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Ecosystem Biogeochemistry

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By Fort Collins Science Center March 14, 2025

Biogeochemical cycles impart significant control on ecosystem structure, function, and ecosystem services, such as nutrient sequestration, transformation, long-term storage, mitigation of water quality concerns, and carbon fixation/mineralization processes that support local food webs. 

Return to the GSIL Homepage
Media
a gloved hand holds four capped test tubes containing brown liquids, blue door in background
Sources/Usage: Public Domain. View Media Details
Extracts of lignon phenol from peat in the Great Dismal Swamp

Isotope geochemistry offers novel insight into sources, processes, and fates of a broad array of elements that are relevant to ecosystem science. These geochemical insights also integrate well with food web studies, offering a more complete assessment of critical nutrient sources, fixation, and ultimately secondary production. 

This project includes studies that explicitly focus on elements (for example, carbon, nitrogen, sulfur) that have strong linkages between geochemical compartments and biological production (for example, nutrient sources/fates, decomposition, carbon fixation, food webs) as well as related processes for non-essential elements (for example, bioaccumulation) and long-term storage/permanence important to ecosystem function and persistence (for example, soil carbon). The latter also includes studies of natural environmental archives (for example, tree rings, sediments) that inform on historical and contemporary ecosystem health with the goal of aiding conservation and management. 

Media
a swampy wetland with dead tree trunks coming up from the water, cloudy skies
Sources/Usage: Public Domain. View Media Details
USGS scientists and collaborators investigated the effects of disturbance on peatland carbon chemistry in the Great Dismal Swamp, which has experienced fires, drought-like conditions, and other major disturbances over the last 200 years. Read more.
a laboratory space containing technical equipment, drawers, desks, and chairs

Geology, Geophysics, and Geochemistry Stable Isotope Laboratory (GSIL)

The GSIL is a state-of-the-art facility located on the Denver Federal Center that specializes in the measurement of light stable isotope — Hydrogen (H), Carbon (C), Nitrogen (N), Oxygen (O), and Sulfur (S) — compositions and other chemical and biomarker analytes in matrices relevant to the Earth sciences. Chemical and isotopic tracers offer novel insights into ecosystem biogeochemistry, food webs...
By
Fort Collins Science Center, Geology, Geophysics, and Geochemistry Science Center
Geology, Geophysics, and Geochemistry Stable Isotope Laboratory (GSIL)

Geology, Geophysics, and Geochemistry Stable Isotope Laboratory (GSIL)

The GSIL is a state-of-the-art facility located on the Denver Federal Center that specializes in the measurement of light stable isotope — Hydrogen (H), Carbon (C), Nitrogen (N), Oxygen (O), and Sulfur (S) — compositions and other chemical and biomarker analytes in matrices relevant to the Earth sciences. Chemical and isotopic tracers offer novel insights into ecosystem biogeochemistry, food webs...
Learn More
Polar bear mother and two cubs on the Beaufort Sea ice.

Food Webs and Wildlife Nutrition

Wildlife nutrition is an essential element of fitness, and contextualizing resource use within the broader framework of local and regional food webs is paramount to species health, function, and management.
By
Fort Collins Science Center
Food Webs and Wildlife Nutrition

Food Webs and Wildlife Nutrition

Wildlife nutrition is an essential element of fitness, and contextualizing resource use within the broader framework of local and regional food webs is paramount to species health, function, and management.
Learn More
Breeding colony of terns on Breton Island

Wildlife Biogeography

The distribution of species across the landscape is of great interest to biologists, owing to a critical need to understand the connectivity of disparate habitats for species that undertake broadscale movements. Indeed, habitat quality and quantity are thought to be important drivers of occurrence and distribution, and numerous studies have demonstrated fitness-related consequences as evidenced in...
By
Fort Collins Science Center
Wildlife Biogeography

Wildlife Biogeography

The distribution of species across the landscape is of great interest to biologists, owing to a critical need to understand the connectivity of disparate habitats for species that undertake broadscale movements. Indeed, habitat quality and quantity are thought to be important drivers of occurrence and distribution, and numerous studies have demonstrated fitness-related consequences as evidenced in...
Learn More
Two scientists work on a study of mercury contamination in the water.

