Abstract
Devils Lake, Wisconsin (43°25.08′N, 89°43.92′W, 294 m asl) lies in a preglacial quartzite gorge, constrained by glacial deposits at the northern and southern ends. Presently, Devils Lake has a maximum water depth of ~12.5 m and surface area of 153 ha, but the lake and surrounding landscape underwent significant, complex changes during the last glacial maximum and the following deglacial period and Holocene.
The pollen stratigraphy obtained from a ~6m sediment core in the late 1970’s1 remains one of the most significant vegetation records from central North America. Devils Lake has been a key location for understanding long-term environmental changes across a grassland-forest transition zone. More recent AMS 14C dates2 have allowed a new age-depth model to be established which refines the basal age of the original sediment core to 15,158–14,190 cal yr BP, significantly altering the previously interpreted climatic conditions during the Younger Dryas chronozone. Because of its unusual formation, Devils Lake has the potential to provide information about very early post-glacial ecosystem development, as well as additional information about the biogeochemical changes coinciding with previously documented climate and vegetation changes.
We present here new geochemical and geophysical data from Devils Lake, WI that describe the evolution of ecosystems in the catchment. Analysis of stable nitrogen and carbon isotopes, high-resolution magnetic susceptibility, spectral analysis and scanning XRF has been performed on a new, ~10m long, sediment core. These new data offer insights into biogeochemical cycling over millennial timescales in the lake system and surrounding catchment, and the consequences of regional and local climatic conditions and environmental changes. Further, this record provides additional information on the local glacial dynamics (i.e. Green Bay Lobe) during the inception of the lake and initiation of sediment deposition.
The pollen stratigraphy obtained from a ~6m sediment core in the late 1970’s1 remains one of the most significant vegetation records from central North America. Devils Lake has been a key location for understanding long-term environmental changes across a grassland-forest transition zone. More recent AMS 14C dates2 have allowed a new age-depth model to be established which refines the basal age of the original sediment core to 15,158–14,190 cal yr BP, significantly altering the previously interpreted climatic conditions during the Younger Dryas chronozone. Because of its unusual formation, Devils Lake has the potential to provide information about very early post-glacial ecosystem development, as well as additional information about the biogeochemical changes coinciding with previously documented climate and vegetation changes.
We present here new geochemical and geophysical data from Devils Lake, WI that describe the evolution of ecosystems in the catchment. Analysis of stable nitrogen and carbon isotopes, high-resolution magnetic susceptibility, spectral analysis and scanning XRF has been performed on a new, ~10m long, sediment core. These new data offer insights into biogeochemical cycling over millennial timescales in the lake system and surrounding catchment, and the consequences of regional and local climatic conditions and environmental changes. Further, this record provides additional information on the local glacial dynamics (i.e. Green Bay Lobe) during the inception of the lake and initiation of sediment deposition.
| Original language | English |
|---|---|
| Publication status | Published - 24 Jun 2012 |
| Event | American Quaternary Association - Duluth, MN, United States of America Duration: 21 Jun 2012 → 24 Jun 2012 |
Conference
| Conference | American Quaternary Association |
|---|---|
| Country/Territory | United States of America |
| City | Duluth, MN |
| Period | 21 Jun 2012 → 24 Jun 2012 |
