Lessons learned from long-term ecosystem research and monitoring in alpine and subalpine basins of the Colorado Rocky Mountains, USA
Jill Baron
2001, Ekologia (Bratislava) (20) 25-30
Long-term ecosystem research and monitoring was begun in the Loch Vale watershed of Rocky Mountain National Park in 1983, after extensive survey work to identify the best location. Then, as now, our scientific objectives were to understand natural biogeochemical cycles and variability, so that we could differentiate ecosystem changes from...
Constraints on dike propagation from continuous GPS measurements
P. Segall, Peter Cervelli, S. Owen, M. Lisowski, Asta Mikijus
2001, Journal of Geophysical Research B: Solid Earth (106) 19301-19317
The January 1997 East Rift Zone eruption on Kilauea volcano, Hawaii, occurred within a network of continuous Global Positioning System (GPS) receivers. The GPS measurements reveal the temporal history of deformation during dike intrusion, beginning ∼8 hours prior to the onset of the eruption. The dike volume as a function...
Sample-size requirements for evaluating population size structure
J.C. Vokoun, C.F. Rabeni, J.S. Stanovick
2001, North American Journal of Fisheries Management (21) 660-665
A method with an accompanying computer program is described to estimate the number of individuals needed to construct a sample length-frequency with a given accuracy and precision. First, a reference length-frequency assumed to be accurate for a particular sampling gear and collection strategy was constructed. Bootstrap procedures created length-frequencies with...
Empirical assessment of indices of prey importance in the diets of predacious fish
H. Liao, C.L. Pierce, J. G. Larscheid
2001, Transactions of the American Fisheries Society (130) 583-591
Determining the importance of prey taxa in the diets of predacious species is a frequent objective in fisheries research. Various indices of prey importance are in common use, and all give different results because of their emphasis on different aspects of fish diets. We explored these differences by empirically comparing...
Seismic-reflection imaging of Tertiary faulting and related post-Eocene deformation 20 km North of Memphis, Tennessee
R. A. Williams, W. J. Stephenson, J. K. Odum, D. M. Worley
2001, Engineering Geology (62) 79-90
Other than the Crittenden County fault zone (CCFZ), little is known about the seismic hazard from earthquake faults within 50 km of Memphis, Tennessee, a city that contains a large inventory of older buildings that are vulnerable to moderate and strong earthquake ground shaking. To address this lack of knowledge...
Comparison of soil infiltration rates in burned and unburned mountainous watersheds
D.A. Martin, J. A. Moody
2001, Hydrological Processes (15) 2893-2903
Steady-state infiltration measurements were made at mountainous sites in New Mexico and Colorado, USA, with volcanic and granitic soils after wildfires and at comparable unburned sites. We measured infiltration in the New Mexico volcanic soils under two vegetation types, ponderosa pine and mixed conifer, and in the Colorado granitic soils...
Reproductive ecology and demography of the 'Akohekohe
John C. Simon, Thane K. Pratt, Kim E. Berlin, James R. Kowalsky
2001, Condor (103) 736-745
The ‘Ākohekohe (Palmeria dolei) is an endangered Hawaiian honeycreeper endemic to the montane rain forests of east Maui in the Hawaiian Islands. We investigated ‘Ākohekohe nesting ecology using color-banded birds for the first time as a background to understanding the species' conservation. From 1994–1997, we color-banded 78 individuals, located and...
Volcano monitoring using the Global Positioning System: Filtering strategies
K.M. Larson, Peter Cervelli, M. Lisowski, Asta Mikijus, P. Segall, S. Owen
2001, Journal of Geophysical Research B: Solid Earth (106) 19453-19464
Permanent Global Positioning System (GPS) networks are routinely used for producing improved orbits and monitoring secular tectonic deformation. For these applications, data are transferred to an analysis center each day and routinely processed in 24-hour segments. To use GPS for monitoring volcanic events, which may last only a few hours,...
