Creating a standardized watersheds database for the Lower Rio Grande/Río Bravo, Texas
J.R. Brown, Randy L. Ulery, Jean W. Parcher
2000, Open-File Report 00-065
This report describes the creation of a large-scale watershed database for the lower Rio Grande/Río Bravo Basin in Texas. The watershed database includes watersheds delineated to all 1:24,000-scale mapped stream confluences and other hydrologically significant points, selected watershed characteristics, and hydrologic derivative datasets.<span size="3" data-mce-style="font-size:...
Nutrient pollution of coastal rivers, bays, and seas
Robert W. Howarth, D. B. Anderson, James E. Cloern, Chris Elfring, Charles S. Hopkinson, Brian Lapointe, Tom Malone, Nancy Marcus, Karen McGlathery, Andrew N. Sharpley, Dan Walker
2000, Issues in Ecology 1-16
Over the past 40 years, antipollution laws have greatly reduced discharges of toxic substances into our coastal waters. This effort, however, has focused largely on point-source pollution of industrial and municipal effluent. No comparable effort has been made to restrict the input of nitrogen (N)...
Effects of food limitation and emigration on self-thinning in experimental minnow cohorts
J. B. Dunham, B. R. Dickerson, E. Beever, R. D. Duncan, G.L. Vinyard
2000, Journal of Animal Ecology (69) 927-934
1. The theory of food-regulated self-thinning (FST) for mobile animals predicts population density (N) to be an inverse function of mean body mass (W) scaled to an exponent (b), such that N = k W−b, where k is a constant. FST also predicts energy requirements (or energy flow) to remain constant over time (termed energetic...
Modeling the hydroclimatology of the San Francisco Bay-Delta estuary and watershed
Noah Knowles
2000, Thesis
No abstract available....
Abiotic and biotic controls of spatial pattern at alpine treeline
George P. Malanson, Ningchuan Xiao, K.J. Alftine, Mathew Bekker, David R. Butler, Daniel G. Brown, David M. Cairns, Daniel Fagre, Stephen J. Walsh
2000, Conference Paper, 4th International Conference on Integrating GIS and Environmental Modeling (GIS/EM4): Problems, Prospects and Research Needs
At alpine treeline, trees and krummholz forms affect the environment in ways that increase their growth and reproduction. We assess the way in which these positive feedbacks combine in spatial patterns to alter the environment in the neighborhood of existing plants. The research is significant because areas of alpine tundra...
A paleolatitude approach to assessing surface temperature history for use in burial heating models
Charles E. Barker
2000, International Journal of Coal Geology (43) 121-135
Calculations using heat flow theory as well as case histories show that over geologic time scales (106 years), changes in mean annual surface temperature (Ts) on the order of 10°C penetrate kilometers deep into the crust. Thus, burial heating models of sedimentary basins, which typically span kilometers in depth and...
Physical modeling of a prototype slim-hold time-domain dielectric logging tool
J.D. Abraham
M. H. Powers, editor(s)
2000, Conference Paper, Proceedings of the symposium on the Application of geophysics to engineering and environmental problems
Influence of El Niño–Southern Oscillation (ENSO) events on the evolution of central California's shoreline
Curt D. Storlazzi, Gary B. Griggs
2000, Geological Society of America Bulletin (112) 236-249
Significant sea-cliff erosion and storm damage occurred along the central coast of California during the 1982–1983 and 1997–1998 El Niño winters. This generated interest among scientists and land-use planners in how historic El Niño–Southern Oscillation (ENSO) winters have affected the coastal climate of central California. A relative ENSO intensity index...
Strategic science plan Salton Sea restoration project
Salton Sea Science Subcommittee
2000, Report
The Salton Sea is an ecosystem in peril. Its prehistory consists of a series of intermittent lakes dependent on infrequent flooding of the Colorado River, while the modern Salton Sea originated from the desire to harness the flow of the Colorado River for irrigation. What began as an accident of...
