Dynamics of prey moving through a predator field: a model of migrating juvenile salmon
J.H. Petersen, D.L. DeAngelis
2000, Mathematical Biosciences (165) 97-114
The migration of a patch of prey through a field of relatively stationary predators is a situation that occurs frequently in nature. Making quantitative predictions concerning such phenomena may be difficult, however, because factors such as the number of the prey in the patch, the spatial length and velocity of...
Leakage of active crater lake brine through the north flank at Rincon de la Vieja volcano, northwest Costa Rica, and implications for crater collapse
K.A. Kempter, G.L. Rowe
2000, Book, Journal of Volcanology and Geothermal Research
The Active Crater at Rincon de la Vieja volcano, Costa Rica, reaches an elevation of 1750 m and contains a warm, hyper-acidic crater lake that probably formed soon after the eruption of the Rio Blanco tephra deposit approximately 3500 years before present. The Active Crater is buttressed by volcanic ridges...
Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems
D.D. MacDonald, C.G. Ingersoll, T.A. Berger
2000, Archives of Environmental Contamination and Toxicology (39) 20-31
Numerical sediment quality guidelines (SQGs) for freshwater ecosystems have previously been developed using a variety of approaches. Each approach has certain advantages and limitations which influence their application in the sediment quality assessment process. In an effort to focus on the agreement among these various published SQGs, consensus-based SQGs were...
Can Atlantic salmon smolt twice? Endocrine and biochemical changes during smolting
J. M. Shrimpton, Bjorn Thrandur Bjornsson, S. D. McCormick
2000, Canadian Journal of Fisheries and Aquatic Sciences (57) 1969-1976
Ecology and conservation of a rare, old-growth-associated canopy lichen in a silvicultural landscape
A.L. Rosso, B. McCune, T. Rambo
2000, Bryologist (103) 117-127
Nephroma occultum Wetm. is a rare, epiphytic lichen associated with old-growth forests of northwestern North America. We describe its distribution, abundance, and habitat within the managed landscape of a southwestern Oregon watershed. Because this species is found mainly in the canopy, we used direct canopy access (tree climbing) in combination...
Effect of stream channel size on the delivery of nitrogen to the Gulf of Mexico
R. B. Alexander, R. A. Smith, G. E. Schwarz
2000, Nature (403) 758-761
An increase in the flux of nitrogen from the Mississippi river during the latter half of the twentieth century has caused eutrophication and chronic seasonal hypoxia in the shallow waters of the Louisiana shelf in the northern Gulf of Mexico. This has led to reductions in species diversity, mortality of...
Reactive uptake of trace metals in the hyporheic zone of a mining- contaminated stream, Pinal Creek, Arizona
C. C. Fuller, J. W. Harvey
2000, Environmental Science & Technology (34) 1150-1155
Significant uptake of dissolved metals occurred by interaction of groundwater and surface water with hyporheic-zone sediments during transport in Pinal Creek, AZ. The extent of trace metal uptake was calculated by mass balance measurements made directly within the hyporheic zone. A conservative solute tracer injected into the...
Connecting with the community: Gone are the days of the stealth researcher
K.R. Goodwin, S.O. Rogers
2000, Fisheries (25) 34
[No abstract available]...
Growth and invasive potential of Sapium sebiferum (Euphorbiaceae) within the coastal prairie region: the effects of soil and moisture regime
T.C. Barrilleaux, J.B. Grace
2000, American Journal of Botany (87) 1099-1106
The introduced tree Sapium sebiferum (Euphorbiaceae) is considered a serious threat to the preservation of the coastal prairie region of Louisiana and Texas, although it is currently uncommon in the western part of the region. The objective of this study was to evaluate the potential effects of location, soils, and...
