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Articles 17371 - 17400 of 17781
Full-Text Articles in Entire DC Network
Terrestrial Models: Introduction And Main Programs, D. W. Goodall, C. Gist
Terrestrial Models: Introduction And Main Programs, D. W. Goodall, C. Gist
Memorandum
No abstract provided.
Terrestrial Models: Plant Processes (Version I, Ii, Iii), W. Valentine
Terrestrial Models: Plant Processes (Version I, Ii, Iii), W. Valentine
Memorandum
No abstract provided.
Terrestrial Models: Animal Processes (Versions I, Ii), S. Payne
Terrestrial Models: Animal Processes (Versions I, Ii), S. Payne
Memorandum
No abstract provided.
Sensitivity Analysis, I. Noy-Meir, D. Goodall
Aquatic Models, Wayne Minshall
Decomposition And Mineralization In An Artemisia Tridentata Community In Northern Nevada, Peter L. Comanor
Decomposition And Mineralization In An Artemisia Tridentata Community In Northern Nevada, Peter L. Comanor
Memorandum
No abstract provided.
Measurements Of Carbon And Nitrogen Changes In Soil, Eugene E. Staffeldt, Kristina Bemond Vogt
Measurements Of Carbon And Nitrogen Changes In Soil, Eugene E. Staffeldt, Kristina Bemond Vogt
Memorandum
No abstract provided.
Prediction Of Plant-, Soil- And Air-Temperature On A Microscale In The Desert, Inge Dirmhirn, Frank Eaton
Prediction Of Plant-, Soil- And Air-Temperature On A Microscale In The Desert, Inge Dirmhirn, Frank Eaton
Memorandum
No abstract provided.
Diest, Food Preference And Reproductive Cycles Of Some Desert Rodents, Russell P. Balda, Clark E. Franz, O.J. Reichman, Kent M. Van De Graaff
Diest, Food Preference And Reproductive Cycles Of Some Desert Rodents, Russell P. Balda, Clark E. Franz, O.J. Reichman, Kent M. Van De Graaff
Memorandum
No abstract provided.
Consumption, Utilization And Modification Of Nutritional Resources By The Jackrabbit (Lepus Californicus) In The Mohave Desert, V.H. Shoemaker, K.A. Nagy, W.R. Costa
Consumption, Utilization And Modification Of Nutritional Resources By The Jackrabbit (Lepus Californicus) In The Mohave Desert, V.H. Shoemaker, K.A. Nagy, W.R. Costa
Memorandum
No abstract provided.
Captan Toxicity To Fathead Minnows (Pimephales Promelas), Bluegills (Lepomis Macrochirus), And Brook Trout (Salvelinus Fontinalis), Roger O. Hermanutz, Leonard H. Mueller, Kenneth D. Kempfert
Captan Toxicity To Fathead Minnows (Pimephales Promelas), Bluegills (Lepomis Macrochirus), And Brook Trout (Salvelinus Fontinalis), Roger O. Hermanutz, Leonard H. Mueller, Kenneth D. Kempfert
United States Environmental Protection Agency: Publications
The toxic effects of capt an on survival, growth, and reproduction of fathead minnows (Pimephales promelas) and on survival of bluegiIIs (Lepomis macrochirus) and brook trout (Salvelinus fontinalis) were determined in a flow-through system. In a 45-week exposure of fathead minnows, survival and growth were adversely affected at 39.5 μLg/Iiter. Adverse effects on spawning were suspected but not statisticaIly demonstrated at 39.5 and 16.5 μLg/Iiter. The maximum acceptable toxicant concentration (MATC), based on survival and growth, lies between 39.5 and 16.5 μLg/liter. The lethal threshold concentration (LTC) derived from acute exposures was 64 μLg/liter, …
Protection Of Our Fragile Upper Atmosphere, Clayton Clark
Protection Of Our Fragile Upper Atmosphere, Clayton Clark
Faculty Honor Lectures
Termination of U.S. government support for the Supersonic Transport, SST, may eventually cost the United States its leadership in aviation and billions of dollars in international trade losses, yet if the world wide SST program is allowed to continue, the costs to mankind as a result of damage to environmental resources could be much higher. The decision to terminate the project was heavily based upon concern for possible changes in the properties of the upper atmosphere as a result of SST operations in that realm, with consequent danger to plant and animal life on the Earth below. Briefly, the concern …
A Geochemical Study Of A Marsh Environment, Thomas F. Lytle, Julia Sever Lytle, Patrick L. Parker
A Geochemical Study Of A Marsh Environment, Thomas F. Lytle, Julia Sever Lytle, Patrick L. Parker
Gulf and Caribbean Research
The goal of this study was twofold: 1) chemically to characterize a specific salt marsh, the sediments and associated biota and 2) to establish clear relationships between the chemical substances residing in the sediments and similar or identical substances occurring in the biological specimens. In this particular study it was felt that the hydrocarbons would yield the most significant organic geochemical information. These compounds are ubiquitous but minor components of all organisms. Though their function is not entirely understood, it is known that they are concentrated in the waxy coatings of plants and most likely aid in the protective mechanisms …
A Quarter Century Of Geology At The Gulf Coast Research Laboratory (1948-1973), Ervin G. Otvos Jr.
