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An Economic Valuation Of The Jandakot Wetlands, Paul Gerrans Jan 1994

An Economic Valuation Of The Jandakot Wetlands, Paul Gerrans

Research outputs pre 2011

Economists implore the efficient allocation of resources. Paradoxically, where the issue of efficiency has become critically important in recent times, namely the allocation of the environment and its resources and amenity, the techniques of economists have been found wanting and less than fully developed. This paper seeks to address this apparent paradox and deficiency.

This paper provides an economic valuation of the Jandakot wetlands, located to the south of Perth. A referendum style contingent valuation method survey is used to estimate economic value attributable to the preservation of wetlands dependant on the groundwater resource. Event history analysis is explored and …


No-Tillage Sowing Decreases Water Erosion On Loamy Soils And Increases Earthworm Activity, Kevin Bligh Jan 1994

No-Tillage Sowing Decreases Water Erosion On Loamy Soils And Increases Earthworm Activity, Kevin Bligh

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

No-tillage sowing places seed and fertiliser in the soil without loosening all of the topsoil. Soil is cultivated only in the sown rows, leaving the inter-row areas largely undisturbed.

No-tillage sowing reduces both wind and water erosion. Soil structure is generally improved, and pasture regeneration is increased because seed is not buried too deeply for re-establishment.

Two long-term trials were establis_hed on loamy soils to determine effects of tillage and cropping on runoff and soil loss.


Using Saltland In Pakistan : An Australian Connection, Ed Barrett-Lennard, Riaz Qureshi Jan 1994

Using Saltland In Pakistan : An Australian Connection, Ed Barrett-Lennard, Riaz Qureshi

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

Pakistan and Australia have a common enemy in salt. In each country millions of hectares of previously productive land have been affected by salt (or have the potential to become saline) because of inappropriate agricultural development. Since 1989 the Western Australian Department of Agriculture has participated in a research project in Pakistan which involves revegetation of salt land using Australian shrubs. Early results are very promising.


Tolerance Of Bitter Compounds By An Herbivore, Cavia Porcellus, Dale L. Nolte, J. Russell Mason, Stanley Lewis Jan 1994

Tolerance Of Bitter Compounds By An Herbivore, Cavia Porcellus, Dale L. Nolte, J. Russell Mason, Stanley Lewis

United States Department of Agriculture Wildlife Services: Staff Publications

Many plant defensive chemicals are bitter to humans. Because of this taste characteristic, and because bitter compounds are often toxic, such substances, and the plants that contain them, are regarded as generally unpalatable to wildlife. These assumptions may be unwarranted. To test the hypothesis that herbivores are indifferent to 'bitter' tastants, we investigated the responsiveness of guinea pigs (Cavia porcellus) to denatonium benzoate, denatonium saccharide, limonene, L-phenylalanine, naringin, quebracho, quinine, Ro-Pel (a commercial animal repellent containing denatonium saccharide) and sucrose octaacetate. Only quinine and sucrose octaacetate slightly but significantly reduced feeding (P < 0.05). Our findings are inconsistent with the notion that herbivores generally avoid what humans describe as bitter tastes.


Stable Isotopes Of Oxygen And Hydrogen In The Truckee River-Pyramid Lake Surface-Water System. 1. Data Analysis And Extraction Of Paleoclimatic Information, Larry Benson Jan 1994

Stable Isotopes Of Oxygen And Hydrogen In The Truckee River-Pyramid Lake Surface-Water System. 1. Data Analysis And Extraction Of Paleoclimatic Information, Larry Benson

United States Geological Survey: Staff Publications

The δ18O content of streamflow discharge entering Pyramid Lake is a simple mixture of isotopically enriched Lake Tahoe discharge and isotopically depleted snowmelt. The δ18O value of Pyramid Lake water varies continuously, as isotopically depleted water evaporates from the epilimnion and isotopically depicted water enters the lake as streamflow discharge and on-lake precipitation. In a normal water year, the δ18O of Pyramid Lake surface water varies seasonally because the components of the hydrologic balance in the Pyramid Lake system are seasonally shifted. The problem of isotopic and thermal heterogeneity can be minimized by analyzing …