Effects of roadside transect width on waterfowl and wetland estimates
Jane E. Austin, H. Thomas Sklebar, Glenn R. Guntenspergen, Thomas K. Buhl
2000, Wetlands (20) 660-670
Strip transects located along roads are commonly used to estimate waterfowl populations and characterize associated wetland habitat. We used data collected in May and early June, 1995, on forty-five 40-km2 plots in North Dakota to evaluate bias of 800-m and 400-m wide roadside transects for sampling wetlands relative to a...
Landscape correlates of breeding bird richness across the United States mid-Atlantic region
K. Bruce Jones, Anne Neale, Nash Maliha, Kurt H. Riitters, James D. Wickham, Robert V. O’Neill, Rick D. van Remortel
2000, Conference Paper, Environmental Monitoring and Assessment
Using a new set of landscape indicator data generated by the U.S.EPA, and a comprehensive breeding bird database from the National Breeding Bird Survey, we evaluated associations between breeding bird richness and landscape characteristics across the entire mid-Atlantic region of the United States. We evaluated how these relationships varied among...
Middle- and late-Wisconsin paleobotanic and paleoclimatic records from the southern Colorado Plateau, USA
R. Scott Anderson, J.L. Betancourt, J.I. Mead, R.H. Hevly, D.P. Adam
2000, Conference Paper, Palaeogeography, Palaeoclimatology, Palaeoecology
The Colorado Plateau is a distinct physiographic province in western North America, which presently straddles the transition between summer-wet and summer-dry climatic regimes to the south and northwest, respectively. In addition to climate, the diversity of environments and plant communities on the Colorado Plateau has resulted from extreme topographic diversity....
Sedimentary and upper crustal structure of Australia from receiver functions
G. Clitheroe, O. Gudmundsson, B.L.N. Kennett
2000, Australian Journal of Earth Sciences (47) 209-216
The initial coda of teleseismic P-waves contains considerable information about the crust and upper mantle structure directly beneath a receiver. When this information can be recovered for a dense network of seismographs much can be learned about the structure of the earth. Data from the high quality broadband seismic stations...
Phreatophyte influence on reductive dechlorination in a shallow aquifer contaminated with trichloroethene (TCE)
R. W. Lee, S.A. Jones, E. L. Kuniansky, G. Harvey, B.S. Lollar, G.F. Slater
2000, International Journal of Phytoremediation (2) 193-211
Phytoremediation uses the natural ability of plants to degrade contaminants in groundwater. A field demonstration designed to remediate aerobic shallow groundwater contaminated with trichloroethene began in April 1996 with the planting of cottonwood trees, a short-rotation woody crop, over an approximately 0.2-ha area at the Naval Air Station, Fort Worth,...
Detection of tetrabromobisphenol a and formation of brominated 13C-bisphenol A'S in commercial drinking water stored in reusable polycarbonate containers
P.H. Peterman, C.E. Orazio, R.W. Gale
2000, ACS Division of Environmental Chemistry, Preprints (40) 431-433
[No abstract available]...
Occurrence of cotton herbicides and insecticides in playa lakes of the High Plains of West Texas
E.M. Thurman, K.C. Bastian, T. Mollhagen
2000, Science of Total Environment (248) 189-200
During the summer of 1997, water samples were collected and analyzed for pesticides from 32 playa lakes of the High Plains that receive drainage from both cotton and corn agriculture in West Texas. The major cotton herbicides detected in the water samples were diuron, fluometuron, metolachlor, norflurazon, and prometryn. Atrazine...
On rate-state and Coulomb failure models
J. Gomberg, N. Beeler, M. Blanpied
2000, Journal of Geophysical Research B: Solid Earth (105) 7857-7871
We examine the predictions of Coulomb failure stress and rate-state frictional models. We study the change in failure time (clock advance) Δt due to stress step perturbations (i.e., coseismic static stress increases) added to "background" stressing at a constant rate (i.e., tectonic loading) at time t0. The predictability of Δt...
