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Nitrogen And Carbon Isotope Studies Of A Bat Guano Core From Eagle Creek Cave, Arizona, Usa, Hiroshi Mizutani, Donald A. Mcfarlane, Yuko Kabaya Feb 1992

Nitrogen And Carbon Isotope Studies Of A Bat Guano Core From Eagle Creek Cave, Arizona, Usa, Hiroshi Mizutani, Donald A. Mcfarlane, Yuko Kabaya

WM Keck Science Faculty Papers

Nitrogen and carbon isotope ratios were studied in a stratified deposit of guano of Mexican Free-tailed bats in Eagle Creek Cave, Arizona, U.S.A. Little diagenetic change was observed over the 25-year time span of the guano deposit. High aridity and reduced circulation of air in the cave are hypothesized to have slowed the normally rapid decomposition of the excreta and the subsequent escape of resultant ammonia. The results suggest the high dependency of the speed of diagenetic change on specific physical and other conditions of the caves and indicate that great care need be exercised in the interpretation of the …


Carbon And Nitrogen Isotopic Signatures Of Bat Guanos As A Record Of Past Environments, Hiroshi Mizutani, Donald A. Mcfarlane, Yuko Kabaya Feb 1992

Carbon And Nitrogen Isotopic Signatures Of Bat Guanos As A Record Of Past Environments, Hiroshi Mizutani, Donald A. Mcfarlane, Yuko Kabaya

WM Keck Science Faculty Papers

Carbon and nitrogen isotope ratios were measured for various ecogeochemical samples relevant to bat guano ecosystems. In particular, ca. 800-year-old subfossil guano from Jackson's Bay Cave Compex, Jamaica, yielded ratios similar to the modern guano from other Jamaican bat caves but quite different from modern guano of the same area. Diagenetic change and differences in bat food habits were unlikely explanations for the observation. Instead, insects that feed on C4 and CAM plants were the main prey for the bats in present Jackson's Bay area, while the ultimate source of organic matter for bats in other Jamaican caves and for …


Water Quality In The Kentucky River Basin, Daniel I. Carey Jan 1992

Water Quality In The Kentucky River Basin, Daniel I. Carey

Information Circular--KGS

Data gathered up to 1990 suggest that water pollution problems existed throughout the Kentucky River Basin. Fecal coliform bacteria in streams was a widespread problem because of the inadequate treatment of municipal wastes, failing septic systems, and agricultural runoff. Iron, lead, manganese, mercury, and silver exceeded State standards and Federal guidelines for drinking water and aquatic life at most of the sample sites for a majority of samples. Aquatic life in many smaller streams in the Knobs region was reduced by chloride discharges from oil and gas operations, according to the Kentucky Division of Water. Organic enrichment and high nutrient …


Effects Of Seeder Design And Seed Placement On Seedling Size And Cull Rates At Western Forest Nurseries, United States Department Of Agriculture, Forest Service Jan 1992

Effects Of Seeder Design And Seed Placement On Seedling Size And Cull Rates At Western Forest Nurseries, United States Department Of Agriculture, Forest Service

Forestry

Nursery plots sown with the Summit Precision Seeder and the Oyjord Seeder were compared with plots oversown and hand thinned to desired spacings. We studied 26 seedlots of nine conifer species at five Forest Service, U.S. Department of Agriculture, nurseries. Results varied with nursery, species, and seed characteristics. Thinned plots produced less clumping and fewer gaps between seedlings, but showed little or no difference in seedling size, nor in the number of acceptable seedlings.


A Partial Glossary Of Elk Management Terms, United States Department Of Agriculture, Forest Service Jan 1992

A Partial Glossary Of Elk Management Terms, United States Department Of Agriculture, Forest Service

Forestry

This glossary helps define terms that have been misused during forest planning. Terms that were developed from research on the influences of timber sales and roads during the summer months have been used inappropriately when referring to winter range, hunting seasons, and other conditions. The glossary is based on the results of an "Elk Management Terminology Workshop" held at the University of Montana's Lubrecht Experimental Forest on April 3-4, 1990.


Plant Community Diversity After Herbicide Control Of Spotted Knapweed, United States Department Of Agriculture, Forest Service Jan 1992

Plant Community Diversity After Herbicide Control Of Spotted Knapweed, United States Department Of Agriculture, Forest Service

Herbicides and Pesticides

Herbicides were applied to four west-central Montana sites with light to moderate spotted knapweed (Centaurea maculosa Lam.) infestations. Althought knapweed suppression was high, 2 years after the spraying the communities were not converted to grass monocultures. No large declines in plant diversity were caused by the herbicides, and small depressions were probably transitory. By the third year, diversity had increased.


