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Articles 10081 - 10110 of 10265
Full-Text Articles in Physical Sciences and Mathematics
The Prairie Naturalist Volume 4, Nos. 3 And 4. September–December 1972
The Prairie Naturalist Volume 4, Nos. 3 And 4. September–December 1972
The Prairie Naturalist
THE SANDHILL CRANE WITH EMPHASIS ON ASPECTS
RELATED TO NORTH DAKOTA ▪ Douglas H. Johnson and Robert E. Stewart
SIZE AND COLORATION CHARACTERISTICS OF NEOTENIC SALAMANDERS IN DEVILS LAKE, N. D. ▪ Douglas W. Larson
BIRDS' EGGS: AN AID TO NATURE APPRECIATION ▪ S. O. Kolstoe
BIRD MORTALITY AT FOUR TOWERS IN EASTERN NORTH DAKOTA — FALL 1972 ▪ Michael Avery and Tom Clement
POPULATION IRRUPTION OF THE LEAST WEASEL (Mustela nivalis) IN EAST CENTRAL NORTH DAKOTA ▪ John T. Lokemoen and Kenneth F. Higgins
Groundwater - Surface Water Integration Study In The Grand Prairie Of Arkansas, Carl L. Griffis
Groundwater - Surface Water Integration Study In The Grand Prairie Of Arkansas, Carl L. Griffis
Technical Reports
A mathematical model of the Quaternary Aquifer of the Grand Prairie, Arkansas was developed and used to evaluate a variety of methods of artificially recharging this aquifer. In addition, the model was used to evaluate the impact of various levels of water management and the probable movement of artificially recharged water in the aquifer. Improved water management and the use of recharge wells were the two alternatives that showed the most promise as potential solutions. The rate of movement of recharged water was determined by the model to be 300 ft./year under a gradient of 16 ft./mile.
Phytoplankton Successions And Lake Dynamics In Las Vegas Bay, Lake Mead, Nevada, Ervon R. Koening, Richard W. Tew, James E. Deacon
Phytoplankton Successions And Lake Dynamics In Las Vegas Bay, Lake Mead, Nevada, Ervon R. Koening, Richard W. Tew, James E. Deacon
Publications (WR)
Phytoplankton successions, applications of the general growth equation, and physical measurements have been employed to investigate events occurring at the interface between industrial and sewage effluent contained in Las Vegas Wash and the waters of Lake Mead, Nevada. The data indicate that the entering waters tend to form a density current interrupted at intervals by dynamic effects generated in the lake. The dynamic relationships described here for the spring months suggest that a much more thorough understanding of physical, chemical and biological interactions is necessary to permit solution of the numerous problems of Las Vegas Bay discussed or alluded to …
The Prairie Naturalist Volume 4, No. 2. June 1972
The Prairie Naturalist Volume 4, No. 2. June 1972
The Prairie Naturalist
EDITORIAL: Coordination: A Step for Environmental Protection ▪ Paul B. Kannowski
AN ANALYSIS OF BARN OWL AND GREAT HORNED OWL PELLETS FROM WESTERN NEBRASKA ▪ Eric A. Rickart
SUMMER OBSERVATIONS OF THE SHORT-EARED OWL IN THE RED RIVER VALLEY ▪ W. J. Walley
ADDITIONAL GLAUCOUS GULL RECORD FOR NORTH DAKOTA ▪ B. J. Rose
MIGRATION OF BIRDS IN NORTH DAKOTA DURING FALL 1971 ▪ Douglas H. Johnson, John T. Lokemoen and Paul F. Springer
WIDGEONGRASS BALLS ON ALKALI LAKES ▪ George A. Swanson and Paul F. Springer
A PROBABLE INSTANCE OF SONGBIRD COLLISION MORTALITY ▪ R. Wayne Weier
MUNICIPAL FLOODPLAIN …
The Delaware Limestone (Middle Devonian) Of Southwestern Ontario, Canada, Robert F. Diffendal Jr.
The Delaware Limestone (Middle Devonian) Of Southwestern Ontario, Canada, Robert F. Diffendal Jr.
