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Introduction: One Hundred Years Of Natural History In Turkmenistan, Victor Fet Jan 1994

Introduction: One Hundred Years Of Natural History In Turkmenistan, Victor Fet

Biological Sciences Faculty Research

As part of the famous “Great Game” between the Russian and British Empires in Central Asia, Turkmenistan was the last colonial prize of the Russian tsars; its delineation from Afghanistan was completed only in the 1890s. The Russian Empire’s Transcaspian Region (Zakaspiiskaya Oblast) was roughly what Turkmenistan is today; its neighbors were the semi-independent emirate of Bokhara to the east and khanate of Khiva to the north, both remnants of medieval Muslim empires.

This book combines the results of basic scientific research in biogeography and ecology; its purpose is to give a fairly comprehensive account of the nature of Turkmenistan. …


Phytoplankton Relationships To Water Quality In Lake Drummond And Two Drainage Ditches, Christine G. Phillips, Harold G. Marshall Jan 1993

Phytoplankton Relationships To Water Quality In Lake Drummond And Two Drainage Ditches, Christine G. Phillips, Harold G. Marshall

Biological Sciences Faculty Publications

A twelve-month phytoplankton study was conducted in Lake Drummond and Washington and Jericho Ditches from December 1988 to November 1989. Four dominant phytoplankton groups were identified at these sites. These were the Bacillariophyceae, Cyanophyceae, Cryptophyceae and an autotrophic picoplankton component. Over the past 20 years there has been a decrease in the mean pH levels of Lake Drummond and the replacement of one its former major components, the Chlorophyceae, by the Cyanophyceae. Based on water quality analysis results and species diversity indices, Lake Drummond is classified as in an early eutrophic stage of development.


Coprolite Analysis: A Biological Perspective On Archaeology, Karl J. Reinhard, Baughn M. Bryant Jr Jan 1992

Coprolite Analysis: A Biological Perspective On Archaeology, Karl J. Reinhard, Baughn M. Bryant Jr

Karl Reinhard Publications

The most remarkable dietary remains recoverable from archaeological contexts are coprolites. Coprolites are desiccated or mineralized feces that are preserved in sheltered and open sites in arid regions, primarily in the New World. These dietary remains are remarkable from several perspectives. They typically contain a variety of macroscopic and microscopic remains that form interrelated data sets for the reconstruction of diets. Because contexts containing coprolites are typified by excellent preservation, the remains coprolites contain tend to be in better states of preservation than dietary remains recovered from nonfecal deposits. Coprolites also contain the well-preserved remains of intestinal parasites and pathogens …


"Introduction" (To Alfred Russel Wallace; An Anthology Of His Shorter Writings), Charles H. Smith Jan 1991

"Introduction" (To Alfred Russel Wallace; An Anthology Of His Shorter Writings), Charles H. Smith

DLPS Faculty Publications

No abstract provided.


Can Genetically Engineered Crops Become Weeds?, Kathleen H. Keeler Nov 1989

Can Genetically Engineered Crops Become Weeds?, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

There are significant differences if the distribution of weedy characteristics among weeds, normal plants, and crops. The world’s most serious weeds possess on the average 10 or 11 of these characters, a random collection of British plants have an average seven of the traits, and crop plants only five. For the average crop to become as “weedy” as the average weed, it would need to acquire five weedy traits. Even using the unlikely assumption that those traits are single loci in which a dominant mutation would provide the weedy character, this would require the simultaneous acquisition of five gene substitutions. …


Distribution And Status Of Rare And Endangered Mussels (Mollusca: Margaritiferidae, Unionidae) In Arkansas, John L. Harris, Mark E. Gordon Jan 1987

Distribution And Status Of Rare And Endangered Mussels (Mollusca: Margaritiferidae, Unionidae) In Arkansas, John L. Harris, Mark E. Gordon

Journal of the Arkansas Academy of Science

Knowledge of the distribution and population status of freshwater bivalves occurring in Arkansas has increased markedly during the past decade. Sufficient data has become available to delineate species which are rare and/or endangered within the state. Historical and recent records from Arkansas exist for four mussels currently listed as federally endangered species: the fat pocketbook (Potamilus capax), the pink mucket (Lampsilis orbiculata), Curtis' pearly mussel (Epioblasma florentina curtisi), and the turgid-blossom pearly mussel (Epioblasma turgidula). Ten additional mussels which occur or were thought to occur in Arkansas are being considered for federal protection by the United States Fish and Wildlife …


A Limnological Study Of 43 Selected Maine Lakes, Derrill J. Cowing, Matthew Scott Jan 1980