Paleoenvironmental Analysis Of Three Subfossil Coleopteran Faunas From The Toklat River Drainage, Central Alaska, Lisa L. Churchill Jan 1992

Paleoenvironmental Analysis Of Three Subfossil Coleopteran Faunas From The Toklat River Drainage, Central Alaska, Lisa L. Churchill

Senior Scholar Papers

Three sediment samples were collected from exposures along the Tok lat River. Central Alaska and analyzed for subfossil Coleopteran remains. Two samples arc Holocene in age (650 ± b.p .. and submodem) and the other is believed to be laic Pleistocene in age, based on stratigraphic interpretations. The Pleistocene fauna was representative of a tundra environment adjacent to a fluvial system. The older Holocene sample was indicative of a point bar deposit wi rh sl ightly moister conditions. although rhe occurrence of several tundra species was also noted. These tundra species were evidently able to make the transition from their …


Stubble : Friend And Foe, Department Of Agriculture And Food, Western Australia Jan 1992

Stubble : Friend And Foe, Department Of Agriculture And Food, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

Several articles in this issue of the Journal of Agriculture discuss some of the important issues of stubble management. The articles are condensed from some of the papers presented at a stubble workshop at Geraldton in 1991.


New Yellow Serradella Varieties For Low Rainfall Pastures, Clinton Revell Jan 1992

New Yellow Serradella Varieties For Low Rainfall Pastures, Clinton Revell

Journal of the Department of Agriculture, Western Australia, Series 4

Large areas of acidic, sandy soils in Western Australia's low and medium rainfall, wheatsheep areas are suited to the pasture legume, yellow serradella.

In the past, a lack of varieties with suitable maturity has limited the use of this species.

New varieties developed in Western Australia and significantly earlier in maturity than traditional types can now extend the use of yellow serradella into these regions.


Natural And Technological Disasters: Causes, Effects And Preventive Measures, Nazrul I. Khandaker Jan 1992

Natural And Technological Disasters: Causes, Effects And Preventive Measures, Nazrul I. Khandaker

Publications and Research

No abstract provided.


Current Research On Soil Nitrate Testing For Corn In Kentucky, John H. Grove Jan 1992

Current Research On Soil Nitrate Testing For Corn In Kentucky, John H. Grove

Soil Science News and Views

Concern has been expressed that growers do not have the "slte-specific" information they need for more efficient nitrogen (N) fertilizer management on a field-by-field basis. Soil testing has routinely been used to guide recommendations for phosphorus, potassium, and lime additions to individual fields, but effective soil N test procedures have long eluded soil scientists working in warm, humid regions with substantial winter rainfall. Now, recent research suggests that a new soil test procedure has some potential to guide fertilizer N applications for corn. The purpose of this report is to define the concept of soil nitrate testing; to describe how …


Factors Affecting Crop Response To Liming, Kenneth L. Wells, J. L. Sims Jan 1992

Factors Affecting Crop Response To Liming, Kenneth L. Wells, J. L. Sims

Soil Science News and Views

Soil acidity levels directly affect the rate, kinds, and degree of chemical reactions which take place in soil. Crops respond to varying degrees to these chemical reactions. For the most part, these reactions affect the solubility of mineral elements in soil and the activity of the soil's biological processes. As a result, the availability of many plant nutrient elements is regulated by soil acidity. The level of availability of plant required nutrients can be adequate, deficient, or toxic to the plant, depending on the nutrient, soil acidity, and the crop. That is why measurement of soil acidity is regarded by …


Distribution Of Foraminifera And Pollen In Coastal Depositional Environments Of The Southern Delmarva Peninsula, Virginia, U.S.A., Han Jun Woo Jan 1992

Distribution Of Foraminifera And Pollen In Coastal Depositional Environments Of The Southern Delmarva Peninsula, Virginia, U.S.A., Han Jun Woo

OES Theses and Dissertations

The coastal zone of the southern Delmarva Peninsula exhibits a wide variety of barrier island system subenvironments. This study investigates whether 20 a priori subenvironments can be distinguished from each other on the basis of abiotic environmental variables, pollen assemblages, living foraminiferal populations, and total (living plus dead) foraminiferal assemblages.