School of Natural Resources: Faculty Publications
The Delaware Limestone of southwestern Ontario was originally called a part of the Corniferous Limestone by Murray (184.3-53). Since that time the same outcroppings have been designated, either wholly or partially, as the Onondaga Formation, the Big Lime, Delaware Limestone, Norfolk Formation, Dundee Limestone, Columbus Limestone, and the Dundee (= Delaware) Limestone. As recently as 1971 the names Dundee Limestone and Delaware Limestone were used for the same formation.
Hand specimen and petrographic study of samples from nineteen localities in southwestern Ontario indicates that the limestones of the formation exposed on the Niagara peninsula are intermediate in type between the …
Saltmarsh Ecology And Resource Protection, Gerard Desire Blais Jr.
Saltmarsh Ecology And Resource Protection, Gerard Desire Blais Jr.
Marine Affairs Theses and Major Papers
A panoramic lack of conservation education has produced a populace largely unaware of the value of marshland resources or measures for their protection. In a relentless era of ecological abuse, wetlands and salt marshes rank with endangered animal species in the quantitative loss culminating in extinction. Challenged continually by the relentless sea and exploited by unsound attempts at development, management, or even conservation, the efficiency of the marshlands is decreasing with each successive invasion. There is a demonstrated reduction in biological productivity, flood control, and water quality in areas where dredging, draining, and filling of marshes has taken place.
Digital Video Display System Using Cathode-Ray Tube, George M. Low, Arthur I. Zygielbaum, Warren L. Martin, Alexander Engel
Digital Video Display System Using Cathode-Ray Tube, George M. Low, Arthur I. Zygielbaum, Warren L. Martin, Alexander Engel
School of Natural Resources: Faculty Publications
A digital video display system (DWDS) is disclosed for display of image, alphanumeric and other data on a cathode-ray tube (CRT) with sequential raster scan and two, four or eight gray shades. The DVDS includes a central processing unit for ac tivating the system, selecting the X (horizontal axis) and Z (in tensity modulation) modes, and designating the starting loca tion of two successive rasters of data from a memory accessed by a data multiplexer subsystem (DMS). At the end of each raster, the DMS interrupts the computer for a new starting lo cation of a raster of data to …
Communications Link For Computers, Thomas O. Paine, Arthur I. Zygielbaum, James W. Layland, Warren L. Martin
Communications Link For Computers, Thomas O. Paine, Arthur I. Zygielbaum, James W. Layland, Warren L. Martin
School of Natural Resources: Faculty Publications
A system is disclosed for a computer to communicate with a selected one of a plurality of other computers through two identical communications links associated with the communicating computers. A single channel connects the two links which operate at a clock rate independent of the computers. Binary digits and clock pulses are combined and converted into a three-level signal for serial transmission over the single channel. Both control messages and data words may be transmitted. Each message and word transmitted is checked for error by the receiving link before it is accepted and the receiving computer is interrupted. If error …
The Prairie Naturalist Vol. 4, No.1. March, 1972
The Prairie Naturalist Vol. 4, No.1. March, 1972
The Prairie Naturalist
EDITORIAL: Advertising by Power Suppliers ▪ William A. Buresh
FIRST FLOWERS OF TREES, SHRUBS AND VINES IN THE FARGO, NORTH DAKOTA AREA ▪ O. A. Stevens
CHRISTMAS BIRD COUNTS FOR NORTH DAKOTA—1971 ▪ Robert N. Randall
ENVIRONMENTAL LEGISLATION IN NORTH DAKOTA—EXPECTATIONS AND REALITIES ▪ Paul B. Kannowski
SEASONAL NOTES ON PLANKTON ALGAE OF EAST STUMP LAKE, NORTH DAKOTA ▪ Dean W. Blinn
A SKUNK WITH A GLASS COLLAR ▪ Peter W. Rakowski
SPRING MIGRATION OF BIRDS IN NORTH DAKOTA IN 1971 ▪ Paul F. Springer, Douglas H. Johnson and John T. Lokemoen
NOTE
Red throated loon observed on Lake Ashtabula, …
Simultaneous Determination Of Short-Period Photosynthesis And Evapotranspiration (Horticulture And Forestry Progress Report No. 91), Norman J. Rosenberg
Simultaneous Determination Of Short-Period Photosynthesis And Evapotranspiration (Horticulture And Forestry Progress Report No. 91), Norman J. Rosenberg
School of Natural Resources: Faculty Publications
No abstract provided.
