Jennifer Harden, PhD (Former Employee)
Science and Products
Filter Total Items: 134
Bacterial and enchytraeid abundance accelerate soil carbon turnover along a lowland vegetation gradient in interior Alaska
Boreal wetlands are characterized by a mosaic of plant communities, including forests, shrublands, grasslands, and fens, which are structured largely by changes in topography and water table position. The soil associated with these plant communities contain quantitatively and qualitatively different forms of soil organic matter (SOM) and nutrient availability that drive changes in biogeochemical c
Authors
M. P. Waldrop, Jennifer W. Harden, M.R. Turetsky, D.G. Petersen, A. D. McGuire, M.J.I. Briones, A.C. Churchill, D.H. Doctor, L.E. Pruett
The effects of permafrost thaw on soil hydrologic, thermal, and carbon dynamics in an Alaskan peatland
Recent warming at high-latitudes has accelerated permafrost thaw in northern peatlands, and thaw can have profound effects on local hydrology and ecosystem carbon balance. To assess the impact of permafrost thaw on soil organic carbon (OC) dynamics, we measured soil hydrologic and thermal dynamics and soil OC stocks across a collapse-scar bog chronosequence in interior Alaska. We observed dramatic
Authors
Jonathan A. O'Donnell, M. Torre Jorgenson, Jennifer W. Harden, A. David McGuire, Mikhail Z. Kanevskiy, Kimberly P. Wickland
Spatiotemporal analysis of black spruce forest soils and implications for the fate of C
Post-fire storage of carbon (C) in organic-soil horizons was measured in one Canadian and three Alaskan chronosequences in black spruce forests, together spanning stand ages of nearly 200 yrs. We used a simple mass balance model to derive estimates of inputs, losses, and accumulation rates of C on timescales of years to centuries. The model performed well for the surface and total organic soil lay
Authors
Jennifer W. Harden, Kristen L. Manies, Jonathan O'Donnell, Kristofer Johnson, Steve Frolking, Zhaosheng Fan
Photodissolution of soil organic matter
Sunlight has been shown to enhance loss of organic matter from aquatic sediments and terrestrial plant litter, so we tested for similar reactions in mineral soil horizons. Losses of up to a third of particulate organic carbon occurred after continuous exposure to full-strength sunlight for dozens of hours, with similar amounts appearing as photodissolved organic carbon. Nitrogen dissolved similarl
Authors
L.M. Mayer, K.R. Thornton, L.L. Schick, J.D. Jastrow, Jennifer W. Harden
Water and heat transport in boreal soils: Implications for soil response to climate change
Soil water content strongly affects permafrost dynamics by changing the soil thermal properties. However, the movement of liquid water, which plays an important role in the heat transport of temperate soils, has been under-represented in boreal studies. Two different heat transport models with and without convective heat transport were compared to measurements of soil temperatures in four boreal s
Authors
Zhaosheng Fan, Jennifer W. Harden, G.C. Winston, Jonathan A. O'Donnell, Jason C. Neff, Tingjun Zhang, Hugo Veldhuis, C.I. Czimczik
Soils Data Related to the 1999 FROSTFIRE Burn
This report describes the sample collection and processing for U.S. Geological Survey efforts at FROSTFIRE, an experimental burn that occurred in Alaska in 1999. Data regarding carbon, water, and energy dynamics pre-fire, during, and post-fire were obtained in this landscape-scale prescribed burn. U.S. Geological Survey investigators measured changes in the stocks of carbon (C), nitrogen (N), merc
Authors
K.L. Manies, J. W. Harden, R. Ottmar
Vulnerability of high-latitude soil organic carbon in North America to disturbance
This synthesis addresses the vulnerability of the North American high-latitude soil organic carbon (SOC) pool to climate change. Disturbances caused by climate warming in arctic, subarctic, and boreal environments can result in significant redistribution of C among major reservoirs with potential global impacts. We divide the current northern high-latitude SOC pools into (1) near-surface soils whe
Authors
Guido Grosse, Jennifer W. Harden, Merritt Turetsky, A. David McGuire, Philip Camill, Charles Tarnocai, Steve Frolking, Edward A.G. Schuur, Torre Jorgenson, Sergei Marchenko, Vladimir Romanovsky, Kimberly P. Wickland, Nancy French, Mark P. Waldrop, Laura L. Bourgeau-Chavez, Robert G. Striegl
Soil physical, chemical, and gas-flux characterization from Picea mariana stands near Erickson Creek, Alaska
Fire is a particularly important control on the carbon (C) balance of the boreal forest, and fire-return intervals and fire severity appear to have increased since the late 1900s in North America. In addition to the immediate release of stored C to the atmosphere through organic-matter combustion, fire also modifies soil conditions, possibly affecting C exchange between terrestrial and atmospheric