The physical data collected from the coastal zone were subjected to canonical variate analysis which discriminated 83% of the stations in 19 groups. These groups were clustered into two internally overlapping sets which represented the inside and outside of the inlet.

Twenty-two pollen types were found in low-energy marsh and …


Denitrification In The Elk Valley Aquifer, Northeastern North Dakota, Gale G. Mayer Jan 1992

Denitrification In The Elk Valley Aquifer, Northeastern North Dakota, Gale G. Mayer

Theses and Dissertations

Biological denitrification controls nitrate distribution in the Elk Valley aquifer, which underlies approximately 725 square kilometres of northeastern North Dakota and provides drinking water for farms and rural communities in the area. Increased irrigation has raised concerns over potential contamination from agricultural practices. The purpose of this study was to establish the role of biological denitrification in minimizing concentration and distribution of nitrate and to determine the effect irrigation practices have on groundwater flow and nitrate distribution in the saturated zone.

The aquifer is unconfined and consists of up to 20 metres of glacial outwash and deltaic shale-rich sand deposits. …


The Origin Of Metalliferous Argillites In The Shoal Arm Formation Of North-Central Newfoundland, Volker Brüchert Jan 1992

The Origin Of Metalliferous Argillites In The Shoal Arm Formation Of North-Central Newfoundland, Volker Brüchert

Geology Theses and Dissertations

The Middle Ordovician Shoal Arm Formation, which is located in the central volcanic belt of north-central Newfoundland, is a tripartite assemblage of hematitic argillites, grey cherts, and black shales directly underlying a flysch sequence. The hematitic argillites are enriched in Fe, Mn, Ni, Pb, and Co. Factor analysis and principal component analysis indicate the presence of a hydrothermal component, presumably derived from hydrothermal activity in the coeval Lawrence Head volcanics. Unusual, (?) calcareous Mn-Fe-oxide nodules are present in the top parts of turbidites in the hematitic argillites. Electron microprobe analysis of a color transition from a red to a green …


How Stubble Affects Organic Matter, Plants And Animals In The Soil, Judy Tisdall Jan 1992

How Stubble Affects Organic Matter, Plants And Animals In The Soil, Judy Tisdall

Journal of the Department of Agriculture, Western Australia, Series 4

Cereal yields have not increased greatly in Australia over the past 30 years and they are still only about half the potential determined by rainfall. One of the reasons for these low yields is our fragile soils, worsened by traditional systems of tillage and the burning of stubble. These systems reduce the levels of organic matter and biological activity in soil


Glacial Deposits, Vol. 20, 1991-1992, Department Of Geography-Geology Jan 1992

Glacial Deposits, Vol. 20, 1991-1992, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


River Channel Stability And The Implications For Fish Habitat, John T. Beebe Jan 1992

River Channel Stability And The Implications For Fish Habitat, John T. Beebe

Theses and Dissertations (Comprehensive)

The purpose of this project was to investigate various aspects of river channel stability as they relate to fish habitat. Two headwater creeks of the Credit River system, Black and Silver Creeks, and their confluent stream, the West Credit River in Southern Ontario were used in the study. Thirty-five cross-sections were established and revisited during four flow regimes, summer base flow, fall secondary peak flow, spring melt-high flow and post-spring high flow. Measurements of width, depth and temperature were taken at these times. Water samples were taken for determination of suspended sediment concentration. Channel stability was investigated in relation to …


Hydrogeologic Characterization Of A Discharge Wetland In Northeastern Grand Forks County, North Dakota, Dean R. Goebel Jan 1992

Hydrogeologic Characterization Of A Discharge Wetland In Northeastern Grand Forks County, North Dakota, Dean R. Goebel

Theses and Dissertations

Soil salinization associated with saline groundwater discharge results in decreased agricultural production in the central glacial Lake Agassiz plain of North Dakota. Saline discharge occurs in a belt of ephemeral wetlands in the lake plain. The physical and chemical hydrology of .the Lunby-stewart saline discharge wetland were investigated in order to provide information which could facilitate land management strategies applicable to this and other discharge wetlands.