Pheasant Production Using Wild Cocks And Penned Game-Farm Hens, Michael R. Grode
Pheasant Production Using Wild Cocks And Penned Game-Farm Hens, Michael R. Grode
Electronic Theses and Dissertations
Pheasant production using free-flying wild cooks and penned game-farm hens was evaluated during 1971. Hens were placed in 0.5-acre pens to compare production at density levels of 10, 20, and 40 hens per acre. Wild cooks entered the 0.5-acre pens the day following introduction of the game-farm hens. The greatest numbers of cooks were observed in the pens with the highest density of hens. Censusing in mid-March indicated a population of 12 to 15 wild cooks in the vicinity of the study pens. A known mortality of 31 hens occurred and percentage mortality was similar at each density level. Pulling …
Influence Of Weather On Movement And Habitat Use Of Hen Pheasants During Brood Rearing, James M. Ruth
Influence Of Weather On Movement And Habitat Use Of Hen Pheasants During Brood Rearing, James M. Ruth
Electronic Theses and Dissertations
Pheasants survive in a wide range of yearly weather extremes but can be limited by certain short-term weather factors (Graham and Hosterburg 1948). Study of short-term weather conditions can therefore be important in understanding pheasant survival. Many studies have been done on yearly and seasonal effects of weather on pheasant production and survival. Bemitt and Terril (1940) reported on possible temperature factors in pheasant management in the north central area of the United States. Effects of weather on pheasant reproduction were studied by Buss and Swanson (1950) and Kozieky et al. (1955). MacKullan and Eherhardt (1953) studied the tolerance of …
Reports Of 1971 Progress Volume 3 Terrestrial Validation Studies Part Ii. Individual Sites, U.S. International Biological Program
Reports Of 1971 Progress Volume 3 Terrestrial Validation Studies Part Ii. Individual Sites, U.S. International Biological Program
Progress reports
No abstract provided.
Reports Of 1971 Progress Volume 1 Central Studies, U.S. International Biological Program
Reports Of 1971 Progress Volume 1 Central Studies, U.S. International Biological Program
Progress reports
No abstract provided.
Reports Of 1971 Progress Volume 5 Aquatic Studies, U.S. International Biological Program
Reports Of 1971 Progress Volume 5 Aquatic Studies, U.S. International Biological Program
Progress reports
No abstract provided.
Abstract Of 1971 Progress Report, U.S. International Biological Program
Abstract Of 1971 Progress Report, U.S. International Biological Program
Progress reports
No abstract provided.
Reports Of 1971 Progress Volume 4 Terrestrial Process Studies, U.S. International Biological Program
Reports Of 1971 Progress Volume 4 Terrestrial Process Studies, U.S. International Biological Program
Progress reports
No abstract provided.
Assimilation, Metabolism And Growth Of Utah Chub, Gila Atraria, F.C. Cheng, R.L. Wallace, T.C. Bjornn, C. Macphee
Assimilation, Metabolism And Growth Of Utah Chub, Gila Atraria, F.C. Cheng, R.L. Wallace, T.C. Bjornn, C. Macphee
Progress reports
No abstract provided.
Reports Of 1971 Progress Volume 2 Terrestrial Validation Studies Part I. Methodological, U.S. International Biological Program
Reports Of 1971 Progress Volume 2 Terrestrial Validation Studies Part I. Methodological, U.S. International Biological Program
Progress reports
No abstract provided.
