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The Hawaiian Cave Planthoppers (Homoptera: Fulgoroidea: Cixiidae) - A Model For Rapid Subterranean Speciation?, Hannelore Hoch Jan 1997

The Hawaiian Cave Planthoppers (Homoptera: Fulgoroidea: Cixiidae) - A Model For Rapid Subterranean Speciation?, Hannelore Hoch

International Journal of Speleology

After the successful colonization of a single ancestral species in the Hawaiian Islands, planthoppers of the cixiid genus Oliarus underwent intensive adaptive radiation resulting in 80 described endemic species. Oliarus habitats range from montaneous rain forests to dry coastal biotopes and subterranean environments. At least 7 independant evolutionary lines represented by different species have adapted to lava tubes on Molokai (1), Maui (3), and Hawaii Island (3). Behavioral and morphological studies on one of these evolutionary lines on Hawaii Island, the blind, flight- and pigmentless Oliarus polyphentus have provided evidence for reproductive isolation between allopatric populations which may in fact …


Hydrogeological And Hydrochemical Connection Between The Decatur City Spring And Crystal Lake, Benton County, Arkansas, Demetra O. Salisbury, Ralph K. Davis Jan 1997

Hydrogeological And Hydrochemical Connection Between The Decatur City Spring And Crystal Lake, Benton County, Arkansas, Demetra O. Salisbury, Ralph K. Davis

Journal of the Arkansas Academy of Science

Arkansas is ranked nationally in the production of broilers, laying hens, turkey, swine and beef cattle. These animals produce large volumes of waste, which are spread on pasture land as a method of disposal, as well as a source of fertilizer, resulting in nonpoint source contamination of surface water and ground water. One area of concern includes the Decatur City Spring, which provides municipal water for the city of Decatur. A total of eight sites in the surrounding area were monitored routinely for water quality parameters, including pH, specific conductance, and nitrate-nitrogen. Water temperature and spring and lake stage were …


Guide To Bahamian Ichnology: Pleistocene, Holocene, And Modern Environments: A Field Trip Guide, H. Allen Curran, Brian White, Mark A. Wilson Jan 1997

Guide To Bahamian Ichnology: Pleistocene, Holocene, And Modern Environments: A Field Trip Guide, H. Allen Curran, Brian White, Mark A. Wilson

Geosciences: Faculty Publications

This guide was prepared for the Fourth International Ichnofabric Workshop (IIW- 4) to be hosted by the Bahamian Field Station and held on San Salvador Island on March 15-22, 1997. About 35 scientists representing 15 countries are registered to attend the workshop.

The focus of discussion in the infonnal scientific sessions will be the uses of ichnofabric analysis in sedimentary geology. An ichnofabric is the texture or internal structure created within a sedimentary substrate from the bioturbating activity of organisms. Ichnofabric analysis is a new and emerging area of ichnology (the study of trace fossils), and its methods are proving …


Climatic Fluctuations And Tropical Troglobitic Evolution, Pedro Gnaspini Jan 1997

Climatic Fluctuations And Tropical Troglobitic Evolution, Pedro Gnaspini

International Journal of Speleology

No abstract provided.


Genetic Divergence And Evolutionary Times: Calibrating A Protein Clock For South-European Stenasellus Species (Crustacea Isopoda), Valerio Ketmaier, Roberto Argano, Marina Cobolli, Elvira De Matthaeis Jan 1997

Genetic Divergence And Evolutionary Times: Calibrating A Protein Clock For South-European Stenasellus Species (Crustacea Isopoda), Valerio Ketmaier, Roberto Argano, Marina Cobolli, Elvira De Matthaeis

International Journal of Speleology

We studied genetic divergence in a group of exclusively stygobiont isopods of the family Stenasellidae. In particular, we assessed evolutionary relationships among several populations of Stenasellus racovitzai and Stenasellus virei. To place this study in a phylogenetic context. we used another species of Stenasellus, S. assorgiai, as an outgroup. S. racovitzai occurs in Corsica, Sardinia and in the fossil islands of the Tuscan Archipelago, while S. virei is a polytypic species widely distributed in the central France and Pyrenean area. This vicariant distribution is believed to be the result of the disjunction of the Sardinia-Corsica microplate from …


Long Term Stability Of A Terrestrial Cave Community, Claudio Di Russo, Gianmaria Carchini, Mauro Rampini, Marco Lucarelli, Valerio Sbordoni Jan 1997

Long Term Stability Of A Terrestrial Cave Community, Claudio Di Russo, Gianmaria Carchini, Mauro Rampini, Marco Lucarelli, Valerio Sbordoni

International Journal of Speleology

We report data on the spatial structure and seasonal variation of the community of Valmarino cave, a medium sized sandstone cave, located a few kilometres from the coast line, in Central Italy. Due to both its habitat features and its relatively recent geological history, Valmarino cave is only inhabited by terrestrial, troglophilic elements, i.e facultative cave dwellers. By means of monthly censuses and density plot estimates we have investigated species abundance, diversity and their spatial organization, by considering separately samples from different cave sectors. Homogeneous sampling design allowed to compare series of samplings performed in 1974 and 1994. On the …


Ground Water, Robert F. Diffendal Jr. Jan 1997

Ground Water, Robert F. Diffendal Jr.