Authors
Jonathan A. O'Donnell, Jennifer W. Harden, Kristen L. Manies
Soil data from different-age Picea mariana stands near Delta Junction, Alaska
One objective of the U.S. Geological Survey\'s Fate of Carbon in Alaskan Landscapes (FOCAL) project is to study the effects of fire and soil drainage on soil carbon storage in boreal forests. For this purpose, the project has measured the soil carbon content in several chronosequences (time since disturbance) of various soil-drainage types. One such chronosequence near Delta Junction, Alaska was i
Authors
Kristen L. Manies, Jennifer W. Harden
Patterns of NPP, GPP, respiration, and NEP during boreal forest succession
We combined year‐round eddy covariance with biometry and biomass harvests along a chronosequence of boreal forest stands that were 1, 6, 15, 23, 40, ∼74, and ∼154 years old to understand how ecosystem production and carbon stocks change during recovery from stand‐replacing crown fire. Live biomass (Clive) was low in the 1‐ and 6‐year‐old stands, and increased following a logistic pattern to high l
Authors
M. L. Goulden, A.M.S. Mcmillan, G.C. Winston, A.V. Rocha, K.L. Manies, J. W. Harden, B. P. Bond-Lamberty
Exploring the sensitivity of soil carbon dynamics to climate change, fire disturbance and permafrost thaw in a black spruce ecosystem
In the boreal region, soil organic carbon (OC) dynamics are strongly governed by the interaction between wildfire and permafrost. Using a combination of field measurements, numerical modeling of soil thermal dynamics, and mass-balance modeling of OC dynamics, we tested the sensitivity of soil OC storage to a suite of individual climate factors (air temperature, soil moisture, and snow depth) and f
Authors
J. A. O'Donnell, Jennifer W. Harden, A. David McGuire, V.E. Romanovsky
The effect of fire and permafrost interactions on soil carbon accumulation in an upland black spruce ecosystem of interior Alaska: Implications for post-thaw carbon loss
High‐latitude regions store large amounts of organic carbon (OC) in active‐layer soils and permafrost, accounting for nearly half of the global belowground OC pool. In the boreal region, recent warming has promoted changes in the fire regime, which may exacerbate rates of permafrost thaw and alter soil OC dynamics in both organic and mineral soil. We examined how interactions between fire and perm
Authors
J. A. O'Donnell, J. W. Harden, A. D. McGuire, M.Z. Kanevskiy, M.T. Jorgenson, X. Xu
Science and Products
Filter Total Items: 134
Bacterial and enchytraeid abundance accelerate soil carbon turnover along a lowland vegetation gradient in interior Alaska
Boreal wetlands are characterized by a mosaic of plant communities, including forests, shrublands, grasslands, and fens, which are structured largely by changes in topography and water table position. The soil associated with these plant communities contain quantitatively and qualitatively different forms of soil organic matter (SOM) and nutrient availability that drive changes in biogeochemical c
Authors
M. P. Waldrop, Jennifer W. Harden, M.R. Turetsky, D.G. Petersen, A. D. McGuire, M.J.I. Briones, A.C. Churchill, D.H. Doctor, L.E. Pruett
The effects of permafrost thaw on soil hydrologic, thermal, and carbon dynamics in an Alaskan peatland
Recent warming at high-latitudes has accelerated permafrost thaw in northern peatlands, and thaw can have profound effects on local hydrology and ecosystem carbon balance. To assess the impact of permafrost thaw on soil organic carbon (OC) dynamics, we measured soil hydrologic and thermal dynamics and soil OC stocks across a collapse-scar bog chronosequence in interior Alaska. We observed dramatic
Authors
Jonathan A. O'Donnell, M. Torre Jorgenson, Jennifer W. Harden, A. David McGuire, Mikhail Z. Kanevskiy, Kimberly P. Wickland
Spatiotemporal analysis of black spruce forest soils and implications for the fate of C
Post-fire storage of carbon (C) in organic-soil horizons was measured in one Canadian and three Alaskan chronosequences in black spruce forests, together spanning stand ages of nearly 200 yrs. We used a simple mass balance model to derive estimates of inputs, losses, and accumulation rates of C on timescales of years to centuries. The model performed well for the surface and total organic soil lay
Authors
Jennifer W. Harden, Kristen L. Manies, Jonathan O'Donnell, Kristofer Johnson, Steve Frolking, Zhaosheng Fan
Photodissolution of soil organic matter
Sunlight has been shown to enhance loss of organic matter from aquatic sediments and terrestrial plant litter, so we tested for similar reactions in mineral soil horizons. Losses of up to a third of particulate organic carbon occurred after continuous exposure to full-strength sunlight for dozens of hours, with similar amounts appearing as photodissolved organic carbon. Nitrogen dissolved similarl
Authors
L.M. Mayer, K.R. Thornton, L.L. Schick, J.D. Jastrow, Jennifer W. Harden