Environment And Communiy Organization In Grasslands Of Canyonlands National Park, Edgar F. Kleiner, K. T. Harper
Environment And Communiy Organization In Grasslands Of Canyonlands National Park, Edgar F. Kleiner, K. T. Harper
Canyonlands Research Bibliography
Sixty uniformly distributed stands in adjacent areas, 40 in Virginia Park (virgin) and 20 in Chesler Park (grazed), were analyzed. Cryptogamic and vascular species were recorded; cover was analyzed by the point sampling method, and frequency by means of 25 quadrats (each 0.125 m^2) per stand. The prevalent species (26 in Virginia, 23 in Chesler) were selected on the basis of a constancy-times-frequency index. Interspecific association patterns were determined by means of simple procedures based on quadrat frequency values for each species in the individual stands. Major environmental variables were recorded at each stand, and soil samples from four depths …
Water Resources Of Part Of Canyonlands National Park, Southeastern Utah, C. T. Sumsion, E. L. Bolke
Water Resources Of Part Of Canyonlands National Park, Southeastern Utah, C. T. Sumsion, E. L. Bolke
Canyonlands Research Bibliography
Canyonlands National Park is in about the center of the Canyon Lands section of the Colorado Plateaus physiographic province in southeastern Utah. The part of the park discussed embraces an area of about 400 square miles comprising isolated mesas, precipitous canyons, and dissected broad benches near the confluence of the Green and Colorado Rivers, the only perennial streams in the area. The climate is arid to semiarid; normal annual precipitation ranges from less than 8 to about 10 inches. Potential evapotranspiration is about 41 inches annually.
Geology of the park is characterized by nearly horizontal strata that dip gently northward. …
The Colorado Plateau, Robert Durrenberger
The Colorado Plateau, Robert Durrenberger
Canyonlands Research Bibliography
The Colorado Plateau was one of the last areas in the United States to be developed economically. Before the 1880s it was virtually empty except for Indians. Today the vast scenic and energy resources of the area are under development, and projections for future development are frightening. Problems of land use management are directly related to the fragmented nature of landholdings. Present methods of consolidation are inadequate, and new approaches to the organization of space must be devised if further degradation of the environment is to be prevented.
Development Of Techniques For Distribution Of Baits To Raccoon For Chemosterilant Studies, Richard L. Nelson
Development Of Techniques For Distribution Of Baits To Raccoon For Chemosterilant Studies, Richard L. Nelson
Electronic Theses and Dissertations
Sudan Red IV, Sudan Black B, and demethylchlortetracycline (DMCT) were tested as physiological markers in baits for raccoon (Procyon lotor). DMCT was readily detected in the jawbone of raccoons given 50 mg when examined under an ultraviolet light at period of 7, 30, 75, and 450 days following treatment. Seven days after administering 75 mg of Sudan Red IV, it could not be detected in fat deposits. Sudan Black B, administered in similar dosage, could not be detected at 30 days. A total of 1826 chicken eggs containing 50 mg DMCT was distributed on a 25 square-mile study area between …
Effects Of Diethylstilbestrol On Reproduction In The Black-Tailed Prairie Dog, Donald G. Pfeiffer
Effects Of Diethylstilbestrol On Reproduction In The Black-Tailed Prairie Dog, Donald G. Pfeiffer
Electronic Theses and Dissertations
Research was conducted in southwestern South Dakota in 1970 and 1971 to obtain information on the reproductive cycle of the black-tailed prairie dog (Cynomys ludovicianus) and to test effectiveness of diethylstilbestrol as a reproductive inhibitor. Embryo body lengths from 10 pregnant females were compared to body lengths of 14 known day-old young to learn the peak breeding period when an estrogenic chemosterilant would be most effective. Conception dates were obtained for three females by backdating the gestation period. The breeding peak was found to occur in late February and early March in South Dakota. Nine of 11 Prairie dogs were …
Food Selectivity Of The Black Bullhead (Ictalurus Melas, Rafinesque) In Lake Poinsett, South Dakota, Andrew J. Repsys
Food Selectivity Of The Black Bullhead (Ictalurus Melas, Rafinesque) In Lake Poinsett, South Dakota, Andrew J. Repsys
