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Cascading ecological effects of low-level phosphorus enrichment in the Florida Everglades Cascading ecological effects of low-level phosphorus enrichment in the Florida Everglades

Few studies have examined long-term ecological effects of sustained low-level nutrient enhancement on wetland biota. To determine sustained effects of phosphorus (P) addition on Everglades marshes we added P at low levels (5, 15, and 30 μg L−1 above ambient) for 5 yr to triplicate 100-m flow-through channels in pristine marsh. A cascade of ecological responses occurred in similar...
Authors
Evelyn Gaiser, Joel C. Trexler, Jennifer Richards, Daniel L. Childers, David Lee, A. L. Edwards, Leonard J. Scinto, Krish Jayachandran, Gregory E. Noe, Ronald D. Jones

Deciphering multiple Mesoproterozoic and Paleozoic events recorded in zircon and titanite from the Baltimore Gneiss, Maryland: SEM imaging, SHRIMP U-Pb geochronology, and EMP analysis Deciphering multiple Mesoproterozoic and Paleozoic events recorded in zircon and titanite from the Baltimore Gneiss, Maryland: SEM imaging, SHRIMP U-Pb geochronology, and EMP analysis

The Baltimore Gneiss, exposed in antiforms in the eastern Maryland Piedmont, consists of a suite of felsic and mafic gneisses of Mesoproterozoic age. Zircons from the felsic gneisses are complexly zoned, as shown in cathodoluminescence imaging; most zircon grains have multiple overgrowth zones, some of which are adjacent and parallel to elongate cores. Sensitive high-resolution ion...
Authors
John N. Aleinikoff, J. Wright Horton,, Avery A. Drake, R. P. Wintsch, C.M. Fanning, K. Yi

Ecosystem history of southern and central Biscayne Bay: Summary report on sediment core analyses - year two Ecosystem history of southern and central Biscayne Bay: Summary report on sediment core analyses - year two

The Comprehensive Everglades Restoration Plan (CERP) lists restoration of the timing, quantity, and quality of the natural flow of freshwater as one its primary goals. Before restoration can occur, however, the baseline conditions of the environment prior to significant human alteration must be established and the range of variation within the natural system must be determined. In...
Authors
G. Lynn Wingard, Thomas M. Cronin, Charles W. Holmes, Debra A. Willard, Gary S. Dwyer, Scott E. Ishman, William Orem, Christopher P. Williams, Jessica Albietz, Christopher E. Bernhardt, Carlos A. Budet, Bryan Landacre, Terry Lerch, Marci Marot, Ruth E. Ortiz

Bedrock geologic map of the New Milford quadrangle, Litchfield and Fairfield Counties, Connecticut Bedrock geologic map of the New Milford quadrangle, Litchfield and Fairfield Counties, Connecticut

The bedrock geology of the New Milford quadrangle, Litchfield and Fairfield Counties, Connecticut is described in this report. The database includes contacts of bedrock geologic units, faults, outcrops, structural geologic information, and photos.
Authors
Gregory J. Walsh

Atlas of pollen and spores of the Florida Everglades Atlas of pollen and spores of the Florida Everglades

An illustrated, descriptive atlas of pollen and spores from wetland plants of the Florida Everglades was compiled to facilitate identification of dispersed palynomorphs in sediments. The atlas includes 121 wetland species characteristic of eleven plant associations of the Florida Everglades including sloughs, sawgrass marshes, tree islands, wet prairies, cypress domes, mangrove forests...
Authors
Debra A. Willard, Christopher E. Bernhardt, Lisa M. Weimer, S. R. Cooper, Desire Gamez, Jennifer Jensen

U-Pb geochronology and evolution of Mesoproterozoic basement rocks, western Connecticut U-Pb geochronology and evolution of Mesoproterozoic basement rocks, western Connecticut

Geologic mapping and U-Pb geochronology by ion microprobe on zircon, titanite, and monazite in the New Milford quadrangle, western Connecticut indicate Meso-proterozoic events at ca. 1.3, 1.05, and 0.99 Ga in the Laurentian basement rocks. Pink granite gneiss (1311 ± 7 Ma) intruded a paragneiss sequence during the early stages of the Elzevirian orogeny. During the Ottawan orogeny, syn...
Authors
Gregory J. Walsh, John N. Aleinikoff, C. Mark Fanning

Coastal-change and glaciological map of the Saunders Coast area, Antarctica: 1972-97 Coastal-change and glaciological map of the Saunders Coast area, Antarctica: 1972-97

Satellite images from 1972 to 1997 have been used to prepare a map showing glaciological features of the Saunders Coast area, Antarctica. Analysis of the imagery shows a trend toward ice-front retreat that may be a result of changing environmental conditions.
Authors
Jane G. Ferrigno, Richard S. Williams, Kevin M. Foley

Digital engineering aspects of karst map:  A GIS version of Davies, W.E., Simpson, J.H., Ohlmacher, G.C., Kirk, W.S., and Newton, E.G., 1984, Engineering aspects of karst:  U.S. Geological Survey, National atlas of the United States of America, scale 1:7, Digital engineering aspects of karst map:  A GIS version of Davies, W.E., Simpson, J.H., Ohlmacher, G.C., Kirk, W.S., and Newton, E.G., 1984, Engineering aspects of karst:  U.S. Geological Survey, National atlas of the United States of America, scale 1:7,

These data are digital facsimiles of the original 1984 Engineering Aspects of Karst map by Davies and others. This data set was converted from a printed map to a digital GIS coverage to provide users with a citable national scale karst data set to use for graphic and demonstration purposes until new, improved data are developed. These data may be used freely with proper citation. Because...
Authors
Bret D. Tobin, David J. Weary

Origin of the Blue Ridge escarpment along the passive margin of Eastern North America Origin of the Blue Ridge escarpment along the passive margin of Eastern North America

The Blue Ridge escarpment is a rugged landform situated within the ancient Appalachian orogen. While similar in some respects to the great escarpments along other passive margins, which have evolved by erosion following rifting, its youthful topographic expression has inspired proposals of Cenozoic tectonic rejuvenation in eastern North America. To better understand the post-orogenic and...
Authors
J.A. Spotila, G.C. Bank, P.W. Reiners, C. W. Naeser, N. D. Naeser, B.S. Henika

Supergroup stratigraphy of the Atlantic and Gulf Coastal Plains (Middle? Jurassic through holocene, Eastern North America) Supergroup stratigraphy of the Atlantic and Gulf Coastal Plains (Middle? Jurassic through holocene, Eastern North America)

An inclusive supergroup stratigraphic framework for the Atlantic and Gulf Coastal Plains is proposed herein. This framework consists of five supergroups that 1) are regionally inclusive and regionally applicable, 2) meaningfully reflect the overall stratigraphic and structural history of the Coastal Plains geologic province of the southeastern United States, and 3) create stratigraphic...
Authors
Robert E. Weems, Jean Self-Trail, Lucy E. Edwards
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