Charles Umbanhowar Jr
Biographic Data
| ID | 5002152 |
|---|---|
| NAME | Charles Umbanhowar Jr |
| GIVEN NAMES | Charles |
| FAMILY NAME | Umbanhowar Jr |
| SIGNATURE | JR C U |
| AFFILIATIONS | St. Olaf College |
| ORCID | 0000-0002-1743-509X |
| VERIFIED | Yes |
| TOTAL WORKS | 11 |
| TOTAL CITATIONS | 46 |
| AUTHOR COUNT | 11 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 1963 |
| LATEST PUBLICATION YEAR | 2024 |
| H-INDEX | 3 |
Shallow lake response to Holocene climate variation in south-central Minnesota, USA
Sedimentary deposits in lakes across the upper Midwest record the co-evolution of climate and biogeochemistry since the retreat of the Laurentide Ice Sheet at the end of the last glacial period. Here, we report on a Holocene lake sediment record from Chub Lake, a shallow (3 m depth) eutrophic lake system in south-central Minnesota. High-resolution elemental data from scanning XRF along with variations in organic matter, carbonate minerals, clasti…
Landscape heterogeneity and response of lake ecosystems to changes in climate and peatland expansion over the past 7500 years at the tundra-forest border of northern Manitoba, Canada
Responses of Arctic lakes to climate change are complex and heterogeneous at regional to local scales, but there are few studies comparing multiple sites within the same landscape. We studied sediment cores recovered from seven lake sites located within the forest-tundra biome of northern Manitoba, Canada. We first used sediment core pollen from the seven sites to reconstruct July temperatures and total annual precipitation for the past 7500 year…
Improving the efficiency of sediment charcoal image analysis
Imaging of charcoal particles extracted from lake sediments provides an important way to understand past fire regimes. Imaging of large numbers of particles can be time consuming. In this note we explore the effects of subsampling and extrapolation of area on estimates of sum charcoal area, using resampling of real and simulated data sets and propose a protocol in which all particles are counted with only the first 100 encountered being imaged. E…
The effects of anthropogenic land cover change on pollen-vegetation relationships in the American Midwest
Late-Holocene moisture balance inferred from diatom and lake sediment records in western Mongolia
The Valley of the Great Lakes in western Mongolia is a unique ecosystem comprising a wide variety of terrestrial and aquatic habitats. Relatively little is known about the long-term climate history of the area or the relative impact of changes in climate and land use in the region. Tree-ring records have established an understanding of regional temperature fluctuations; however, the few records of moisture balance from Mongolia offer little insig…
Regional fire history based on charcoal analysis of sediments from nine lakes in western Mongolia
Fires are common in grassland regions of the world, and the frequency and severity of fire is linked to climate-driven changes in fuel loads. Western Mongolia is dominated by grasslands but the fire history of this region is largely unknown. We reconstructed modern fire (48 lakes) and historical fires (9 lakes) using sediment charcoal. Modern fuel loads were estimated using a combination of clipped plots, satellite-based estimates of annual above…
Asymmetric vegetation responses to mid-Holocene aridity at the prairie–forest ecotone in south-central Minnesota
The mid-Holocene (ca. 8000–4000 cal yr BP) was a time of marked aridity throughout much of Minnesota, and the changes due to mid-Holocene aridity are seen as an analog for future responses to global warming. In this study, we compare the transition into (ca. 9000–7000 yr ago) and out of (ca. 5000–2500 yr ago) the mid-Holocene (MH) period at Kimble Pond and Sharkey Lake, located along the prairie forest ecotone in south-central Minnesota, using hi…
Sediment-magnetic signature of land-use and drought as recorded in lake sediment from south-central Minnesota, USA
Sediment magnetic properties of a short core from Sharkey Lake, MN, record the effects of Euroamerican settlement and climate change over the last 150 yr. The onset of European-style farming led to increased erosion, reflected in high values of concentration-dependent parameters such as magnetic susceptibility ( ĸ ), Isothermal Remanent Magnetization (IRM), and Anhysteretic Remanent Magnetization (ARM). These high values are only partially due to…
Interaction of fire, climate and vegetation change at a large landscape scale in the Big Woods of Minnesota, USA
