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Earth Sciences

1998

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Full-Text Articles in Life Sciences

New Caribbean Locality For The Extinct Great White Shark Carcharodon, Clare Flemming, Donald A. Mcfarlane Dec 1998

New Caribbean Locality For The Extinct Great White Shark Carcharodon, Clare Flemming, Donald A. Mcfarlane

WM Keck Science Faculty Papers

Carcharodon is represented by a single upper tooth (Fig. 1) which we extracted from the eroding Pliocene limestone wall, some six meters above the floor at the northern end of Darby Sink. Much of the tooth is missing, but the remaining portion includes features diagnostic of this genus. The tooth conforms in size and morphology to Carcharodon megalodon (Agassiz, 1843), an extinct great white shark.


A Second Pre-Wisconsinan Locality For The Extinct Jamaican Rodent, Clidomys (Rodentia: Heptaxodontidae), Donald A. Mcfarlane, Joyce Lundberg, Clare Flemming, Ross D. E. Macphee, Stein-Erik Lauritzen Dec 1998

A Second Pre-Wisconsinan Locality For The Extinct Jamaican Rodent, Clidomys (Rodentia: Heptaxodontidae), Donald A. Mcfarlane, Joyce Lundberg, Clare Flemming, Ross D. E. Macphee, Stein-Erik Lauritzen

WM Keck Science Faculty Papers

Clidomys is the most distinctive but least well known member of the late Quaternary terrestrial mammal fauna of Jamaica. Here we report the second dated locality for this genus. The Illinoisan age we report further strengthens arguments we have made elsewhere, that Clidomys represents an early - probably pre-Wisconsinan - extinction that contrasts with the growing record of Holocene extinctions in the Antilles.


Observations On Groundwater Recharge In The Westdale Catchment, M F. Lewis, C E. Mcconnell Dec 1998

Observations On Groundwater Recharge In The Westdale Catchment, M F. Lewis, C E. Mcconnell

Resource management technical reports

A study of the role of groundwater carriers and barriers in controlling salinity was carried out in the Westdale Catchment by Lewis and McConnell (in preparation). Although that study was primarily concerned with groundwater flow and discharge processes, the data collected also provided rudimentary information on the timing of groundwater recharge events and their distribution across the landscape.


Comparison Of Water And Temperature Distribution Profiles Under Sand Tube Irrigation, Masoud Meshkat, Richard C. Warner, Stephen R. Workman Nov 1998

Comparison Of Water And Temperature Distribution Profiles Under Sand Tube Irrigation, Masoud Meshkat, Richard C. Warner, Stephen R. Workman

Biosystems and Agricultural Engineering Faculty Publications

Drip irrigation is one of the most efficient systems in delivering water to the plant root zone. Research has shown that the saturated, or nearly saturated, surface beneath the emitter may increase evaporation thereby reducing the irrigation efficiency. To increase the efficiency of surface applied drip irrigation on permanent tree crops a sand tube irrigation (STI) method was developed and tested. The sand tube method consists of removing a soil core beneath the emitter and filling the void with coarse sand. A weighing lysimeter was designed and instrumented to directly measure temporal evaporation during irrigation and for a period of …


Field Scale Variability Of Nitrogen And Δ15n In Soil And Plants, D. E. Clay, J. Chang, S. A. Clay, M. Ellsbury, C. G. Carlson, D. D. Malo, D. Woodson, T. Desttur Nov 1998

Field Scale Variability Of Nitrogen And Δ15n In Soil And Plants, D. E. Clay, J. Chang, S. A. Clay, M. Ellsbury, C. G. Carlson, D. D. Malo, D. Woodson, T. Desttur

Agronomy, Horticulture and Plant Science Faculty Publications

Understanding the factors that influence soil and plant nitrogen (N) spatial variability may improve our ability to develop management systems that maximize productivity and minimize environmental hazards. The objective of this study was to determine the field (65 ha) scale spatial variability of N and δ15N in soil and corn (Zea mays). Soil, grain, and stover samples were collected from grids that ranged in size from 30 by 30 m to 60 by 60 m. Plant samples, collected following physiological maturity in 1995, were analyzed for total N and δ15N. Soil samples, collected prior …


Revegetation Strategies For Groundwater Control In The Eastern Wheatbelt, C E. Mcconnell Oct 1998

Revegetation Strategies For Groundwater Control In The Eastern Wheatbelt, C E. Mcconnell

Resource management technical reports

No abstract provided.