Environmental Stressors

Environmental stressors that impact habitat and wildlife species include: abiotic factors (for example, land use, temperature); soil, air, and water quality (for example, eutrophication, contaminants); and disturbance (for example, fire, drought, hurricanes, species invasions). Understanding how these stressors impact ecosystems is critical to conservation and management.
By
Fort Collins Science Center
Environmental Stressors

Environmental Stressors

Environmental stressors that impact habitat and wildlife species include: abiotic factors (for example, land use, temperature); soil, air, and water quality (for example, eutrophication, contaminants); and disturbance (for example, fire, drought, hurricanes, species invasions). Understanding how these stressors impact ecosystems is critical to conservation and management.
Learn More

Water chemistry, stable isotopes, and trace metals in sediment, water and biota in Torch Lake and Gratiot Lake, Keweenaw Peninsula, Michigan, USA, July and October 2021 Water chemistry, stable isotopes, and trace metals in sediment, water and biota in Torch Lake and Gratiot Lake, Keweenaw Peninsula, Michigan, USA, July and October 2021

This data release includes sampling location data, laboratory processed surface water chemistry data (anions, cations, total nitrogen, dissolved organic carbon, deuterium, trace metals), laboratory processed pore water chemistry data (anions, cations, total nitrogen, dissolved organic carbon, trace metals), laboratory process sediment data (trace metals), and whole-body trace metal...
By
Columbia Environmental Research Center

Geochemical Analyses of Water, Mine tailings, Fluvial Suspended Sediments, Fluvial Bed Sediments, and Fluvial Flood Deposit Sediments from the Big River and Meramec River Drainage Basins, Missouri Geochemical Analyses of Water, Mine tailings, Fluvial Suspended Sediments, Fluvial Bed Sediments, and Fluvial Flood Deposit Sediments from the Big River and Meramec River Drainage Basins, Missouri

Geochemical data for aqueous, mine tailings, and sediment samples collected from the Big River and Meramec River drainage basins in southeastern Missouri are presented. The Big River drains historical lead, zinc, and barite mining districts, including the Old Lead Belt (OLB). Underground mining in the OLB resulted in large mine-waste chat piles and tailings impoundments that have...
By
Central Midwest Water Science Center

Modeled Pacific salmon escapement biomass and nutrient and contaminant concentrations across western North America, 1976-2015 (version 2.0, October 2024) Modeled Pacific salmon escapement biomass and nutrient and contaminant concentrations across western North America, 1976-2015 (version 2.0, October 2024)

The data contain yearly modeled estimates of Pacific salmon escapement (in annual metric tons of wet mass) from 1976 to 2015 across four regions of western North America. A second data file contains modeled estimates of contaminant or nutrient concentrations in Pacific Salmon. The modeled estimates were derived from Bayesian generalized linear models (contaminant or nutrient...
By
Columbia Environmental Research Center

Total mercury, methylmercury, and isotopic composition in various life stages of boreal chorus frogs (Pseudacris maculata) at two subalpine ponds in the Rocky Mountains, CO, USA, 2015 Total mercury, methylmercury, and isotopic composition in various life stages of boreal chorus frogs (Pseudacris maculata) at two subalpine ponds in the Rocky Mountains, CO, USA, 2015

Mercury is an atmospherically transported contaminant found even in relatively pristine habitats. Once accumulated at the base of the food web, mercury can move between animals that are linked trophically. Pond-breeding amphibians may be particularly important vectors of mercury flux from remote freshwater to terrestrial systems because they feed on algae and detritus as tadpoles and...
By
Columbia Environmental Research Center

Mercury concentrations, isotopic composition, biomass, and taxonomy of stream and riparian organisms in the vicinity of Yellow Pine, Idaho, 2015-2016. Mercury concentrations, isotopic composition, biomass, and taxonomy of stream and riparian organisms in the vicinity of Yellow Pine, Idaho, 2015-2016.

