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Mammut Borsoni (Hays 1834) From The Early Pliocene Of Husnicioara (Mehedinţi District, Romania), Vlad Codrea, Florina Diaconu Feb 2008

Mammut Borsoni (Hays 1834) From The Early Pliocene Of Husnicioara (Mehedinţi District, Romania), Vlad Codrea, Florina Diaconu

Studia UBB Geologia

A mastodon tooth has been found at Husnicioara coal open pit, in Mehedinţi district (southwestern Romania). It originates from the Lower Pliocene (Dacian) gravel and sand deposits lying just above the coal bed IV, mined in this quarry. The tooth exposing zygodont features undoubtedly belongs to Mammut borsoni (“Borson’s mastodont”). Although this species is very common in the Pliocene vertebrate faunas from this part of Europe, until now it was missing from the Lower Pliocene (Dacian) assemblage’s lists in our country.


Improving Predicted Distribution Models For Riverine Species: An Example From Nebraska, Scott P. Sowa, Gust Annis, Michael E. Morey, A. Garringer Feb 2008

Improving Predicted Distribution Models For Riverine Species: An Example From Nebraska, Scott P. Sowa, Gust Annis, Michael E. Morey, A. Garringer

United States Geological Survey: Publications

Modeling species distributions is in most instances, we believe, better if perceived as an exercise in modeling spatial patterns in habitat conditions. This perspective forces the modeler to think about factors and processes that influence local habitat and also to account for as many of these factors as possible in the modeling process. Local habitat conditions in riverine ecosystems (for example, pH, temperature, turbidity, permanence of flow, depths, velocities, substrate, cover, primary production, etc.) are influenced by a wide array of factors and processes operating at multiple spatial and temporal scales (Matthews 1998; Fausch et al. 2002). However, of primary …


Nebraska Gap Analysis Project, G. M. Henebry, M. R. Vaitkus, James W. Merchant Feb 2008

Nebraska Gap Analysis Project, G. M. Henebry, M. R. Vaitkus, James W. Merchant

United States Geological Survey: Publications

The Nebraska Gap Analysis Project (NE-GAP) began in 1996 to assess the distribution and conservation status of biodiversity in the State under existing land ownership and management regimes. Our objectives were to (1) map land cover linked to dominant vegetation types; (2) map predicted distribution of terrestrial vertebrates; (3) document the representation of natural vegetation communities and animal species in areas managed for the long-term maintenance of biodiversity; and (4) make all information available to resource managers and land stewards in a readily accessible format.


A Watershed Analysis Of Pattee Pond: Implications For Water Quality And Land Use Management, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College Jan 2008

A Watershed Analysis Of Pattee Pond: Implications For Water Quality And Land Use Management, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College

Colby College Watershed Study: Pattee Pond (2008, 1992)

The Colby Environmental Assessment Team (CEAT) investigated the impact of land use patterns on the water quality of Pattee Pond in Winslow, Maine, during the summer and fall of 2008. Physical, chemical, and biological characteristics of water quality were analyzed to evaluate the current health of the lake. Data collected were compared with previous studies conducted by the Maine Department of Environmental Protection (DEP) and CEAT to examine changes in water quality and land use over time. Trends in Pattee Pond water quality suggest an improvement since the 1970s. However, the lake is still experiencing algal blooms resulting from phosphorus …


Sustainability In A Time Of Climate Change: Developing An Intensive Research Framework For The Platte River Basin And The High Plains Proceedings From The 2008 Climate Change Workshop, Monica Norby, Ashley Washburn Jan 2008

Sustainability In A Time Of Climate Change: Developing An Intensive Research Framework For The Platte River Basin And The High Plains Proceedings From The 2008 Climate Change Workshop, Monica Norby, Ashley Washburn

Office of Research and Economic Development: Publications

Proceedings from the 2008 Climate change Workshop, Nebraska Sandhills, May 19-22, 2008. Hosted by the University of Nebraska–Lincoln and the U.S. Geological Survey


How Human And Natural Driving Forces Affect Pheasants And Pheasant Hunting In South Dakota, Chris Laingen Jan 2008

How Human And Natural Driving Forces Affect Pheasants And Pheasant Hunting In South Dakota, Chris Laingen

Faculty Research and Creative Activity

No abstract provided.


The Dynamic Evolutionary History Of The Bananaquit (Coereba Flaveola) In The Caribbean Revealed By A Multigene Analysis, Eva Bellemain, Eldredge Bermingham, Robert Ricklefs Jan 2008

The Dynamic Evolutionary History Of The Bananaquit (Coereba Flaveola) In The Caribbean Revealed By A Multigene Analysis, Eva Bellemain, Eldredge Bermingham, Robert Ricklefs

Biology Department Faculty Works

BackgroundThe bananaquit (Coereba flaveola) is a small nectivorous and frugivorous emberizine bird (order Passeriformes) that is an abundant resident throughout the Caribbean region. We used multi-gene analyses to investigate the evolutionary history of this species throughout its distribution in the West Indies and in South and Middle America. We sequenced six mitochondrial genes (3744 base pairs) and three nuclear genes (2049 base pairs) for forty-four bananaquits and three outgroup species. We infer the ancestral area of the present-day bananaquit populations, report on the species' phylogenetic, biogeographic and evolutionary history, and propose scenarios for its diversification and range expansion.ResultsPhylogenetic concordance between …


Sampling Of Malodorous Compounds In Air Using Stir Bar Sorbtive Extraction, John H. Loughrin, Nanh Lovanh, Arturo I. Quintanar, Rezaul Mahmood Jan 2008

Sampling Of Malodorous Compounds In Air Using Stir Bar Sorbtive Extraction, John H. Loughrin, Nanh Lovanh, Arturo I. Quintanar, Rezaul Mahmood

High Plains Regional Climate Center: Staff Publications

Twisters, (poly)‐dimethylsiloxane‐coated magnetic stir bars, were used to measure compounds typical of swine manure malodor in air. In initial experiments, a time to achieve equilibrium was determined by preloading the stir bars with ten compounds with a range of volatilities and polarities and then monitoring their loss. The rate of loss was dependent on compound volatility, and the time for equilibrium to be attained varied widely, from 22 min for phenol to 210 min for skatole. To test whether the Twisters would respond linearly over a range of concentrations, the stir bars were placed in vented jars with solutions of …


Characterization Of Natural Spring Waters Of The San Bernardino Mountains Using Stable Isotopes Of Oxygen And Hydrogen, Alison Renee Sloat Jan 2008

Characterization Of Natural Spring Waters Of The San Bernardino Mountains Using Stable Isotopes Of Oxygen And Hydrogen, Alison Renee Sloat

Theses Digitization Project

The purpose of this study was to characterize the natural spring waters of the San Bernardino Mountains using two stable isotopes. The isotopic results of this study will aid with tracing sources, movements, and mixing effects on groundwater receiving mountain-front recharge in the region.


Distribution And Environmental Limitations Of An Amphibian Pathogen In The Rocky Mountains, Usa, Erin Muths, David S. Pilliod, Lauren J. Livo Jan 2008

Distribution And Environmental Limitations Of An Amphibian Pathogen In The Rocky Mountains, Usa, Erin Muths, David S. Pilliod, Lauren J. Livo

United States Geological Survey: Staff Publications

Amphibian populations continue to be imperiled by the chytrid fungus (Batrachochytrium dendrobatidis). Understanding where B. dendrobatidis (Bd) occurs and how it may be limited by environmental factors is critical to our ability to effectively conserve the amphibians affected by Bd. We sampled 1247 amphibians (boreal toads and surrogates) at 261 boreal toad (Bufo boreas) breeding sites (97 clusters) along an 11° latitudinal gradient in the Rocky Mountains to determine the distribution of B. dendrobatidis and examine environmental factors, such as temperature and elevation, that might affect its distribution. The fungus was detected at …


Introgression And Dispersal Among Spotted Owl (Strix Occidentalis) Subspecies, W. Chris Funk, Eric D. Forsman, Thomas D. Mullins, Susan M. Haig Jan 2008

Introgression And Dispersal Among Spotted Owl (Strix Occidentalis) Subspecies, W. Chris Funk, Eric D. Forsman, Thomas D. Mullins, Susan M. Haig

United States Geological Survey: Staff Publications

Population genetics plays an increasingly important role in the conservation and management of declining species, particularly for defining taxonomic units. Subspecies are recognized by several conservation organizations and countries and receive legal protection under the US Endangered Species Act (ESA). Two subspecies of spotted owls, northern (Strix occidentalis caurina) and Mexican (S. o. lucida) spotted owls, are ESA-listed as threatened, but the California (S. o. occidentalis) spotted owl is not listed. Thus, determining the boundaries of these subspecies is critical for effective enforcement of the ESA. We tested the validity of previously recognized spotted …


Tools And Technology Article: Estimation And Correction Of Visibility Bias In Aerial Surveys Of Wintering Ducks, Aaron T. Pearse, Patrick D. Gerard, Stephen J. Dinsmore, Richard M. Kaminski, Kenneth J. Reinecke Jan 2008

Tools And Technology Article: Estimation And Correction Of Visibility Bias In Aerial Surveys Of Wintering Ducks, Aaron T. Pearse, Patrick D. Gerard, Stephen J. Dinsmore, Richard M. Kaminski, Kenneth J. Reinecke

United States Geological Survey: Staff Publications

Incomplete detection of all individuals leading to negative bias in abundance estimates is a pervasive source of error in aerial surveys of wildlife, and correcting that bias is a critical step in improving surveys. We conducted experiments using duck decoys as surrogates for live ducks to estimate bias associated with surveys of wintering ducks in Mississippi, USA. We found detection of decoy groups was related to wedand cover type (open vs. forested), group size (1-100 decoys), and interaction of these variables. Observers who detected decoy groups reported counts that averaged 78% of the decoys actually present, and this counting bias …


Tools And Technology Article: Evaluation Of An Aerial Survey To Estimate Abundance Of Wintering Ducks In Mississippi, Aaron T. Pearse, Stephen J. Dinsmore, Richard M. Kaminski, Kenneth J. Reinecke Jan 2008

Tools And Technology Article: Evaluation Of An Aerial Survey To Estimate Abundance Of Wintering Ducks In Mississippi, Aaron T. Pearse, Stephen J. Dinsmore, Richard M. Kaminski, Kenneth J. Reinecke

United States Geological Survey: Staff Publications

Researchers have successfully designed aerial surveys that provided precise estimates of wintering populations of ducks over large physiographic regions, yet few conservation agencies have adopted these probability-based sampling designs for their surveys. We designed and evaluated an aerial survey to estimate abundance of wintering mallards (Anas platyrhynchos), dabbling ducks (tribe Anatini) other than mallards, diving ducks (tribes Aythini, Mergini, and Oxyurini), and total ducks in western Mississippi, USA. We used design-based sampling of fixed width transects to estimate population indices (/), and we used model-based methods to correct population indices for visibility bias and estimate population abundance (N) for 14 …


Grenetic Evidence Of Intercontinental Movement Of Avian Influenza In A Migratory Bird: The Northern Pintail (Anas Acuta), Anson V. Koehler, John M. Pearce, Paul L. Flint, J. Christian Franson, Hon S. Ip Jan 2008

Grenetic Evidence Of Intercontinental Movement Of Avian Influenza In A Migratory Bird: The Northern Pintail (Anas Acuta), Anson V. Koehler, John M. Pearce, Paul L. Flint, J. Christian Franson, Hon S. Ip

United States Geological Survey: Staff Publications

The role of migratory birds in the movement of the highly pathogenic (HP) avian influenza H5N1 remains a subject of debate. Testing hypotheses regarding intercontinental movement of low pathogenic avian influenza (LPAI) viruses will help evaluate the potential that wild birds could carry Asian-origin strains of HP avian influenza to North America during migration. Previous North American assessments of LPAI genetic variation have found few Asian reassortment events. Here, we present results from whole-genome analyses of LPAI isolates collected in Alaska from the northern pintail (Anas acuta), a species that migrates between North America and Asia. Phylogenetic analyses …


Degradation Of Chlorinated Ethenes In Mesocosms Simulating A Constructed Wetland, At Wpafb, Ohio, Dibyendu Mukherjee Jan 2008

Degradation Of Chlorinated Ethenes In Mesocosms Simulating A Constructed Wetland, At Wpafb, Ohio, Dibyendu Mukherjee

Browse all Theses and Dissertations

The main purpose of this research was to study the degradation of chlorinated ethenes in upwardflowing mesocosms, simulating a constructed wetland at Wright Patterson Air Force Base (WPAFB) in Dayton, Ohio. This research was intended to compare biogeochemical processes and PCE degradation occurring in the mesocosms and in the field site. This research also tries to look at the effects of vegetation and season on the degradation efficiency of the mesocosms. Twelve PVC column reactors were built within the greenhouse of Wright State University in September 2005 to simulate the hydraulic conditions of a constructed wetland at WPAFB. The columns …


Droughtscape, Winter 2008, Kelly Smith Jan 2008

Droughtscape, Winter 2008, Kelly Smith

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Now Up & On-Line:

Winter 2008 Outlook and Oct.-Dec. ’07 Summary

NDMC Experts Serve as Resource for Media

Drought Hits Ag and Urban Interests in 2007

Climatological Summary of Drought in 2007

NDMC Welcomes Data Miner Bo Zhang

New Grant Awards


The Geology Of Ukhaa Tolgod (Djadokhta Formation, Upper Cretaceous, Nemegt Basin, Mongolia), Lowell Dingus, David B. Loope, Demberlyin Dashzeveg, Carl C. Swisher Iii, Chuluun Minjin, Michael J. Novacek, Mark A. Norell Jan 2008

The Geology Of Ukhaa Tolgod (Djadokhta Formation, Upper Cretaceous, Nemegt Basin, Mongolia), Lowell Dingus, David B. Loope, Demberlyin Dashzeveg, Carl C. Swisher Iii, Chuluun Minjin, Michael J. Novacek, Mark A. Norell

Department of Earth and Atmospheric Sciences: Faculty Publications

The lithostratigrahy and sedimentology of the fossiliferous Upper Cretaceous strata exposed in the Gobi Desert of Mongolia at Ukhaa Tolgod are described and mapped on aerial photos. Topographic features are also mapped by plane table and alidade.

Five lithologic and sedimentologic facies are described: E-1, distinctly cross-stratified sandstone with fine structure, interpreted to represent eolian dune deposits; E-2, vaguely bedded sandstone with cross-stratified concretionary sheets, interpreted to represent eolian dune deposits modified by diagenetic formation of slope-parallel concretionary sheets of pedogenic calcite; S, structureless sandstone lacking concretions or cross-strata, interpreted to represent sandslide deposits generated by mass wasting along the …


Mullewa Research Annexe Spring Field Day Future Farming Systems For North-Eastern Districts 21 August 2008, Department Of Agriculture, Western Australia Jan 2008

Mullewa Research Annexe Spring Field Day Future Farming Systems For North-Eastern Districts 21 August 2008, Department Of Agriculture, Western Australia

Grain and other field crops research reports

Papers:

  • Mullewa Research Annexe activities 2008

  • Wheat for today and the future

  • Consequences of strongly acidic and alkaline soils

  • Break crop influence on low rainfall heavy soil

  • Chemical fallow options for the north-east agricultural region

  • Herbicide tolerance of new wheat varieties

  • Lowrainfall oilseed crops for food and biofuel

  • Utilising stock to reduce business risk in Binnu! A case study


The Mobility Of Fecal Indicator Microorganisms Within A Karst Groundwater Basin In The Inner Bluegrass Region, Kentucky, James Wade Ward Jan 2008

The Mobility Of Fecal Indicator Microorganisms Within A Karst Groundwater Basin In The Inner Bluegrass Region, Kentucky, James Wade Ward

University of Kentucky Doctoral Dissertations

This project implemented novel approaches to assess the source, age, concentration and mobility of fecal indicator microorganisms within a karst groundwater system. Research was conducted in the well-characterized Blue Hole Spring karst groundwater basin in Versailles, Woodford County, Kentucky. At this site the AC/TC ratio and fecal coliform (FC) bacteria counts were used to delineate sources of fecal inputs and determine relative age of the fecal matter. An aging experiment using indicator bacteria (total coliform (TC) and atypical colonies (AC)), which approximated subsurface conditions, indicated that changes in the AC/TC ratio are likely to be retarded during bacterial transport through …


Groundwater Quality In Watersheds Of The Big Sandy River, Little Sandy River, And Tygarts Creek (Kentucky Basin Management Unit 5), R. Stephen Fisher, Bart Davidson, Peter T. Goodmann Jan 2008

Groundwater Quality In Watersheds Of The Big Sandy River, Little Sandy River, And Tygarts Creek (Kentucky Basin Management Unit 5), R. Stephen Fisher, Bart Davidson, Peter T. Goodmann

Report of Investigations--KGS

The Kentucky Geological Survey and the Kentucky Division of Water are evaluating groundwater quality throughout the commonwealth to determine regional conditions, assess impacts of nonpoint-source contaminants, provide a baseline for tracking changes, and provide essential information for environmental-protection and resource-management decisions. These evaluations include summarizing existing regional groundwater-quality data and reporting the results of expanded, focused groundwater collection programs in specific areas. This report summarizes groundwater sampling and analysis in Kentucky basin management unit 5 (watersheds of the Big Sandy River, Little Sandy River, and Tygarts Creek in eastern Kentucky).

Thirty wells and springs were sampled quarterly between the fall …


Correlation Of Electron Donor Concentrations In Sediments With Sediment Properties: New Providence, Iowa, Bijesh Maharjan Jan 2008

Correlation Of Electron Donor Concentrations In Sediments With Sediment Properties: New Providence, Iowa, Bijesh Maharjan

Theses and Dissertations

The concentrations of electron donors in aquifer sediments are important in understanding the fate and transport of redox-sensitive constituents in ground water, such as nitrate. In this study, 50 sediment samples were collected from below the water table from 11 boreholes at the US Geological Survey Agricultural Chemicals Transport site near New Providence, Iowa. All samples were analyzed for gravel, sand (coarse, medium, and fine), silt, clay, inorganic carbon contents and for the following electron donors: organic carbon, ferrous iron, and inorganic sulfide. A subset of sediment samples was analyzed for organic sulfur, but all of the 14 samples were …


Historic Resource Study: Agate Fossil Beds National Monument, Gail Evans-Hatch Jan 2008

Historic Resource Study: Agate Fossil Beds National Monument, Gail Evans-Hatch

United States National Park Service: Publications

As steward of many of the United States' most important cultural and natural resources, the National Park Service (NPS) is required to create background documents along with specific plans aimed at managing and protecting these resources for the enjoyment of present and future generations. An important aspect of managing cultural landscapes requires knowing the past of those landscapes. A historic resource study (HRS) project involves researching and presenting the history of a park. A HRS also attempts to identify and evaluate the importance of all cultural resources within that park. Researching and presenting the broader historical context of a park …


Summary And Analysis Of The U.S. Government Bat Banding Program, Laura Ellison Jan 2008

Summary And Analysis Of The U.S. Government Bat Banding Program, Laura Ellison

United States Geological Survey: Publications

This report is a summary of the Bat Banding Program (BBP) administered, coordinated, and maintained by the U.S. Bureau of Biological Survey in the Department of Agriculture and its successor, the U.S. Fish and Wildlife Service in the Department of the Interior from 1932 to 1972. Bands were issued and copies of the permanent records were maintained at the Bird and Mammal Laboratories, U.S. National Museum, Washington, D.C., during the active parts of the program (1932–72). Following various agency transfers within the Department of the Interior, the files and documentation for this program are currently maintained in the same location, …


Apparent Tolerance Of Turkey Vultures (Cathartes Aura) To The Non-Steroidal Anti-Inflammatory Drug Diclofenac, Barnett A. Rattner, Maria A. Whitehead, Grace Gasper, Carol U. Meteyer, William A. Link, Mark A. Taggart, Andrew A. Meharg, Oliver H. Pattee, Deborah J. Pain Jan 2008

Apparent Tolerance Of Turkey Vultures (Cathartes Aura) To The Non-Steroidal Anti-Inflammatory Drug Diclofenac, Barnett A. Rattner, Maria A. Whitehead, Grace Gasper, Carol U. Meteyer, William A. Link, Mark A. Taggart, Andrew A. Meharg, Oliver H. Pattee, Deborah J. Pain

United States Geological Survey: Staff Publications

The nonsteroidal anti-inflammatory drug diclofenac is extremely toxic to Old World Gyps vultures (median lethal dose ~0.1–0.2 mg/kg), evoking visceral gout, renal necrosis, and mortality within a few days of exposure. Unintentional secondary poisoning of vultures that fed upon carcasses of diclofenac-treated livestock decimated populations in the Indian subcontinent. Because of the widespread use of diclofenac and other cyclooxygenase-2 inhibiting drugs, a toxicological study was undertaken in turkey vultures (Cathartes aura) as an initial step in examining sensitivity of New World scavenging birds. Two trials were conducted entailing oral gavage of diclofenac at doses ranging from 0.08 to …


Intelligent Environmental Decision Support Systems, M. Sànchez-Marrè, K. Gibert, R. S. Sojda, J. P. Steyer, P. Struss, I. Rodríguez-Roda, J. Comas, V. Brilhante, E. A. Roehl Jan 2008

Intelligent Environmental Decision Support Systems, M. Sànchez-Marrè, K. Gibert, R. S. Sojda, J. P. Steyer, P. Struss, I. Rodríguez-Roda, J. Comas, V. Brilhante, E. A. Roehl

United States Geological Survey: Staff Publications

Introduction
Complexity of environmental systems
New tools for a new paradigm
Intelligent Environmental Decision Support Systems (IEDSS)
IEDSS development
About Uncertainty Management
Temporal Reasoning
Featuring the problem
Approaches to temporal reasoning
Case-based reasoning for temporal reasoning
Geographic Information and Spatial Reasoning
Understanding spatial reasoning
Kriging and variants
Representing change/time steps/feedback loops
Middleware. blackboards and communication protocols
Multiagent systems
Evaluation of IEDSS and Benchmarking
Benchmarking
Conclusions and Future Trends


Lateral Reservoir Compartmentalization Of The Woodford Shale In The Arkoma Basin, Southeastern Oklahoma, Adedapo Omotunde Ajibade Jan 2008

Lateral Reservoir Compartmentalization Of The Woodford Shale In The Arkoma Basin, Southeastern Oklahoma, Adedapo Omotunde Ajibade

Masters Theses

"Analysis of geochemistry, mineralogy, total organic content (TOC) and rock evaluation pyrolysis on Woodford Shale well cuttings taken from a horizontal well (Quaid 13-30H) drilled in the Arkoma Basin (Pittsburg County), Oklahoma shows no significant variation in the thermal maturity, type, and/or quantity of organic matter. This is interpreted to mean that the organic matter of the Woodford Shale is relatively homogeneous and has all undergone similar thermal history. In addition, the analysis shows that there are lateral variations in the gas geochemistry in which the shale appears to be broken up into sections, some of which are more enhanced …


Groundwater Contamination In Caves: Four Case Studies In Spain, Monserrat Jiménez-Sánchez, Heather Stoll, Iñaki Vadillo, Manolo López-Chicano, María Domínguez-Cuesta, Wenceslao Martín-Rosales, Mónica Meléndez-Asensio Jan 2008

Groundwater Contamination In Caves: Four Case Studies In Spain, Monserrat Jiménez-Sánchez, Heather Stoll, Iñaki Vadillo, Manolo López-Chicano, María Domínguez-Cuesta, Wenceslao Martín-Rosales, Mónica Meléndez-Asensio

International Journal of Speleology

Groundwater quality was monitored in four Spanish caves using concentrations of nitrate, potassium, phosphorus and in some cases total organic carbon. Three of the caves are located in NW Spain and contain prehistoric cave paintings and hence have special conservation interest. Of these, two are open show caves (Tito Bustillo and Pindal Caves), while the other one (Herrerías Cave) is not managed for tours and is partially closed off to public access. The fourth cave (Las Maravillas Cave) is located in SW Spain and is opened to the public because of its geological features and natural beauty. In this paper, …


The Balancing Act, David Weaver Jan 2008

The Balancing Act, David Weaver

Conference papers and presentations

Nutrient management is as much a global issue as a local one with a balance required between economics and environment, inherent biological limitations and expectations of nutrient use efficiency, and traditional fertiliser practices and actual enterprise nutrient requirements. The concept of nutrient balance depends on context and scale. Nutrient balance can be considered at a global scale, where issues of nutrient stocks, cycles, depletion and transfer of a particular element are important. For a single farm enterprise, nutrient balance might be considered in terms of phosphorus (P) inputs into and outputs from the enterprise. This is commonly known as a …


Reclamation Of Saline Soils Through Revegetation In Australia: Plants, Processes And People, Edward G. Barrett-Lennard Jan 2008

Reclamation Of Saline Soils Through Revegetation In Australia: Plants, Processes And People, Edward G. Barrett-Lennard

Conference papers and presentations

Secondary salinity (salinity induced by human activity) is a major world problem. Hydrological imbalances in landscapes cause watertables to rise, drawing salt from deeper in the soil profile to the soil surface, where the combined stresses of salinity and waterlogging threaten the growth of crops and pastures. The reversal of salinity by the broad‐scale reintroduction of perennial plants back into landscapes may not be economically feasible, but watertables may be at least partly directly drawn‐down by the grow th of salt tolerant plants (halophytes) on saltland . This review summarises data from Australia in which the water use by perennial …


Dactyls Reveal Evolutionary Patterns In Decapod Crustaceans, Jeffrey Guy Agnew Jan 2008

Dactyls Reveal Evolutionary Patterns In Decapod Crustaceans, