along bank with mountains in background.
link
Orange water in tributary of Kugururok River. Shrubs along the bank with hills in the background.
link
Deposition on tributary of Salmon River. A dead tree lays across the water and another is on the bank next to hill.
link
A tributary of the Salmon River located in the Kobuk River National Park, Alaska. The tributary is orange in color.
link
Mainstem of Salmon River with cloudy, brownish orange water. Fall vegetation and hill surrounding riverbanks.
link
Tributary of Salmon River, Alaska with orange color flowing into river. Fall vegetation and hill in the background.
link
Hillside fall colors on the North fork of the Agashashok River. The foreground shows dead shrubs from iron seep.
link
Map of Arctic rivers study sites with six stars marking sites. Three aerial images with orange streams below map.
link
link

Why are Arctic Rivers Turning Orange?

Permafrost thaw may be contributing to discoloration of Arctic rivers by exposing iron-bearing minerals that were previously frozen and are now...

Read Article
  • Overview

    The water quality of streams and rivers in the Arctic is sensitive to rapid climate change and altered disturbance regimes.

    Return to Ecosystems or Water >> Fish and Aquatic Ecology

    Widespread permafrost thaw, thaw-induced erosion, and wildfires have altered the concentration and flux of organic carbon, nutrients, and trace metals in Arctic rivers. Subsequently, changes in surface waters can impact the habitability for biota and growth rates for fish. Recent observations from Arctic Alaska indicate that waters draining permafrost landscapes may be susceptible to iron and carbon mobilization following thaw. One consequence of these altered iron-cycling processes is the abrupt change in color (orange) of stream and river reaches, reflecting a dramatic shift in water quality. Although the exact mechanisms are yet to be determined, evidence indicates that shifting hydrological and oxidation-reduction processes associated with permafrost thaw may function to transport high concentrations of iron in dissolved and colloidal forms from thawing soils to streams. Preliminary observations suggest that orange stream reaches have higher iron concentrations, less dissolved oxygen, and more acidic water than nearby clearwater streams. Further, the conversion of streams from clear to orange water appears to reflect a considerable deterioration of habitat for benthic macroinvertebrates and fish.

    In 2022, USGS began working with the National Park Service, University of California-Davis, University of Alaska-Anchorage, and Alaska Pacific University to address several research objectives including:

    1. Map the spatial distribution of orange streams and the onset of stream color change across national parks in the Arctic Inventory & Monitoring Network. 
    2. Quantify the effects of iron and other metal inputs on water quality in Arctic streams and determine landscape controls on metal mobilization. 
    3. Assess consequences of shifts in stream water quality on stream biota, including biofilm, macroinvertebrates, and resident fish communities.

    Funding: USGS Changing Arctic Ecosystem Initiative and USGS-NPS Water Quality Partnership

    Map of Arctic rivers study sites with six stars marking sites. Three aerial images with orange streams below map.
    Sources/Usage: Public Domain. Visit Media to see details.
    Map of orange stream observations across Arctic Inventory and Monitoring Network (ARCN) parks in northern Alaska. Picture inserts show aerial images of select iron-impacted, orange streams. 
    Kugururok River confluence showing both orange water and blue water. Shrubs along bank with mountains in background.
    Sources/Usage: Public Domain. Visit Media to see details.
    Mainstem of Kugururok River located in Noatak National Park and Preserve, Alaska.
  • Science

    Below are other science projects associated with this project.

    link
    Spawing sockeye salmon in a Matanuska River side channel, Alaska

    Fish and Aquatic Ecology

    Fish and aquatic habitats in Alaska support important commercial, sport, and subsistence fisheries and provide forage fish that support wildlife populations. The USGS Alaska Science Center conducts interdisciplinary research to inform local, state, federal, and international policy makers regarding conservation of fish, aquatic species, and their habitats. We work collaboratively with hydrologists...
    By
    Ecosystems Mission Area, Species Management Research Program, Alaska Science Center
    link

    Fish and Aquatic Ecology

    Fish and aquatic habitats in Alaska support important commercial, sport, and subsistence fisheries and provide forage fish that support wildlife populations. The USGS Alaska Science Center conducts interdisciplinary research to inform local, state, federal, and international policy makers regarding conservation of fish, aquatic species, and their habitats. We work collaboratively with hydrologists...
    Learn More
    link
    Yukon River near Eagle, Alaska

    Q&A: Arctic Rivers Project

    Alaska is home to numerous cultural and linguistic Indigenous groups and the largest number of Federally Recognized Tribes in the United States. Indigenous Alaskans, often living in rural remote communities, are facing multiple impacts due to climate change. As infrastructure, landscapes, and subsistence resources continue to be impacted by warming temperatures, the safety, well-being, and...
    By
    Alaska Science Center
    link