This data release includes sampling location data; field-collected stream attribute data; laboratory-analyzed chemistry concentrations (total mercury, methyl mercury) and isotopic composition (total mercury, carbon, and nitrogen) for stream biota (seston, periphyton, benthic insects, emerging adult insects, riparian spiders, and fish); density, body length, and taxonomic information for...
By
Mineral Resources Program, Columbia Environmental Research Center, Geology, Geophysics, and Geochemistry Science Center

Dataset for temporal influences on selenium partitioning, trophic transfer, and exposure in a major U.S. river Dataset for temporal influences on selenium partitioning, trophic transfer, and exposure in a major U.S. river

The trace element selenium is an essential element with a narrow window between concentrations needed to support life and those that cause toxicity to egg laying organisms. Selenium bioaccumulation in aquatic organisms is primarily the result of trophic transfer through food webs and is poorly predicted by dissolved concentrations in freshwater bodies. To better understand the hydrologic...
By
Wyoming-Montana Water Science Center
Filter Total Items: 22

Continental-scale nutrient and contaminant delivery by Pacific salmon Continental-scale nutrient and contaminant delivery by Pacific salmon

The movement of large amounts of nutrients by migrating animals has ecological benefits for recipient food webs1,2 that may be offset by co-transported contaminants3,4. Salmon spawning migrations are archetypal of this process, carrying marine-derived materials to inland ecosystems where they stimulate local productivity but also enhance contaminant exposure5,6,7. Pacific salmon...
Authors
Jessica E. Brandt, Jeff S. Wesner, Gregory T. Ruggerone, Timothy D. Jardine, Collin A. Eagles-Smith, Gabrielle E. Ruso, Craig A. Stricker, Cristofor A. Voss, David Walters
By
Ecosystems Mission Area, Columbia Environmental Research Center

Complex life histories alter patterns of mercury exposure and accumulation in a pond-breeding amphibian Complex life histories alter patterns of mercury exposure and accumulation in a pond-breeding amphibian

Quantifying how contaminants change across life cycles of species that undergo metamorphosis is critical to assessing organismal risk, particularly for consumers. Pond-breeding amphibians can dominate aquatic animal biomass as larvae and are terrestrial prey as juveniles and adults. Thus, amphibians can be vectors of mercury exposure in both aquatic and terrestrial food webs. However, it...
Authors
Freya Elizabeth Rowland, Erin L. Muths, Collin A. Eagles-Smith, Craig A. Stricker, Johanna M. Kraus, Rachel A. Harrington, David Walters
By
Ecosystems Mission Area, Columbia Environmental Research Center, Fort Collins Science Center

Increased mercury and reduced insect diversity in linked stream-riparian food webs downstream of a historical mercury mine Increased mercury and reduced insect diversity in linked stream-riparian food webs downstream of a historical mercury mine

Historical mining left a legacy of abandoned mines and waste rock in remote headwaters of major river systems in the western United States. Understanding the influence of these legacy mines on culturally and ecological important downstream ecosystems is not always straight-forward because of elevated natural levels of mineralization in mining-impacted watersheds. To test the ecological...
Authors
Johanna M. Kraus, JoAnn M. Holloway, Michael J. Pribil, Ben N. Mcgee, Craig A. Stricker, Danny Rutherford, Andrew S. Todd
By
Ecosystems Mission Area, Columbia Environmental Research Center

Temporal influences on selenium partitioning, trophic transfer, and exposure in a major U.S. river Temporal influences on selenium partitioning, trophic transfer, and exposure in a major U.S. river

