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Publications

Publications from USGS science centers throughout the Southeast Region.

Filter Total Items: 10379

Community involvement in a multimedia outreach project for Caddo Lake, Texas Community involvement in a multimedia outreach project for Caddo Lake, Texas

Caddo Lake is located in northeast Texas and northwest Louisiana and is the largest freshwater lake in Texas. A portion of the lake in Texas has been designated a "Wetland of International Significance" under the Ramsar Convention of the United Nations. The human community in the watershed has experienced a number of hydrological alterations to Caddo Lake over the last 100 years by the...
Authors
Scott A. Wilson, Carroll L. Cordes

Assessment of acreage and vegetation change in Florida's Big Bend tidal wetlands using satellite imagery Assessment of acreage and vegetation change in Florida's Big Bend tidal wetlands using satellite imagery

Fluctuations in sea level and impending development on the west coast of Florida have aroused concern for the relatively pristine tidal marshes of the Big Bend. Landsat Thematic Mapper (TM) images for 1986 and 1995 are processed and evaluated for signs of change. The images cover 250 km of Florida's Big Bend Gulf Coast, encompassing 160,000 acres of tidal marshes. Change is detected...
Authors
Ellen A. Raabe, Richard P. Stumpf

Comparison of the 2-, 25-, and 100-year recurrence interval floods computed from observed data with the 1995 urban flood-frequency estimating equations for Georgia Comparison of the 2-, 25-, and 100-year recurrence interval floods computed from observed data with the 1995 urban flood-frequency estimating equations for Georgia

Flood-frequency relations were computed for 28 urban stations, for 2-, 25-, and 100-year recurrence interval floods and the computations were compared to corresponding recurrence interval floods computed from the estimating equations from a 1995 investigation. Two stations were excluded from further comparisons or analyses because neither station had a significant flood during the period...
Authors
Ernest J. Inman

Agricultural chemicals in groundwater of the midwestern United States: Relations to land use Agricultural chemicals in groundwater of the midwestern United States: Relations to land use

To determine the relations between land use and concentrations of selected agricultural chemicals (nitrate, atrazine residue [atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) + deethylatrazinc (2-amino-4-chloro-6-isopropylamino-s-triazine) + deisopropylatrazine (2-amino-4-chloro-6-ethylamino-s-triazine)], and alachlor residue [alachlor, [2-chloro-2′,6′-diethyl-N-...
Authors
D.W. Kolpin

Evaluation of a mallard HSI model for the Lower Mississippi Valley Evaluation of a mallard HSI model for the Lower Mississippi Valley

We evaluated a habitat suitability (HSI) model developed for mallards (Anas platyrhynchos) wintering in the Lower Mississippi Valley by comparing mallard densities obtained from aerial surveys with habitat suitability indices derived from satellite imagery for 25, 256km2 sampling units. Regression models that related mallard densities to habitat suitability indices accounted for only 29%...
Authors
D.J. Twedt, Michael W. Brown, James R. Nassar

Population viability analysis of the Florida manatee (Trichechus manatus latirostris), 1976-1991 Population viability analysis of the Florida manatee (Trichechus manatus latirostris), 1976-1991

Recent development of age-determination techniques for Florida manatees (Trichechus manatus latirostris) has permitted derivation of age-specific data on reproduction and survival of a sample of 1212 carcasses obtained throughout Florida from 1976–1991. Population viability analysis using these data projects a slightly negative growth rate (−0.003) and an unacceptably low probability of
Authors
M. Marmontel, S.R. Humphrey, T. J. O'Shea

Temporal trends of selected agricultural chemicals in Iowa's groundwater, 1982-1995: Are things getting better? Temporal trends of selected agricultural chemicals in Iowa's groundwater, 1982-1995: Are things getting better?

Since 1982, the Iowa Groundwater Monitoring (IGWM) Program has been used to sample untreated groundwater from Iowa municipal wells for selected agricultural chemicals. This long-term database was used to determine if concentrations of select agricultural chemicals in groundwater have changed with time. Nitrate, alachlor [2-chloro-2′-6′-diethyl-N-(methoxymethyl)-acetanilide], atrazine (2...
Authors
D.W. Kolpin, D. Sneck-Fahrer, G.R. Hallberg, R.D. Libra
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