A Quarter Century Of Geology At The Gulf Coast Research Laboratory (1948-1973), Ervin G. Otvos Jr.
Gulf and Caribbean Research
Overview of the history of geology courses and research at the Gulf Coast Research Laboratory in Ocean Springs, Mississippi.
Heavy Metal Concentrations In The Waters Of The Springfield Area, Missouri, Anita Louise Williams
Heavy Metal Concentrations In The Waters Of The Springfield Area, Missouri, Anita Louise Williams
Masters Theses
"Water samples consisting of streams, springs, lakes, deep wells, and shallow wells were collected from various locations around the Springfield area. These were analysed for concentrations of the heavy metals of lead, copper, cadmium, zinc, mercury, and iron. Heavy metal contents in the waters occasionally show local concentrations. The zinc content can be related to known minor mineralized areas around Springfield. Some iron content in the surface waters and shallow aquifers is contributed by the iron-bearing clays and pyrites in the shallow formations.
The ranges of heavy metal values in the Springfield area are in ppb: lead, 1 to 70; …
Corals Of The St. Louis Limestone In The Area Of Calhoun County, Illinois And St. Louis County, Missouri, William Earl Collins
Corals Of The St. Louis Limestone In The Area Of Calhoun County, Illinois And St. Louis County, Missouri, William Earl Collins
Masters Theses
"The St. Louis Limestone and its equivalent formations crop out from Alaska south to Sonora and from Arizona east to Virginia. The St. Louis, in most cases, is fossiliferous and contains numerous species of foraminifers, echinoderms, bryozoans, molluscans, brachipods, arthropods and coelenterates. Algal mounds and mats are common. The rugose coral fauna of the Middle Mississippian (Meramecian) St. Louis Limestone of southern Calhoun County, Illinois and northern St. Louis County, Missouri was studied to determine first what corals were present and second the validity of the names assigned to the previously described species. It was found that the binomen for …
Structure And Chemical Composition Of The Otoliths Of Cyprinus Carpio, Larry Paul Coen
Structure And Chemical Composition Of The Otoliths Of Cyprinus Carpio, Larry Paul Coen
Masters Theses
"The need for the study of microfossils such as foraminifera, conodonts, and otoliths as stratigraphic tools has been well established. However, disarticulated parts such as otoliths and conodonts cannot be effectively used unless they can be recognized. Otoliths, although somewhat unrecognized in the geological record, are far more abundant than articulated skeletons (Frizzell, 1965, p. 86). Therefore, much investigation is being conducted to reveal the origin, function, morphology, and usefulness of the otoliths of fishes.