Water and heat transport in boreal soils: Implications for soil response to climate change
Soil water content strongly affects permafrost dynamics by changing the soil thermal properties. However, the movement of liquid water, which plays an important role in the heat transport of temperate soils, has been under-represented in boreal studies. Two different heat transport models with and without convective heat transport were compared to measurements of soil temperatures in four boreal s
Authors
Zhaosheng Fan, Jennifer W. Harden, G.C. Winston, Jonathan A. O'Donnell, Jason C. Neff, Tingjun Zhang, Hugo Veldhuis, C.I. Czimczik
Soils Data Related to the 1999 FROSTFIRE Burn
This report describes the sample collection and processing for U.S. Geological Survey efforts at FROSTFIRE, an experimental burn that occurred in Alaska in 1999. Data regarding carbon, water, and energy dynamics pre-fire, during, and post-fire were obtained in this landscape-scale prescribed burn. U.S. Geological Survey investigators measured changes in the stocks of carbon (C), nitrogen (N), merc
Authors
K.L. Manies, J. W. Harden, R. Ottmar
Vulnerability of high-latitude soil organic carbon in North America to disturbance
This synthesis addresses the vulnerability of the North American high-latitude soil organic carbon (SOC) pool to climate change. Disturbances caused by climate warming in arctic, subarctic, and boreal environments can result in significant redistribution of C among major reservoirs with potential global impacts. We divide the current northern high-latitude SOC pools into (1) near-surface soils whe
Authors
Guido Grosse, Jennifer W. Harden, Merritt Turetsky, A. David McGuire, Philip Camill, Charles Tarnocai, Steve Frolking, Edward A.G. Schuur, Torre Jorgenson, Sergei Marchenko, Vladimir Romanovsky, Kimberly P. Wickland, Nancy French, Mark P. Waldrop, Laura L. Bourgeau-Chavez, Robert G. Striegl
Soil physical, chemical, and gas-flux characterization from Picea mariana stands near Erickson Creek, Alaska
Fire is a particularly important control on the carbon (C) balance of the boreal forest, and fire-return intervals and fire severity appear to have increased since the late 1900s in North America. In addition to the immediate release of stored C to the atmosphere through organic-matter combustion, fire also modifies soil conditions, possibly affecting C exchange between terrestrial and atmospheric
Authors
Jonathan A. O'Donnell, Jennifer W. Harden, Kristen L. Manies
Soil data from different-age Picea mariana stands near Delta Junction, Alaska
One objective of the U.S. Geological Survey\'s Fate of Carbon in Alaskan Landscapes (FOCAL) project is to study the effects of fire and soil drainage on soil carbon storage in boreal forests. For this purpose, the project has measured the soil carbon content in several chronosequences (time since disturbance) of various soil-drainage types. One such chronosequence near Delta Junction, Alaska was i
Authors
Kristen L. Manies, Jennifer W. Harden
Patterns of NPP, GPP, respiration, and NEP during boreal forest succession
We combined year‐round eddy covariance with biometry and biomass harvests along a chronosequence of boreal forest stands that were 1, 6, 15, 23, 40, ∼74, and ∼154 years old to understand how ecosystem production and carbon stocks change during recovery from stand‐replacing crown fire. Live biomass (Clive) was low in the 1‐ and 6‐year‐old stands, and increased following a logistic pattern to high l
Authors
M. L. Goulden, A.M.S. Mcmillan, G.C. Winston, A.V. Rocha, K.L. Manies, J. W. Harden, B. P. Bond-Lamberty
Exploring the sensitivity of soil carbon dynamics to climate change, fire disturbance and permafrost thaw in a black spruce ecosystem
In the boreal region, soil organic carbon (OC) dynamics are strongly governed by the interaction between wildfire and permafrost. Using a combination of field measurements, numerical modeling of soil thermal dynamics, and mass-balance modeling of OC dynamics, we tested the sensitivity of soil OC storage to a suite of individual climate factors (air temperature, soil moisture, and snow depth) and f
Authors
J. A. O'Donnell, Jennifer W. Harden, A. David McGuire, V.E. Romanovsky
The effect of fire and permafrost interactions on soil carbon accumulation in an upland black spruce ecosystem of interior Alaska: Implications for post-thaw carbon loss
High‐latitude regions store large amounts of organic carbon (OC) in active‐layer soils and permafrost, accounting for nearly half of the global belowground OC pool. In the boreal region, recent warming has promoted changes in the fire regime, which may exacerbate rates of permafrost thaw and alter soil OC dynamics in both organic and mineral soil. We examined how interactions between fire and perm
Authors
J. A. O'Donnell, J. W. Harden, A. D. McGuire, M.Z. Kanevskiy, M.T. Jorgenson, X. Xu
*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