Hydrologic data used to characterize the wetland were obtained from monitoring wells, staff gages, precipitation gages, borings, and earth electrical resistivity soundings. Temporal and spatial variations were observed in the water table, the vertical …


The First Documentation Of A Lower Middle Pennsylvanian Upland Flora From The Eastern Margin Of The Eastern Interior Basin (Illinois Basin), Vicki J. Comer Jan 1992

The First Documentation Of A Lower Middle Pennsylvanian Upland Flora From The Eastern Margin Of The Eastern Interior Basin (Illinois Basin), Vicki J. Comer

Masters Theses

The primary objective of this study is to reconstruct the paleofloristics of an unnamed shale of lower Middle Pennsylvanian age. The shale is periodically exposed in the highwall of the Ashboro Pit, Log Cabin Coal Company, Clay County, Indiana. This will be the first upland fossil flora to be described from the eastern margin of the Eastern Interior Basin (Illinois Basin). The gray shale containing the upland flora lies directly above the Upper Block Coal (SW 1/4, SE 1/4, sec. 17, T. 11N., R. 6W.)

Two collections, collected on three different occasions were made available for analysis: Smithsonian Natural …


Desorption Hysteresis In Five Ion Exchanged Montmorillonites, Jerry Paul Fairley Jan 1992

Desorption Hysteresis In Five Ion Exchanged Montmorillonites, Jerry Paul Fairley

UNLV Theses, Dissertations, Professional Papers, and Capstones

It is generally believed that the formation of recalcitrant (slowly desorbing) fractions of volatile organic compounds (VOCs) in soils is due to diffusion of compounds to sorption sites inaccessible to bulk fluid. The exact nature of these sites, however, is not well understood. In clay minerals, researchers favor two probable areas for the storage of persistent contamination; sites between the clay lamella, or sites with clay particle aggregates.


To test the hypothesis that recalcitrant fractions are formed in interlamellar spaces, a Na/Ca Montmorillonite (Smectite) was ion exchanged with five different cations (K+, Na+, Ca+, …


Remote Estimation Of The Diffuse Attenuation Coefficient In A Moderately Turbid Estuary, Richard P. Stumpf, Jonathan Pennock Dec 1991

Remote Estimation Of The Diffuse Attenuation Coefficient In A Moderately Turbid Estuary, Richard P. Stumpf, Jonathan Pennock

School of Marine Science and Ocean Engineering

Abstract

Solutions of the radiative transfer equation are used to derive relationships of water reflectance to the diffuse attenuation coefficient (K) in moderately turbid water (K > 0.5 m−1). Data sets collected from the NOAA AVHRR and in situ observations from five different dates confirm the appropriateness of these relationships, in particular the logistic equation. Values of K calculated from the reflectance data agree to within 60% of the observed values, although the reflectance derived using a more comprehensive aerosol correction is sensitive to chlorophyll concentrations greater than 50 μg L−1. Agreement between in situ and remote …


Environmental Radiocesium In Subarctic And Arctic Alaska Following Chernobyl, M. Baskaran, J. J. Kelley, A. S. Naidu, D. F. Holleman Dec 1991

Environmental Radiocesium In Subarctic And Arctic Alaska Following Chernobyl, M. Baskaran, J. J. Kelley, A. S. Naidu, D. F. Holleman

Environmental Science and Geology Faculty Research Publications

Radiocesium (¹³⁴ Cs and ¹³⁷ Cs) concentrations were measured in soil, plant and wildlife samples from subarctic to arctic Alaska. Concentrations of ¹³⁷ Cs ranged from below detectable or low levels in whale and fish samples to as high as 242 Bq/kg in lichen. For all potential human food items, the radiocesium concentrations measured in this study were below accepted permissible levels for human consumption. Chernobyl-derived radiocesium concentrations ranged from below detectable or low levels in all arctic samples (soil, sediment, lichen, whale, fish and caribou) to 32 Bq/kg in subarctic moss. Therefore the distribution and subsequent deposition of Chernobyl-derived …


Biology And Ecology Of Dioryctria Ponderosae Dyar And Dioryctria Tumicolella Mutuura, Munroe And Ross, Mark A. Brohman Dec 1991

Biology And Ecology Of Dioryctria Ponderosae Dyar And Dioryctria Tumicolella Mutuura, Munroe And Ross, Mark A. Brohman

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

No abstract provided.


Biology And Ecology Of Dioryctria Ponderosae Dyar And Dioryctria Tumicolella Mutuura, Munroe And Ross, Mark A. Brohman Dec 1991

Biology And Ecology Of Dioryctria Ponderosae Dyar And Dioryctria Tumicolella Mutuura, Munroe And Ross, Mark A. Brohman

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

No abstract provided.