Stable Isotopes Of Oxygen And Hydrogen In The Truckee River-Pyramid Lake Surface-Water System, 3: Source Of Water Vapor Overlying Pyramid Lake, Larry Benson, J. W. C. White Jan 1994

Stable Isotopes Of Oxygen And Hydrogen In The Truckee River-Pyramid Lake Surface-Water System, 3: Source Of Water Vapor Overlying Pyramid Lake, Larry Benson, J. W. C. White

United States Geological Survey: Staff Publications

During 1988 and 1989, a series of water-vapor extractions were conducted in the Pyramid Lake basin to determine the source of moisture that overlies the lake. Calculations of the isotopic and water-vapor balances were made from isotopic and meteorological data from the Pyramid Lake and Reno, Nevada, areas. The results indicate that in the warm season, most of the moisture that overlies the lake is derived from evaporation as opposed to advected moisture. Isotopic fluxes at the lake surface can be approximated by climatic data from the lake site, which simplifies the calculation of this input in numerical simulations of …


Identification Of Tire Leachate Toxicants And A Risk Assessment Of Water Quality Effects Using Tire Reefs In Canals, S. M. Nelson, G. Mueller, D. C. Hemphill, U.S. Bureau Of Reclamation Jan 1994

Identification Of Tire Leachate Toxicants And A Risk Assessment Of Water Quality Effects Using Tire Reefs In Canals, S. M. Nelson, G. Mueller, D. C. Hemphill, U.S. Bureau Of Reclamation

Publications (WR)

Cover is an important component of aquatic habitat and fisheries management. Fisheries biologists often try to improve habitats through the addition of natural and artificial material to improve cover diversity and complexity. Habitat-improvement programs range from submerging used Christmas trees to more complex programs using sophisticated artificial habitat modules. Used automobile tires have been employed in the large scale construction of reefs and fish attractors in marine environments and to a lesser extent in freshwater and have been recognized as a durable, inexpensive and long-lasting material which benefits fishery communities.

Recent studies by the U.S. Bureau of Reclamation have quantified …


Base Realignment And Closure - 93: Impacts On Western Aquidneck Island An Opportunity For Enrichment, Frank W. Garcia Jr. Jan 1994

Base Realignment And Closure - 93: Impacts On Western Aquidneck Island An Opportunity For Enrichment, Frank W. Garcia Jr.

Marine Affairs Theses and Major Papers

This paper will develop a conceptual Use/Resource model which may be of use in analyzing coastal zone conflicts. The use/Resource model will be applied to provide an outline for a cooperative enrichment plan for Western Aquidneck Island, Rhode Island. Future studies of Western Aquidneck Island or other coastal communities may be able to use the model to quantify the level of Use/Resource cooperation. Heuristic application of the Model along Western Aquidneck may highlight the level of conflict or cooperation in working towards an enrichment plan. The focus of the enrichment plan will be to improve the quality of life in …


A Preliminary Study Of The Potential For Recycling And Waste Minimisation At Edith Cowan University: Report To The Edith Cowan University Student Guild, Eddie Van Etten, Mark Lund, Robert Troeth Jan 1994

A Preliminary Study Of The Potential For Recycling And Waste Minimisation At Edith Cowan University: Report To The Edith Cowan University Student Guild, Eddie Van Etten, Mark Lund, Robert Troeth

Research outputs pre 2011

In recent years there has been a growing realisation worldwide that disposing of large quantities of waste to landfill was not only causing problems of pollution(e.g. leachate and gas production) but suitable sites were rapidly filling up. In Perth it is has been estimated that present landfill sites will only last until 2007 (Sinclair and Knight, 1991). To help extend the life of current landfill sites and in response to environmental concerns the Western . Australia Government produced a State Recycling Blueprint (Department of Commerce and Trade, 1993). This describes strategies for the minimisation of waste production and maximisation of …