    Q&A: Arctic Rivers Project

    Alaska is home to numerous cultural and linguistic Indigenous groups and the largest number of Federally Recognized Tribes in the United States. Indigenous Alaskans, often living in rural remote communities, are facing multiple impacts due to climate change. As infrastructure, landscapes, and subsistence resources continue to be impacted by warming temperatures, the safety, well-being, and...
    Learn More
    link
    Scientist walking up the Akilik River with a minnow trap to catch fish

    Hydro-Ecology of Arctic Thawing (HEAT): Ecology

    Permafrost thaw is leading to a myriad of changes in physical and chemical conditions throughout the Arctic.
    By
    Land Management Research Program, Species Management Research Program, Alaska Science Center
    link

    Hydro-Ecology of Arctic Thawing (HEAT): Ecology

    Permafrost thaw is leading to a myriad of changes in physical and chemical conditions throughout the Arctic.
    Learn More
    link
    The Agashashok River Watershed

    Arctic – Boreal Catchment Studies

    Catchment hydrology focuses on the movement of water and solutes from landscapes to waterbodies. Our research addresses questions such as: Where is the stream water coming from? How long did it take to get here? What solutes, nutrients, and/or contaminants did the water pick up along the way? Because streams and lakes gather water and solutes, we can learn about the entire watershed by studying...
    By
    Alaska Science Center
    link

    Arctic – Boreal Catchment Studies

    Catchment hydrology focuses on the movement of water and solutes from landscapes to waterbodies. Our research addresses questions such as: Where is the stream water coming from? How long did it take to get here? What solutes, nutrients, and/or contaminants did the water pick up along the way? Because streams and lakes gather water and solutes, we can learn about the entire watershed by studying...
    Learn More
    link
    The north fork of the Agashashok River

    Hydro-Ecology of Arctic Thawing (HEAT): Hydrology

    The Arctic is warming at higher rates than much of the rest of the world. For Alaska, this results in changes in hydrology and ecosystems – permafrost is thawing, changing landscapes and releasing nutrients to soils and streams.
    By
    Land Management Research Program, Alaska Science Center
    link

    Hydro-Ecology of Arctic Thawing (HEAT): Hydrology

    The Arctic is warming at higher rates than much of the rest of the world. For Alaska, this results in changes in hydrology and ecosystems – permafrost is thawing, changing landscapes and releasing nutrients to soils and streams.
    Learn More
  • Multimedia
    Filter Total Items: 24
    Orange color/staining in river. Brown low vegetation and patches of snow along riverbank. Snow on mountains with blue skies.
    link
    Orange colored water flowing into Kugororuk River, Alaska. Brown ground with vegetation, snow patches with mountains sky.
    link
    Kugororuk River showing orange water on left side and clear water on right. Low shrubs with mountains and blue sky.
    link
    Orange colored water flowing into the clear Kugaroruk River. Brown vegetation to the left of orange water. Mountains and sky.
    link
    Close up of orange water in Kugororuk River, Alaksa. Shrubs and mountains with blue sky.
    link
    The confluence of the Anakok River, Sheep Creek, and the Salmon River. Sand bar in middle with spruce trees and snow.
    link
    View of orange staining on snow of the Anaktok River, Alaska. The tributary is at bottom of valley with mountains.
    link
    The Anaktok River with orange staining. Snow on both sides of river with low vegetation. Snow covered mountains to left.
    link
    Riverbed with rocks. The water and riverbed are a brown orangish color. Orange staining on snow with shrubs along riverbank.
    link
    Orange staining of water and ground in river. Snow with low shrubs along bank of river with mountains and clear blue skies.
    link
    Aerial view of orange staining on snow and ice in a braidplain of the Nakolikruk River, Alaska. Brown ground surrounds river.
    link
    View of orange staining on snow of the Nakolikruk River, Alaska. Brown ground, snow patch, mountain, blue sky and clouds.
    link
    Aerial view of orange water and snow in a braidplain of the Nakolikruk River, Alaska. Mountains in background.
    link
    Kugururok River confluence showing both orange water and blue water. Shrubs along bank with mountains in background.
    link
    Orange water in tributary of Kugururok River. Shrubs along the bank with hills in the background.
    link
    Deposition on tributary of Salmon River. A dead tree lays across the water and another is on the bank next to hill.
    link
    A tributary of the Salmon River located in the Kobuk River National Park, Alaska. The tributary is orange in color.
    link
    Mainstem of Salmon River with cloudy, brownish orange water. Fall vegetation and hill surrounding riverbanks.
    link
    Tributary of Salmon River, Alaska with orange color flowing into river. Fall vegetation and hill in the background.
    link
    Hillside fall colors on the North fork of the Agashashok River. The foreground shows dead shrubs from iron seep.
    link
    Map of Arctic rivers study sites with six stars marking sites. Three aerial images with orange streams below map.
    link
  • News
    link

    Why are Arctic Rivers Turning Orange?

    Permafrost thaw may be contributing to discoloration of Arctic rivers by exposing iron-bearing minerals that were previously frozen and are now...

    Read Article