Agricultural Water Management In The Missippi Delta Region Of Arkansas, H. Don Scott, James A. Ferguson, Linda Hanson, Todd Fugitt, Earl Smith Aug 1998

Agricultural Water Management In The Missippi Delta Region Of Arkansas, H. Don Scott, James A. Ferguson, Linda Hanson, Todd Fugitt, Earl Smith

Research Reports and Research Bulletins

Agriculture is the largest use of soil and water resources in eastern Arkansas. This bulletin summarized the recent historical use of soil and water by agriculture and the impact of irrigation on yields of rice, soybeans and cotton. The experiments conducted in the field to quantitatively schedule irrigations of crops are summarized. The results show the close relationship between the irrigation of crops and the extraction of water from the Alluvial Aquifer. The implications of this relationaship for the future are discussed.


Quality Of Runoff From Plots Treated With Municipal Sludge And Horse Bedding, Elizabeth L. Busheé, Dwayne R. Edwards, Philip A. Moore Jr. Jul 1998

Quality Of Runoff From Plots Treated With Municipal Sludge And Horse Bedding, Elizabeth L. Busheé, Dwayne R. Edwards, Philip A. Moore Jr.

Biosystems and Agricultural Engineering Faculty Publications

Land application of horse stall bedding and municipal sludge can increase runoff concentrations of nutrients, organic matter, and bacteria as well as steroidal hormones such as estrogen. Concentrations of materials in runoff from sites treated with animal manure can be reduced by aluminum sulfate, or alum [Al2(SO4)3•14H2O] treatment. The objectives of this study were to assess plots treated with horse stall bedding or municipal sludge for: (a) runoff quality [concentrations of nitrate nitrogen (NO3-N), ammonia nitrogen (NH3-N), orthophosphate-phosphorus (PO4-P), fecal coliform (FC), chemical oxygen demand (COD) …


Results Of Investigations Into The Groundwater Response And Productivity Of High Water Use Agricultural Systems 1990-1997 1. Wooldridge/Wright's Catchment (Kojonup), A D. Smith, Richard J. George Dr, P R. Scott, D L. Bennett, R J. Rippon, G J. Orr Jul 1998

Results Of Investigations Into The Groundwater Response And Productivity Of High Water Use Agricultural Systems 1990-1997 1. Wooldridge/Wright's Catchment (Kojonup), A D. Smith, Richard J. George Dr, P R. Scott, D L. Bennett, R J. Rippon, G J. Orr

Resource management technical reports

High water use vegetation systems for salinity control were trialed on a 170 ha catchment located 13 km north of Kojonup, Western Australia. The catchment receives about 470 mm annual rainfall and 1825 mm annual evaporation.


Results Of Investigations Into The Groundwater Response And Productivity Of High Water Use Agricultural Systems 1990-1997. 2. Souths' Catchment (Darkan), A D. Smith, Richard J. George Dr, P R. Scott, D L. Bennett, R J. Rippon, G J. Orr Jul 1998

Results Of Investigations Into The Groundwater Response And Productivity Of High Water Use Agricultural Systems 1990-1997. 2. Souths' Catchment (Darkan), A D. Smith, Richard J. George Dr, P R. Scott, D L. Bennett, R J. Rippon, G J. Orr

Resource management technical reports

High water use vegetation systems for salinity control were trialed on a 90 ha catchment located 12 km north north-west of Darkan, Western Australia. The catchment receives about 560 mm annual rainfall and 1895 mm annual evaporation. The catchment is characterised by a number of actively expanding seeps which are developing under the strong geological control of quartz and dolerite dykes. Development of salinity is also influenced by high recharge rates in the free draining gravel soils of the upper slope.