Hydrologic and irrigation regimes mediate the timing of selenium (Se) mobilization to rivers, but the extent to which patterns in Se uptake and trophic transfer through recipient food webs reflect the temporal variation in Se delivery is unknown. We investigated Se mobilization, partitioning, and trophic transfer along approximately 60 river miles of the selenium-impaired segment of the...
Authors
Jessica E Brandt, James Roberts, Craig A. Stricker, Holly Rogers, Patricia Nease, Travis S. Schmidt
By
Ecosystems Mission Area, Water Resources Mission Area, Fort Collins Science Center, Great Lakes Science Center, Wyoming-Montana Water Science Center

Short- and long-term responses of riparian cottonwoods (Populus spp.) to flow diversion: Analysis of tree-ring radial growth and stable carbon isotopes Short- and long-term responses of riparian cottonwoods (Populus spp.) to flow diversion: Analysis of tree-ring radial growth and stable carbon isotopes

Long duration tree-ring records with annual precision allow for the reconstruction of past growing conditions. Investigations limited to the most common tree-ring proxy of ring width can be difficult to interpret, however, because radial growth is affected by multiple environmental processes. Furthermore, studies of living trees may miss important effects of drought on tree survival and...
Authors
Derek M. Schook, Jonathan M. Friedman, Craig A. Stricker, Adam Z. Csank, David J. Cooper
By
Ecosystems Mission Area, Fort Collins Science Center

Juvenile Coho and Chinook salmon growth, size, and condition linked to watershed-scale salmon spawner abundance Juvenile Coho and Chinook salmon growth, size, and condition linked to watershed-scale salmon spawner abundance

Anadromous Pacific salmon Oncorhynchus spp. are semelparous, and resource subsidies from spawning adult salmon (marine-derived nutrients [MDN]) benefit juvenile salmonids while they rear in freshwater. However, it is unclear if juvenile salmon populations respond predictably to the abundance of spawning salmon at the watershed scale. To address whether hypothesized benefits to rearing...
Authors
Philip J. Joy, Craig A. Stricker, Renae Ivanoff, Shiao Y. Wang, Mark S. Wipfli, Andrew C. Seitz, Jiaqi Huang, Mathew B. Tyers
By
Ecosystems Mission Area, Cooperative Research Units, Fort Collins Science Center

Biogeochemical cycles impart significant control on ecosystem structure, function, and ecosystem services, such as nutrient sequestration, transformation, long-term storage, mitigation of water quality concerns, and carbon fixation/mineralization processes that support local food webs. 

Return to the GSIL Homepage
Media
a gloved hand holds four capped test tubes containing brown liquids, blue door in background
Sources/Usage: Public Domain. View Media Details
Extracts of lignon phenol from peat in the Great Dismal Swamp

Isotope geochemistry offers novel insight into sources, processes, and fates of a broad array of elements that are relevant to ecosystem science. These geochemical insights also integrate well with food web studies, offering a more complete assessment of critical nutrient sources, fixation, and ultimately secondary production. 

This project includes studies that explicitly focus on elements (for example, carbon, nitrogen, sulfur) that have strong linkages between geochemical compartments and biological production (for example, nutrient sources/fates, decomposition, carbon fixation, food webs) as well as related processes for non-essential elements (for example, bioaccumulation) and long-term storage/permanence important to ecosystem function and persistence (for example, soil carbon). The latter also includes studies of natural environmental archives (for example, tree rings, sediments) that inform on historical and contemporary ecosystem health with the goal of aiding conservation and management. 

Media
a swampy wetland with dead tree trunks coming up from the water, cloudy skies
Sources/Usage: Public Domain. View Media Details
USGS scientists and collaborators investigated the effects of disturbance on peatland carbon chemistry in the Great Dismal Swamp, which has experienced fires, drought-like conditions, and other major disturbances over the last 200 years. Read more.
a laboratory space containing technical equipment, drawers, desks, and chairs

Geology, Geophysics, and Geochemistry Stable Isotope Laboratory (GSIL)