Electronic Theses and Dissertations
The food habits of young-of-the-year, subadult and adult black bullheads were studied in Lake Poinsett, South Dakota, from March, 1970, to April, 1971. Two hundred twenty young-of-the-year (37-87 mm total length) fed primarily on limnetic cladocerans and copepods. Leptodora and Diaphanosoma comprised 86.5% of the total food volume. Chironomid larvae and pupae made up 5.6% of the total. Other benthic organisms and littoral cladocerans together contributed less than 1%. Stomach contents of 608 subadult and adult black bullhead (143-304 mm total length) indicated significant seasonal vairaiton in diet. Daphnia pulex and chronomid larvae were important food items in winter. Bullheads …
Food Habits Of Fish In A Multispecies Farm Pond, Thomas W. Gengerke
Food Habits Of Fish In A Multispecies Farm Pond, Thomas W. Gengerke
Electronic Theses and Dissertations
Food habits of yellow perch, bluegill, and black crappie were studied during 1970 and 1971 in Abbey Pond, South Dakota. Aquatic insects, zooplankton, mollusks, and fish were the most frequently consumed food items by the three species. Yellow perch led primarily on aquatic insects, zooplankton, and mollusks. Aquatic insects were dominant (by volume) in 40.0 and 61.5 percent of the samples respectively for the two years. Zooplankton, mollusks, aquatic insects, and bryozoans were the dominant food items by volume of adult bluegills. On an annual basis aquatic insects were the most important food item in the diet. Adult black crappies …
Waterfowl Production In The James River Valley Of South Dakota, William E. Wheeler
Waterfowl Production In The James River Valley Of South Dakota, William E. Wheeler
Electronic Theses and Dissertations
A study of waterfowl production was conducted on two study areas in the James River Valley of South Dakota in 1971 and 1972. Its objectives were to measure rates of reproductive success and to determine the effect of land use and other influences on duck production. The five most abundant species of nesting ducks were blue-winged teal (Anas discors), mallard (platyrhvnchos), gadwall (A. strepera), shoveler (clypeata), and pintail (acuta). Seventy-two percent of the wetland habitat on the study areas consisted of temporary (Type l and Type 3) water areas. Only 3.9 percent of the wetlands represented semi-permanent (Type 4) and …
Effects Of Polychlorinated Biphhenyls In The Ring-Necked Pheasant, Robert Bernard Dahlgren
Effects Of Polychlorinated Biphhenyls In The Ring-Necked Pheasant, Robert Bernard Dahlgren
Electronic Theses and Dissertations
In 1970 and 1971, cock pheasants (Phasianus colchicus) were given single capsules weekly containing 0 and 25 mg polychlorinated biphenyls (PCB), Aroclor 1254, and hens were given O, 12.5, and 50 mg. Egg production was reduced (P<0.01) in the hens given 50 mg PCB both years. Fertility, determined by visual inspection of incubated eggs, was unaffected by PCB. Hatchability was lowest in the group of hens given 50 mg in both years but significantly lower (P<0.01) only in 1971. PCB adversely affected the viability of the embryo both years, as the number of eggs pipped but not hatched in PCB groups was higher (P<0.05). PCB did not affect eggshell thickness. Behavior on the visual cliff shortly after hatching was affected among offspring of hens given 50 mg PCB in 1970 (P,0.01). Offspring of hens given 50 mg chose the visually-deep side of the cliff. No differences in behavior on the visual cliff were evident in 1971. Response to hand catching of offspring was affected in 1970 (P <0.01). The ability of penned pheasants to avoid hand capture was least where both parents received PCB, followed by those where hens only, cocks only and neither parent received PCB. No differences in response to hand capture among groups were found in 1971. Weights of chicks from hens on 50 mg were lower (P<0.01) at 6 weeks of age in 1970. This effect was not seen in 1971. Survival of chicks in brooders to 6 weeks of age was lower (P<0.01) in offspring of hens given 50 mg PCB weekly in 1970. No differences were found among offspring of treatment groups in 1971. Survival from 6 weeks of age to fall was similar in all groups. Overall survival from hatching to fall was less (P<.0.05) in offspring of hens given 50 mg weekly in both years combined. No differential effect was found between sexes for survival. PCB in doses varying front 10 mg to 210 mg daily