Air-Water Gas Exchange And The Carbon Cycle Of Green Bay, Lake Michigan, James Waples May 1998

Air-Water Gas Exchange And The Carbon Cycle Of Green Bay, Lake Michigan, James Waples

Theses and Dissertations

The purpose of this study was to constrain estimates of the kinetics of gas transfer across the air-water interface as well as quantify the net flux of carbon between southern Green Bay (1635 km2) and the atmosphere.

In 1994 and 1995, over 3500 measurements of surface water CH4 and CO2 were made using a continuous sample disk equilibrator. Estimates of CH4 flux from southern Green Bay to the atmosphere based on air-water concentration gradients, shear corrected wind speeds and the U/K (wind speed/transfer coefficient) relationship of Broecker et al. (1978) agreed to within ~10% of …


Utilization Of Spatially Distributed Soil Resources By Several Species Common To The Great Basin, Sarah Duke May 1998

Utilization Of Spatially Distributed Soil Resources By Several Species Common To The Great Basin, Sarah Duke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Heterogeneous spatial and temporal distributions of soil resources important to plant growth have been documented in the sagebrush steppe ecosystem. There can exist as much variability in soil resources within the root zone of individual plants as exists across an entire field. The objective of this dissertation research was to evaluate how plants respond to, utilize and influence the spatial heterogeneity of soil resources. The three specific sets of questions addressed are outlined in the three main chapters of this dissertation.

My first study addressed how the number and concentration of phosphorus (P) patches in the root zone of an …


Arkansas Soil Fertility Studies 1997, Wayne E. Sabbe Apr 1998

Arkansas Soil Fertility Studies 1997, Wayne E. Sabbe

Arkansas Agricultural Experiment Station Research Series

No abstract provided.


The Age Of The Kirkdale Cave Palaeofauna, Donald A. Mcfarlane, Derek C. Ford Apr 1998

The Age Of The Kirkdale Cave Palaeofauna, Donald A. Mcfarlane, Derek C. Ford

WM Keck Science Faculty Papers

The Kirkdale Cave palaeofauna represents the original and classic 'warm', interglacial mammalian cave deposit in Britain. Although long considered to be 'Ipswichian' in age, no previous attempts to obtain radiometric dates have been recorded. Here we report a uranium-series disequilibrium date of 121,000 ± 4000 yr BP on a flowstone capping that overlay the original bone bed. The precision of the date exceeds that obtained at any other British Interglacial cave site, and permits tentative correlation with the high precision ice core records now available.


Groundwater Trends In The Agricultural Area Of Western Australia, R A. Nulsen Mar 1998

Groundwater Trends In The Agricultural Area Of Western Australia, R A. Nulsen

Resource management technical reports

In 1994 it was estimated that salinity affected more than 1.8 million ha of agricultural land in Western Australia (Ferdowsian et al. 1996). This area was predicted to expand to over three million ha by about 2020 and, if nothing is done to stem the expansion, to eventually affect some six million ha, or 30% of the agricultural land in the state. Damaging levels of salt accumulation in the root zone of both native and introduced plants can generally only occur when the groundwater levels are relatively cl te the variability of responses. Several depict episodic recharge (recharge as a …


Environmental Management For Animal-Based Industries : Dairy Farm Effluent, Western Australia Agriculture Western Australia Bunbury Regional Office., Dairy Industry Nutrient Strategy Working Group (W.A.) Feb 1998

Environmental Management For Animal-Based Industries : Dairy Farm Effluent, Western Australia Agriculture Western Australia Bunbury Regional Office., Dairy Industry Nutrient Strategy Working Group (W.A.)

Bulletins 4000 -

The effluent which collects around dairies and their associated feeding facilities should be regarded as a resource to be retained and used on the farm, rather than a waste product for disposal.

These guidelines aim to assist dairy farmers plan effluent management systems which are practical, as well as easy to install and manage, while also being acceptable to the agencies and authorities given the responsibility of protecting the environment. .


Planning To Grow Vegetables Commercially, John Burt, Peter Gartrell Jan 1998

Planning To Grow Vegetables Commercially, John Burt, Peter Gartrell

Bulletins 4000 -

This Bulletin was developed by Department of Agriculture in recognition of the increasing complexity and competitiveness in establishing a commercial vegetable enterprise. The information in this Bulletin will provide you with a useful guide to assess your likelihood of succeeding in vegetable production.

