Growth, biomass allocation and nutrient use efficiency in Cladium jamaicense and Typha domingensis as affected by phosphorus and oxygen availability
B. Lorenzen, H. Brix, I.A. Mendelssohn, K.L. McKee, S.L. Miao
2001, Aquatic Botany (70) 117-133
The effects of phosphorus (P) and oxygen availability on growth, biomass allocation and nutrient use efficiency in Cladium jamaicense Crantz and Typha domingensis Pers. were studied in a growth facility equipped with steady-state hydroponic rhizotrons. The treatments included four P concentrations (10, 40, 80 and 500 ??g I-1) and two...
Mapping wildland fuels for fire management across multiple scales: integrating remote sensing, GIS, and biophysical modeling
Robert E. Keane, Robert E. Burgan, Jan W. Van Wagtendonk
2001, International Journal of Wildland Fire (10) 301-319
Fuel maps are essential for computing spatial fire hazard and risk and simulating fire growth and intensity across a landscape. However, fuel mapping is an extremely difficult and complex process requiring expertise in remotely sensed image classification, fire behavior, fuels modeling, ecology, and geographical information systems (GIS). This paper first...
Standard reference water samples for rare earth element determinations
P. L. Verplanck, Ronald C. Antweiler, D. Kirk Nordstrom, Howard E. Taylor
2001, Applied Geochemistry (16) 231-244
Standard reference water samples (SRWS) were collected from two mine sites, one near Ophir, CO, USA and the other near Redding, CA, USA. The samples were filtered, preserved, and analyzed for rare earth element (REE) concentrations (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb,...
Sexual segregation in Roosevelt Elk: Cropping rates and aggression in mixed sex groups
Floyd F. Weckerly, Mark A. Ricca, Katherin P. Meyer
2001, Journal of Mammalogy (82) 825-835
Few studies of sexual segregation in ruminants have tested widely invoked mechanisms of segregation in mixed-sex groups. In a sexually segregated population of Roosevelt elk (Cervus elaphus roosevelti), we examined if adult males had reduced intake of forage when in mixed-sex groups and if intersexual differences in aggression caused females...
Fish species composition two second-order headwater streams the North Central Appalachians ecoregion
M. N. DiLauro, R. M. Bennett
2001, Journal of Freshwater Ecology (16) 35-43
Fish species composition was determined for two second-order headwater streams within the North Central Appalachians ecoregion in northern Pennsylvania. The two streams were widely spaced geographically (over 193 km apart) and occurred in different drainage systems. Streams were sampled in the spring and fall over two years (1996–98) yielding similar...
Dating the Vostok ice core record by importing the Devils Hole chronology
J.M. Landwehr, I.J. Winograd
2001, Journal of Geophysical Research D: Atmospheres (106) 31853-31861
The development of an accurate chronology for the Vostok record continues to be an open research question because these invaluable ice cores cannot be dated directly. Depth-to-age relationships have been developed using many different approaches, but published age estimates are inconsistent, even for major paleoclimatic events. We have developed a...
Snapping turtles (Chelydra serpentina) as monitors for mercury contamination of aquatic environments
W.J. Golet, T.A. Haines
2001, Environmental Monitoring and Assessment (71) 211-220
We assessed the distribution of mercury in snapping turtles (Chelydra serpentina) by analyzing front shoulder muscle, back leg muscle, tail muscle, blood, liver, and marginal carapacial scute (shell) of 26 adult turtles from five small lakes. Total mercury concentration in muscle ranged from 50 to500 ng g−1 wet weight and was...
A portfolio approach to evaluating natural hazard mitigation policies: An application to lateral-spread ground failure in coastal California
R. L. Bernknopf, L.B. Dinitz, S.J.M. Rabinovici, A.M. Evans
2001, International Geology Review (43) 424-440
In the past, efforts to prevent catastrophic losses from natural hazards have largely been undertaken by individual property owners based on site—specific evaluations of risks to particular buildings. Public efforts to assess community vulnerability and encourage mitigation have focused on either aggregating site—specific estimates or adopting standards based upon broad...
Birds at a Southern California beach: seasonality, habitat use and disturbance by human activity
Kevin D. Lafferty
2001, Biodiversity and Conservation (10) 1949-1962
Use of a Santa Barbara beach by people and birds varied in both time and space. There were 100 birds, 18 people and 2 dogs per kilometer. Bird density varied primarily with the season and tide while human activity varied most between weekend and weekday. Bird distributions along the beach...
Disturbance to wintering western snowy plovers
Kevin D. Lafferty
2001, Biological Conservation (101) 315-325
In order to better understand the nature of disturbances to wintering snowy plovers, I observed snowy plovers and activities that might disturb them at a beach near Devereux Slough in Santa Barbara, California, USA. Disturbance (activity that caused plovers to move or fly) to wintering populations of threatened western snowy...
New digital magnetic anomaly database for North America
C. A. Finn, M. Pilkington, A. Cuevas, I. Hernandez, Jaime Urrutia
2001, The Leading Edge (20) 870-872
The Geological Survey of Canada (GSC), U.S. Geological Survey (USGS), and Consejo de Recursos Minerales of Mexico (CRM) are compiling an upgraded digital magnetic anomaly database and map for North America. This trinational project is expected to be completed by late 2002....
The geology and palynology of lower and Middle Pennsylvanian strata in the Western Kentucky Coal Field
C.F. Eble, S.F. Greb, D.A. Williams
2001, International Journal of Coal Geology (47) 189-206
The Western Kentucky Coal Field is the southern tip of the Eastern Interior, or Illinois Basin. Pennsylvanian rocks in this area, which include conglomerate, sandstone, shale, limestone and coal, were deposited primarily in coastal-deltaic settings at a time when western Kentucky was located close to the equator. This paper discusses...
Statistical self-similarity of hotspot seamount volumes modeled as self-similar criticality
S.F. Tebbens, S.M. Burroughs, C.C. Barton, D. F. Naar
2001, Geophysical Research Letters (28) 2711-2714
The processes responsible for hotspot seamount formation are complex, yet the cumulative frequency-volume distribution of hotspot seamounts in the Easter Island/Salas y Gomez Chain (ESC) is found to be well-described by an upper-truncated power law. We develop a model for hotspot seamount formation where uniform energy input produces events initiated...
Managing exotic grasses and conserving declining species
D.J. Germano, G. B. Rathbun, L.R. Saslaw
2001, Wildlife Society Bulletin (29) 551-559
Experimental repatriation of boreal toad (Bufo boreas) eggs, metamorphs, and adults in Rocky Mountain National Park
E. Muths, T. L. Johnson, P.S. Corn
2001, Southwestern Naturalist (46) 106-113
The boreal toad (Bufo boreas) is an endangered species in Colorado and is considered a candidate species for federal listing by the United States Fish and Wildlife Service. Boreal toads are absent from many areas of suitable habitat in the Southern Rocky Mountains of Colorado presumably due to a combination...
Decreased glutathione S-transferase expression and activity and altered sex steroids in Lake Apopka brown bullheads (Ameriurus nebulosus)
E.P. Gallagher, T. S. Gross, K.M. Sheehy
2001, Aquatic Toxicology (55) 223-237
A number of freshwater lakes and reclaimed agricultural sites in Central Florida have been the receiving waters for agrochemical and municipal runoff. One of these sites, Lake Apopka, is also a eutrophic system that has been the focus of several case studies reporting altered reproductive activity linked to bioaccumulation of...
Sex differences in territorial behavior exhibited by the spotted hyena (Hyaenidae, Crocuta crocuta)
Erin E. Boydston, Toni Lyn Morelli, Kay E. Holekamp
2001, Ethology (107) 369-385
Spotted hyenas (Crocuta crocuta) are gregarious carnivores that defend group territories against encroachment by neighboring conspecifics. Here we monitored the behavior of members of one clan of free-ranging spotted hyenas during border patrols, ‘wars’ with neighboring clans, and other interactions with alien intruders, to document differences between the sexes in...
Utility of stable isotope analysis in studying foraging ecology of herbivores: Examples from moose and caribou
Merav Ben-David, Einav Shochat, Layne G. Adams
2001, Alces (37) 421-434
Recently, researchers emphasized that patterns of stable isotope ratios observed at the individual level are a result of an interaction between ecological, physiological, and biochemical processes. Isotopic models for herbivores provide additional complications because those mammals consume foods that have high variability in nitrogen concentrations. In addition, distribution of amino...
Recent formation of arroyos in the Little Missouri Badlands of southwestern North Dakota
M.A. Gonzalez
2001, Geomorphology (38) 63-84
In the Little Missouri Badlands of southwestern North Dakota, the channels of ephemeral streams are incised 2 to 10 m or more into mid-to-late Holocene alluvium. The objectives of this study were to determine the timing and cause(s) of the most recent episodes of fluvial incision and to develop a...
Declining ring-necked pheasants in the Klamath Basin, California: II. Survival, productivity, and cover
Robert A. Grove, D. R. Buhler, Charles J. Henny, A. D. Drew
2001, Northwestern Naturalist (82) 85-101
Cover condition and its influence on nesting success, survival, and body condition of ring-necked pheasants (Phasianus colchicus) were evaluated at Tule Lake National Wildlife Refuge (TLNWR) and Lower Klamath National Wildlife Refuge (LKNWR). Inadequate nesting cover was responsible for extremely low nest success early in the nesting season at TLNWR....
Distribution of inorganic mercury in Sacramento River water and suspended colloidal sediment material
D.A. Roth, Howard E. Taylor, Joseph L. Domagalski, Peter D. Dileanis, D.B. Peart, Ronald C. Antweiler, Charles N. Alpers
2001, Archives of Environmental Contamination and Toxicology (40) 161-172
The concentration and distribution of inorganic Hg was measured using cold-vapor atomic fluorescence spectrometry in samples collected at selected sites on the Sacramento River from below Shasta Dam to Freeport, CA, at six separate times between 1996 and 1997. Dissolved (ultrafiltered, 0.005 μm equivalent pore size) Hg concentrations remained...
Evolution of soils on quaternary reef terraces of Barbados, West Indies
D.R. Muhs
2001, Quaternary Research (56) 66-78
Soils on uplifted Quaternary reef terraces of Barbados, ???125,000 to ???700,000 yr old, form a climo-chronosequence and show changes in physical, chemical, and mineralogical properties with terrace age. Parent materials are dust derived from the Sahara, volcanic ash from the Lesser Antilles island arc, and detrital carbonate from the underlying...
Mourning dove productivity in California during 1992-95: Was it sufficient to balance mortality?
M. R. Miller, C.L. Stemler, S.D. Blankenship
2001, Journal of Wildlife Management (65) 300-311
Mourning dove (Zenaida macroura) populations have declined steadily in the western United States since 1966. We investigated the role of recruitment in this long-term problem by studying nesting ecology of mourning doves from March to September 1992-95, in the northern Central Valley, California, USA. We studied nesting doves in blue...
Gut contents of juvenile chinook salmon from the upper sacramento river, California during spring 1998
B.A. Martin, M. K. Saiki
2001, California Fish and Game (87) 38-43
[No abstract available]...
Use of passive ambient ozone (O3) samplers in vegetation effects assessment
S. Krupa, M. Nosal, D. L. Peterson
2001, Environmental Pollution (112) 303-309
A stochastistic, Weibull probability model was developed and verified to simulate the underlying frequency distributions of hourly ozone (O3) concentrations (exposure dynamics) using the single, weekly mean values obtained from a passive (sodium nitrite absorbent) sampler. The simulation was based on the data derived from a co-located continuous monitor. Although...
