Accurate mass analysis of ethanesulfonic acid degradates of acetochlor and alachlor using high-performance liquid chromatography and time-of-flight mass spectrometry
E.M. Thurman, I. Ferrer, R. Parry
2002, Conference Paper, Journal of Chromatography A
Degradates of acetochlor and alachlor (ethanesulfonic acids, ESAs) were analyzed in both standards and in a groundwater sample using high-performance liquid chromatography-time-of-flight mass spectrometry with electrospray ionization. The negative pseudomolecular ion of the secondary amide of acetochlor ESA and alachlor ESA gave average masses of 256.0750??0.0049 amu and 270.0786??0.0064 amu...
Components of productivity in black-legged kittiwakes Rissa tridactyla: Response to supplemental feeding
V.A. Gill, Scott A. Hatch
2002, Journal of Avian Biology (33) 113-126
In contrast to the high productivity of black‐legged kittiwakes in Britain, kittiwakes at many colonies in Alaska have failed chronically to reproduce since the mid 1970s. To determine if food is limiting productivity and, if so, at what stages of nesting food shortages are most severe, in 1996 and 1997...
Hydrographic and particle distributions over the Palos Verdes continental shelf: Spatial, seasonal and daily variability
B.H. Jones, M.A. Noble, T.D. Dickey
2002, Continental Shelf Research (22) 945-965
Moorings and towyo mapping were used to study the temporal and spatial variability of physical processes and suspended particulate material over the continental shelf of the Palos Verdes Peninsula in southwestern Los Angeles, California during the late summer of 1992 and winter of 1992-93. Seasonal evolution of the hydrographic structure...
Land use and flow regime effects on phosphorus chemical dynamics in the fluvial sediment of the Winooski River, Vermont
R.W. McDowell, A.N. Sharpley, A.T. Chalmers
2002, Ecological Engineering (18) 477-487
In the last century, fourfold increase in phosphorus (P) loadings to Lake Champlain, Vermont (VT), USA, have led to nuisance levels of algal growth occurring more often. To better understand the transport, storage, and cycling of P within the lake's catchment, we examined the chemistry, bioavailability and processes controlling sediment...
Source of solutes to the coastal sabkha of Abu Dhabi
W.W. Wood, W. E. Sanford, A.R.S. Al Habshi
2002, Geological Society of America Bulletin (114) 259-268
An ascending-brine model is proposed to address the observed isotope geochemistry, solute composition, and solute and water fluxes in the coastal sabkha of the Emirate of Abu Dhabi. Mass-balance measurements document that >95% of the solutes are derived from ascending continental brines; minor amounts are derived from rainfall and from...
Multiple-bench architecture and interpretations of original mire phases - Examples from the Middle Pennyslvanian of the Central Appalachian Basin, USA
S.F. Greb, C.F. Eble, J.C. Hower, W.M. Andrews
2002, International Journal of Coal Geology (49) 147-175
Coal seams often exhibit lateral and vertical variability in composition. When sampled as a whole seam this variability is masked. But if a seam is subdivided into correlateable components, this variability can be tested and better understood. Herein, an architectural approach is used to divide seams into intra-seam components. Clastic...
The National Vegetation Classification Standard applied to the remote sensing classification of two semiarid environments
Elijah W. Ramsey III, G.A. Nelson, D. Echols, S.K. Sapkota
2002, Environmental Management (29) 703-715
The National Vegetation Classification Standard (NVCS) was implemented at two US National Park Service (NPS) sites in Texas, the Padre Island National Seashore (PINS) and the Lake Meredith National Recreation Area (LM-NRA), to provide information for NPS oil and gas management plans. Because NVCS landcover classifications did not exist for...
Salt deposits in Arizona promise gas-storage opportunities
S.L. Rauzi
2002, Oil & Gas Journal (100) 68-70
Massive salt formations and their proximity to pipeline systems and power plants make Arizona attractive for natural gas storage. Caverns dissolved in subsurface salt are used to store LPG at Ferrellgas Partners LP facility near Holbrook and the AmeriGas Partners LP facility near Glendale. Three other companies are investigating the...