Frequency dependent Lg attenuation in south-central Alaska
D.E. McNamara
2000, Geophysical Research Letters (27) 3949-3952
The characteristics of seismic energy attenuation are determined using high frequency Lg waves from 27 crustal earthquakes, in south-central Alaska. Lg time-domain amplitudes are measured in five pass-bands and inverted to determine a frequency-dependent quality factor, Q(f), model for south-central Alaska. The inversion in this study yields the frequency-dependent quality...
Accuracy assessment for the U.S. Geological Survey Regional Land-Cover Mapping Program: New York and New Jersey Region
Zhi-Liang Zhu, Limin Yang, Stephen V. Stehman, Raymond L. Czaplewski
2000, Photogrammetric Engineering and Remote Sensing (66) 1425-1438
The U.S. Geological Survey, in cooperation with other government and private organizations, is producing a conterminous U.S. land-cover map using Landsat Thematic Mapper 30-meter data for the Federal regions designated by the U.S. Environmental Protection Agency. Accuracy assessment is to be conducted for each Federal region to estimate overall and...
Estimating forest crown area removed by selection cutting: a linked regression-GIS approach based on stump diameters
S.C. Anderson, J.A. Kupfer, R.R. Wilson, R.J. Cooper
2000, Forest Ecology and Management (137) 171-177
The purpose of this research was to develop a model that could be used to provide a spatial representation of uneven-aged silvicultural treatments on forest crown area. We began by developing species-specific linear regression equations relating tree DBH to crown area for eight bottomland tree species at White River National...
Evaluating immunocontraception for managing suburban white-tailed deer in Irondequoit, New York
B.A. Rudolph, W.F. Porter, H.B. Underwood
2000, Journal of Wildlife Management (64) 463-473
Immunocontraception is frequently proposed as an alternative to lethal removal of females for deer management. However, little information is available for evaluating the potential of applying immunocontraceptives to free-ranging populations. Our objectives were to estimate effort required to apply porcine zona pellucida (PZP) to individual deer and assess the utility...
Estimation of contributions to population growth: A reverse-time capture-recapture approach
J.D. Nichols, J.E. Hines, J.D. Lebreton, R. Pradel
2000, Ecology (81) 3362-3376
We consider methods for estimating the relative contributions of different demographic components, and their associated vital rates, to population growth. We identify components of the population at time i (including a component for animals not in the population at i). For each such component we ask the following question: “What is the probability...
Inferences about nested subsets structure when not all species are detected
E. Cam, J.D. Nichols, J.E. Hines, J.R. Sauer
2000, Oikos (91) 428-434
Comparisons of species composition among ecological communities of different size have often provided evidence that the species in communities with lower species richness form nested subsets of the species in larger communities. In the vast majority of studies, the question of nested subsets has been addressed using information on...
Regional effects of hydrologic alterations on riverine macrobiota in the New World: Tropical-temperate comparisons
C. M. Pringle, Mary C. Freeman, B. J. Freeman
2000, BioScience (50) 807-823
This article has two main objectives: to examine what is known about regional effects of hydrologic modifications in temperate and tropical areas of the New World (i.e., North and South America and the Caribbean), with an emphasis on fishes and molluscs; and to discuss research needs regarding regional effects...
Stratification based on reproductive state reveals contrasting patterns of age-related variation in demographic parameters in the kittiwake
E. Cam, J. #NAME? Monnat
2000, Oikos (90) 560-574
Heterogeneity in individual quality can be a major obstacle when interpreting age-specific variation in life-history traits. Heterogeneity is likely to lead to within-generation selection, and patterns observed at the population level may result from the combination of hidden patterns specific to subpopulations. Population-level patterns are not relevant to...