Vegetable production is not an easy lifestyle. It is a highly competitive environment with the industry consisting of growers with big investments and years of experience and knowledge. Horticultural farms require a large amount of capital and time and are increasingly expanding and becoming more specialised.

If you are serious about growing vegetables, work through this Bulletin …


An Inventory And Condition Survey Of The Sandstone-Yalgoo-Paynes Find Area, Western Australia, A L. Payne, A M E Van Vreeswyk, K A. Leighton, H J. Pringle, P Hennig Jan 1998

An Inventory And Condition Survey Of The Sandstone-Yalgoo-Paynes Find Area, Western Australia, A L. Payne, A M E Van Vreeswyk, K A. Leighton, H J. Pringle, P Hennig

Technical Bulletins

The inventory and condition survey of the Sandstone-Yalgoo-Paynes Find area, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 1992 and 1993, describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the area’s natural resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The area surveyed covers about …


Success With Serradella In The Wheatbelt, Clinton Revell, Bradley Nutt, Michael Ewing Jan 1998

Success With Serradella In The Wheatbelt, Clinton Revell, Bradley Nutt, Michael Ewing

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

Clinton Revell, Bradley Nutt, and Michael Ewing review the latest developments with new varieties of French serradella and yellow seradella that should provide the basis for productive legume pastures on acidic, sandy soils throughout the wheatbelt of Western Australia


Validating A Vegetative Filter Strip Performance Model, Puneet Srivastava, Thomas A. Costello, Dwayne R. Edwards, James A. Ferguson Jan 1998

Validating A Vegetative Filter Strip Performance Model, Puneet Srivastava, Thomas A. Costello, Dwayne R. Edwards, James A. Ferguson

Biosystems and Agricultural Engineering Faculty Publications

Vegetative filter strips (VFS) reduce losses of nutrients, solids, and other materials from land area treated with fertilizers and manures. A number of models are available that simulate nutrient and sediment transport in VFS. While VFS effectiveness is considered to depend on lengths of pollutant source area and VFS areas, few published studies have tried to validate these models using variable pollutant source area and VFS area. The objective of this study was to validate an event-based nutrient transport model (Chaubey et al., 1995) that simulates soluble nutrient transport in VFS. This model links three sub-models: modified Green-Ampt infiltration, non-linear …


Western Australia Soil Acidity Research And Development Update 1998 : Time To Lime, Department Of Agriculture And Food, Western Australia Jan 1998

Western Australia Soil Acidity Research And Development Update 1998 : Time To Lime, Department Of Agriculture And Food, Western Australia

Bulletins 4000 -

Recent yield responses by canola where lime has been applied to acidic soils are very encouraging. Two sites have shown that the yield increase in canola after lime was applied in the previous year would have easily paid for the total cost of purchase, transport and application of the lime.

This work was carried out to demonstrate the increased options that are likely to be available once producers are treating or managing soil acidity. Canola is becoming increasingly important as a cash value crop and a break crop allowing wider rotations.

Growers are pushing the limits of canola’s tolerance to …


Environmental And Botanical Controls On Peatification - A Comparative Study Of Two New Zealand Restiad Bogs Using Py-Gc/Ms, Petrography And Fungal Analysis, Tomasz K. Kuder, Michael A. Kruge, J C. Shearer, S L. Miller Jan 1998

Environmental And Botanical Controls On Peatification - A Comparative Study Of Two New Zealand Restiad Bogs Using Py-Gc/Ms, Petrography And Fungal Analysis, Tomasz K. Kuder, Michael A. Kruge, J C. Shearer, S L. Miller

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

This study shows that chemical properties of two restiad species, Empodisma minus and Sporadanthus traversii, may contribute to their success as peat-formers in a climate of the North Island of New Zealand which is not conducive to raised mire development. Unlike Sphagnum, the equivalent northern hemisphere peat-former, restiads possess lignin in their tissues. In addition, the presence of non-lignin polyphenols (including tannins and phenolic acids) in restiads may be an important factor in peat formation due to the allelopathic decay retardation. Patterns of degradation of plant biopolymers have been examined and the pathway of degradation of monocotyledons (loss …