Department of Earth and Atmospheric Sciences: Faculty Publications

A geologic overview of the groundwater supply underlying Cheyenne County, Nebraska (1997).


Nearly Synchronous Climate Change In The Northern Hemisphere During The Last Glacial Termination, Larry V. Benson, James Burdett, Steve Lund, Michaele Kashgarian, Scott Mensing Jan 1997

Nearly Synchronous Climate Change In The Northern Hemisphere During The Last Glacial Termination, Larry V. Benson, James Burdett, Steve Lund, Michaele Kashgarian, Scott Mensing

United States Geological Survey: Staff Publications

The climate of the North Atlantic region underwent a series of abrupt cold/warm oscillations when the ice sheets of the Northern Hemisphere retreated during the last glacial termination (17,700–11,500 years ago). Evidence for these oscillations, which are recorded in European terrestrial sediments as the Oldest Dryas/Bølling/ Older Dryas/Allerød/Younger Dryas vegetational sequence, has been found in Greenland ice cores. The geographical extent of many of these oscillations is not well known, but the last major cold event (the Younger Dryas) seems to have been global in extent. Here we present evidence of four major oscillations in the hydrological balance of the …


The Use Of Bauxite Residue As A Soil Amendment In The Peel-Harvey Coastal Plain Catchment - Report On Results Of 1995 Environmental Monitoring Program, Mark Rivers Nov 1996

The Use Of Bauxite Residue As A Soil Amendment In The Peel-Harvey Coastal Plain Catchment - Report On Results Of 1995 Environmental Monitoring Program, Mark Rivers

Natural resources published reports

This report was submitted in accordance with the recommendations of the Environmental Protection Authority (EPA) who have stated that a monitoring program shall be undertaken by Agriculture Western Australia within six months of the widespread use of bauxite residue as a soil amendment. Although this widespread use of bauxite residue has not yet formally commenced, pre-emptive monitoring has been undertaken in order to gain some understanding of the general environmental characteristics of the Peel-Harvey catchment and, in particular, the characteristics and quality of the water flowing through the catchment.

It represents the second annual report submitted to the EPA describing …


Western Australian Salinity Action Plan, Agriculture Western Australia, Department Of Conservation And Land Management, Department Of Environmental Protection, Water And Rivers Commission Nov 1996

Western Australian Salinity Action Plan, Agriculture Western Australia, Department Of Conservation And Land Management, Department Of Environmental Protection, Water And Rivers Commission

Natural resources published reports

Salinity is one of the State's most critical environmental problems, threatening major economic and social consequences. It is preventable and, in the long term, reversible. Complete elimination is not realistic, but we can dramatically reduce its impact.

Salinity is caused by replacing deep-rooted native plants with shallow-rooted crops and pastures. More rainfall passed below the root zone and accumulates as groundwater so that watertables rise. The groundwater mobilises natural salts in the soil as it rises and carries them towards the surface, eventually degrading land and streams.


Earth News, Fall 1996, Department Of Earth Science, University Of Northern Iowa. Oct 1996

Earth News, Fall 1996, Department Of Earth Science, University Of Northern Iowa.

Earth News

Inside this issue:

--- News from the Earth Science Staff
--- Profile: Ken De Nault
--- Earth Science Majors
--- Sigma Gamma Epsilon - Gamma Sigma Chapter
--- Gifts to the Department of Earth Science
--- 1996 Scholarships and Award Recipients
--- Student Research Presentations
--- 1996 Earth Science Graduates
--- Special Alumni Newsetter Profile - Lee Potter
--- Earth Science Alumni Notes


Managing Pastures For Long-Term Prosperity, Hugh Pringle, Jenny Riches Sep 1996

Managing Pastures For Long-Term Prosperity, Hugh Pringle, Jenny Riches

Natural resources published reports

A Workshop held by the Sandstone Land Conservation District Committee

Lake Mason Station

April 1994

A workshop hosted by Sandstone Land Conservation District Committee (LCDC) was held at Lake Mason station on 28 April 1994. This workshop was based on two previous workshops hosted by the Kalgoorlie and north-eastern Goldfields LCDCs in May 1991 (Pringle et al. 1992). The success of the earlier workshops prompted the rangeland survey team in association with the Sandstone LCDC and the Kalgoorlie District Office of Agriculture Western Australia to initiate the project.

