Dietary requirements for essential branched-chain amino acids by lake trout
S. G. Hughes, G. L. Rumsey, M.C. Nesheim
1983, Transactions of the American Fisheries Society (112) 812-817
In a 12‐week growth study of the dietary requirements of young lake trout Salvelinus namaycush for essential branched‐chain amino acids, the leucine requirement was between 2.74 and 3.66%, and the isoleucine requirement between 1.54 and 2.06%, of dietary protein (as‐fed basis). These ranges are substantially lower than those published and...
The relationship of joints and stream drainage in flat-lying rocks of south-central New York and northern Pennsylvania
H. A. Pohn
1983, Zeitschrift fur Geomorphologie (27) 375-384
Examination of the relationship of joints to stream development shows that the oft-cited development of streams parallel to joint directions does not, in general, apply in south-central New York and adjacent northern Pennsylvania. Streams whose courses are oblique to the joint directions (joint-oblique valleys) tend to erode...
Measuring water surface and streambed elevation changes with the acoustic velocity metering system
Antonius Laenen
1983, Water Resources Research (19) 1317-1322
Acoustic velocity metering systems used to measure the water velocity along a diagonal path across a stream can also be used to measure stage and streambed changes. Underwater acoustic transmissions reflected from the water surface can accurately measure depth above transducers. Similarly, signals reflected from the streambed can indicate streambed...
New horizons for the national high-altitude photography program
Peter F. Bermel
1983, Pecora VIII Symposium 172-172
The National High-Altitude Photography Program (NHAP) is a multi-Federal agency activity to acquire uniform imagery for the establishment of a national high-altitude photographic data base. Federal agencies participating in NHAP have pooled their resources and consolidated photographic requirements in a systematic 6-year effort that will minimize duplication of photographic...
Lithologic mapping using Landsat thematic mapper data
M. H. Podwysocki, J.W. Salisbury, O. D. Jones, D.L. Mimms
1983, Pecora VIII Symposium 169-169
The Landsat-4 Thematic Mapper (TM), with its new near infrared bands centered at 1.65 μm and 2.20 μm and spatial resolution of 30 m has been used to distinguish rocks containing minerals having ferric-iron absorption bands in the visible and near-infrared and Al-O- and CO3 absorption bands in the 2.1-2.4...
Evaluation of thematic mapper data for natural resource assessment
R. H. Haas, F. A. Waltz
1983, Conference Paper, Pecora VIII Symposium
The U.S. Geological Survey EROS Data Center evaluated the utility of Landsat Thematic Mapper (TM) date for natural resource assessment, emphasizing manual interpretation and digital classification of the data for U.S. Department of the Interior applications. Substantially more information was derived from TM data than from Landsat Multispectral Scanner...
Thematic mapper: detailed radiometric and geometric characteristics
Hugh Kieffer
1983, Pecora VIII Symposium 75-75
Those radiometric characteristics of the Landsat 4 Thematic Mapper (TM) that can be established without absolute calibration of spectral data have been examined. Subscenes of radiometric all raw data (B-data) were examined on an individual detector basis: areas of uniform radiance were used to characterize subtle radiometric differences and...
U.S. Geological Survey land remote sensing activities
Doyle G. Frederick
1983, Pecora VIII Symposium 28-30
The U.S. Geological Survey (USGS) and the Department of the Interior (DOI) were among the earliest to recognize the potential applications of satellite land remote sensing for management of the country's land and water resources…not only as a user but also as a program participant responsible for final data processing,...
Feeding ecology of mallards wintering in Nebraska
Dennis G. Jorde, Gary L. Krapu, R.D. Crawford
1983, Journal of Wildlife Management (47) 1044-1053
Food use by mallards (Anas platyrhynchos) wintering on the Platte River in south central Nebraska was determined from mid-December to early March 1978-80. Mallards foraged in river channels, irrigation drainage canals, and agricultural areas. Plant matter formed 97% of the diet (dry weight) and diets did not vary between sexes...