Evidence that coded-wire-tagging procedures can enhance transmission of Renibacterium salmoninarum in chinook salmon
D.G. Elliott, R.J. Pascho
2001, Journal of Aquatic Animal Health (13) 181-193
Binary coded wire tags (CWTs) are used extensively for identification and management of anadromous salmonid populations. A study of bacterial kidney disease (BKD) in two brood year groups of hatchery-reared spring chinook salmon Oncorhynchus tshawytscha provided strong evidence that horizontal transmission of Renibacterium salmoninarum, the causative agent of BKD, might...
A metadata initiative for global information discovery
E. Christian
2001, Government Information Quarterly (18) 209-221
The Global Information Locator Service (GILS) encompasses a global vision framed by the fundamental values of open societies. Societal values such as a free flow of information impose certain requirements on the society's information infrastructure. These requirements in turn shape the various laws, policies, standards, and technologies that determine the...
Geochemical and mineralogical controls on trace element release from the Penn Mine base-metal slag dump, California
M.B. Parsons, D.K. Bird, M.T. Einaudi, Charles N. Alpers
2001, Applied Geochemistry (16) 1567-1593
Base-metal slag deposits at the Penn Mine in Calaveras County, California, are a source of environmental contamination through leaching of potentially toxic elements. Historical Cu smelting at Penn Mine (1865-1919) generated approximately 200,000 m3 of slag. The slag deposits, which are flooded annually by a reservoir used for drinking water...
Calibration of the DRASTIC ground water vulnerability mapping method
M.G. Rupert
2001, Ground Water (39) 625-630
Ground water vulnerability maps developed using the DRASTIC method have been produced in many parts of the world. Comparisons of those maps with actual ground water quality data have shown that the DRASTIC method is typically a poor predictor of ground water contamination. This study significantly improved the effectiveness of...
Effect of scale on the behavior of atrazine in surface waters
P. D. Capel, S.J. Larson
2001, Environmental Science & Technology (35) 648-657
Field runoff is an important transport mechanism by which agricultural pesticides, including atrazine, move into the hydrologic environment. Atrazine is chosen because it is widely used, is transported in runoff relatively easily, is widely observed in surface waters, and has relatively little loss in the stream network. Data on runoff...
Application of a nonlinear slug test model
C.D. McElwee
2001, Ground Water (39) 737-744
Knowledge of the hydraulic conductivity distribution is of utmost importance in understanding the dynamics of an aquifer and in planning the consequences of any action taken upon that aquifer. Slug tests have been used extensively to measure hydraulic conductivity in the last 50 years since Hvorslev's (1951) work. A general...
Determination of variables in the prediction of strontium distribution coefficients for selected sediments
M.N. Pace, J.J. Rosentreter, R. C. Bartholomay
2001, Environmental Geology (40) 993-1002
Idaho State University and the US Geological Survey, in cooperation with the US Department of Energy, conducted a study to determine and evaluate strontium distribution coefficients (Kds) of subsurface materials at the Idaho National Engineering and Environmental Laboratory (INEEL). The Kds were determined to aid in assessing the variability of...
Elevated carbon dioxide flux at the Dixie Valley geothermal field, Nevada; relations between surface phenomena and the geothermal reservoir
D. Bergfeld, F. Goff, C. J. Janik
2001, Chemical Geology (177) 43-66
In the later part of the 1990s, a large die-off of desert shrubs occurred over an approximately 1 km2 area in the northwestern section of the Dixie Valley (DV) geothermal field. This paper reports results from accumulation-chamber measurements of soil CO2 flux from locations in the dead zone and stable...
Soil efflux and total emission rates of magmatic CO2 at the horseshoe lake tree kill, mammoth mountain, California, 1995-1999
T.M. Gerlach, M.P. Doukas, K.A. McGee, R. Kessler
2001, Chemical Geology (177) 101-116
We report the results of eight soil CO2 efflux surveys by the closed circulation chamber method at the Horseshoe Lake tree kill (HLTK) - the largest tree kill on Mammoth Mountain. The surveys were undertaken from 1995 to 1999 to constrain total HLTK CO2 emissions and to evaluate occasional efflux...