Influence of inner-continental shelf geologic framework on the evolution and behavior of the barrier-island system between Fire Island Inlet and Shinnecock Inlet, Long Island, New York
W. C. Schwab, E.R. Thieler, J.R. Allen, D.S. Foster, B.A. Swift, J. F. Denny
2000, Journal of Coastal Research (16) 408-422
High-resolution, sea-floor mapping techniques, including sidescan-sonar and subbottom profiling, were used to investigate how the geologic framework of the inner-continental shelf influenced the Holocene evolution and modern behavior of the Fire Island barrier-island system, Long Island, New York. The inner-continental shelf off Long Island is divided into two physiographic...
Relation of waterfowl poisoning to sediment lead concentrations in the Coeur d'Alene River Basin
W. N. Beyer, D. J. Audet, G. H. Heinz, D. J. Hoffman, D. Day
2000, Ecotoxicology (9) 207-218
For many years, waterfowl have been poisoned by lead after ingesting contaminated sediment in the Coeur d'Alene River Basin, in Idaho. Results of studies on waterfowl experimentally fed this sediment were combined with results from field studies conducted in the Basin to relate sediment lead concentration to injury to waterfowl....
Relative species richness and community completeness: avian communities and urbanization in the mid-Atlantic states
E. Cam, J.D. Nichols, J.R. Sauer, J.E. Hines, C.H. Flather
2000, Ecological Applications (10) 1196-1210
The idea that local factors govern local richness has been dominant for years, but recent theoretical and empirical studies have stressed the influence of regional factors on local richness. Fewer species at a site could reflect not only the influence of local factors, but also a smaller regional pool....
Capturing American black ducks in tidal waters
M.K. Harrison Sr., G.M. Haramis, Dennis G. Jorde, Daniel B. Stotts
2000, Journal of Field Ornithology (71) 153-158
We modified conventional, funnel-entrance dabbling duck bait traps to increase captures for banding of American Black Ducks (Anas rubripes) in tidal saltmarsh habitats of Smith Island, Maryland, one of the few remaining strongholds for breeding Black Ducks in the Chesapeake Bay. Traps and trapping techniques were adapted to tidal...
Toxicity of manganese to Ceriodaphnia dubia and Hyalella azteca
P. J. Lasier, P. V. Winger, K. J. Bogenrieder
2000, Archives of Environmental Contamination and Toxicology (38) 298-304
Manganese is a toxic element frequently overlooked when assessing toxicity of effluents, sediments, and pore waters. Manganese can be present at toxic levels in anoxic solutions due to increased solubility under chemically reducing conditions, and it can remain at those levels for days in aerated test waters due to slow...
A radio transmitter attachment technique for soras
G. Michael Haramis, Gregory D. Kearns
2000, Journal of Field Ornithology (71) 135-139
We modified a figure-8 leg-loop harness designed for small passerines to attach successfully 1.8-g radio transmitters over the synsacrum of migrant Soras (Porzana carolina). Because of the short caudal region of Soras, addition of a waist loop was critical to securing the transmitter while leg loops were maintained to center...
A double-observer approach for estimating detection probability and abundance from point counts
J.D. Nichols, J.E. Hines, J.R. Sauer, F.W. Fallon, J.E. Fallon, P.J. Heglund
2000, The Auk (117) 393-408
Although point counts are frequently used in ornithological studies, basic assumptions about detection probabilities often are untested. We apply a double-observer approach developed to estimate detection probabilities for aerial surveys (Cook and Jacobson 1979) to avian point counts. At each point count, a designated 'primary' observer indicates to...
Contaminant exposure and effects: Terrestrial vertebrates database: Trends and data gaps for Atlantic Coast estuaries
Barnett A. Rattner, J.L. Pearson, N. H. Golden, J.B. Cohen, R.M. Erwin, M. A. Ottinger
2000, Environmental Monitoring and Assessment (63) 131-142
In order to examine the condition of biota in Atlantic coast estuaries, "Contaminant Exposure and Effects—Terrestrial Vertebrates" database (CEE-TV) has been compiled through computerized search of published literature, review of existing databases, and solicitation of unpublished reports from conservation agencies, private groups, and universities. Summary information has been entered into...