The aims were to provide a summary of local wisdom regarding pasture …


Spatial And Temporal Variability In The Distribution Of Nitrate In An Agriculturally-Impacted Aquifer, Cass County, Michigan, Caroline Lovetere Aug 1996

Spatial And Temporal Variability In The Distribution Of Nitrate In An Agriculturally-Impacted Aquifer, Cass County, Michigan, Caroline Lovetere

Masters Theses

Ground-water sampling in a shallow unconfined aquifer within a predominantly agricultural area in southwestern Michigan indicated spatial and temporal variability in the distribution of nitrate. The unconfined aquifer, which is about 40 feet thick, consists of glacially-deposited sand and gravel with interbedded clay lenses and is separated from a lower semi-confined aquifer by a 3-to 26-feet-thick till layer.

The site of the study was a 47-acre agricultural field, characterized by corn and alfalfa hay production, to which hog manure and commercial fertilizers were frequently applied. The shallow water table and relatively permeable glacial sands in the vadose zone combined to …


An Avian Botulism Epizootic Affecting A Nesting Site Population Of Presbyornis : On A Carbonate Mudflat Shoreline Of Eocene Fossil Lake, V. Leroy Leggitt Jun 1996

An Avian Botulism Epizootic Affecting A Nesting Site Population Of Presbyornis : On A Carbonate Mudflat Shoreline Of Eocene Fossil Lake, V. Leroy Leggitt

Loma Linda University Electronic Theses, Dissertations & Projects

The shorebird-duck mosaic bird, Presbyornis, is best known from the Eocene Green River Formation where it often occurs in local monospecific bonebeds, suggestive of mass mortality events. The sedimentology, paleontology, taphonomy, XRD mineralogy, and the carbonate stable isotope signature (δ18O) of one of these bonebeds was studied on the southern margin of Eocene Fossil Lake.

A series of 408 standardized radiographs were used to construct the first large scale radiograph aided taphonomic map of a vertebrate fossil quarry (3,874 bones were recorded in 11.5 m2). A small group of 100 bones (including a complete skull …


Thermal Tolerances Of Platte River Fishes: Field And Laboratory Studies, Brett P. Fessell May 1996

Thermal Tolerances Of Platte River Fishes: Field And Laboratory Studies, Brett P. Fessell

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Chronic Effects Of Baseflow Levels Of Atrazine On Platte River Algae, Karen J. Nelson May 1996

Chronic Effects Of Baseflow Levels Of Atrazine On Platte River Algae, Karen J. Nelson

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Trace Element Analysis Of Selected Springs In The Virgin River Basin, Mary A. Yelken May 1996

Trace Element Analysis Of Selected Springs In The Virgin River Basin, Mary A. Yelken

UNLV Theses, Dissertations, Professional Papers, and Capstones

Spring water from 23 springs in and near the Virgin River Basin (southwestern Utah, northwestern Arizona, and southeastern Nevada) was collected and analyzed for chemical concentrations. Trace elements and major ion chemistry was used to determine the potential for utilizing water chemistry to provide information on spring water source and flow pathways. Principal Component Analysis (PCA), rare earth element (REE) normalization patterns, and mineral equilibrium modeling (PHREEQE) techniques were used to analyze the data set. Four major spring water groups were displayed by the PCA, based on similarities in water chemistry. The analyses suggest that spring water chemistry is a …


Residence Time Of Groundwater Issuing From The South Rim Aquifer In The Eastern Grand Canyon, Jim Fitzgerald May 1996

Residence Time Of Groundwater Issuing From The South Rim Aquifer In The Eastern Grand Canyon, Jim Fitzgerald

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the eastern Grand Canyon, secondary porosity created by north trending faults, folds, and breccia pipes, facilitates groundwater flow through the South Rim carbonate aquifer. Springs associated with the South Rim Aquifer have low 3H concentrations, [Ca2+]/[Mg2+] rations close to unity, and variable uranium concentrations. For a geochemical comparison, springs are subcategorized on the basis of geology and discharge. Type I springs are associated with high-angle normal faults and have high discharge rates. These springs discharge Ca2+ - Mg2+, HCO3- waters, have 3H concentrations <2 TR, and 234U/238U activity …


A Study Of The Chemical And Physical Interactions Between A Wetland And A Shallow Aquifer In Cass County, Michigan, Lisa Marie Anderson Apr 1996

