How Natural is Nature? The Effect of Burning on Presettlement Vegetation in West-Central Illinois

When the first Euroamericans arrived in North America, they thought they were seeing a “wilderness,” unaltered by human hands. However, they were actually seeing highly managed environments. Kilburn and Brugam examine the impact of the burning of forests and prairies by Native Americans on the plant species in west-central Illinois

Survival of Fishes in a Stormwater Retention Pond at the Watershed Nature Center, Edwardsville, Illinois

A study of the Upper Pond at the Edwardsville Watershed Nature Center (WNC) was conducted to discover the potential cause of fish kills in the small stormwater retention pond and to determine how the current populations of bluegill (Lepomis macrochirus), redear sunfish (Lepomis microlophus), common carp (Cyprinus carpio) and largemouth bass (Micropterus salmoides) can survive in the pond based on prevailing environmental conditions. Dissolved oxygen (DO) was measured from June 19 to December 5, 2019 at a site in the center of the open lake (4 m deep) and from a dock near the shore (1.1 m deep). Water temperature was measured intermittently at both sites from June 19 to November 4. In the open lake, oxygen levels reached a peak of 11.6 mg/L at the surface on July 2. Below 2.5 m DO remained less than 1.5 mg/L until Oct. 8 when it slowly began to rise reaching a high of 10.8 on Nov. 20. The dock station had similar oxygen levels. Temperature varied from a high of 31.2 °C on July 21 to a low of 6.5° C on November 3. The low DO in the pond results from a nearly continuous cover of duckweed (Lemna sps) which prevents interchange of oxygen with the atmosphere. It is likely that the low oxygen levels select for fish species that are physiologically and behaviorally capable of surviving hypoxia

Post-mining neutralization of acidic surface mine lakes

Twenty core samples and 54 surface sediment samples were taken from surface mine lakes in Missouri, Illinois, and Indiana to determine the rates of neutralization of acid mine lakes. Sediment samples were analyzed for diatom microfossils, selected chemical elements, and the radionuclide, lead-210. The surface samples showed that there were strong differences in diatom microfossils between acidic and neutral lakes but there was no strong difference in sediment chemical composition between acidic and neutral lakes. Of 20 lakes from which cores were examined, 9 showed diatom evidence of neutralization and one of acidification over time. Cores from 5 of these were dated using lead-210 analysis. Diatom microfossils showed that neutralization took from less than 3 years to 30 years to occur. Comparisons between lake sediment and water column chemistry indicated that neither sulfide deposition nor H2S outgasing is likely to play a major role in the neutralization process. Chemical analyses of lake sediment showed that the sediment is a sink for heavy metals. These metals are held as sulfides. There is also a considerable fraction of metal ions strongly bound to clays. This research demonstrates that acid lake neutralization is common, that it occurs over moderate time spans and that the rate is controlled by rates of acid supply from the watershed.U.S. Department of the InteriorU.S. Geological SurveyOpe

The impact of nitrogen contamination and river modification on a Mississippi River floodplain lake

Anthropogenic nitrogen contamination has increased in ecosystems around the world (frequently termed the “nitrogen cascade”). Coke production for steel manufacturing is often overlooked as a source of nitrogen to natural ecosystems. We examined sediment cores from a Horseshoe Lake, a floodplain lake located just East of St. Louis Missouri (USA) to test whether a coking plant effluent could be traced using stable isotopes of nitrogen and diatom microfossils. The distribution of δ15N values in surface sediment samples from the lake shows the highest values near the coking plant effluent. Analysis stable isotopes of nitrogen from sediment cores using a binary mixing model showed three sources of nitrogen since 1688 CE. The first source (active between 1688 and 1920 CE) had a calculated δ15N value of -.8±.4‰. After 1920 a second source with a δ15N of 20.2±2.0 ‰ became active. The diatom microfossil assemblages present from 1688 CE to the late 1800’s are dominated by the planktonic species Aulacoseira granulata and periphytic and benthic genera Gomphonema, Cocconeis, and Lyrella. After the late 1800’s the diatom assemblages are dominated by Staurosira species indicating a shift of species from high flow riverine environments to epipelic species from a lake environment. Our results show how stable isotopes of nitrogen can be used to track nitrogen inputs from industrial sources. They suggest that the high nitrogen input has not been a major source of eutrophication in the lake

Pre-settlement Vegetation of Greene, Jersey and Macoupin Counties along the Prairie/Forest Border in Illinois