Organochlorine chemical residues in fish from the Mississippi River basin, 1995
C. J. Schmitt
2002, Archives of Environmental Contamination and Toxicology (43) 81-97
Fish were collected in late 1995 from 34 National Contaminant Biomonitoring Program (NCBP) stations and 13 National Water Quality Assessment Program (NAWQA) stations in the Mississippi River basin (MRB) and in late 1996 from a reference site in West Virginia. Four composite samples, each comprising (nominally) 10 adult common carp...
Comparison of the Eastern and Western Kentucky coal fields (Pennsylvanian), USA-why are coal distribution patterns and sulfur contents so different in these coal fields?
S.F. Greb, C.F. Eble, D.R. Chesnut Jr.
2002, International Journal of Coal Geology (50) 89-118
More than 130 Mt of Pennsylvanian coal is produced annually from two coal fields in Kentucky. The Western Kentucky Coal Field occurs in part of the Illinois Basin, an intercratonic basin, and the Eastern Kentucky Coal Field occurs in the Central Appalachian Basin, a foreland basin. The basins are only...
Differential use of a Wolf, Canis lupus, pack territory edge and core
L.D. Mech, E. K. Harper
2002, Canadian Field-Naturalist (116) 315-316
Based on 418 radio-locations of a Minnesota Wolf pack, Wolves were found at significantly fewer locations per area in the outer 2 km of the territory than in the core. This finding supports an hypothesis that buffer zones exist between pack territories and may explain why prey survive longer there....
Prioritizing conservation potential of arid-land montane natural springs and associated riparian areas
B.C. Thompson, P. L. Matusik-Rowan, K.G. Boykin
2002, Journal of Arid Environments (50) 527-547
Using inventory data and input from natural resource professionals, we developed a classification system that categorizes conservation potential for montane natural springs. This system contains 18 classes based on the presence of a riparian patch, wetland species, surface water, and evidence of human activity. We measured physical and biological components...
A source-depth separation filter: Using the Euler method on the derivatives of total intensity magnetic anomaly data
D. Ravat, K. Kirkham, T.G. Hildenbrand
2002, Leading Edge (Tulsa, OK) (21) 360-365
Derivatives of potential-field anomalies (or the anomaly gradients) enhance the field associated with shallow features and de-emphasize the field from deeper sources. The derivative approach of separating anomalies of shallow, intermediate, and deep sourves is, however, qualitative.Semiautomatic source...
A landscape ecology approach to assessing development impacts in the tropics: A geothermal energy example in Hawaii
J. A. Griffith, C.C. Trettin, R. V. O’Neill
2002, Singapore Journal of Tropical Geography (23) 1-22
Geographic information systems (GIS) are increasingly being used in environmental impact assessments (EIA) because GIS is useful for analysing spatial impacts of various development scenarios. Spatially representing these impacts provides another tool for landscape ecology in environmental and geographical investigations by facilitating analysis of the effects of landscape patterns on...
Long-term climate patterns in Alaskan surface temperature and precipitation and their biological consequences
James J. Simpson, Gary L. Hufford, Michael D. Fleming, Jared S. Berg, J.B. Ashton
2002, IEEE Transactions on Geoscience and Remote Sensing (40) 1164-1184
Mean monthly climate maps of Alaskan surface temperature and precipitation produced by the parameter-elevation regression on independent slopes model (PRISM) were analyzed. Alaska is divided into interior and coastal zones with consistent but different climatic variability separated by a transition region; it has maximum interannual variability but low long-term mean...
Control of strong ground motion of mining-induced earthquakes by the strength of the seismogenic rock mass
Art McGarr
2002, Journal of the South African Institute of Mining and Metallurgy (102) 225-229
The shear stress ?? that can be sustained by the rock mass in the environs of a mining-induced earthquake controls the near-fault peak ground velocity v of that event according to v???0.25(??/G) ??, where ?? is the shear wave speed and G is the modulus of rigidity. To estimate ??...
