Conference Papers
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Overview of Pacific Island carbonate beach systems Overview of Pacific Island carbonate beach systems
Beach systems in Pacific Islands are Holocene deposits of reef-dervied and terrigenous sediment. Thus, geologic setting is important in determining the success at which beach systems are established. Generally, older islands exhibit better beach system development. Although modern beach systems are composed of Holocene sediment, development of suitable accommodation space requires more...
Authors
B. M. Richmond
Palaeohydrology, vegetation, and climate since the late Illinois Episode (~130 ka) in south-central Illinois Palaeohydrology, vegetation, and climate since the late Illinois Episode (~130 ka) in south-central Illinois
Our interpretation of pollen and ostracode successions from four basins in south-central Illinois provides a new synthesis of palaeovegetation, palaeohydrology, and palaeoclimate for the period from the late Illinois Episode (about 130,000 years ago) to near the end of the Wisconsin Episode (about 25,000 years ago). Correlations of pollen biozones between Raymond, Pittsburg, and Bald...
Authors
B. Brandon Curry, R. G. Baker
Paleoclimate reconstruction along the Pole-Equator-Pole transect of the Americas (PEP 1) Paleoclimate reconstruction along the Pole-Equator-Pole transect of the Americas (PEP 1)
Examples are presented of inter-hemispheric comparison of instrumental climate and paleoclimate proxy records from the Americas for different temporal scales. Despite a certain symmetry of seasonal precipitation patterns along the PEP I transect, decadal variability of winter precipitation shows different characteristics in terms of amplitude and frequency in both the last 100 and last...
Authors
Vera Markgraf, T.R. Baumgartner, J.P. Bradbury, Henry F. Diaz, R. B. Dunbar, B.H. Luckman, G.O. Seltzer, T.W. Swetnam, R. Villalba
Paradigm shifts in theory and methods: regression quantile analysis enables new insights for ecology Paradigm shifts in theory and methods: regression quantile analysis enables new insights for ecology
No abstract available.
Authors
C.E. Bock, Brian S. Cade
Pesticide transport in the San Joaquin River Basin Pesticide transport in the San Joaquin River Basin
Pesticide occurrence and concentrations were evaluated in the San Joaquin River Basin to determine potential sources and mode of transport. Land use in the basin is mainly agricultural. Spatial variations in pesticide occurrence were evaluated in relation to pesticide application and cropping patterns in three contrasting subbasins and at the mouth of the basin. Temporal variability in...
Authors
Neil M. Dubrovsky, Charles R. Kratzer, Sandra Y. Panshin, JoAnn M. Gronberg, Kathryn M. Kuivila
Physical modeling of a prototype slim-hold time-domain dielectric logging tool Physical modeling of a prototype slim-hold time-domain dielectric logging tool
No abstract available.
Authors
J.D. Abraham
Predictive modelling of flow in a two-dimensional intermediate-scale, heterogeneous porous media Predictive modelling of flow in a two-dimensional intermediate-scale, heterogeneous porous media
To better understand the role of sedimentary structures in flow through porous media, and to determine how small-scale laboratory-measured values of hydraulic conductivity relate to in situ values this work deterministically examines flow through simple, artificial structures constructed for a series of intermediate-scale (10 m long), two-dimensional, heterogeneous, laboratory...
Authors
Gilbert R. Barth, M. C. Hill, T.H. Illangasekare, H. Rajaram
Preface paper to the Semi-Arid Land-Surface-Atmosphere (SALSA) Program special issue Preface paper to the Semi-Arid Land-Surface-Atmosphere (SALSA) Program special issue
The Semi-Arid Land-Surface-Atmosphere Program (SALSA) is a multi-agency, multi-national research effort that seeks to evaluate the consequences of natural and human-induced environmental change in semi-arid regions. The ultimate goal of SALSA is to advance scientific understanding of the semi-arid portion of the hydrosphere-biosphere interface in order to provide reliable information for
Authors
D.C. Goodrich, A. Chehbouni, B. Goff, B. MacNish, T. Maddock, S. Moran, W.J. Shuttleworth, D. G. Williams, C. Watts, L.H. Hipps, D.I. Cooper, J. Schieldge, Y.H. Kerr, H. Arias, M. Kirkland, R. Carlos, P. Cayrol, W. Kepner, B. Jones, R. Avissar, A. Begue, J.-M. Bonnefond, G. Boulet, B. Branan, J.P. Brunel, L.C. Chen, T. Clarke, M.R. Davis, H. DeBruin, G. Dedieu, E. Elguero, W.E. Eichinger, J. Everitt, J. Garatuza-Payan, V.L. Gempko, H. Gupta, C. Harlow, O. Hartogensis, M. Helfert, C. Holifield, D. Hymer, A. Kahle, T. Keefer, S. Krishnamoorthy, J.-P. Lhomme, J.-P. Lagouarde, Seen D. Lo, D. Luquet, R. Marsett, B. Monteny, W. Ni, Y. Nouvellon, R. Pinker, C. Peters, D. Pool, J. Qi, S. Rambal, J. Rodriguez, F. Santiago, E. Sano, S.M. Schaeffer, M. Schulte, R. Scott, X. Shao, K.A. Snyder, S. Sorooshian, C.L. Unkrich, M. Whitaker, I. Yucel
Progress and over-view of current GLFT EMS project: Report on Early Mortality Syndrome Workshop Progress and over-view of current GLFT EMS project: Report on Early Mortality Syndrome Workshop
No abstract available at this time
Authors
J. Fitzsimons, S.B. Brown, D. C. Honeyfield, D. E. Tillitt
Reconnaissance survey of sulfonamide, sulfonylurea, and imidazolinone herbicides in surface streams and groundwater of the Midwestern United States Reconnaissance survey of sulfonamide, sulfonylurea, and imidazolinone herbicides in surface streams and groundwater of the Midwestern United States
The study objective was to conduct a small scale synoptic survey of representative water resources draining agricultural land for occurrence of several herbicide residues. These new classes of herbicides are commonly applied pre-emergence or post-emergence in conservation tillage systems to control grasses and broadleaf weeds in cropped and noncropped areas. Both surface water and...
Authors
T.R. Steinheimer, R.L. Pfeiffer, K.D. Scoggin, W.A. Battaglin
Redox conditions and the efficiency of chlorinated ethene biodegradation: Field studies Redox conditions and the efficiency of chlorinated ethene biodegradation: Field studies
The effect of redox conditions on the efficiency of chlorinated ethene biodegradation was investigated at two field sites. One site (NAS Cecil Field, FL) is characterized by predominantly Fe(III)-reducing conditions in the contaminant source area, grading to predominantly sulfate- reducing conditions downgradient. This sequence of redox conditions led to relatively inefficient...
Authors
F. H. Chapelle, P. M. Bradley
Redox conditions and the efficiency of chlorinated ethene biodegradation: Laboratory studies Redox conditions and the efficiency of chlorinated ethene biodegradation: Laboratory studies
The potential for biodegradation of highly reduced groundwater contaminants is greatest under aerobic conditions and least under CO2-reducing (methanogenic) conditions. Laboratory studies conducted using [1,2-14C] vinyl chloride (VC) indicate the same pattern applies to the anaerobic oxidation of relatively reduced chloroethylenes. Recent studies, showing that CH4 can be a significant...
Authors
P. M. Bradley, F. H. Chapelle