Fish abundance and population stability in a reservoir tailwater and an unregulated headwater stream
K.E. Jacobs, W.D. Swink
1983, North American Journal of Fisheries Management (3) 395-402
Fish abundance and population stability were compared in the tailwater and in an unregulated tributary of Barren River Lake, a flood control reservoir in south central Kentucky. Fish abundance was greater in the tailwater near the dam and was dominated by three species common in the reservoir: gizzard shad (Dorosoma...
Some observations on the use of discriminant analysis in ecology
Byron K. Williams
1983, Ecology (64) 1283-1291
The application of discriminant analysis in ecological investigations is discussed. The appropriate statistical assumptions for discriminant are illustrated, and both classification and group separation approaches are outlined. Three assumptions that are crucial in ecological studies are discussed at length, and the consequences of their violation are developed. These assumptions are:...
Eruption-triggered avalanche, flood, and lahar at Mount St. Helens - Effects of winter snowpack
R. B. Waitt Jr., T.C. Pierson, N. S. MacLeod, R. J. Janda, B. Voight, R. T. Holcomb
1983, Science (221) 1394-1397
An explosive eruption of Mount St. Helens on 19 March 1982 had substantial impact beyond the vent because hot eruption products interacted with a thick snowpack. A blast of hot pumice, dome rocks, and gas dislodged crater-wall snow that avalanched through the crater and down the north flank. Snow in...
Seismic precursors to the Mount St. Helens eruptions in 1981 and 1982
S. D. Malone, C. Boyko, C.S. Weaver
1983, Science (221) 1376-1378
Six categories of seismic events are recognized on the seismograms from stations in the vicinity of Mount St. Helens. Two types of high-frequency earthquakes occur near the volcano and under the volcano at depths of more than 4 kilometers. Medium- and low-frequency earthquakes occur at shallow depths (less than 3...
Deformation monitoring at Mount St. Helens in 1981 and 1982
W.W. Chadwick Jr., D. A. Swanson, E.Y. Iwatsubo, C. C. Heliker, T.A. Leighley
1983, Science (221) 1378-1380
For several weeks before each eruption of Mount St. Helens in 1981 and 1982, viscous magma rising in the feeder conduit inflated the lava dome and shoved the crater floor laterally against the immobile crater walls, producing ground cracks and thrust faults. The rates of deformation accelerated before eruptions, and...
Predicting eruptions at Mount St. Helens, June 1980 through December 1982
D. A. Swanson, T. J. Casadevall, D. Dzurisin, S. D. Malone, C. G. Newhall, C.S. Weaver
1983, Science (221) 1369-1376
Thirteen eruptions of Mount St. Helens between June 1980 and December 1982 were predicted tens of minutes to, more generally, a few hours in advance. The last seven of these eruptions, starting with that of mid-April 1981, were predicted between 3 days and 3 weeks in advance. Precursory seismicity, deformation...
Deep earthquakes beneath Mount St. Helens: Evidence for magmatic gas transport?
C.S. Weaver, J.E. Zollweg, S. D. Malone
1983, Science (221) 1391-1394
Small-magnitude earthquakes began beneath Mount St. Helens 40 days before the eruption of 20 March 1982. Unlike earlier preeruption seismicity for this volcano, which had been limited to shallow events (less than 3 kilometers), many of these earthquakes were deep (between 5 and 11 kilometers). The location of these preeruptive...
Gas emissions and the eruptions of Mount St. Helens through 1982
T. Casadevall, W. Rose, T. Gerlach, L. P. Greenland, J. Ewert, R. Wunderman, R. Symonds
1983, Science (221) 1383-1385
The monitoring of gas emissions from Mount St. Helens includes daily airborne measurements of sulfur dioxide in the volcanic plume and monthly sampling of gases from crater fumaroles. The composition of the fumarolic gases has changed slightly since 1980: the water content increased from 90 to 98 percent, and the...