A Study Of The Chemical And Physical Interactions Between A Wetland And A Shallow Aquifer In Cass County, Michigan, Lisa Marie Anderson

Masters Theses

A study of the ground-water chemistry and flow direction adjacent to a wetland was performed in a major hog producing area. Nested piezometers, consisting of wells 7 to 18 feet deep, were installed around the wetland to determine the vertical distribution of hydraulic head and water-quality parameters. Piezometer elevations were surveyed to determine precise ground-water elevations to delineate the ground-water flow regime around the wetland. Water samples were taken at three different times to analyze water quality and seasonal variations. Analytical parameters included major ions, redox sensitive parameters (DO, nitrate-N, ammonia, iron, and sulfate), and total organic carbon.

Water level …


Esperance Region Catchment Planning Strategy, John Platt, Brendan Nicholas, Rod Short, Stephen Gee Apr 1996

Esperance Region Catchment Planning Strategy, John Platt, Brendan Nicholas, Rod Short, Stephen Gee

Natural resources published reports

The Esperance Region Catchment Planning Strategy project was initiated by the Esperance Land Conservation District Committee.

This report provides a reference document for farmers and other land managers such as government agencies and local government, and should help them to strategically focus their catchment planning activities.

It will help land managers to identify the major catchments and land systems in their area, management issues for long term sustainability, and a regional strategy for catchment planning.

Catchment planning involves both technical and social processes.

Technically it is a process of planning the sustainable use of water resources within a catchment.


Long-Term Surveillance Plan For The South Clive Disposal Site, Clive, Utah, Jacobs Engineering Group Inc. Mar 1996

Long-Term Surveillance Plan For The South Clive Disposal Site, Clive, Utah, Jacobs Engineering Group Inc.

All U.S. Government Documents (Utah Regional Depository)

No abstract provided.


Marketing Options For Quality Kentucky Alfalfa Hay, Tom Keene Feb 1996

Marketing Options For Quality Kentucky Alfalfa Hay, Tom Keene

Kentucky Alfalfa and Stored Forage Conference

As today's farmer becomes more and more business like, running his farming operation as a commercial business, the production of alfalfa hay should be treated no differently. When the farmer makes the decision to plant alfalfa, he should have already done a great deal of research and given a great deal of thought into the markets he is going to try to target for his product. Any successful commercial business looks into market potential even before production begins, whether they produce toys, cars, appliances, computers, etc. Alfalfa hay production should be no different in regards to seeking out various markets …


Utilizing Alfalfa Hay In Horse Diets, Laurie Lawrence Feb 1996

Utilizing Alfalfa Hay In Horse Diets, Laurie Lawrence

Kentucky Alfalfa and Stored Forage Conference

All horses need fiber in their diets. Forages, usually as pasture or hay, are the primary sources of fiber in most rations. The exact amount of hay that a horse will eat on a daily or yearly basis will depend on the size of the horse, the class of the horse (pregnant, working, etc) and the type of hay being fed. The type and amount of other feeds in the ration will also impact the amount of hay consumed, but in general, horse owners/managers should try to maximize forage intake and then supplement with grain or other feeds to meet …


Fencing And Watering Systems For Grazing Alfalfa, Larry Turner Feb 1996

Fencing And Watering Systems For Grazing Alfalfa, Larry Turner

Kentucky Alfalfa and Stored Forage Conference

Controlled or rotational grazing can result in better utilization of the forage resources on your farm. By better forage management through controlled grazing, you can increase profitability of cattle/forage systems. To effectively develop a controlled grazing system, however, fencing must be used to subdivide the pasture into sub-fields or paddocks. The animals may then be rotated among the paddocks to optimize forage and beef or dairy production from the system. Alfalfa grazing can play an important part in such a system. By using alfalfa, additional grazing management options are available, including avoiding high-endophyte fescue in hot summer periods thereby gaining …


Opportunities For Alfalfa As A Grazing Crop In Kentucky, Ken Johnson Feb 1996

Opportunities For Alfalfa As A Grazing Crop In Kentucky, Ken Johnson

Kentucky Alfalfa and Stored Forage Conference

As we think about the possibilities of alfalfa as a grazing crop, maybe we need to look at some of the limitations and where alfalfa may fit into Kentucky producers programs.

