Joshua C Koch, Ph.D.
Surface water / groundwater interactions; hyporheic zone hydrology and biogeochemistry; carbon, nitrogen, and phosphorus cycling; flow above / through frozen ground; preferential flow and soil pipe formation and transport.
Science and Products
Filter Total Items: 17
The Rusting of Arctic Rivers: Freshwater Ecosystems Respond to Rapidly Uptaking Metals
The water quality of streams and rivers in the Arctic is sensitive to rapid climate change and altered disturbance regimes.
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.
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...
Hydro-Ecology of Arctic Thawing (HEAT): Ecology
Permafrost thaw is leading to a myriad of changes in physical and chemical conditions throughout the Arctic.
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...
Groundwater Flow and Temperature Modeling to Predict Stream Temperatures in Beaver Creek, Kenai Peninsula, Alaska
Salmon are an important resource to the ecosystems, economy, and culture of the Kenai Peninsula, Alaska. However, salmon are under increasing stress due to warming water temperatures and decreasing stream flow. Groundwater is a major contributor to many streams that can help maintain fish habitat during low flows and contributes cooler water that regulates stream temperatures in the warm...
Assessment of Critical Landscape Conditions and Potential Change in the Coastal Plain of the Arctic National Wildlife Refuge to Support Habitat Management Decision Making
Areas along the Arctic coast are changing the fastest among all of Earth’s habitats due to climate change. The Arctic coast is a fragile ecosystem that provides habitat for migratory birds, endangered species, and species critical for local subsistence living. In this area, permafrost is thawing rapidly, changing how much and when water reaches rivers, ponds, lakes, wetlands and...
Beavers Impacting Tundra Ecosystems (BITE)
The range expansion of the North American beaver ( Castor canadensis) has implications for water quality, aquatic ecosystems, and fisheries in Arctic streams.
Biogeochemistry of glaciers
Significant change to the Arctic and sub-arctic water cycle is underway, impacting hydrologic and biogeochemical fluxes. In southcentral Alaska, glacier mass loss, changes to precipitation (including the rain/snow fraction), thawing ground ice, and vegetation encroachment will change both magnitude and timing of water and solute fluxes downstream. Although altered fluxes of limiting nutrients are...
Arctic Lake Food Webs
From 2011 to 2013 we investigated freshwater food webs of Arctic Coastal Plain lakes in Alaska to improve our understanding how Arctic freshwater food webs may respond to landscape change the warmer, drier future.
Wolverine Glacier Ecosystem Studies
This project is an extension of the long-term Wolverine Glacier Benchmark Glacier project and is improving our understanding of solutes and nutrients in glacier basins, and how they fuel downstream ecosystems.
Matanuska-Susitna Borough Wetland Modeling
This project aims to improve our understanding of the role of wetlands in controlling streamflow in southcentral Alaska using a groundwater – surface water flow model that can recreate the dynamic interactions between streams and wetlands.
Science and Products
Filter Total Items: 17
The Rusting of Arctic Rivers: Freshwater Ecosystems Respond to Rapidly Uptaking Metals
The water quality of streams and rivers in the Arctic is sensitive to rapid climate change and altered disturbance regimes.
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.
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...
Hydro-Ecology of Arctic Thawing (HEAT): Ecology
Permafrost thaw is leading to a myriad of changes in physical and chemical conditions throughout the Arctic.
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...
Groundwater Flow and Temperature Modeling to Predict Stream Temperatures in Beaver Creek, Kenai Peninsula, Alaska
Salmon are an important resource to the ecosystems, economy, and culture of the Kenai Peninsula, Alaska. However, salmon are under increasing stress due to warming water temperatures and decreasing stream flow. Groundwater is a major contributor to many streams that can help maintain fish habitat during low flows and contributes cooler water that regulates stream temperatures in the warm...
Assessment of Critical Landscape Conditions and Potential Change in the Coastal Plain of the Arctic National Wildlife Refuge to Support Habitat Management Decision Making
Areas along the Arctic coast are changing the fastest among all of Earth’s habitats due to climate change. The Arctic coast is a fragile ecosystem that provides habitat for migratory birds, endangered species, and species critical for local subsistence living. In this area, permafrost is thawing rapidly, changing how much and when water reaches rivers, ponds, lakes, wetlands and...
Beavers Impacting Tundra Ecosystems (BITE)
The range expansion of the North American beaver ( Castor canadensis) has implications for water quality, aquatic ecosystems, and fisheries in Arctic streams.
Biogeochemistry of glaciers
Significant change to the Arctic and sub-arctic water cycle is underway, impacting hydrologic and biogeochemical fluxes. In southcentral Alaska, glacier mass loss, changes to precipitation (including the rain/snow fraction), thawing ground ice, and vegetation encroachment will change both magnitude and timing of water and solute fluxes downstream. Although altered fluxes of limiting nutrients are...
Arctic Lake Food Webs
From 2011 to 2013 we investigated freshwater food webs of Arctic Coastal Plain lakes in Alaska to improve our understanding how Arctic freshwater food webs may respond to landscape change the warmer, drier future.
Wolverine Glacier Ecosystem Studies
This project is an extension of the long-term Wolverine Glacier Benchmark Glacier project and is improving our understanding of solutes and nutrients in glacier basins, and how they fuel downstream ecosystems.
Matanuska-Susitna Borough Wetland Modeling
This project aims to improve our understanding of the role of wetlands in controlling streamflow in southcentral Alaska using a groundwater – surface water flow model that can recreate the dynamic interactions between streams and wetlands.
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government