Selecting Controls For Water Distribution Systems, J. Paul Tullis Jan 1994

Selecting Controls For Water Distribution Systems, J. Paul Tullis

Reports

One of the key requirements for reliable operations of a water supply system is a thorough analysis and proper selection of the control valves and pumps. For valves, selection criteria includes capacity, pressure loss, controllability, torque, cavitation and transients. Pump selection requires matching the pump performance to varying system demands. Examples are given for single pump operation and use of pumps in series and parallel. When future demands exceed the original design conditions, or if significant changes are required in the operation of the system, each important control device should be analyzed to see if it can operate safely at …


Antecedent Moisture Conditions For Utah Local Storm Probable Maximum Floods, Travis S. Taylor, David S. Bowles Jan 1994

Antecedent Moisture Conditions For Utah Local Storm Probable Maximum Floods, Travis S. Taylor, David S. Bowles

Reports

Introduction: The critical inflow design flood for most dams in Utah is the probable maximum flood (PMF) resulting from the local storm probable maximum precipitation (PMP) event. Commonly, the Soil Conservation Service (SCS) curve number method is used to determine the PMF from the local storm PMP. An important factor in this determination is the assumption of antecedent moisture conditions (AMC) existing immediately prior to the onset of the PMP event. At one northern Utah dam site the use of AMC III increased the PMF peak flowrate by 50 percent over the peak obtained when AMC II was used (Win …


A Spatially Distributed Energy Balance Snowmelt Model, David G. Tarboton, Tanveer G. Chowdhury, Thomas H. Jackson Jan 1994

A Spatially Distributed Energy Balance Snowmelt Model, David G. Tarboton, Tanveer G. Chowdhury, Thomas H. Jackson

Reports

This paper describes an energy balance snowmelt model developed for the prediction of rapid snowmelt rates responsible for soil erosion and water input to a distributed water balance model. The model uses a lumped representation of the snowpack with two state variables, namely, water equivalent and energy content relative to a reference state of water in the ice phase at 0 degrees Celcius. This energy content is used to determine snowpack average temperature of liquid fraction. This representation of the snowpack is used to determine snowpack average temperature of liquid fraction. This representation of the snowpack is used in a …


Measurements And Modeling Of Snow Energy Balance And Sublimation From Snow, David G. Tarboton Jan 1994

Measurements And Modeling Of Snow Energy Balance And Sublimation From Snow, David G. Tarboton

Reports

Snow melt runoff is an important factor in runoff generation for most Utah rivers and a large contributer to Utah's water supply and periodically flooding. The melting of snow is driven by fluxes of energy into the snow during warm periods. These consist of radiant energy from the sun and atmosphere, sensible and latent heat transfers due to turbulent energy exchanges at the snow surface and a relatively small ground flux from below. The turbulent energy exchanges are also responsible for sublimation from the snow surface, particularly in arid environments, and result in a loss of snow water equivalent available …


The Source Hydrology Of Severe Sustained Drought In Th Southwestern U.S., David G. Tarboton Jan 1994

The Source Hydrology Of Severe Sustained Drought In Th Southwestern U.S., David G. Tarboton

Reports

This paper considers the risk of drought and develops drough scenarios for use in the study of severe sustained drought in the Southwestern United States. The focus is on the Colorado River gbasin and regions to which Colorado River water is exported, especially southern California, which depends on water from the Colorado River as well as the four major rivers in northern California. Drought scenarios are developed using estimates of unimpaired historic streamflow as well as reconstructions of streamflow based on tree ring widths. Drought scenarios in the Colorado River are defined on the basis of annual flow at Lees …


The Study Of Resistance And Stability Of Vegetation In Flood Channels, William Rahmeyer, David Werth, Rob Cleere Jan 1994

The Study Of Resistance And Stability Of Vegetation In Flood Channels, William Rahmeyer, David Werth, Rob Cleere