In this investigation, the asteriscus, well developed only in Ostariophysins (of which the carp is a member), is studied for morphology. New tentative terms are …
Ordovician Corals Of The Williston Basin Periphery, Frank P. Caramanica
Ordovician Corals Of The Williston Basin Periphery, Frank P. Caramanica
Theses and Dissertations
Tabulate and rugose corals are described from the Ordovician Red River) Stony Mountain, and Stonewall Formations in southern Manitoba and the Ordovician Bighorn Formation in northern Wyoming. Fifty-four species, 12 of which are new, are distributed in 20 genera. The Flower Model of coral evolution, based on wall microstructure of colonial corals, is extended to include the septa! Microstructure of colonial and solitary corals. "Primitive" corals are characterized by non t-rabeculate walls and septa whereas "advanced" forms are characterizedby trabeculate walls and septa. "Mid-range" corals are those with intermediate stages of trabecular development in walls .and septa. Corals in the …
Feeding Efficiency In The Cave Salamander Haideotriton Wallacei, Stewart B. Peck
Feeding Efficiency In The Cave Salamander Haideotriton Wallacei, Stewart B. Peck
International Journal of Speleology
Selection for efficiency in food capture may be a dominant influence in the evolutionary biology of predaceous cave animals. A sample of 8 Haideotriton wallacei from a natural population contained 21 feeding boluses in their digestive tracts. Fourteen of these boluses contained food, demonstrating success in at least 67% of the feeding attempts.
La Colonisation De Quelques Grottes Du Jura Par Niphadobota Alpina Bezzi (Dipt. Tipulidae), M. J. Turquin
La Colonisation De Quelques Grottes Du Jura Par Niphadobota Alpina Bezzi (Dipt. Tipulidae), M. J. Turquin
International Journal of Speleology
Three new localities of Niphadobota (=Chionea) alpina in the French southern Jura allow the author to state that this insect’s climatic requirements explain the biogeography of the species; the origin of the colonization of caves by this dipteran is considered.
Biotope Et Description De Niphargus Altagahizi N. Sp., Amphipode Gammaridé Souterrain Du Liban, N. Alouf
Biotope Et Description De Niphargus Altagahizi N. Sp., Amphipode Gammaridé Souterrain Du Liban, N. Alouf
International Journal of Speleology
Description of a small warm cave situated along the Mediterranean shore; the temperature of water varies from 14 to 19°C. Inhabiting this cave is Niphargus altagahizi, a new species related to orcinus s.l. group. Description of this species and comparison with the other Lebanese species, N. nadarini.
Beobachtungen An Markierten Und Unmarkierten Köcherfliegen (Trichoptera) In Der Bärenhöhle Im Lonetal (Schwäbischer Jura), Klaus Dobat
International Journal of Speleology
1.The Bärenhöhle, one of the ten caves situated in the episodically water-bearing valley of the Lone (Swabian Jura), serves as summer quarters for the total of ten species of Trichoptera, most of which are Micropterna nycterobia and Stenophylax permistus. 2.Counts carried out in this cave from 1967-1972 and observations of flood and dry-periods of the Lone during the same years make evident that the number of Trichoptera flying into the cave seems to depend in a large measure on the seasonal activity of the creek: a steady flow of water makes the undisturbed development of larvae possible and results …
Temperature Preference Responses Of Some Aquatic, Cave-Adapted Crustaceans From Central Texas And Northeastern México, William R. Elliott, Robert W. Mitchell
Temperature Preference Responses Of Some Aquatic, Cave-Adapted Crustaceans From Central Texas And Northeastern México, William R. Elliott, Robert W. Mitchell
International Journal of Speleology
The temperature preference responses of five species of troglobite crustaceans were studied in a 15°-30°C gradient. Stygonectes hadenoecus, S. russelli and Asellus reddelli had no discernible temperature preferenda. Speocirolana bolivari had a weak preference for 20-30°C. Cirolanides texensis had a pronounced preference for 20-30°C, temperatures much warmer than that of its habitat. The lack of temperature preferenda in three species agrees with the hypothesis that imprisoned troglobites tend to lose responses to those environmental variables which are constant in caves. S. bolivari may retain its temperature selectivity because of a slow rate of cave-adaptation. It is hypothised that C. …
A New Troglobitic Isopod Of The Genus Lirceus (Asellidae) From Southwestern Virginia, With Notes On Its Ecology And Additional Cave Records For The Genus In The Appalachians, John R. Holsinger, Thomas E. Bowman
A New Troglobitic Isopod Of The Genus Lirceus (Asellidae) From Southwestern Virginia, With Notes On Its Ecology And Additional Cave Records For The Genus In The Appalachians, John R. Holsinger, Thomas E. Bowman
International Journal of Speleology
Lirceus usdagalun new species, the first known troglobitic species of the genus, is described from three caves in Lee County, Virginia. The potential taxonomic value of the endopod tip of the male second pleopod, heretofore dismissed as a diagnostic character in this genus, is pointed out. Some general ecological data for the new species are presented, and cave records for other populations of Lirceus spp. from the Appalachians are given.
