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Full-Text Articles in Natural Resources Management and Policy

Nutrient Limitation In A Southwestern Desert Reservoir: Eutrophication Of Las Vegas Bay, Lake Mead, Nevada, Davine M. Lieberman Sep 1995

Nutrient Limitation In A Southwestern Desert Reservoir: Eutrophication Of Las Vegas Bay, Lake Mead, Nevada, Davine M. Lieberman

Publications (WR)

Algal bioassay tests were conducted with Selenastrum capricornutum and natural algae on inner Las Vegas Bay, Lake Mead, Nevada, from December 1992 through September 1993, to identify any nutrient limitation in an area of the reservoir that has experienced problems associated with severe nutrient enrichment. Three areas were sampled based on a gradient of water quality conditions that existed in Las Vegas Bay (LVB). Disodium ethylenedinitrilotetraacetate (EDTA) significantly stimulated algal growth compared to non-EDTA treatment. Algal bioassays indicated that phosphorus (P) was the primary limiting nutrient at all stations for most of the test dates. Chl a response with EDTA …


Ecological Risk Assessment For Chemical Stressors: Challenges In Predictive Ecotoxicology Research, Steven P. Bradbury Jan 1995

Ecological Risk Assessment For Chemical Stressors: Challenges In Predictive Ecotoxicology Research, Steven P. Bradbury

Steven P. Bradbury

Environmental management decisions are increasingly based on the results of ecological risk assessments that require data and models to establish the likelihood of adverse ecological effects that may occur or are occurring as a result of exposure to one or more stressors .. Research to support ecological risk assessments for chemical stressors must include a predictive capability.. The great number of chemicals, species and habitats (exposure conditions) associated with prospective and retrospective management decisions precludes the use of empirical testing as the sole means to fill data gaps .. Therefore, strategic laboratory and field testing must be undertaken in the …


Sar Models For Futile Metabolism: One-Electron Reduction Of Quinones, Phenols And Nitrobenzenes, Steven P. Bradbury, Ovanes Mekenyan, G. D. Veith, N. Zaharieva Jan 1995

Sar Models For Futile Metabolism: One-Electron Reduction Of Quinones, Phenols And Nitrobenzenes, Steven P. Bradbury, Ovanes Mekenyan, G. D. Veith, N. Zaharieva

Steven P. Bradbury

Benzoquinones, naphthoquinones and aziridinylbenzoquinones, can be reduced by flavoproteins to semiquinones that react with molecular oxygen to form superoxide anion with the subsequent regeneration of the parent compounds. This redox cycling, a form of futile metabolism, produces reactive oxygen species and depletes the reducing equivalents of cells without concomitant energy production. The ability of a toxicant to redox cycle is related to its one-electron reduction potential, and this study attempted to estimate reduction potential from structure using semi-empirical quantum chemical models for a diverse set of chemicals. The results of this study suggest that one-electron reduction potentials, within structural classes …


Quantitative Structure-Activity Relationships And Ecological Risk Assessment: An Overview Of Predictive Aquatic Toxicology Research, Steven P. Bradbury Jan 1995

Quantitative Structure-Activity Relationships And Ecological Risk Assessment: An Overview Of Predictive Aquatic Toxicology Research, Steven P. Bradbury

Steven P. Bradbury

In the field of aquatic toxicology, quantitative structure-activity relationships (QSARs) have developed as scientifically credible tools for predicting the toxicity of chemicals when little or no empirical data are available. A fundamental understanding of toxicological principles has been considered an important component to the acceptance and application of QSAR approaches as biologically relevant in ecological risk assessments. As a consequence, there has been an evolution of QSAR development and application from that of a chemical-class perspective to one that is more consistent with assumptions regarding modes of toxic action. In this review, techniques to assess modes of toxic action from …


Use Of Knowledge Bases And Qsars To Estimate The Relative Ecological Risk Of Agrichemicals: A Problem Formulation Exercise, Steven P. Bradbury, C. L. Russom, A. R. Carlson Jan 1995

Use Of Knowledge Bases And Qsars To Estimate The Relative Ecological Risk Of Agrichemicals: A Problem Formulation Exercise, Steven P. Bradbury, C. L. Russom, A. R. Carlson

Steven P. Bradbury

Ecological risk assessments can be used to establish the likelihood that an adverse effect will result from exposure to one or more chemicals. When evaluating contaminated sites with many chemicals present, risk assessors must grapple with the problem of quickly identifying the chemicals that are most likely to be of concern, based on effect and exposure assessment information. Many times data gaps exist and the risk assessor is left with decisions on which models to use to estimate the parameter of concern. In the present paper, a procedure is presented for ranking agrichemicals, utilizing the ASTER (ASsessment Tools for the …


Remnant Vegetation Inventory On The Southern Agricultural Areas Of Western Australia., G R. Beeston, G Mlodowski, A Sanders, D True Jan 1995

Remnant Vegetation Inventory On The Southern Agricultural Areas Of Western Australia., G R. Beeston, G Mlodowski, A Sanders, D True

Resource management technical reports

Remnant vegetation mapping and its incorporation into a Geographical Information System (GIS) data base is the first stage in an overall documentation and promotion of conservation of remnant vegetation in Western Australia. The primary objective of this project being to determine the amount, distribution and regional location of native vegetation remaining on private land in the agricultural area of south-west Western Australia.


Reading The Rangeland: A Guide To The Arid Shrublands Of Western Australia, Don Burnside, Alec Holm, Alan Payne, Georgina Wilson Jan 1995

Reading The Rangeland: A Guide To The Arid Shrublands Of Western Australia, Don Burnside, Alec Holm, Alan Payne, Georgina Wilson

All other publications

Managing the rangelands is complex. Soils and vegetation can vary considerably over short distances in distinct or subtle ways. Separating climatic from management influences on the condition of the land has always been difficult. Whether we live on a sheep station, in a country town, in an Aboriginal community, a mining camp, or even if we only visit the Australian outback, it is vital that we understand and appreciate the unique character and management requirements of the rangelands. Learning to ‘read the rangeland’ has been a slow process, involving the knowledge and skills of pastoralists, Aboriginal people and scientists. This …


Risk Assessment Plan For Petroleum Underground Storage Tanks In Kentucky, Wesley J. Birge, L. C. Taylor, M. D. Kircher, A. J. Grant Jan 1995

Risk Assessment Plan For Petroleum Underground Storage Tanks In Kentucky, Wesley J. Birge, L. C. Taylor, M. D. Kircher, A. J. Grant

KWRRI Research Reports

This study addresses the development of guidelines for corrective actions to be applied to petroleum underground storage tanks (USTs) within the Commonwealth of Kentucky. The report presents findings and recommendations for gasoline, diesel fuel, heating oil, kerosene, jet fuel, and waste oil.