A Limnological Study Of 43 Selected Maine Lakes, Derrill J. Cowing, Matthew Scott

Maine Collection

A Limnological Study of 43 Selected Maine Lakes

by Derrill J. Cowing and Matthew Scott

U.S. Geological Survey : Water-Resources Investigations 80-69

Prepared in cooperation with the Maine Department of Environmental Protection

U.S. Geological Survey, 26 Ganneston Drive, August, Maine 04330


An Ecological Study Of The Algal Potamoplankton Communities Upstream And Downstream From A Sanitary Landfill On Riley Creek, Coles County, Illinois, Larry W. Coutant Jan 1976

An Ecological Study Of The Algal Potamoplankton Communities Upstream And Downstream From A Sanitary Landfill On Riley Creek, Coles County, Illinois, Larry W. Coutant

Masters Theses

No abstract provided.


Limnological, Ichthyological, And Parasitological Investigations On Arkansas Reservoris In Relation To Water Quality, John S. Carter, Carl E. Hoffman, Larry L. Olmsted, Raj V. Kilambi, Donald G. Cloutman, David A. Becker Jan 1974

Limnological, Ichthyological, And Parasitological Investigations On Arkansas Reservoris In Relation To Water Quality, John S. Carter, Carl E. Hoffman, Larry L. Olmsted, Raj V. Kilambi, Donald G. Cloutman, David A. Becker

Arkansas Water Resources Center Technical Reports

Lake Fort Smith, a 525 acre (212 ha) reservoir, was impounded in 1936 as a water supply for the city of Fort Smith. The reservoir is located on Clear Creek (Frog Bayou), a tributary of the Arkansas River, in the Boston Mountains 28 miles (45 km) northeast of the city of Fort Smith in Crawford County, Arkansas. A map and morphometric characteristics of Lake Fort Smith are given in Fig. 1 and Table I (Hoffman, 1951; Nelson, 1952). In 1956 Lake Shepherd Springs, a 750 acre (304 ha) impoundment, was created one mile upstream of Lake Fort Smith (Rorie, 1961). …


Seasonal Composition Of Zooplankton Of Lower Chesapeake Bay And Virginia Coastal Waters, Elizabeth W. Atkinson Jan 1973

Seasonal Composition Of Zooplankton Of Lower Chesapeake Bay And Virginia Coastal Waters, Elizabeth W. Atkinson

Biological Sciences Theses & Dissertations

Abstract unavailable.


Polychlorinated Biphenyls: Uptake By Daphnia And Residues In Crayfish From The Willamette River, John J. Salmon Jan 1972

Polychlorinated Biphenyls: Uptake By Daphnia And Residues In Crayfish From The Willamette River, John J. Salmon

Dissertations and Theses

Polychlorinated Biphenyls (PCB's) are organochlorine molecules which find various industrial and product applications. PCB's are of concern to biologists because they are toxic substances which have become global contaminants. They are also of concern to biologists and analytical chemists because they interfere with the determination of some organochlorine pesticide residues. PCB's were discovered to be environmental contaminants after they showed up as unidentified peaks in pesticide analysis using gas-liquid chromatography with an electron capture detector (GLC-EC).

In the present experiment standard GLC-EC techniques were used to assay PCB's in Daphnia experimentally contaminated in the laboratory and in crayfish from the …


Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation Jan 1971

Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation

Publications (WR)

Progressive increases in concentration of dissolved solids in the Colorado River water from Lake Powell to Imperial Dam seem to alter plankton dynamics and biological productivity of the river. Also, changes in biological productivity and micronutrients concentrations occur within the same reservoir. Development of a digital simulation model to predict micronutrients concentrations and biological productivity is necessary for diagnosing changes in plankton population and effluent-carrying capacity of the system. The objectives of the study are: (1) to determine trace metal balance at different locations in Lake Mead, (2) to measure biological productivity and conduct plankton population counts at each sampling …


Biological Studies Of Selected Reaches And Tributaries Of The Colorado River, Nelson Thomas, Federal Water Pollution Control Administration Oct 1968

Biological Studies Of Selected Reaches And Tributaries Of The Colorado River, Nelson Thomas, Federal Water Pollution Control Administration

Publications (WR)

This report fulfills the request of the Colorado River Basin Project, Denver, Colorado, to determine the effects of municipal and industrial wastes on the aquatic life in selected waters of the Colorado River Basin. These studies were conducted with the assistance of personnel from the Colorado River Basin Project.