The GSIL is a state-of-the-art facility located on the Denver Federal Center that specializes in the measurement of light stable isotope — Hydrogen (H), Carbon (C), Nitrogen (N), Oxygen (O), and Sulfur (S) — compositions and other chemical and biomarker analytes in matrices relevant to the Earth sciences. Chemical and isotopic tracers offer novel insights into ecosystem biogeochemistry, food webs...
By
Fort Collins Science Center, Geology, Geophysics, and Geochemistry Science Center
Geology, Geophysics, and Geochemistry Stable Isotope Laboratory (GSIL)

Geology, Geophysics, and Geochemistry Stable Isotope Laboratory (GSIL)

The GSIL is a state-of-the-art facility located on the Denver Federal Center that specializes in the measurement of light stable isotope — Hydrogen (H), Carbon (C), Nitrogen (N), Oxygen (O), and Sulfur (S) — compositions and other chemical and biomarker analytes in matrices relevant to the Earth sciences. Chemical and isotopic tracers offer novel insights into ecosystem biogeochemistry, food webs...
Learn More
Polar bear mother and two cubs on the Beaufort Sea ice.

Food Webs and Wildlife Nutrition

Wildlife nutrition is an essential element of fitness, and contextualizing resource use within the broader framework of local and regional food webs is paramount to species health, function, and management.
By
Fort Collins Science Center
Food Webs and Wildlife Nutrition

Food Webs and Wildlife Nutrition

Wildlife nutrition is an essential element of fitness, and contextualizing resource use within the broader framework of local and regional food webs is paramount to species health, function, and management.
Learn More
Breeding colony of terns on Breton Island

Wildlife Biogeography

The distribution of species across the landscape is of great interest to biologists, owing to a critical need to understand the connectivity of disparate habitats for species that undertake broadscale movements. Indeed, habitat quality and quantity are thought to be important drivers of occurrence and distribution, and numerous studies have demonstrated fitness-related consequences as evidenced in...
By
Fort Collins Science Center
Wildlife Biogeography

Wildlife Biogeography

The distribution of species across the landscape is of great interest to biologists, owing to a critical need to understand the connectivity of disparate habitats for species that undertake broadscale movements. Indeed, habitat quality and quantity are thought to be important drivers of occurrence and distribution, and numerous studies have demonstrated fitness-related consequences as evidenced in...
Learn More
Two scientists work on a study of mercury contamination in the water.

Environmental Stressors

Environmental stressors that impact habitat and wildlife species include: abiotic factors (for example, land use, temperature); soil, air, and water quality (for example, eutrophication, contaminants); and disturbance (for example, fire, drought, hurricanes, species invasions). Understanding how these stressors impact ecosystems is critical to conservation and management.
By
Fort Collins Science Center
Environmental Stressors

Environmental Stressors

Environmental stressors that impact habitat and wildlife species include: abiotic factors (for example, land use, temperature); soil, air, and water quality (for example, eutrophication, contaminants); and disturbance (for example, fire, drought, hurricanes, species invasions). Understanding how these stressors impact ecosystems is critical to conservation and management.
Learn More

Water chemistry, stable isotopes, and trace metals in sediment, water and biota in Torch Lake and Gratiot Lake, Keweenaw Peninsula, Michigan, USA, July and October 2021 Water chemistry, stable isotopes, and trace metals in sediment, water and biota in Torch Lake and Gratiot Lake, Keweenaw Peninsula, Michigan, USA, July and October 2021

This data release includes sampling location data, laboratory processed surface water chemistry data (anions, cations, total nitrogen, dissolved organic carbon, deuterium, trace metals), laboratory processed pore water chemistry data (anions, cations, total nitrogen, dissolved organic carbon, trace metals), laboratory process sediment data (trace metals), and whole-body trace metal...
By
Columbia Environmental Research Center

Geochemical Analyses of Water, Mine tailings, Fluvial Suspended Sediments, Fluvial Bed Sediments, and Fluvial Flood Deposit Sediments from the Big River and Meramec River Drainage Basins, Missouri Geochemical Analyses of Water, Mine tailings, Fluvial Suspended Sediments, Fluvial Bed Sediments, and Fluvial Flood Deposit Sediments from the Big River and Meramec River Drainage Basins, Missouri