U.S. Geological Survey programs and investigations related to soil and water conservation
W. R. Osterkamp, J. R. Gray
2001, International Journal of Sediment Research (16) 421-429
The U.S. Geological Survey has a rich tradition of collecting hydrologic data, especially for fluxes of water and suspended sediment, that provide a foundation for studies of soil and water conservation. Applied and basic research has included investigations of the effects of land use on rangelands, croplands, and forests; hazards...
Enhanced algorithm performance for land cover classification from remotely sensed data using bagging and boosting
J.C.-W. Chan, C. Huang, R. DeFries
2001, IEEE Transactions on Geoscience and Remote Sensing (39) 693-695
Two ensemble methods, bagging and boosting, were investigated for improving algorithm performance. Our results confirmed the theoretical explanation [1] that bagging improves unstable, but not stable, learning algorithms. While boosting enhanced accuracy of a weak learner, its behavior is subject to the characteristics of each learning algorithm....
Developing a geomorphic approach for ranking watersheds for rehabilitation, Zuni Indian Reservation, New Mexico
A. C. Gellis, A. Cheama, S.M. Lalio
2001, Geomorphology (37) 105-134
As a result of past erosion problems on the Zuni Indian Reservation in western New Mexico, the US Congress in 1990 authorized the Zuni Tribe to begin a program for watershed rehabilitation. This paper describes an approach to rank the most appropriate watersheds for rehabilitation for the Zuni Reservation. The...
Contribution of base flow to nonpoint source pollution loads in an agricultural watershed
K. E. Schilling, C.F. Wolter
2001, Ground Water (39) 49-58
Nonpoint source pollution of surface water from overland flow, drainage tiles, and ground water discharge is a major cause of water quality impairment in Iowa. Nonpoint source pollution from base flow ground water was estimated in the Walnut Creek watershed by measuring chemical loads of atrazine, nitrate, chloride, and sulfate...
A simple algorithm for sequentially incorporating gravity observations in seismic traveltime tomography
T. Parsons, R.J. Blakely, T.M. Brocher
2001, International Geology Review (43) 1073-1086
The geologic structure of the Earth's upper crust can be revealed by modeling variation in seismic arrival times and in potential field measurements. We demonstrate a simple method for sequentially satisfying seismic traveltime and observed gravity residuals in an iterative 3-D inversion. The algorithm is portable to any seismic analysis...
Potential artifacts in interpretation of differential breakthrough of colloids and dissolved tracers in the context of transport in a zero-valent iron permeable reactive barrier
P. Zhang, W.P. Johnson, M.J. Piana, C. C. Fuller, D. L. Naftz
2001, Ground Water (39) 831-840
Many published studies have used visual comparison of the timing of peak breakthrough of colloids versus conservative dissolved tracers (hereafter referred to as dissolved tracers or tracers) in subsurface media to determine whether they are advected differently, and to elucidate the mechanisms of differential advection. This purely visual approach of...
Interactive visualization of vegetation dynamics
B. C. Reed, D. Swets, L. Bard, J. Brown, James Rowland
2001, Conference Paper, International Geoscience and Remote Sensing Symposium (IGARSS)
Satellite imagery provides a mechanism for observing seasonal dynamics of the landscape that have implications for near real-time monitoring of agriculture, forest, and range resources. This study illustrates a technique for visualizing timely information on key events during the growing season (e.g., onset, peak, duration, and end of growing season),...
Habitat fragmentation effects on birds in grasslands and wetlands: A critique of our knowledge
Douglas H. Johnson
2001, Great Plains Research (11) 211-231
Habitat fragmentation exacerbates the problem of habitat loss for grassland and wetland birds. Remaining patches of grasslands and wetlands may be too small, too isolated, and too influenced by edge effects to maintain viable populations of some breeding birds. Knowledge of the effects of fragmentation on bird populations is critically...