Tectonics and distribution of gold deposits in China - An overview
T. Zhou, Richard J. Goldfarb, Neil G. Phillips
2002, Mineralium Deposita (37) 249-282
Gold exploration in China has expanded rapidly during the last two decades since a modern approach to economic development has become a national priority. China currently produces 180 tonnes (t) of gold annually, which is still significantly less than South Africa, USA, and Australia. However, China is now recognized as possessing...
A statistical evaluation of non-ergodic variogram estimators
F.C. Curriero, M.E. Hohn, A.M. Liebhold, S.R. Lele
2002, Environmental and Ecological Statistics (9) 89-110
Geostatistics is a set of statistical techniques that is increasingly used to characterize spatial dependence in spatially referenced ecological data. A common feature of geostatistics is predicting values at unsampled locations from nearby samples using the kriging algorithm. Modeling spatial dependence in sampled data is necessary before kriging and is...
Fish communities of the Sacramento River Basin: Implications for conservation of native fishes in the Central Valley, California
J. T. May, L. R. Brown
2002, Environmental Biology of Fishes (63) 373-388
The associations of resident fish communities with environmental variables and stream condition were evaluated at representative sites within the Sacramento River Basin, California between 1996 and 1998 using multivariate ordination techniques and by calculating six fish community metrics. In addition, the results of the current study were compared with recent...
Regional estimates of radiated seismic energy
J. Boatwright, G. L. Choy, L. C. Seekins
2002, Bulletin of the Seismological Society of America (92) 1241-1255
We revise the spectral technique for estimating radiated energy from recordings of large earthquakes at regional distances (Δ < 200 km) by correcting for geometric spreading and for site amplification as explicit functions of frequency. We analyze 65 recordings of the 1999 Hector Mine earthquake as functions of frequency, distance,...
Preliminary comparison of landscape pattern-normalized difference vegetation index (NDVI) relationships to central plains stream conditions
J. A. Griffith, E. A. Martinko, J. L. Whistler, K. P. Price
2002, Journal of Environmental Quality (31) 846-859
We explored relationships of water quality parameters with landscape pattern metrics (LPMs), land use–land cover (LULC) proportions, and the advanced very high resolution radiometer (AVHRR) normalized difference vegetation index (NDVI) or NDVI-derived metrics. Stream sites (271) in Nebraska, Kansas, and Missouri were sampled for water quality parameters, the index of...
The shaping of continental slopes by internal tides
D.A. Cacchione, Lincoln F. Pratson, A.S. Ogston
2002, Science (296) 724-727
The angles of energy propagation of semidiurnal internal tides may determine the average gradient of continental slopes in ocean basins (???2 to 4 degrees). Intensification of near-bottom water velocities and bottom shear stresses caused by reflection of semi-diurnal internal tides affects sedimentation patterns and bottom gradients, as indicated by recent...
Effects of disturbance on germination and seedling establishment in a coastal prairie grassland: A test of the competitive release hypothesis
H.M. Jutila, J.B. Grace
2002, Journal of Ecology (90) 291-302
1. We evaluated the responses of native grassland sods to a variety of types of disturbance in order to assess hypotheses about the competitive effects of established vegetation on seed germination and seedling establishment. In particular, we consider whether germination is more responsive to the magnitude and duration of vegetation...
Effect of growth conditions and staining procedure upon the subsurface transport and attachment behaviors of a groundwater protist
R.W. Harvey, N. Mayberry, N.E. Kinner, D.W. Metge, F. Novarino
2002, Applied and Environmental Microbiology (68) 1872-1881
The transport and attachment behaviors of Spumella guttula (Kent), a nanoflagellate (protist) found in contaminated and uncontaminated aquifer sediments in Cape Cod, Mass., were assessed in flowthrough and static columns and in a field injection-and-recovery transport experiment involving an array of multilevel samplers. Transport of S. guttula harvested from low-nutrient...
Moment-tensor solutions estimated using optimal filter theory: Global seismicity, 2000
S.A. Sipkin, C. G. Bufe, M.D. Zirbes
2002, Physics of the Earth and Planetary Interiors (130) 129-142
Moment-tensor solutions, estimated using optimal filter theory, are listed for 324 moderate-to-large size earthquakes that occurred during the year 2000. Published by Elsevier Science B.V....
