Jennifer Harden, PhD (Former Employee)
Science and Products
Filter Total Items: 134
Soil Data from a Moderately Well and Somewhat Poorly Drained Fire Chronosequence near Thompson, Manitoba, Canada
The U.S. Geological Survey project Fate of Carbon in Alaskan Landscapes (FOCAL) is studying the effect of fire and soil drainage on soil carbon storage in the boreal forest. As such this group was invited to be a part of a NSF-funded project (Fire, Ecosystem and Succession - Experiment Boreal or FIRES-ExB) to study the carbon balance of sites that varied in age (time since fire) and soil drainage
Authors
K.L. Manies, J. W. Harden, Hugo Veldhuis, Sue Trumbore
Reconciling carbon-cycle concepts, terminology, and methods
Recent projections of climatic change have focused a great deal of scientific and public attention on patterns of carbon (C) cycling as well as its controls, particularly the factors that determine whether an ecosystem is a net source or sink of atmospheric carbon dioxide (CO2). Net ecosystem production (NEP), a central concept in C-cycling research, has been used by scientists to represent two di
Authors
F. S. Chapin, G. M. Woodwell, J. T. Randerson, E. B. Rastetter, G. Lovett, D. D. Baldocchi, D. A. Clark, M. E. Harmon, D. S. Schimel, R. Valentini, C. Wirth, J. D. Aber, J. J. Cole, M. L. Goulden, Jennifer W. Harden, M. Heimann, R. W. Howarth, P. A. Matson, A. D. McGuire, J. M. Melillo, H. A. Mooney, J. C. Neff, R. A. Houghton, M. L. Pace, M. G. Ryan, S. W. Running, O. E. Sala, W. H. Schlesinger, E. -D. Schulze
Stable carbon isotope depth profiles and soil organic carbon dynamics in the lower Mississippi Basin
Analysis of depth trends of 13C abundance in soil organic matter and of 13C abundance from soil-respired CO2 provides useful indications of the dynamics of the terrestrial carbon cycle and of paleoecological change. We measured depth trends of 13C abundance from cropland and control pairs of soils in the lower Mississippi Basin, as well as the 13C abundance of soil-respired CO2 produced during app
Authors
J.G. Wynn, J. W. Harden, T. L. Fries
Modeling physical and biogeochemical controls over carbon accumulation in a boreal forest soil
Boreal soils are important to the global C cycle owing to large C stocks, repeated disturbance from fire, and the potential for permafrost thaw to expose previously stable, buried C. To evaluate the primary mechanisms responsible for both short- and long-term C accumulation in boreal soils, we developed a multi-isotope (12,14C) Soil C model with dynamic soil layers that develop through time as soi
Authors
J.J. Carrasco, J. C. Neff, J. W. Harden
The impact of boreal forest fire on climate warming
We report measurements and analysis of a boreal forest fire, integrating the effects of greenhouse gases, aerosols, black carbon deposition on snow and sea ice, and postfire changes in surface albedo. The net effect of all agents was to increase radiative forcing during the first year (34 ?? 31 Watts per square meter of burned area), but to decrease radiative forcing when averaged over an 80-year
Authors
J. T. Randerson, H. Liu, M.G. Flanner, S.D. Chambers, Y. Jin, P.G. Hess, G. Pfister, M.C. Mack, K.K. Treseder, L.R. Welp, F.S. Chapin, J. W. Harden, M. L. Goulden, E. Lyons, J. C. Neff, E.A.G. Schuur, C.S. Zender
Geomorphic control of landscape carbon accumulation
We use the CREEP process-response model to simulate soil organic carbon accumulation in an undisturbed prairie site in Iowa. Our primary objectives are to identify spatial patterns of carbon accumulation, and explore the effect of erosion on basin-scale C accumulation. Our results point to two general findings. First, redistribution of soil carbon by erosion results in a net increase in basin-wide
Authors
N.A. Rosenbloom, J. W. Harden, J. C. Neff, D. S. Schimel
Wildfires threaten mercury stocks in northern soils
With climate change rapidly affecting northern forests and wetlands, mercury reserves once protected in cold, wet soils are being exposed to burning, likely triggering large releases of mercury to the atmosphere. We quantify organic soil mercury stocks and burn areas across western, boreal Canada for use in fire emission models that explore controls of burn area, consumption severity, and fuel loa
Authors
M.R. Turetsky, J. W. Harden, H.R. Friedli, M. Flannigan, N. Payne, J. Crock, L. Radke
Effects of wildfire and permafrost on soil organic matter and soil climate in interior Alaska
The influence of discontinuous permafrost on ground-fuel storage, combustion losses, and postfire soil climates was examined after a wildfire near Delta Junction, AK in July 1999. At this site, we sampled soils from a four-way site comparison of burning (burned and unburned) and permafrost (permafrost and nonpermafrost). Soil organic layers (which comprise ground-fuel storage) were thicker in perm