Reports

Preface: The following report was prepared by the Utah Water Research Laboratory of Utah State University in Logan, Utah. The report contains the data and conclusions of flow tests conducted with different types of shrubs and woody vegetation in the hydraulics flumes of Utah State University. The funding agency for this project was the U.S. Army Engineers Waterwasy Experiment Stations, Vicksburg, MS.; Project Name - Flood Control Channels; Work Unit Title - Stability of Vegetative Cover in Flood Control Channels; Work Unit No - 337A3; Federal Contract No - DACW39-94-K-0009. The study was the result of a proposal submitted in …


Low Frequency Climate Variability: Understanding The Rise And Fall Of The Great Salt Lake, Michael E. Mann, Upmanu Lall, Barry Saltzman Jan 1994

Low Frequency Climate Variability: Understanding The Rise And Fall Of The Great Salt Lake, Michael E. Mann, Upmanu Lall, Barry Saltzman

Reports

Connections between the Great Salt Lake (GSL) volume (V) and large-scale climate variations are developed through an analysis of the time series of the month-to-month differences in V (change in V), local precipitation and streamflow, and gridded U.S. sea level pressure and global temperature data. We isolate decadal and secular mdoes of cliamte variability that are coherent with change in V variations. The decadal variations results from a low-frequency north-south shifting of storm tracks which influence winter precipitation. These variations describe nearly 18% of the interannual variance in change in V, while the secular trend accounts for only ~1.5%. The …


The Great Salt Lake: A Barometer Of Low Frequency Climate Variability, Upmanu Lall, Michael Mann Jan 1994

The Great Salt Lake: A Barometer Of Low Frequency Climate Variability, Upmanu Lall, Michael Mann

Reports

Low frequency (interannual or longer period) climatic variability is of interest bacause of its sugnificance for the understanding and prediction of protracted climatic anomalies. Closed basin lakes are sensitive to long term climatic fluctuations and integrate out high frequency variability. It is thus natural to examine the records of such lakes to better understand long term climate dynamics. Here we use Singular Spectral Analysis (SSA) and Multi-Taper Spectral Analysis (MTM) to analyze the time series of Great Slat Lake (GSL) monthly volume changes from 1848-1992, and monthly precipitation, temperature and streamflow for nearby stations with 74 or more years of …


Utah Water Research Laboratory Publications Listing 1989-1994, David S. Bowles, Leaunda S. Hemphill Jan 1994

Utah Water Research Laboratory Publications Listing 1989-1994, David S. Bowles, Leaunda S. Hemphill

Reports

No abstract provided.


Modeling Daily Production Of Aquatic Macrophytes From Irradiance Measurements: A Comparative Analysis, Richard C. Zimmerman, Alejandro C. Pasini, Randall S. Alberte Jan 1994

Modeling Daily Production Of Aquatic Macrophytes From Irradiance Measurements: A Comparative Analysis, Richard C. Zimmerman, Alejandro C. Pasini, Randall S. Alberte

OES Faculty Publications

The importance of submerged aquatic macrophytes to coastal ecosystems has generated a need for knowledge of minimum light levels that will support the maintenance and restoration of healthy populations. Our goals were (1) to evaluate the sensitivity to natural, non-sinusoidal fluctuations in irradiance I of analytical integration techniques for calculating daily carbon gain, (2) to evaluate the Hsat (the daily period of I-saturated photosynthesis) model of daily production relative to models based on instantaneous photosynthesis vs irradiance (P vs I) and (3) to provide some guidance for the temporal density of irradiance data required for accurate estimation of …


Materials Recovery Facilities In The United States Virgin Islands: A Regional Facilities Location Model Study, Lloyd O. Prince Jr. Jan 1994

Materials Recovery Facilities In The United States Virgin Islands: A Regional Facilities Location Model Study, Lloyd O. Prince Jr.