caused hyper-excitability, weakness, tremoring, lack of appetite, lack of feathers, and a comatose death. Birds 11-weeks old given 10 or 20 mg PCB daily, birds 6 to 9 months old given 50 or 100 mg each 3.5 days, and adult hens given up to 50 mg once a week continued to eat. Eleven-week old birds given 210 mg daily stopped eating or those given 210 mg daily, the heaviest birds lost the greatest percentage of their weight (15 to 31 percent) before death occurred (1.3 to 4.3 days). Birds intentionally starved at the same time lost a greater percentage of weight (27 to 51 percent) before death (2.3 to 8.6 days). Some adult hens were given a single 50-mg capsule and samples of whole body, brain, liver, muscle, eggs, and feces were analyzed to determine patterns of storage and excretion. Levels of PCB were highest at 12 hours after capsule administration. Residues were highest in liver, followed by brain and muscle over 28 days following the single 50-mg capsule. From 94 to 98 percent of the administered dose was absorbed and 40.5 mg of the 50mg were in the body after 28 days. Hens were in a state of low egg production and excreted 4.2 mg in the eggs and 4.0 mg in the feces over 28 days. Excretion in the egg could be an important means of ridding the body of PCB. Four hens from the 1970 breeding experiment, given 17 capsules weekly containing 12.5 mg PCB and killed 1 week following the last capsule, had from 37 to 56 percent of the administered dose in their bodies. Four hens on the 50-mg level in 1970 had from 60 to 82 percent of the dose given. Five hens given 12.5 mg weekly for 16 weeks in 1971 had an average of 23.8 ppm PCB in their bodies 1 week after the last capsule, three hens had an average of 13.6 ppm after 3months on a clean diet, and three others had an average of 20.9 ppm after 6 months. Excretion was variable and slow. An analysis of brain, liver, and muscle tissues from dead and surviving birds fed PCB at various levels showed that brain residue levels from 300 to 400 ppm wet weight were indicative of death from FCB toxicosis. Liver and muscle levels were too variable to be useful in assessing cause of death. Administration of PCB decreased weights of heart and spleen (P <0. 01) at all levels given and increased weights of kidneys and livers in birds given 10- and 20-rng doses daily (P <0. 01) but not in birds given 210 mg daily. Splenic atrophy, where spleens were small, pale-tan color, and had wrinkled capsules resulting from depletion of lymphatic nodules, was characteristic of birds given PCB. PCB and dieldrin were given singly and jointly, and only additive, not synergistic, effects were noted. Livers of wild pheasants from Pennsylvania, Indiana, and South Dakota had no more than 2 ppm PCB. This indicates low-level contamination.
Use Of Waterfowl Production Areas By Ducks And Coots In Eastern South Dakota, Spencer Vaa
Use Of Waterfowl Production Areas By Ducks And Coots In Eastern South Dakota, Spencer Vaa
Electronic Theses and Dissertations
The use of Waterfowl Production Areas (WPA) by American coots (Fulica americana) and ducks was studied during 1970 and 1971 in east-central South Dakota The Eriksrud WPA, a type IV wetland with 55 acres of water area and 35 acres of upland, contained 188 coot nests during the 2-year study. Of the 188 coot nests, 178 hatched for a success rate of 95 percent. Average clutch size of 130 completed clutches was 8.4. Average size of 21 coot broods from 4 to 6 weeks of age was 6.1. Coot production on the Eriksrud area was estimated at 543 young per …
Use Of Eelctrophoresis To Determine Populations Of Pheasants In South Dakota, David George Montag
Use Of Eelctrophoresis To Determine Populations Of Pheasants In South Dakota, David George Montag
Electronic Theses and Dissertations
The ring-necked pheasant (Phasianus colchicus) is an important game bird, and various management techniques have been implemented in its behalf. One of the most common practices has been transplanting or stocking wherein pheasants are introduced into an area with a depleted population in hopes of increasing pheasant production. The effects of such programs are difficult to evaluate since there is no way of knowing if the introduced birds are in any way responsible for production changes which subsequently occur. If the taxonomic characteristics of the native and the introduced populations could be determined, the effect that introduced birds have on …