Occurrence And Distribution Of Invertebrates In Lower Logan River, Nancy A. Erman May 1968

Occurrence And Distribution Of Invertebrates In Lower Logan River, Nancy A. Erman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study of bottom invertebrates on the lower Logan River, Logan, Utah was conducted from June 1966 to July 1967. One objective was to evaluate on a qualitative and quantitative basis the invertebrate populations above and below a sewage entry in the river. Another objective was to study the year-round fluctuations in the invertebrate population.

The greatest variety of invertebrates was found in the summer. Chironomidae and Baetis were the only two groups found in abundance over the entire year.

Populations were reduced during autumn when water levels rose, and they declined even more sharply during the spring flood.

At …


An Ecological Study Of The Algae And Mosses Of Cascade Springs, Wasatch County, Utah, Deanna Lynn Mccoard Aug 1967

An Ecological Study Of The Algae And Mosses Of Cascade Springs, Wasatch County, Utah, Deanna Lynn Mccoard

Theses and Dissertations

An ecological study was conducted at Cascade Springs, Wasatch county, Utah from August 1965, to June 1967. The algae and aquatic moss species were determined and ecological information about these organisms was obtained. Physical data were also collected: bicarbonates, carbonates, free carbon dioxide, hydroxides, oxygen, pH, and temperature. The physical environment of the water was found to be very constant. Tests taken at the different study sites were consistently similar, not only during each day, but all year around. No great variation of any kind was found in the water. In contrast to the water environment, the topography of the …


The Distribution Of Phytoplankton Along A 140 Mile Transect In The Chesapeake Bay, Harold G. Marshall Jan 1965

The Distribution Of Phytoplankton Along A 140 Mile Transect In The Chesapeake Bay, Harold G. Marshall

Biological Sciences Faculty Publications

The composition of phytoplankton progressively changed in the surface samples taken between Norfolk, Virginia and Cambridge, Maryland. These was an inverse relationship between the numbers of phytoplankters and zooplankters in the transect samples. Vertical stratification of the plankton was studied at two 24-hr, stations at the Great Wicomlco and Patuxent Rivers. The vertical centers of zooplankton and phytoplankton populations fluctuated over the study period and evidence is given to support a grazing phenomenon. Large concentrations of nannoplankters were found in all the plankton samples taken and is attributed to the collection procedure using the Van Dorn sampler.


A Review Of The Mites Of The Family Pseudocheylidae Oudemans, 1909 (Acarina, Prostigmata), Edward W. Baker, Warren T. Atyeo Jan 1964

A Review Of The Mites Of The Family Pseudocheylidae Oudemans, 1909 (Acarina, Prostigmata), Edward W. Baker, Warren T. Atyeo

Bulletin of the University of Nebraska State Museum (1924–2023)

Four genera and ten species are included; these are: Pseudocheylus biscalattts Ber1ese, 1888, P. americanus (Ewing), 1909, Stigmocheylus brevisetus Berlese, 1910, Anoplocheylus europaeus (Berlese), 1910, A. clavatus, n. sp., A. aegypticus, n. sp., A. protea (Womersley), 1935, Neocheylus natalensis Tragardh, 1906, N. nidcolus Lawrence, 1954, and N. collis, n. sp.


Introducing Aquatic Ecology To Ninth Graders, Inez P. Sutton Jul 1961

Introducing Aquatic Ecology To Ninth Graders, Inez P. Sutton

Masters Theses

Chapter I

Introduction

In discussing the basis for teaching high school biology, Van Deventer1 states, "...the present typical course in high school biology serves adequately neither the terminal student nor the college entrance student." He holds that today's courses present watered-down versions of college courses to the student before the intelligence of the student has matured enough to grasp such subject matter. As a result there is very little carry-over value from such courses, and the students may even develop a dislike for biology. This study constitutes an effort to understand these problems and to devise ways of solving …


The Fate Of The Indigenous, Arthur N. Wilcox Jan 1937

The Fate Of The Indigenous, Arthur N. Wilcox

Journal of the Minnesota Academy of Science

No abstract provided.


The Phytogeography Of Nebraska, Roscoe Pound, Frederic E. Clements Jul 1898

The Phytogeography Of Nebraska, Roscoe Pound, Frederic E. Clements

Papers in Systematics and Biological Diversity

From the preface we learn that this work is the result of nearly five years of active study of the floral covering of Nebraska, carried on by the members of the Botanical Seminar in the Botanical Survey of the State of Nebraska. The systematic study of the vegetation of Nebraska was begun by Dr. Bessey in 1884, and has since been carried on by him and his students, all previous collecting having been more or less desultory and unreliable. The Botanical Survey was organized in 1892, and its work has been directed to the collecting of specimens and observations for …