The Big Woods region of Minnesota is on the prairie-forest border and is a much studied model for the interaction of climate, fire and vegetation. The purpose of this study was (a) to document the extent and timing of changes in vegetation and fire over the past 2000 years and (b) to examine the link between charcoal influx and vegetation during the eighteenth and early nineteenth centuries. To reconstruct changes in vegetation, fire and climate,…
Experimental production and analysis of microscopic charcoal from wood, leaves and grasses
Study of microscopic charcoal from lake sediments has led to a greater understanding of past veg etation, climate and fire ecology. We investigated the potential of charcoal morphology as an indicator of vegetation type. Grasses, leaves and wood were burned under controlled conditions in the laboratory, and we used a dissecting scope, video camera, and image-capture software to image-sieved (125-μm screen) micro-scopic charcoal. Charcoal from gra…
Marshall on Judging
Marshall on Judging Get access Charles Edward Umbanhowar Charles Edward Umbanhowar Graduate student *Department of Political Science, University of Chicago Search for other works by this author on: Oxford Academic Google Scholar American Journal of Legal History, Volume 7, Issue 3, July 1963, Pages 210–227, https://doi.org/10.2307/844424 Published: 01 July 1963
Experimental production and analysis of microscopic charcoal from wood, leaves and grasses
Study of microscopic charcoal from lake sediments has led to a greater understanding of past veg etation, climate and fire ecology. We investigated the potential of charcoal morphology as an indicator of vegetation type. Grasses, leaves and wood were burned under controlled conditions in the laboratory, and we used a dissecting scope, video camera, and image-capture software to image-sieved (125-μm screen) micro-scopic charcoal. Charcoal from gra…
Regional fire history based on charcoal analysis of sediments from nine lakes in western Mongolia
Fires are common in grassland regions of the world, and the frequency and severity of fire is linked to climate-driven changes in fuel loads. Western Mongolia is dominated by grasslands but the fire history of this region is largely unknown. We reconstructed modern fire (48 lakes) and historical fires (9 lakes) using sediment charcoal. Modern fuel loads were estimated using a combination of clipped plots, satellite-based estimates of annual above…
Interaction of fire, climate and vegetation change at a large landscape scale in the Big Woods of Minnesota, USA
The Big Woods region of Minnesota is on the prairie-forest border and is a much studied model for the interaction of climate, fire and vegetation. The purpose of this study was (a) to document the extent and timing of changes in vegetation and fire over the past 2000 years and (b) to examine the link between charcoal influx and vegetation during the eighteenth and early nineteenth centuries. To reconstruct changes in vegetation, fire and climate,…
The effects of anthropogenic land cover change on pollen-vegetation relationships in the American Midwest
Late-Holocene moisture balance inferred from diatom and lake sediment records in western Mongolia
The Valley of the Great Lakes in western Mongolia is a unique ecosystem comprising a wide variety of terrestrial and aquatic habitats. Relatively little is known about the long-term climate history of the area or the relative impact of changes in climate and land use in the region. Tree-ring records have established an understanding of regional temperature fluctuations; however, the few records of moisture balance from Mongolia offer little insig…
Marshall on Judging
Marshall on Judging Get access Charles Edward Umbanhowar Charles Edward Umbanhowar Graduate student *Department of Political Science, University of Chicago Search for other works by this author on: Oxford Academic Google Scholar American Journal of Legal History, Volume 7, Issue 3, July 1963, Pages 210–227, https://doi.org/10.2307/844424 Published: 01 July 1963
Experimental production and analysis of microscopic charcoal from wood, leaves and grasses
Study of microscopic charcoal from lake sediments has led to a greater understanding of past veg etation, climate and fire ecology. We investigated the potential of charcoal morphology as an indicator of vegetation type. Grasses, leaves and wood were burned under controlled conditions in the laboratory, and we used a dissecting scope, video camera, and image-capture software to image-sieved (125-μm screen) micro-scopic charcoal. Charcoal from gra…
Sediment-magnetic signature of land-use and drought as recorded in lake sediment from south-central Minnesota, USA