Authors
J. W. Harden, K.L. Manies, M.R. Turetsky, J. C. Neff
Comparing electronic probes for volumetric water content of low-density feathermoss
Purpose - Feathermoss is ubiquitous in the boreal forest and across various land-cover types of the arctic and subarctic. A variety of affordable commercial sensors for soil moisture content measurement have recently become available and are in use in such regions, often in conjunction with fire-susceptibility or ecological studies. Few come supplied with calibrations suitable or suggested for soi
Authors
P.P. Overduin, K. Yoshikawa, D.L. Kane, J. W. Harden
Woody debris along an upland chronosequence in boreal Manitoba and its impact on long-term carbon storage
This study investigated the role of fire-killed woody debris as a source of soil carbon in black spruce (Picea mariana (Mill.) BSP) stands in Manitoba, Canada. We measured the amount of standing dead and downed woody debris along an upland chronosequence, including wood partially and completely covered by moss growth. Such woody debris is rarely included in measurement protocols and composed up to
Authors
K.L. Manies, J. W. Harden, B. P. Bond-Lamberty, K. P. O'Neill
Chemical weathering rates of a soil chronosequence on granitic alluvium: III. Hydrochemical evolution and contemporary solute fluxes and rates
Although long-term changes in solid-state compositions of soil chronosequences have been extensively investigated, this study presents the first detailed description of the concurrent hydrochemical evolution and contemporary weathering rates in such sequences. The most direct linkage between weathering and hydrology over 3 million years of soil development in the Merced chronosequence in Central C
Authors
A. F. White, M. S. Schulz, D.V. Vivit, A.E. Blum, David A. Stonestrom, J. W. Harden
Fire effects on soil organic matter content, composition, and nutrients in boreal interior Alaska
Boreal ecosystems contain a substantial fraction of the earth's soil carbon stores and are prone to frequent and severe wildfires. In this study, we examine changes in element and organic matter stocks due to a 1999 wildfire in Alaska. One year after the wildfire, burned soils contained between 1071 and 1420 g/m2 less carbon than unburned soils. Burned soils had lower nitrogen than unburned soils,
Authors
J. C. Neff, J. W. Harden, G. Gleixner
Science and Products
Filter Total Items: 134
Soil Data from a Moderately Well and Somewhat Poorly Drained Fire Chronosequence near Thompson, Manitoba, Canada
The U.S. Geological Survey project Fate of Carbon in Alaskan Landscapes (FOCAL) is studying the effect of fire and soil drainage on soil carbon storage in the boreal forest. As such this group was invited to be a part of a NSF-funded project (Fire, Ecosystem and Succession - Experiment Boreal or FIRES-ExB) to study the carbon balance of sites that varied in age (time since fire) and soil drainage
Authors
K.L. Manies, J. W. Harden, Hugo Veldhuis, Sue Trumbore
Reconciling carbon-cycle concepts, terminology, and methods
Recent projections of climatic change have focused a great deal of scientific and public attention on patterns of carbon (C) cycling as well as its controls, particularly the factors that determine whether an ecosystem is a net source or sink of atmospheric carbon dioxide (CO2). Net ecosystem production (NEP), a central concept in C-cycling research, has been used by scientists to represent two di
Authors
F. S. Chapin, G. M. Woodwell, J. T. Randerson, E. B. Rastetter, G. Lovett, D. D. Baldocchi, D. A. Clark, M. E. Harmon, D. S. Schimel, R. Valentini, C. Wirth, J. D. Aber, J. J. Cole, M. L. Goulden, Jennifer W. Harden, M. Heimann, R. W. Howarth, P. A. Matson, A. D. McGuire, J. M. Melillo, H. A. Mooney, J. C. Neff, R. A. Houghton, M. L. Pace, M. G. Ryan, S. W. Running, O. E. Sala, W. H. Schlesinger, E. -D. Schulze
Stable carbon isotope depth profiles and soil organic carbon dynamics in the lower Mississippi Basin
Analysis of depth trends of 13C abundance in soil organic matter and of 13C abundance from soil-respired CO2 provides useful indications of the dynamics of the terrestrial carbon cycle and of paleoecological change. We measured depth trends of 13C abundance from cropland and control pairs of soils in the lower Mississippi Basin, as well as the 13C abundance of soil-respired CO2 produced during app
Authors
J.G. Wynn, J. W. Harden, T. L. Fries
Modeling physical and biogeochemical controls over carbon accumulation in a boreal forest soil
Boreal soils are important to the global C cycle owing to large C stocks, repeated disturbance from fire, and the potential for permafrost thaw to expose previously stable, buried C. To evaluate the primary mechanisms responsible for both short- and long-term C accumulation in boreal soils, we developed a multi-isotope (12,14C) Soil C model with dynamic soil layers that develop through time as soi