Eruption prediction aided by electronic tiltmeter data at Mount St. Helens
D. Dzurisin, J.A. Westphal, Daniel J. Johnson
1983, Science (221) 1381-1383
Telemetry from electronic tiltmeters in the crater at Mount St. Helens contributed to accurate predictions of all six effusive eruptions from June 1981 to August 1982. Tilting of the crater floor began several weeks before each eruption, accelerated sharply for several days, and then abruptly changed direction a few minutes...
Petrologic monitoring of 1981 and 1982 eruptive products from Mount St. Helens
K. V. Cashman, J. E. Taggart
1983, Science (221) 1385-1387
New material from the dacite lava dome of Mount St. Helens, collected soon after the start of each successive extrusion, is subjected to rapid chemical and petrologic analysis. The crystallinity of the dacite lava produced in 1981 and 1982 is 38 to 42 percent, about 10 percent higher than for...
Reproduction by the endangered cui-ui in the lower Truckee River
G.G. Scoppettone, Gary Wedemeyer, M. Coleman, H. Burge
1983, Transactions of the American Fisheries Society (112) 788-793
Adult spawning behavior and emigration of larvae of the endangered cui-ui Chasmistes cujus were studied in a natural side channel of the lower Truckee River. External radio-tags placed on eight apparently did not affect spawning behavior. Cui-uis spawned in clusters of two to seven fish; usually a single female was...
Results of an adaptive environmental assessment modeling workshop concerning potential impacts of drilling muds and cuttings on the marine environment
Gregor T. Auble, Austin K. Andrews, Richard A. Ellison, David B. Hamilton, Richard A. Johnson, James E. Roelle, David R. Marmorek
1983, Report
Drilling fluids or "muds" are essential components of modern drilling operations. They provide integrity for the well bore, a medium for removal of formation cuttings, and lubrication and cooling of the drill bit and pipe. The modeling workshop described in this report was conducted September 14-18, 1981 in Gulf Breeze,...
Opening of the Red Sea: Constraints from a palaeomagnetic study of the As Sarat volcanic field, south‐western Saudi Arabia
Karl S. Kellogg, R. L. Reynolds
1983, Geophysical Journal of the Royal Astronomical Society (74) 649-665
Four stratigraphic sections through alkali basalt flows of Oligocene to Miocene age (29‐24 Ma) in the As Sarat volcanic field, south‐western Saudi Arabia, were sampled for palaeomagnetic study. After systematic alternating‐field demagnetization, 42 magnetically acceptable flows (139 samples) yield a mean direction of magnetization of =355.3°, =15.2° (α=4.3°), which defines...
Vegetation characteristics important to common songbirds in east Texas
Richard N. Conner, James G. Dickson, Brian A. Locke, Charles A. Segelquist
1983, The Wilson Bulletin (95) 349-361
Multivariate studies of breeding bird communities have used principal component analysis (PCA) or several-group (three or more groups) discriminant function analysis (DFA) to ordinate bird species on vegetational continua (Cody 1968, James 1971, Whitmore 1975). In community studies, high resolution of habitat requirements for individual species is not always...
Bathyal ostracodes from the Florida-Hatteras slope, the Straits of Florida, and the Blake Plateau
Thomas M. Cronin
1983, Marine Micropaleontology (8) 89-119
Epibathyal ostracodes from the Florida-Hatteras slope, the Blake Plateau and the Straits of Florida were studied to determine the relationship of numerous genera and species to bottom-water environmental conditions such as dissolved oxygen and bottom-water temperatures. From a total of 100 samples, 44 samples evenly distributed between 200 and 1100...
Feminization of channel catfish by oral administration of steroid sex hormones
C. A. Goudie, B.D. Redner, B.A. Simco, K. B. Davis
1983, Transactions of the American Fisheries Society (112) 670-672
Oral administration of 17‐β‐estradiol or 17‐α‐ethynyltestosterone to sexually undifferentiated channel catfish Ictaturus punctatus during the first 21 days after yolk‐sac absorption resulted in the production of 100% females. The androgen was effective at doses of 6 to 600 μg/g of feed, but not at 0.6 μg/g....