When looking at Kentucky's land area of 25 million acres we see that nearly half is in woodland. Of the 12 million acres remaining; about 3 million is in row crops, 2 million in hay, 2 million in non farm uses, and the rest is pasture. That is about 5 million acres in pasture or at least available to the pastured. With at least 7 million acres in hay …


Grazing Alfalfa: Putting The Puzzle Together, Garry D. Lacefield, Jimmy C. Henning, David Stalion Feb 1996

Grazing Alfalfa: Putting The Puzzle Together, Garry D. Lacefield, Jimmy C. Henning, David Stalion

Kentucky Alfalfa and Stored Forage Conference

Interest in alfalfa as a grazing crop has increased dramatically over the past decade. There are many research and demonstrations being conducted in Kentucky and across the U.S. as we continue to investigate and learn more about alfalfa's role in forage-based livestock production.

Listed below are some of the reasons farmers, researchers and agribusiness personnel are excited about the opportunity for alfalfa as a grazing crop.


The Use Of Hydrochemistry To Identify Potential Processes Operating In The Saddle Mountains Basalt Aquifer And The Use Of The Nitrate-Nitrogen Isotope To Distinguish Between Potential Sources Of Nitrate To The Shallow Alluvial Aquifer In The Lower Umatilla Basin, Oregon, Margot Truini Feb 1996

The Use Of Hydrochemistry To Identify Potential Processes Operating In The Saddle Mountains Basalt Aquifer And The Use Of The Nitrate-Nitrogen Isotope To Distinguish Between Potential Sources Of Nitrate To The Shallow Alluvial Aquifer In The Lower Umatilla Basin, Oregon, Margot Truini

Dissertations and Theses

Nitrate concentration in excess of national drinking-water standards (10 mg/l) are present in the shallow alluvial aquifer and Saddle Mountains Basalt (SMB) aquifer in the Lower Umatilla Basin, Oregon. To determine sources responsible for elevated nitrate concentrations in the SMB aquifer mass-balance and reaction-path models (NETPATH and PHREEQE) were used to understand observed geochemical trends. Nitrate-nitrogen isotopes were used to distinguish potential nitrate sources in the shallow alluvial aquifer. NETPATH-validated simple water/rock reactions in the SMB aquifers in Irrigon (dissolving glass, precipitating smectite, dissolving or precipitating calcite, and cation exchange) using constituents (calcium, magnesium, sodium and carbon). Diversity of composition …


Geologic History Of Ash Hollow State Historical Park, Nebraska, Robert F. Diffendal Jr., Roger K. Pabian, J. R. Thomasson Feb 1996

Geologic History Of Ash Hollow State Historical Park, Nebraska, Robert F. Diffendal Jr., Roger K. Pabian, J. R. Thomasson

Conservation and Survey Division: Faculty and Staff Publications

Contents:

Introduction
Acknowledgments
Cautions
General Stratigraphy
Oligocene Series-White River Group-Brule Formation-Whitney Member
Miocene Series-Ogallala Group-Ash Hollow Formation
Pliocene Series-Broadwater Formation
Quaternary deposits
Older colluvium and loess
Younger colluvium and alluvium
General Paleontology
Evidence of past life: fossils and subfossils
Collecting fossils
Vertebrate fossils
Fossils from the Whitney Member of the Brule Formation
Plants
Invertebrates
Vertebrates
Fossils from the Ash Hollow Formation
Plants
Invertebrates
Vertebrates
Fossils from the Broadwater Formation
Plants
Vertebrates
Quaternary fossils
Plants
Invertebrates
Vertebrates
Additional studies of Nebraska fossils
Geologic History
Prehistory and History
References
Appendices I-IV


Soils Of The Ivanhoe West Bank East Kimberley Western Australia, C Grose, N Schoknecht Jan 1996

Soils Of The Ivanhoe West Bank East Kimberley Western Australia, C Grose, N Schoknecht

Resource management technical reports

A brief assessment of the soils of 2,064 ha of land on the Ivanhoe West Bank and their suitability for irrigated agriculture was conducted in May-June 1994. Sandy or loamy soils occur on broad levees adjacent to the Ord River, and areas of 'black soil' and 'red soil' plains occur behind these levees. Some areas of the red soil plain and levees are deeply dissected, and occasional active erosion is evident.


Soils Of The Knox Creek Plain East Kimberley Western Australia And Northern Territory, C Grose, Noel Schoknecht Jan 1996

Soils Of The Knox Creek Plain East Kimberley Western Australia And Northern Territory, C Grose, Noel Schoknecht

Resource management technical reports

An assessment of the soils and landforms of approximately 12,000 ha in the Knox Creek Plain in Western Australia and the Northern Territory was conducted in May and June 1994. Seventeen map units were identified and their soils, landform and vegetation characteristics were described. Grey or brown cracking clays predominate on the plain, however variable red or brown soils on the coarser alluvium of remnant levees are common in the south and south-east.