Engineering Management & Systems Engineering Theses & Dissertations

Continental municipalities have derived many benefits from the economies of scale associated with a regional approach to facilities location and management planning. Centralized solid waste processing facilities is an example. Island communities, however, surrounded by miles of ocean, are constrained to a fragmented approach to the facilities location solution. This research was conducted to determine if the regional paradigm suggested in the literature is applicable to a set of island communities connected by an ocean transportation infrastructure. A linear programming (LP) model, constraints and data requirements were developed and applied to a network of islands. A series of hypothetical material …


Opportunities For Integration In Institutional Arrangements For Water Management In The Yukon, Patrick James Dooling Jan 1994

Opportunities For Integration In Institutional Arrangements For Water Management In The Yukon, Patrick James Dooling

Theses and Dissertations (Comprehensive)

The history of water resources management in the Yukon has been characterized by conflict. This problem is due to the failure to address the interrelationships between water and land resources. Although many parts of the Yukon remain largely undisturbed wilderness areas, development pressures place increasing demands on Territorial water resources. To ensure these stresses do not degrade Yukon waters to the extent common in many Canadian regions, a reevaluation of the legal and administrative arrangements for water management in the Yukon is required. A majority of the legislation pertaining to water management in the Yukon was introduced in the 1970s …


An Ecosystem Approach To Wildlife Management In Wilderness Areas: A Case Study Of The Greater Kluane Region, Lori Katherina Krebs Jan 1994

An Ecosystem Approach To Wildlife Management In Wilderness Areas: A Case Study Of The Greater Kluane Region, Lori Katherina Krebs

Theses and Dissertations (Comprehensive)

This research examines the implications of an ecosystem approach to planning and management for sustainable wildlife populations within a wilderness setting. Kluane National Park Reserve and the surrounding region are the focus of the study, providing a relatively unaltered ecosystem in which to explore certain questions regarding ecosystem-based wildlife management. The ever increasing human population and constant surge of development are placing more and more pressure on remaining natural resources. Wilderness areas and wildlife habitat are disappearing rapidly, and the north is receiving unprecedented activity in the search for remaining resources. Management strategies must be created which will be capable …


The Near-Shore, Soft-Substrate Bivalves Of The Swan Estuary: An Assessment Of Their Use As Biological Indicators, Graham Bailey Jan 1994

The Near-Shore, Soft-Substrate Bivalves Of The Swan Estuary: An Assessment Of Their Use As Biological Indicators, Graham Bailey

Theses : Honours

The soft-substrate bivalves of the Swan Estuary were evaluated for their suitability as biological indicators. The major requirement of a biological indicator is that a response to changing conditions can be shown. Demonstrating that bivalve community and populations respond to changing environmental conditions within The Estuary would fulfill this criteria. To make this assessment the study conducted a quantitative sampling program which established the current structure of the near-shore soft-substrate bivalve community and this was compared with the community established in 1973-74. To evaluate the predictive potential of bivalve structure as an indicator, major environmental conditions in the Estuary were …


Carbon Monoxide In The Antarctic Atmosphere: Observations Of Decreasing Concentrations, M. A. K. Khalil, R. A. Rasmussen Jan 1994

Carbon Monoxide In The Antarctic Atmosphere: Observations Of Decreasing Concentrations, M. A. K. Khalil, R. A. Rasmussen

Environmental Science and Management Faculty Publications and Presentations

Hydroxyl radicals remove hundreds, perhaps thousands, of organic gases from the atmosphere and are often regarded as am index of the oxidizing capacity of the Earth's atmosphere (Thompson 1992). In recent years, there have been growing concerns that, over the past century and now, human activities may be depleting hydroxyl concentrations by adding huge amounts of carbon monoxide and methane to the atmosphere. Reduction in the hydroxyl concentrations can then indirectly lead to more global warming, stratospheric ozone depletion, and other disturbances in atmospheric chemistry. Carbon monoxide (CO) is a key component in the determination of hydroxyl radical (OH) concentrations: …


