Coupling demography, physiology and evolution in chaparral shrubs,
Jon E. Keeley
P.W. Rundel, G. Montenegro, F.M. Jaksic, editor(s)
1998, Book chapter, Landscape Disturbance and Biodiversity in Mediterranean-Type Ecosystems.
Historically, since fire is a recurrent catastrophic disturbance, mediterranean-climate shrubs have been classified by their mode of postfire regeneration, i.e., obligate seeders, facultative seeders or obligate resprouters. While these terms are useful, they are too restrictive in that they only refer to a species’ response to fire and do not...
Satellite radar interferometry measures deformation at Okmok Volcano
Zhong Lu, Dorte Mann, Jeff Freymueller
1998, Eos, Transactions, American Geophysical Union (79) 461-468
The center of the Okmok caldera in Alaska subsided 140 cm as a result of its February– April 1997 eruption, according to satellite data from ERS-1 and ERS-2 synthetic aperture radar (SAR) interferometry. The inferred deflationary source was located 2.7 km beneath the approximate center of the caldera using a...
Assessing relative abundance and reproductive success of shrubsteppe raptors
Robert N. Lehman, L.B. Carpenter, Karen Steenhof, Michael N. Kochert
1998, Journal of Field Ornithology (69) 244-256
From 1991-1994, we quantified relative abundance and reproductive success of the Ferruginous Hawk (Buteo regalis), Northern Harrier (Circus cyaneus), Burrowing Owl (Speotytoc unicularia), and Short-eared Owl (Asio flammeus) on the shrubsteppe plateaus (benchlands) in and near the Snake River Birds of Prey National Conservation Area in southwestern Idaho. To assess relative abundance, we searched...
A policy model to initiate environmental negotiations: Three hydropower workshops
Berton Lee Lamb, Jonathan G. Taylor, Nina Burkardt, Phadrea D. Ponds
1998, Human Dimensions of Wildlife: An International Journal (3) 1-17
How do I get started in natural resource negotiations? Natural resource managers often face difficult negotiations when they implement laws and policies regulating such resources as water, wildlife, wetlands, endangered species, and recreation. As a result of these negotiations, managers must establish rules, grant permits, or create management plans. The...
Estimator selection for closed-population capture: recapture
Thomas R. Stanley, Kenneth P. Burnham
1998, Journal of Agricultural, Biological, and Environmental Statistics (3) 131-150
For valid statistical inference, it is important to select an appropriate statistical model. In the analysis of capture-recapture data under the closed-population models of Otis et al. (1978), information theoretic and hypothesis testing approaches to model selection are not practical, because some of the models have likelihoods with nonidenti- fiable...
Variability of Secchi disk readings in an exceptionally clear and deep caldera lake
Gary L. Larson, M.W. Buktenica
1998, Archiv fur Hydrobiologie (141) 377-388
SUMMARY: The Peromyscus leucopus on a 17-acre study area were live-trapped, marked, and released over a seven-day period. On the three following nights intensive snap-trapping was done on the central acre of the study plot. The animals caught by snap traps in...
Magmagenesis at Soufriere volcano St Vincent, Lesser Antilles Arc
E. Heath, R. Macdonald, H. Belkin, C. Hawkesworth, Haraldur Sigurdsson
1998, Journal of Petrology (39) 1721-1764
Soufriere volcano of St Vincent (<0.6 Ma) is composed of basalts and basaltic andesites, the most mafic of which (mg-number 75) may be representative of the parental magmas of the calc-alkaline suites of the Lesser Antilles arc. Parental, possibly primary, magmas at Soufriere had MgO ∼12.5 wt % and...
Geodynamics of magmatic Cu-Ni-PGE sulfide deposits: New insights from the Re-Os isotope system
D.D. Lambert, J.G. Foster, L.R. Frick, E.M. Ripley, M. L. Zientek
1998, Economic Geology (93) 121-136
In this study, we reassess crustal contamination and sulfide ore-forming processes in some of the largest magmatic ore deposits, using published Re-Os isotope data and a modeling methodology that incorporates the R factor, defined as the effective mass of silicate magma with which a given mass of sulfide magma has...
Estimate of net trophic transfer efficiency of PCBs to Lake Michigan lake trout from their prey
Charles P. Madenjian, Robert J. Hesselberg, Timothy J. Desorcie, Larry J. Schmidt, Ralph M. Stedman, Richard T. Quintal, Linda J. Begnoche, Dora R. Passino-Reader
1998, Environmental Science & Technology (32) 886-891
Most of the polychlorinated biphenyl (PCB) body burden accumulated by lake trout (Salvelinus namaycush) from the Laurentian Great Lakes is from their food. We used diet information, PCB determinations in both lake trout and their prey, and bioenergetics modeling to estimate the efficiency with which Lake Michigan lake trout retain...
Gill net saturation by lake trout in Michigan waters of Lake Superior
Michael J. Hansen, Richard G. Schorfhaar, James H. Selgeby
1998, North American Journal of Fisheries Management (18) 847-853
We conducted experimental fishing for lake trout Salvelinus namaycush in Michigan waters of Lake Superior to determine the importance of soak time on catch per effort (CPE) in numbers per kilometer of standard gill net. We modeled CPE as a nonlinear function of the number of nights between setting and lifting (soak...
Terrestrial sedimentation and the carbon cycle: Coupling weathering and erosion to carbon burial
Robert F. Stallard
1998, Global Biogeochemical Cycles (12) 231-257
This paper examines the linkages between the carbon cycle and sedimentary processes on land. Available data suggest that sedimentation on land can bury vast quantities of organic carbon, roughly 1015 g C yr−1. To evaluate the relative roles of various classes of processes in the burial of carbon on land, terrestrial...
Abnormal organic-matter maturation in the Yinggehai Basin, South China Sea: Implications for hydrocarbon expulsion and fluid migration from overpressured systems
F. Hao, S. Li, W. Dong, Z. Hu, B. Huang
1998, Journal of Petroleum Geology (21) 427-444
Three superimposed pressure systems are present in the Yinggehai Basin, South China Sea. A number of commercial, thermogenic gas accumulations have been found in an area in which shale diapirs occur. Because the reservoir intervals are shallow and very young, they must have filled with gas rapidly. The thick (up...
Tectonic Processes on Europa: Tidal Stresses, Mechanical Response, and Visible Features
R. Greenberg, P. Geissler, G. Hoppa, B.R. Tufts, D.D. Durda, R. Pappalardo, J.W. Head, R. Greeley, R. Sullivan, M. H. Carr
1998, Icarus (135) 64-78
Europa's orbital eccentricity, driven by the resonance with Io and Ganymede, results in "diurnal" tides (3.5-day period) and possibly in nonsynchronous rotation. Both diurnal variation and nonsynchronous rotation can create significant stress fields on Europa's surface, and both effects may produce cracking. Patterns and time sequences of apparent tectonic features...
Mercury in lake sediments of the Precambrian Shield near Huntsville, Ontario, Canada
P.E. Rasmussen, D.J. Villard, J.A.C. Fortescue, H.D. Gardner, S.L. Schiff, W.W. Shilts
1998, Environmental Geology (33) 170-182
Long sediment cores (> 1 m) were collected from eight Precambrian Shield lakes in southern Ontario, Canada and analyzed for mercury (Hg), loss-on-ignition (LOI), and a suite of 36 other elements. Results indicated at least 100-fold variation in sediment Hg concentrations between lakes in close proximity (from 450 ppb), comparable...
Aeromagnetic evidence for a volcanic caldera(?) complex beneath the divide of the West Antarctic Ice Sheet
John C. Behrendt, C. A. Finn, D. Blankenship, R.E. Bell
1998, Geophysical Research Letters (25) 4385-4388
A 1995–96 aeromagnetic survey over part of the Sinuous Ridge (SR) beneath the West Antarctic Ice Sheet (WAIS) divide shows a 70-km diameter circular pattern of 400–1200-nT anomalies suggesting one of the largest volcanic caldera(?) complexes on earth. Radar-ice-sounding (RIS) shows the northern part of this...
Large-area mapping of biodiversity
J. M. Scott, M.D. Jennings
1998, Conference Paper, Annals of the Missouri Botanical Garden
The age of discovery, description, and classification of biodiversity is entering a new phase. In responding to the conservation imperative, we can now supplement the essential work of systematics with spatially explicit information on species and assemblages of species. This is possible because of recent conceptual, technical, and organizational progress...
Field and laboratory evidence for intrinsic biodegradation of vinyl chloride contamination in a Fe(III)-reducing aquifer
P. M. Bradley, F. H. Chapelle, J.T. Wilson
1998, Journal of Contaminant Hydrology (31) 111-127
Intrinsic bioremediation of chlorinated ethenes in anaerobic aquifers previously has not been considered feasible, due, in large part, to 1) the production of vinyl chloride during microbial reductive dechlorination of higher chlorinated contaminants and 2) the apparent poor biodegradability of vinyl chloride under anaerobic conditions. In this study, a combination...
A decision support model to assess vulnerability to salt water intrusion in the great bend prairie aquifer of Kansas
M. Sophocleous, T. Ma
1998, Groundwater (36) 476-483
A relatively simple ground water decision support system (DSS) was developed to assist in identifying salt-water vulnerable areas and in developing management policies to prevent salt-water intrusion in central Kansas. The DSS is based on a combination of numerical modeling sensitivity analyses, multiple regression analyses,...
Potentially hazardous elements in coal: Modes of occurrence and summary of concentration data for coal components
Allan Kolker, Robert B. Finkelman
1998, Coal Preparation (19) 133-157
Mode-of-occurrence data are summarized for 13 potentially hazardous elements (Be, Cr, Mn, Co, Ni, As, Se, Cd, Sb, Hg, Pb, Th, U) in coal. Recent work has refined mode-of-occurrence data for Ni, Cr, and As, as compared to previous summaries. For Cr, dominant modes of occurrence include the clay mineral...
In situ FTIR and flash pyrolysis/GC-MS characterization of Protosalvinia (Upper Devonian, Kentucky, USA): Implications for maceral classification
Maria Mastalerz, J.C. Hower, A. Carmo
1998, Organic Geochemistry (28) 57-66
Protosalvinia from Devonian rocks in Kentucky has been analyzed using petrographic and in situ FTIR and flash pyrolysis/GC-MS techniques in order to discuss its origin and placement in organic matter classification. In reflected light, Protosalvinia resembles cutinite in shape, color and reflectance, whereas in fluorescent mode it reveals yellow-green fluorescence,...
Nonlethal evaluation of the physiological health of unionid mussels: Method for biopsy and glycogen analysis
T.J. Naimo, E.D. Damschen, R.G. Rada, E.M. Monroe
1998, Journal of the North American Benthological Society (17) 121-128
In long-lived unionid mussels, many short-term measures of growth are of limited value. Changes in physiological condition may be an early indication of stress, because the increased energy demand associated with stress often results in a depletion of glycogen reserves, the principal...
Multi-level slug tests in highly permeable formations: 1. Modification of the Springer-Gelhar (SG) model
V.A. Zlotnik, V. L. McGuire
1998, Journal of Hydrology (204) 271-282
A multi-level slug test model and a method for the evaluation of vertical profiles of hydraulic conductivity in highly permeable formations are developed. A double-packer system is employed to estimate local hydraulic conductivity. Depending on the formation and double-packer system parameters, the water level recovery in the tested well can...
Ice sheet history from Antarctic Continental Margin sediments: The ANTOSTRAT approach
P.F. Barker, P. J. Barrett, Angelo Camerlenghi, Alan K. Cooper, F.J. Davey, E.W. Domack, C. Escutia, Y. Kristoffersen, P. E. O’Brien
1998, Terra Antarctica (5) 737-760
The Antarctic Ice Sheet is today an important part of the global climate engine, and probably has been so for most of its long existence. However, the details of its history are poorly known, despite the measurement and use, over two decades, of low-latitude proxies of ice sheet volume. An...
Seasonal and interannual variations of atmospheric CO2 and climate
M. D. Dettinger, M. Ghil
1998, Tellus, Series B: Chemical and Physical Meteorology (50) 1-24
Interannual variations of atmospheric CO2 concentrations at Mauna Loa are almost masked by the seasonal cycle and a strong trend; at the South Pole, the seasonal cycle is small and is almost lost in the trend and interannual variations. Singular-spectrum analysis (SSA) is used here to isolate and reconstruct interannual signals...
Application of the top specified boundary layer (TSBL) approximation to initial characterization of an inland aquifer mineralization 1. Direct contact between fresh and saltwater
H. Rubin, R. W. Buddemeier
1998, Journal of Contaminant Hydrology (32) 353-376
This paper presents a basic study in generalized terms that originates from two needs: (1) to understand the major mechanisms involved in the mineralization of groundwater of the Great Bend Prairie aquifer of Kansas by saltwater originating from a deeper Permian bedrock formation, and (2) to develop simple, robust tools...