Geochemical data for aqueous, mine tailings, and sediment samples collected from the Big River and Meramec River drainage basins in southeastern Missouri are presented. The Big River drains historical lead, zinc, and barite mining districts, including the Old Lead Belt (OLB). Underground mining in the OLB resulted in large mine-waste chat piles and tailings impoundments that have...
By
Central Midwest Water Science Center

Modeled Pacific salmon escapement biomass and nutrient and contaminant concentrations across western North America, 1976-2015 (version 2.0, October 2024) Modeled Pacific salmon escapement biomass and nutrient and contaminant concentrations across western North America, 1976-2015 (version 2.0, October 2024)

The data contain yearly modeled estimates of Pacific salmon escapement (in annual metric tons of wet mass) from 1976 to 2015 across four regions of western North America. A second data file contains modeled estimates of contaminant or nutrient concentrations in Pacific Salmon. The modeled estimates were derived from Bayesian generalized linear models (contaminant or nutrient...
By
Columbia Environmental Research Center

Total mercury, methylmercury, and isotopic composition in various life stages of boreal chorus frogs (Pseudacris maculata) at two subalpine ponds in the Rocky Mountains, CO, USA, 2015 Total mercury, methylmercury, and isotopic composition in various life stages of boreal chorus frogs (Pseudacris maculata) at two subalpine ponds in the Rocky Mountains, CO, USA, 2015

Mercury is an atmospherically transported contaminant found even in relatively pristine habitats. Once accumulated at the base of the food web, mercury can move between animals that are linked trophically. Pond-breeding amphibians may be particularly important vectors of mercury flux from remote freshwater to terrestrial systems because they feed on algae and detritus as tadpoles and...
By
Columbia Environmental Research Center

Mercury concentrations, isotopic composition, biomass, and taxonomy of stream and riparian organisms in the vicinity of Yellow Pine, Idaho, 2015-2016. Mercury concentrations, isotopic composition, biomass, and taxonomy of stream and riparian organisms in the vicinity of Yellow Pine, Idaho, 2015-2016.

This data release includes sampling location data; field-collected stream attribute data; laboratory-analyzed chemistry concentrations (total mercury, methyl mercury) and isotopic composition (total mercury, carbon, and nitrogen) for stream biota (seston, periphyton, benthic insects, emerging adult insects, riparian spiders, and fish); density, body length, and taxonomic information for...
By
Mineral Resources Program, Columbia Environmental Research Center, Geology, Geophysics, and Geochemistry Science Center

Dataset for temporal influences on selenium partitioning, trophic transfer, and exposure in a major U.S. river Dataset for temporal influences on selenium partitioning, trophic transfer, and exposure in a major U.S. river

The trace element selenium is an essential element with a narrow window between concentrations needed to support life and those that cause toxicity to egg laying organisms. Selenium bioaccumulation in aquatic organisms is primarily the result of trophic transfer through food webs and is poorly predicted by dissolved concentrations in freshwater bodies. To better understand the hydrologic...
By
Wyoming-Montana Water Science Center
Filter Total Items: 22

Continental-scale nutrient and contaminant delivery by Pacific salmon Continental-scale nutrient and contaminant delivery by Pacific salmon

The movement of large amounts of nutrients by migrating animals has ecological benefits for recipient food webs1,2 that may be offset by co-transported contaminants3,4. Salmon spawning migrations are archetypal of this process, carrying marine-derived materials to inland ecosystems where they stimulate local productivity but also enhance contaminant exposure5,6,7. Pacific salmon...
Authors
Jessica E. Brandt, Jeff S. Wesner, Gregory T. Ruggerone, Timothy D. Jardine, Collin A. Eagles-Smith, Gabrielle E. Ruso, Craig A. Stricker, Cristofor A. Voss, David Walters
By
Ecosystems Mission Area, Columbia Environmental Research Center