The US Federal Government established the Public Land Survey (PLS) to survey federal land before sale to settlers in the early 1800’s. We used a Geographic Information System (GIS) and the PLS to explore the relationship among forests, fire frequency, topography, and soils in Greene, Jersey and Macoupin Counties in Illinois. The PLS data was digitized from microfiche copies of the survey in the Lovejoy Library at Southern Illinois University Edwardsville. The floodplains along the Illinois River supported a fire-intolerant forest of Salix sp., Populus deltoides, Acer spp., and Fraxinus spp. The floodplain is bordered by a line of bluffs which forms a region of broken topography supporting moderately fire tolerant species on alfisols. To the East is a region of mixed prairie and forest. The prairie was on flat mollisols where it was intermixed with the forest on and hillier slopes and alfisols. The forest areas supported highly fire tolerant forest trees with large diameters at large distances from survey points. Non-Metric Multidimensional scaling reveals a close relationship among topography, vegetation and soils. Forests were on hilly land. Prairies were located on level uplands where there were no firebreaks. Floodplains are just as level as prairies. They are also located on mollisols adjacent to the river. They are protected from fire by sloughs, swamps and lakes. The results of our study support the conclusion that topography and moisture is an important control on the geographical distribution of vegetation in the study area. These factors likely operated by controlling fire frequency

Pre-settlement Vegetation of Greene, Jersey and Macoupin Counties along the Prairie/Forest Border in Illinois

The US Federal Government established the Public Land Survey (PLS) to survey federal land before sale to settlers in the early 1800’s. We used a Geographic Information System (GIS) and the PLS to explore the relationship among forests, fire frequency, topography, and soils in Greene, Jersey and Macoupin Counties in Illinois. The PLS data was digitized from microfiche copies of the survey in the Lovejoy Library at Southern Illinois University Edwardsville. The floodplains along the Illinois River supported a fire-intolerant forest of Salix sp., Populus deltoides, Acer spp., and Fraxinus spp. The floodplain is bordered by a line of bluffs which forms a region of broken topography supporting moderately fire tolerant species on alfisols. To the East is a region of mixed prairie and forest. The prairie was on flat mollisols where it was intermixed with the forest on and hillier slopes and alfisols. The forest areas supported highly fire tolerant forest trees with large diameters at large distances from survey points. Non-Metric Multidimensional scaling reveals a close relationship among topography, vegetation and soils. Forests were on hilly land. Prairies were located on level uplands where there were no firebreaks. Floodplains are just as level as prairies. They are also located on mollisols adjacent to the river. They are protected from fire by sloughs, swamps and lakes. The results of our study support the conclusion that topography and moisture is an important control on the geographical distribution of vegetation in the study area. These factors likely operated by controlling fire frequency

Sedimentary evidence of hurricane strikes in western Long Island, New York

Author Posting. © American Geophysical Union, 2007. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry Geophysics Geosystems 8 (2007): Q06011, doi:10.1029/2006GC001463.Evidence of historical landfalling hurricanes and prehistoric storms has been recovered from backbarrier environments in the New York City area. Overwash deposits correlate with landfalls of the most intense documented hurricanes in the area, including the hurricanes of 1893, 1821, 1788, and 1693 A.D. There is little evidence of intense hurricane landfalls in the region for several hundred years prior to the late 17th century A.D. The apparent increase in intense hurricane landfalls around 300 years ago occurs during the latter half of the Little Ice Age, a time of lower tropical sea surface temperatures. Multiple washovers laid down between ~2200 and 900 cal yr B.P. suggest an interval of frequent intense hurricane landfalls in the region. Our results provide preliminary evidence that fluctuations in intense hurricane landfall in the northeastern United States were roughly synchronous with hurricane landfall fluctuations observed for the Caribbean and Gulf Coast, suggesting North Atlantic–wide changes in hurricane activity.Grants from the National Science Foundation (EAR 0519118), Risk Prediction Initiative at the Bermuda Biological Station for Research, and the Coastal Ocean Institute of Woods Hole Oceanographic Institution supported this research

Ancient DNA from lake sediments: Bridging the gap between paleoecology and genetics

<p>Abstract</p> <p>Background</p> <p>Quaternary plant ecology in much of the world has historically relied on morphological identification of macro- and microfossils from sediments of small freshwater lakes. Here, we report new protocols that reliably yield DNA sequence data from Holocene plant macrofossils and bulk lake sediment used to infer ecological change. This will allow changes in census populations, estimated from fossils and associated sediment, to be directly associated with population genetic changes.</p> <p>Results</p> <p>We successfully sequenced DNA from 64 samples (out of 126) comprised of bulk sediment and seeds, leaf fragments, budscales, and samaras extracted from Holocene lake sediments in the western Great Lakes region of North America. Overall, DNA yields were low. However, we were able to reliably amplify samples with as few as 10 copies of a short cpDNA fragment with little detectable PCR inhibition. Our success rate was highest for sediments < 2000 years old, but we were able to successfully amplify DNA from samples up to 4600 years old. DNA sequences matched the taxonomic identity of the macrofossil from which they were extracted 79% of the time. Exceptions suggest that DNA molecules from surrounding nearby sediments may permeate or adhere to macrofossils in sediments.</p> <p>Conclusions</p> <p>An ability to extract ancient DNA from Holocene sediments potentially allows exciting new insights into the genetic consequences of long-term environmental change. The low DNA copy numbers we found in fossil material and the discovery of multiple sequence variants from single macrofossil extractions highlight the need for careful experimental and laboratory protocols. Further application of these protocols should lead to better understanding of the ecological and evolutionary consequences of environmental change.</p