Conference Papers
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Browse almost 5,000 conference papers authored by our scientists and refine search by topic, location, year, and advanced search.
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Landsat multispectral sharpening using a sensor system model and panchromatic image Landsat multispectral sharpening using a sensor system model and panchromatic image
The thematic mapper (TM) sensor aboard Landsats 4, 5 and enhanced TM plus (ETM+) on Landsat 7 collect imagery at 30-m sample distance in six spectral bands. New with ETM+ is a 15-m panchromatic (P) band. With image sharpening techniques, this higher resolution P data, or as an alternative, the 10-m (or 5-m) P data of the SPOT satellite, can increase the spatial resolution of the...
Authors
G.P. Lemeshewsky
Lessons from the fires of 2000: Post-fire heterogeneity in ponderosa pine forests Lessons from the fires of 2000: Post-fire heterogeneity in ponderosa pine forests
We evaluate burn-severity patterns for six burns that occurred in the southern Rocky Mountains and the Colorado Plateau in 2000. We compare the results of two data sources: Burned Area Rehabilitations Teams (BAER) and a spatial burnseverity model derived from satellite imagery (the Normalized Burn Ratio; NBR). BAER maps tended to overestimate area of severe burns and underestimate area...
Authors
Natasha B. Kotliar, Sandra L. Haire, Carl H. Key
Linking Proxy-Based and Datum-Based Shorelines on a High-Energy Coastline: Implications for Shoreline Change Analyses Linking Proxy-Based and Datum-Based Shorelines on a High-Energy Coastline: Implications for Shoreline Change Analyses
A primary purpose of this paper is to quantitatively link variously defined and derived shoreline estimates commonly used for shoreline change analysis. Estimates of shoreline mapping and derivation error, natural shoreline variability, and the relationships between horizontally-derived (proxy-based) shorelines to vertical datums (e.g. MHW) are presented. A series of shoreline...
Authors
P. Ruggiero, G. M. Kaminsky, G. Gelfenbaum
Local extinction and turnover rates at the edge and interior of species' ranges Local extinction and turnover rates at the edge and interior of species' ranges
One hypothesis for the maintenance of the edge of a species' range suggests that more central (and abundant) populations are relatively stable and edge populations are less stable with increased local extinction and turnover rates. To date, estimates of such metrics are equivocal due to design and analysis flaws. Apparent increased estimates of extinction and turnover rates at the edge...
Authors
P.F. Doherty, T. Boulinier, D. Nichols James.
Low-head sea lamprey barrier effects on stream habitat and fish communities in the Great Lakes basin Low-head sea lamprey barrier effects on stream habitat and fish communities in the Great Lakes basin
Low-head barriers are used to block adult sea lamprey (Petromyzon marinus) from upstream spawning habitat. However, these barriers may impact stream fish communities through restriction of fish movement and habitat alteration. During the summer of 1996, the fish community and habitat conditions in twenty-four stream pairs were sampled across the Great Lakes basin. Seven of these stream...
Authors
H.R. Dodd, D.B. Hayes, J.R. Baylis, L.M. Carl, J.D. Goldstein, R. L. McLaughlin, D.L.G. Noakes, L.M. Porto, M.L. Jones
Mapping Shoreline Change Using Digital Orthophotogrammetry on Maui, Hawaii Mapping Shoreline Change Using Digital Orthophotogrammetry on Maui, Hawaii
Digital, aerial orthophotomosaics with 0.5-3.0 m horizontal accuracy, used with NOAA topographic maps (T-sheets), document past shoreline positions on Maui Island, Hawaii. Outliers in the shoreline position database are determined using a least median of squares regression. Least squares linear regression of the reweighted data (outliers excluded) is used to determine a shoreline trend...
Authors
C. Fletcher, J. Rooney, M. Barbee, S.-C. Lim, B. Richmond
Mercury and methylmercury contents in mine-waste calcine, water, and sediment collected from the Palawan Quicksilver mine, Philippines Mercury and methylmercury contents in mine-waste calcine, water, and sediment collected from the Palawan Quicksilver mine, Philippines
The Palawan Quicksilver mine, Philippines, produced about 2,900 t of mercury during mining of cinnabar ore from 1953 to 1976. More than 2,000,000 t of mine-waste calcines (retorted ore) were produced during mining, much of which were used to construct a jetty in nearby Honda Bay. Since 1995, high Hg contents have been found in several people living near the mine, and 21 of these people...
Authors
J. E. Gray, I.A. Greaves, D.M. Bustos, D. P. Krabbenhoft
Mercury contamination chronologies from Connecticut wetlands and Long Island Sound sediments Mercury contamination chronologies from Connecticut wetlands and Long Island Sound sediments
Sediment cores were used to investigate the mercury deposition histories of Connecticut and Long Island Sound. Most cores show background (pre-1800s) concentrations (50–100 ppb Hg) below 30–50 cm depth, strong enrichments up to 500 ppb Hg in the core tops with lower Hg concentrations in the surface sediments (200–300 ppb Hg). A sediment core from the Housatonic River has peak levels of 1...
Authors
J.C. Varekamp, B. Kreulen, Marilyn R. Buchholtz ten Brink, E.L. Mecray
Mercury in US coal: Observations using the COALQUAL and ICR data Mercury in US coal: Observations using the COALQUAL and ICR data
The COALQUAL data set lists the mercury content of samples collected from the in-ground US coal resource, whereas the ICR data set lists the mercury content of samples collected from coal shipments delivered to US electric utilities. After selection and adjustment of records, the COALQUAL data average 0.17 ??g Hg/g dry coal or 5.8 kg Hg/PJ, whereas the ICR data average 0.10 ??g Hg/g dry...
Authors
J.C. Quick, T.C. Brill, D.E. Tabet
Mercury methylation in mine wastes collected from abandoned mercury mines in the USA Mercury methylation in mine wastes collected from abandoned mercury mines in the USA
Speciation and transformation of Hg was studied in mine wastes collected from abandoned Hg mines at McDermitt, Nevada, and Terlingua, Texas, to evaluate formation of methyl-Hg, which is highly toxic. In these mine wastes, we measured total Hg and methyl-Hg contents, identified various Hg compounds using a pyrolysis technique, and determined rates of Hg methylation and methyl-Hg...
Authors
J. E. Gray, M.E. Hines, H. Biester, B.K. Lasorsa
Metals, trace elements, and organochlorine compounds in bottom sediment of Tuttle Creek Lake, Kansas, U.S.A. Metals, trace elements, and organochlorine compounds in bottom sediment of Tuttle Creek Lake, Kansas, U.S.A.
Bottom-sediment cores were used to investigate the occurrence of 44 metals and trace elements, and 15 organochlorine compounds in Tuttle Creek Lake, a reservoir with an agricultural basin in northeast Kansas, U.S.A. On the basis of U.S. Environmental Protection Agency sediment-quality guidelines, concentrations of Ag, As, Cr, Cu, Ni, and Zn frequently or typically exceeded the threshold...
Authors
K. E. Juracek, D.P. Mau
Modeling manatee response to restoration in the Everglades and Ten Thousand Islands Modeling manatee response to restoration in the Everglades and Ten Thousand Islands
No abstract available.
Authors
Bradley Stith, James P. Reid, Dean E. Easton, Susan M. Butler