Sediment magnetic properties of a short core from Sharkey Lake, MN, record the effects of Euroamerican settlement and climate change over the last 150 yr. The onset of European-style farming led to increased erosion, reflected in high values of concentration-dependent parameters such as magnetic susceptibility ( ĸ ), Isothermal Remanent Magnetization (IRM), and Anhysteretic Remanent Magnetization (ARM). These high values are only partially due to…
Interaction of fire, climate and vegetation change at a large landscape scale in the Big Woods of Minnesota, USA
The Big Woods region of Minnesota is on the prairie-forest border and is a much studied model for the interaction of climate, fire and vegetation. The purpose of this study was (a) to document the extent and timing of changes in vegetation and fire over the past 2000 years and (b) to examine the link between charcoal influx and vegetation during the eighteenth and early nineteenth centuries. To reconstruct changes in vegetation, fire and climate,…
Asymmetric vegetation responses to mid-Holocene aridity at the prairie–forest ecotone in south-central Minnesota
The mid-Holocene (ca. 8000–4000 cal yr BP) was a time of marked aridity throughout much of Minnesota, and the changes due to mid-Holocene aridity are seen as an analog for future responses to global warming. In this study, we compare the transition into (ca. 9000–7000 yr ago) and out of (ca. 5000–2500 yr ago) the mid-Holocene (MH) period at Kimble Pond and Sharkey Lake, located along the prairie forest ecotone in south-central Minnesota, using hi…
Regional fire history based on charcoal analysis of sediments from nine lakes in western Mongolia
Fires are common in grassland regions of the world, and the frequency and severity of fire is linked to climate-driven changes in fuel loads. Western Mongolia is dominated by grasslands but the fire history of this region is largely unknown. We reconstructed modern fire (48 lakes) and historical fires (9 lakes) using sediment charcoal. Modern fuel loads were estimated using a combination of clipped plots, satellite-based estimates of annual above…
Late-Holocene moisture balance inferred from diatom and lake sediment records in western Mongolia
The Valley of the Great Lakes in western Mongolia is a unique ecosystem comprising a wide variety of terrestrial and aquatic habitats. Relatively little is known about the long-term climate history of the area or the relative impact of changes in climate and land use in the region. Tree-ring records have established an understanding of regional temperature fluctuations; however, the few records of moisture balance from Mongolia offer little insig…
The effects of anthropogenic land cover change on pollen-vegetation relationships in the American Midwest
Improving the efficiency of sediment charcoal image analysis
Imaging of charcoal particles extracted from lake sediments provides an important way to understand past fire regimes. Imaging of large numbers of particles can be time consuming. In this note we explore the effects of subsampling and extrapolation of area on estimates of sum charcoal area, using resampling of real and simulated data sets and propose a protocol in which all particles are counted with only the first 100 encountered being imaged. E…
Shallow lake response to Holocene climate variation in south-central Minnesota, USA
Sedimentary deposits in lakes across the upper Midwest record the co-evolution of climate and biogeochemistry since the retreat of the Laurentide Ice Sheet at the end of the last glacial period. Here, we report on a Holocene lake sediment record from Chub Lake, a shallow (3 m depth) eutrophic lake system in south-central Minnesota. High-resolution elemental data from scanning XRF along with variations in organic matter, carbonate minerals, clasti…
Landscape heterogeneity and response of lake ecosystems to changes in climate and peatland expansion over the past 7500 years at the tundra-forest border of northern Manitoba, Canada
Responses of Arctic lakes to climate change are complex and heterogeneous at regional to local scales, but there are few studies comparing multiple sites within the same landscape. We studied sediment cores recovered from seven lake sites located within the forest-tundra biome of northern Manitoba, Canada. We first used sediment core pollen from the seven sites to reconstruct July temperatures and total annual precipitation for the past 7500 year…
Geology and Paleoclimatology Research (9 works) · Environmental Science (8 works) · Geography (7 works) · Physical geography (7 works) · Charcoal (5 works) · Climate change (5 works) · Ecology (5 works) · Geology (5 works) · Ecosystem (4 works) · Fire effects on ecosystems (4 works)