Authors
J.J. Carrasco, J. C. Neff, J. W. Harden
The impact of boreal forest fire on climate warming
We report measurements and analysis of a boreal forest fire, integrating the effects of greenhouse gases, aerosols, black carbon deposition on snow and sea ice, and postfire changes in surface albedo. The net effect of all agents was to increase radiative forcing during the first year (34 ?? 31 Watts per square meter of burned area), but to decrease radiative forcing when averaged over an 80-year
Authors
J. T. Randerson, H. Liu, M.G. Flanner, S.D. Chambers, Y. Jin, P.G. Hess, G. Pfister, M.C. Mack, K.K. Treseder, L.R. Welp, F.S. Chapin, J. W. Harden, M. L. Goulden, E. Lyons, J. C. Neff, E.A.G. Schuur, C.S. Zender
Geomorphic control of landscape carbon accumulation
We use the CREEP process-response model to simulate soil organic carbon accumulation in an undisturbed prairie site in Iowa. Our primary objectives are to identify spatial patterns of carbon accumulation, and explore the effect of erosion on basin-scale C accumulation. Our results point to two general findings. First, redistribution of soil carbon by erosion results in a net increase in basin-wide
Authors
N.A. Rosenbloom, J. W. Harden, J. C. Neff, D. S. Schimel
Wildfires threaten mercury stocks in northern soils
With climate change rapidly affecting northern forests and wetlands, mercury reserves once protected in cold, wet soils are being exposed to burning, likely triggering large releases of mercury to the atmosphere. We quantify organic soil mercury stocks and burn areas across western, boreal Canada for use in fire emission models that explore controls of burn area, consumption severity, and fuel loa
Authors
M.R. Turetsky, J. W. Harden, H.R. Friedli, M. Flannigan, N. Payne, J. Crock, L. Radke
Effects of wildfire and permafrost on soil organic matter and soil climate in interior Alaska
The influence of discontinuous permafrost on ground-fuel storage, combustion losses, and postfire soil climates was examined after a wildfire near Delta Junction, AK in July 1999. At this site, we sampled soils from a four-way site comparison of burning (burned and unburned) and permafrost (permafrost and nonpermafrost). Soil organic layers (which comprise ground-fuel storage) were thicker in perm
Authors
J. W. Harden, K.L. Manies, M.R. Turetsky, J. C. Neff
Comparing electronic probes for volumetric water content of low-density feathermoss
Purpose - Feathermoss is ubiquitous in the boreal forest and across various land-cover types of the arctic and subarctic. A variety of affordable commercial sensors for soil moisture content measurement have recently become available and are in use in such regions, often in conjunction with fire-susceptibility or ecological studies. Few come supplied with calibrations suitable or suggested for soi
Authors
P.P. Overduin, K. Yoshikawa, D.L. Kane, J. W. Harden
Woody debris along an upland chronosequence in boreal Manitoba and its impact on long-term carbon storage
This study investigated the role of fire-killed woody debris as a source of soil carbon in black spruce (Picea mariana (Mill.) BSP) stands in Manitoba, Canada. We measured the amount of standing dead and downed woody debris along an upland chronosequence, including wood partially and completely covered by moss growth. Such woody debris is rarely included in measurement protocols and composed up to
Authors
K.L. Manies, J. W. Harden, B. P. Bond-Lamberty, K. P. O'Neill
Chemical weathering rates of a soil chronosequence on granitic alluvium: III. Hydrochemical evolution and contemporary solute fluxes and rates
Although long-term changes in solid-state compositions of soil chronosequences have been extensively investigated, this study presents the first detailed description of the concurrent hydrochemical evolution and contemporary weathering rates in such sequences. The most direct linkage between weathering and hydrology over 3 million years of soil development in the Merced chronosequence in Central C
Authors
A. F. White, M. S. Schulz, D.V. Vivit, A.E. Blum, David A. Stonestrom, J. W. Harden
Fire effects on soil organic matter content, composition, and nutrients in boreal interior Alaska
Boreal ecosystems contain a substantial fraction of the earth's soil carbon stores and are prone to frequent and severe wildfires. In this study, we examine changes in element and organic matter stocks due to a 1999 wildfire in Alaska. One year after the wildfire, burned soils contained between 1071 and 1420 g/m2 less carbon than unburned soils. Burned soils had lower nitrogen than unburned soils,
Authors
J. C. Neff, J. W. Harden, G. Gleixner
*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