Energy budgets of mining-induced earthquakes and their interactions with nearby stopes
Art McGarr
2000, Conference Paper, International Journal of Rock Mechanics and Mining Sciences
In the early 1960's, N.G.W. Cook, using an underground network of geophones, demonstrated that most Witwatersrand tremors are closely associated with deep level gold mining operations. He also showed that the energy released by the closure of the tabular stopes at depths of the order of 2 km was more...
Finding minimal herbicide concentrations in ground water? Try looking for their degradates
D.W. Kolpin, E.M. Thurman, S. M. Linhart
2000, Science of the Total Environment (248) 115-122
Extensive research has been conducted regarding the occurrence of herbicides in the hydrologic system, their fate, and their effects on human health and the environment. Few studies, however, have considered herbicide transformation products (degradates). In this study of Iowa ground water, herbicide degradates were frequently detected. In fact, herbicide degradates...
Identifying predators and fates of grassland passerine nests using miniature video cameras
Pamela J. Pietz, Diane A. Granfors
2000, Journal of Wildlife Management (64) 71-87
Nest fates, causes of nest failure, and identities of nest predators are difficult to determine for grassland passerines. We developed a miniature video-camera system for use in grasslands and deployed it at 69 nests of 10 passerine species in North Dakota during 1996-97. Abandonment rates were higher at nests <1...
Acute toxicity of fire-control chemicals, nitrogenous chemicals, and surfactants to rainbow trout
Kevin J. Buhl, Steven J. Hamilton
2000, Transactions of the American Fisheries Society (129) 408-418
Laboratory studies were conducted to determine the acute toxicity of three ammonia-based fire retardants (Fire-Trol LCA-F, Fire-Trol LCM-R, and Phos-Chek 259F), five surfactant-based fire-suppressant foams (FireFoam 103B, FireFoam 104, Fire Quench, ForExpan S, and Pyrocap B-136), three nitrogenous chemicals (ammonia, nitrate, and nitrite), and two anionic surfactants (linear alkylbenzene sulfonate...
Map data in support of forest management
E. A. Fosnight, D. Greenlee
2000, Journal of Forestry (98) 50-52
Now widely available and inexpensive, prepackaged map data are easy to use--and just as easy to use incorrectly. To select the proper scale and appropriate thematic attributes so that the data actually inform the project at hand, managers need to know the basics....
Multiple large earthquakes in the past 1500 years on a fault in metropolitan Manila, the Philippines
A.R. Nelson, S. F. Personius, R.E. Rimando, R.S. Punongbayan, N. Tungol, H. Mirabueno, A. Rasdas
2000, Bulletin of the Seismological Society of America (90) 73-85
The first 14C-based paleoseismic study of an active fault in the Philippines shows that a right-lateral fault on the northeast edge of metropolitan Manila poses a greater seismic hazard than previously thought. Faulted hillslope colluvium, stream-channel alluvium, and debris-flow deposits exposed in trenches across the northern part of the west Marikina...
Fish as vectors in the dispersal of Bythotrephes cederstroemi: Diapausing eggs survive passage through the gut
S.T. Jarnagin, B.K. Swan, W.C. Kerfoot
2000, Freshwater Biology (43) 579-589
1. Bythotrephes cederstroemi (Crustacea: Onychopoda: Cercopagidae) is an introduced invertebrate predator currently spreading through the Laurentian Great Lakes region of North America. We examined a previously unsuspected way in which B. cederstroemi may be dispersed by fish by their consumption of diapausing eggs. 2. Ninety-four percentage of the mature B....
Past leaded gasoline emissions as a nonpoint source tracer in riparian systems: A study of river inputs to San Francisco Bay
C.E. Dunlap, R. Bouse, A.R. Flegal
2000, Environmental Science & Technology (34) 1211-1215
Variations in the isotopic composition of lead in 1995-1998 river waters flowing into San Francisco Bay trace the washout of lead deposited in the drainage basin from leaded gasoline combustion. At the confluence of the Sacramento and San Joaquin rivers where they enter the Bay, the isotopic compositions of lead...