Xlix Contribution To The Knowledge Of The Amphipoda. On Three Niphargus Species (Fam. Gammaridae) From The Balkans, Gordan S. Karaman
Xlix Contribution To The Knowledge Of The Amphipoda. On Three Niphargus Species (Fam. Gammaridae) From The Balkans, Gordan S. Karaman
International Journal of Speleology
Three Niphargus species from the Balkans are studied. Niphargus adbiptus, n. sp. is described from Ravanica cave in Serbia. Niphargus stygius ravanicanus S. Kar. 1943 from the same cave (Ravanica) is redescribed. N. valachicus Dobr. Man. 1933, is newly recorded from Bulgaria (Devnja).
Breeding And Fecundity In A Subterranean Mysid, Lepidomysis Longipes (Pillai And Mariamma), C. N. Nath
Breeding And Fecundity In A Subterranean Mysid, Lepidomysis Longipes (Pillai And Mariamma), C. N. Nath
International Journal of Speleology
The hypogean mysid, Lepidomysis longipes has a breeding period extending from December to April with the peak period in March. A secondary breeding period appears in August and September. The females have low fecundity and carry a maximum of nine eggs. Development is delayed due to lack of nourishment in the environment. The mysids breed only once a year.
The Evolution Of The Eastern North American Isopods Of The Genus Asellus (Crustacea: Asellidae) Part Ii, Laurence E. Fleming
The Evolution Of The Eastern North American Isopods Of The Genus Asellus (Crustacea: Asellidae) Part Ii, Laurence E. Fleming
International Journal of Speleology
This paper is the second in the three part series dealing with the evolution of the North American isopods of the genus Asellus. The generic status of Asellus is discussed with emphasis placed on the newly proposed genera of Henry and Magniez (1968). Use is made of comparative anatomical and where feasible statistical methods during this investigation. The first, shorter portion of the study deals with the presentation of evidence supporting the viewpoint that if "Pseudobaicalasellus” is to be considered a valid genus then it must include the members of the Cannulus Group of Steeves (1965). The …
Aspetti Ecologici Ed Evolutivi Del Popolamento Di Grotte Temperate E Tropicali: Osservazioni Sul Ciclo Biologico Di Alcune Specie Di Ptomaphagus (Coleoptera Catopidae), Valerio Sbordoni, Marina Cobolli-Sbordoni
Aspetti Ecologici Ed Evolutivi Del Popolamento Di Grotte Temperate E Tropicali: Osservazioni Sul Ciclo Biologico Di Alcune Specie Di Ptomaphagus (Coleoptera Catopidae), Valerio Sbordoni, Marina Cobolli-Sbordoni
International Journal of Speleology
Differences between tropical and temperate cave communities are an important topic in the actual biospeleological thinking. Among the most striking differences is the paucity of terrestrial troglobites in tropical caves. This fact may depend on the higher energy input into tropical caves which lessens the selection pressures for energy-economizing troglobite adaptations. Consequently evolutionary rates would be slowed in tropical caves and, in a date group, troglobites would appear later in such caves than in temperate ones with lower energy input. In order to investigate this point the authors studied the degree of adaptation to the cave environment in two species …
Press Reports, Walter A. Lawrance
The Relation Between Soil Characteristics, Water Movement And Nitrate Contamination Of Ground Water, Grant W. Thomas, Matthew Mcmahon
The Relation Between Soil Characteristics, Water Movement And Nitrate Contamination Of Ground Water, Grant W. Thomas, Matthew Mcmahon
KWRRI Research Reports
Soils from several areas in Kentucky were placed in columns and leached with Ca(NO3)2. Subsoils high in iron oxide were found to retard the leaching of nitrate very significantly. In other soils, the nitrate moved through as fast as or slightly faster than the water.
Field application of nitrogen to corn was most efficient when done in the spring or summer near the time that the corn takes it up. The one exception to this was a red soil, where fall application of nitrogen resulted in little loss due to the retarding effect mentioned in the …