The Nature And Timing Of Wildlife Damage Events In Nebraska: A Five-Year Review Of Requests To Three Extension Wildlife Personnel, Dale J. Hafer, Scott E. Hygnstrom, Ron J. Johnson, Dennis M. Ferraro Dec 1993

The Nature And Timing Of Wildlife Damage Events In Nebraska: A Five-Year Review Of Requests To Three Extension Wildlife Personnel, Dale J. Hafer, Scott E. Hygnstrom, Ron J. Johnson, Dennis M. Ferraro

Great Plains Wildlife Damage Control Workshop Proceedings

We examined 2,241 telephone calls that were received by 3 University of Nebraska- Cooperative Extension personnel (the 3 junior authors) concerning wildlife damage during 1988-1992. Our objectives were to (1) determine the speciedgroups responsible for most damage-related telephone calls, (2) determine the timing of wildlife damage events by speciedgroup, and (3) differentiate damage-related telephone calls by urban versus rural situations.


Twenty-Five Year History Of The Kansas Coyote Damage Control Program, F. Robert Henderson Dec 1993

Twenty-Five Year History Of The Kansas Coyote Damage Control Program, F. Robert Henderson

Great Plains Wildlife Damage Control Workshop Proceedings

In the 1968 legislative session, an appropriate was made to Kansas State University to hire a predator and rodent control specialist. I was hired for this position on July 1, 1968. During August, 1968, I traveled to Missouri and spent a week working with Mr. Bob Smith, a long-time employee of the Missouri Conservation Department's Extension-Trapper program. He taught me how to teach people to trap coyotes.


State Program In Sotuh Dakota For Wildlife Damge Management, Emmett J. Keyser Dec 1993

State Program In Sotuh Dakota For Wildlife Damge Management, Emmett J. Keyser

Great Plains Wildlife Damage Control Workshop Proceedings

In recent years, wildlife professionals have become increasingly more convinced that wildlife-damage programs must be integrated into existing wildlife management structures if both are to succeed in their missions. South Dakota has managed a state-run Animal Damage Control Program through the Department of Game, Fish and Parks since 1974.


Rejex-It'" Ag-36 The Gentle Way To Repel Geese From Golf Courses And Other Turf Areas, Peter F. Vogt Dec 1993

Rejex-It'" Ag-36 The Gentle Way To Repel Geese From Golf Courses And Other Turf Areas, Peter F. Vogt

Great Plains Wildlife Damage Control Workshop Proceedings

Birds have always been a problem in agriculture, specially for berries and fruits. Farmers and home owners have been fighting these problems with limited success for centuries. However, the problems with birds on turf are relatively new and are not even known by many people. The "Complete Guide to Pest Control" (Ware 1988) does not even mention geese as a pest, or golf courses as an area of bird problems.


Utah State University's Berryman Institute For Wildlife Damage Management, Robert H. Schmidt, Michael R. Conover Dec 1993

Utah State University's Berryman Institute For Wildlife Damage Management, Robert H. Schmidt, Michael R. Conover

Great Plains Wildlife Damage Control Workshop Proceedings

In 1990, the College of Natural Resources at Utah State University established a program dedicated to research, education, and extension in wildlife damage management (Schmidt et al. 1992a). This program was initiated with funding from the U. S. Department of Agriculture, Animal and Plant Health Inspection Service, Animal Damage Control (ADC) program and Utah State University.


Pred-X Field Test Results, R.A. Field, J.E. Nel Dec 1993

Pred-X Field Test Results, R.A. Field, J.E. Nel

Great Plains Wildlife Damage Control Workshop Proceedings

During the spring and summer of 1992, a number of sheep producers used Pred-X ear tags to guard against predation by coyotes. We were able to contact 20 of these producers through the help of the Wyoming Wool Growers Association, county agents and companies who sold the tags. Sheep producers in other states also used the tags and we were able to contact 21 of these producers through the cooperation of the American Sheep Industry Association whose representatives printed a short letter and a survey form in the October 1992 National Wool Grower Magazine. Phone calls were made to many …