Complex life histories alter patterns of mercury exposure and accumulation in a pond-breeding amphibian Complex life histories alter patterns of mercury exposure and accumulation in a pond-breeding amphibian

Quantifying how contaminants change across life cycles of species that undergo metamorphosis is critical to assessing organismal risk, particularly for consumers. Pond-breeding amphibians can dominate aquatic animal biomass as larvae and are terrestrial prey as juveniles and adults. Thus, amphibians can be vectors of mercury exposure in both aquatic and terrestrial food webs. However, it...
Authors
Freya Elizabeth Rowland, Erin L. Muths, Collin A. Eagles-Smith, Craig A. Stricker, Johanna M. Kraus, Rachel A. Harrington, David Walters
By
Ecosystems Mission Area, Columbia Environmental Research Center, Fort Collins Science Center

Increased mercury and reduced insect diversity in linked stream-riparian food webs downstream of a historical mercury mine Increased mercury and reduced insect diversity in linked stream-riparian food webs downstream of a historical mercury mine

Historical mining left a legacy of abandoned mines and waste rock in remote headwaters of major river systems in the western United States. Understanding the influence of these legacy mines on culturally and ecological important downstream ecosystems is not always straight-forward because of elevated natural levels of mineralization in mining-impacted watersheds. To test the ecological...
Authors
Johanna M. Kraus, JoAnn M. Holloway, Michael J. Pribil, Ben N. Mcgee, Craig A. Stricker, Danny Rutherford, Andrew S. Todd
By
Ecosystems Mission Area, Columbia Environmental Research Center

Temporal influences on selenium partitioning, trophic transfer, and exposure in a major U.S. river Temporal influences on selenium partitioning, trophic transfer, and exposure in a major U.S. river

Hydrologic and irrigation regimes mediate the timing of selenium (Se) mobilization to rivers, but the extent to which patterns in Se uptake and trophic transfer through recipient food webs reflect the temporal variation in Se delivery is unknown. We investigated Se mobilization, partitioning, and trophic transfer along approximately 60 river miles of the selenium-impaired segment of the...
Authors
Jessica E Brandt, James Roberts, Craig A. Stricker, Holly Rogers, Patricia Nease, Travis S. Schmidt
By
Ecosystems Mission Area, Water Resources Mission Area, Fort Collins Science Center, Great Lakes Science Center, Wyoming-Montana Water Science Center

Short- and long-term responses of riparian cottonwoods (Populus spp.) to flow diversion: Analysis of tree-ring radial growth and stable carbon isotopes Short- and long-term responses of riparian cottonwoods (Populus spp.) to flow diversion: Analysis of tree-ring radial growth and stable carbon isotopes

Long duration tree-ring records with annual precision allow for the reconstruction of past growing conditions. Investigations limited to the most common tree-ring proxy of ring width can be difficult to interpret, however, because radial growth is affected by multiple environmental processes. Furthermore, studies of living trees may miss important effects of drought on tree survival and...
Authors
Derek M. Schook, Jonathan M. Friedman, Craig A. Stricker, Adam Z. Csank, David J. Cooper
By
Ecosystems Mission Area, Fort Collins Science Center

Juvenile Coho and Chinook salmon growth, size, and condition linked to watershed-scale salmon spawner abundance Juvenile Coho and Chinook salmon growth, size, and condition linked to watershed-scale salmon spawner abundance

Anadromous Pacific salmon Oncorhynchus spp. are semelparous, and resource subsidies from spawning adult salmon (marine-derived nutrients [MDN]) benefit juvenile salmonids while they rear in freshwater. However, it is unclear if juvenile salmon populations respond predictably to the abundance of spawning salmon at the watershed scale. To address whether hypothesized benefits to rearing...
Authors
Philip J. Joy, Craig A. Stricker, Renae Ivanoff, Shiao Y. Wang, Mark S. Wipfli, Andrew C. Seitz, Jiaqi Huang, Mathew B. Tyers
By
Ecosystems Mission Area, Cooperative Research Units, Fort Collins Science Center
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