Resource Use In The Trinational Sangha River Region Of Equatorial Africa: Histories, Knowledge Forms, And Institutions, Heather E. Eves, Rebecca Hardin, Stephanie Rupp Jan 1998

Resource Use In The Trinational Sangha River Region Of Equatorial Africa: Histories, Knowledge Forms, And Institutions, Heather E. Eves, Rebecca Hardin, Stephanie Rupp

Yale School of the Environment Bulletin Series

This volume is based on an international conference, “Natural Resource Use Relations in the Trinational Sangha River Region of the Northwest Congo Basin,” held at Yale University in September 1997. In recognition of the bilingual context in which conservation occurs in the three countries of the Sangha region — Cameroon, Central African Republic, and Congo — all sessions of the conference were conducted simultaneously in French and English. This publication, which is a complete rendering of the conference papers and discussion sessions, is available in its entirety in both French and English.


Magnetostratigraphy Of Cueva Del Aleman, Isla De Mona, Puerto Rico And The Species Duration Of Audobon's Shearwater, Bruce C. Panuska, John M. Mylroie, Darrell Armentrout, Donald A. Mcfarlane Jan 1998

Magnetostratigraphy Of Cueva Del Aleman, Isla De Mona, Puerto Rico And The Species Duration Of Audobon's Shearwater, Bruce C. Panuska, John M. Mylroie, Darrell Armentrout, Donald A. Mcfarlane

WM Keck Science Faculty Papers

Magnetostratigraphic analysis of deposits exposed in Cueva del Aleman shows two reversed and two normal chronozones. The lower normal polarity event is observed in a clastic dike and probably predates initial cave formation. Sediments deposited inside the cave proper show a R-N-R sequence and probably date to at least 1.8 Ma. A fossiliferous clastic dike contains normal polarity with an overlying reversed magnetozone. Audubon’s Shearwater (bird) bones occur in the dike, which is tentatively correlated with the lower N polarity zone predating cave formation. If this correlation is correct, the Audubon’s Shearwater (Puffinus lherminieri) range can be extended back to …


Morphology And Process On The Lateritic Coastline Near Darwin, Northern Australia, R. W. Young, Edward A. Bryant Jan 1998

Morphology And Process On The Lateritic Coastline Near Darwin, Northern Australia, R. W. Young, Edward A. Bryant

Faculty of Science - Papers (Archive)

Coastal morphology near Darwin is controlled mainly by the gentle warping of a lateritic profile. In synclines the lateritic cuirasse forms extensive shore platforms, but on the anticlines the pallid zone of the weathering profile is eroded by waves, causing the undercut cuirasse to collapse. The dominant modern process on the shore platforms is solutional attack on the laterite, resulting in large depressions. Many of the platforms are covered by relict layers of cemented laterite cobbles transported by waves of high energy. C14 ages on carbonate cement between the cobbles show that one sheet was deposited at about 3700 BP …


Results Of Investigations Into The Groundwater Response And Productivity Of High Water Use Agricultural Systems 1990-1997 5 White/Beattys' Catchment (Dinninup), A D. Smith, Richard J. George Dr, P R. Scott, D L. Bennett, R J. Rippon, G J. Orr Jan 1998

Results Of Investigations Into The Groundwater Response And Productivity Of High Water Use Agricultural Systems 1990-1997 5 White/Beattys' Catchment (Dinninup), A D. Smith, Richard J. George Dr, P R. Scott, D L. Bennett, R J. Rippon, G J. Orr

Resource management technical reports

High water use vegetation systems for salinity control were trialed on a 250 ha catchment located three km north-west of Dinninup, Western Australia. The catchment receives about 620 mm annual rainfall and 1500 mm annual evaporation. The catchment is characterised by slopes with gradients in excess of 5%, deep weathering (15-25 m to bedrock), active seepage in the valley (piezometric heads 204 m above ground surface) and high recharge (water table fluctuations of 1-4 m).


Iron In Ice Cores From Law Dome, East Antarctica: Implications For Past Deposition Of Aerosol Iron, R. Edwards, Peter N. Sedwick, Vin Morgan, C. F. Boutron, S. Hong Jan 1998

Iron In Ice Cores From Law Dome, East Antarctica: Implications For Past Deposition Of Aerosol Iron, R. Edwards, Peter N. Sedwick, Vin Morgan, C. F. Boutron, S. Hong

OES Faculty Publications

Total-dissolvable iron has been measured in sections of three ice cores from Law Dome, East Antarctica, and the results used to calculate atmospheric iron deposition over this region during the late Holocene and to provide a preliminary est. of aerosol iron deposition during the Last Glacial Maximum (LGM). Ice-core sections dating from 56-2730 BP (late Holocene) and ∼18 000 BP (LGM) were decontaminated using trace-metal clean techniques, and total-dissolvable iron was determined in the acidified meltwaters by flow-injection analysis. Our results suggest that the atmospheric iron flux onto the Law Dome region has varied significantly over time-scales ranging from seasonal …


Amphicyonidae, Robert Hunt Jan 1998

Amphicyonidae, Robert Hunt

University of Nebraska State Museum: Mammalogy Papers

The Amphicyonidae occur in North America from late Eocene (~40 Ma) to early late Miocene (~9 Ma), a span of 31 million years. In the North American land mammal biochronology, this diverse family extends from the Duchesnean to the end of the Clarendonian and is especially well represented in the Miocene (~5-24 Ma). In the Old World, amphicyonids survive no longer than in North America: The last European records are Vallesian (Dinotheriensande, Mainz Basin, Germany, Kuss, 1965, Tobien, 1980; Vallés-Penédes Basin, Spain, Crusafont-Pairó and Kurten, 1976), and the last representative may occur at about 9 Ma at Kohfidisch, Austria (latest …


The Biogeochemical Cycling Of Dissolved Organic Nitrogen In Estuarine Sediments, David J. Burdige, Shilong Zheng Jan 1998

The Biogeochemical Cycling Of Dissolved Organic Nitrogen In Estuarine Sediments, David J. Burdige, Shilong Zheng

OES Faculty Publications

Benthic fluxes and pore-water profiles of dissolved organic nitrogen and carbon (DON and DOC, respectively) were determined in seasonal studies at contrasting sites in Chesapeake Bay. Pore-water dissolved organic matter (DOM) concentrations were elevated over bottom-water values, generally increased with depth, and ranged from 15 to similar to 160 μM for DON and ~200-2000 μM for DOC. Pore-water DOM concentrations and the C:N ratio of this material showed spatial (depth) and temporal changes that varied among the sites studied. These trends appeared to be related to differences in the types of sediment organic matter (SOM) undergoing remineralization, as well as …


Phosphorus In The Landscape: Diffuse Sources To Surface Waters. Land And Water Resources Research And Development Corporation. Occasional Paper 16/98, Richard Davis, Anne Hamblin, E O'Loughlin, Nic Austin, R Banens, P Cornish, P Hairsin, M Mcculloch, Phil Moody, J Olley, B Prove, I Smalls, David Weaver Jan 1998

Phosphorus In The Landscape: Diffuse Sources To Surface Waters. Land And Water Resources Research And Development Corporation. Occasional Paper 16/98, Richard Davis, Anne Hamblin, E O'Loughlin, Nic Austin, R Banens, P Cornish, P Hairsin, M Mcculloch, Phil Moody, J Olley, B Prove, I Smalls, David Weaver

All other publications

The National Eutrophication Management Program (NEMP) and Environment Australia convened a workshop to develop a coherent overview of the sources and transport of diffuse phosphorus in Australian catchments based on the latest knowledge. The Land and Water Resources Research and Development Corporation (LWRRDC) and the Murray–Darling Basin Commission (MDBC) jointly fund NEMP. A select group of scientists attended the workshop and developed a coherent statement about phosphorus sources and transport in Australian catchments. The group did not extend this statement to include recommended management practices. This paper reports the findings from the workshop. State governments have developed algal and nutrient …