A Review Of Plant Introductions To The Kimberley 1955 To 1987, R Mccartney Nov 1991

A Review Of Plant Introductions To The Kimberley 1955 To 1987, R Mccartney

Grain and other field crops published reports

This report summarizes the work done by the Department of Agriculture, Western Australia, in the west and north Kimberley in introducing plant species during 1955-1987.

For the purposes of this repor1the following areas are defined thus:

• West Kimberley- lies between latitude 17°5 and 19°5 and longitude 121°E and 127°E, with an extension to the north of 1° between 121°E and I 24°20'E. The area is 118,000 km".

• North Kimberley - lies north of latitude 17°5 and between longitude 124°20'E and 127°30'E. The area is 85,000 km'.

• East Kimberley-lies north of latitude 19°5 and between longitude 127°30'E and …


Earth News, Fall 1991, Department Of Earth Science, University Of Northern Iowa. Oct 1991

Earth News, Fall 1991, Department Of Earth Science, University Of Northern Iowa.

Earth News

Inside this issue:

--- Year in Review
--- Staff News
--- Graduations, Awards, and Recognitions, 1991
--- Department of Earth Science Seminars Spring 1991
--- Department of Earth Science Seminars Fall 1992
--- News from Alumni
--- Seasons Greetings from the Department of Earth Science


Lava-Seawater Interactions At Shallow-Water Submarine Lava Flows, Francis J. Sansone, Joseph A. Resing, Gordon W. Tribble, Peter N. Sedwick, Kevin M. Kelly, Ken Hon Sep 1991

Lava-Seawater Interactions At Shallow-Water Submarine Lava Flows, Francis J. Sansone, Joseph A. Resing, Gordon W. Tribble, Peter N. Sedwick, Kevin M. Kelly, Ken Hon

OES Faculty Publications

Hydrothermal plumes associated with nearshore lava flows from Kilauea Volcano, Hawaii were studied on five occasions during 1989-1990 to address the current lack of data on direct lava-seawater interactions. The following enrichments were found in the sea-surface hydrothermal plumes above the active underwater lava flows: H2, 15,000x ambient seawater concentrations; Mn, 250x; and Si, 20x. Water temperatures reached 46°C. Lower concentrations and temperatures were observed in the plumes with increasing distance from shore, with H2, Si, and Mn concentrations linearly related to seawater temperature. Unlike deep sea spreading center hydrothermal plumes, no CH4 enrichment was …


Threatened And Endanger Species Of Wetiands And Waterways In Iowa, Kansas, Missouri, And Nebraska, Ann Burruss Sep 1991

Threatened And Endanger Species Of Wetiands And Waterways In Iowa, Kansas, Missouri, And Nebraska, Ann Burruss

United States Environmental Protection Agency: Publications

Wetlands and waterways, including perennial and intermittent streams, creeks, and rivers, are habitats for many rare animal and plant species. Wetlands in many areas continue to decline in acreage and suffer adverse impacts from conversion and development. Waterways are also under pressure from channelization and leveeing.

This study has two major components. First, a series of databases was developed that includes animals and plant species that are wetland or waterway dependent and found in Iowa, Kansas, Missouri, or Nebraska. The databases allow ready access to detailed information on each species and probable locations within each state. The plant and animal …


Kinetics And Mechanisms Of Atrazine Adsorption And Desorption In Soils Under No-Till And Conventional Management, V. P. Evangelou, W. W. Witt, E. Portig, Mike Barrett Aug 1991

Kinetics And Mechanisms Of Atrazine Adsorption And Desorption In Soils Under No-Till And Conventional Management, V. P. Evangelou, W. W. Witt, E. Portig, Mike Barrett

KWRRI Research Reports

Both soils (Maury silt loam and Sadler) exhibited three apparent mechanisms of atrazine adsorption. The first two mechanisms were very rapid (10 minutes) and were assigned to soil-clay surface adsorption reactions via hydrogen bonding. The quantity of atrazine involved in these two reactions for the 0.5 mg/1 solution atrazine varied, depending on the soil, from 67 μg/100 g clay to 219 μg/100 g clay. The reason there were two possible atrazine sinks in this range of atrazine adsorption was believed to be the presence of two types of reactive surfaces, the clay inorganic phase and the organic carbon phase. The …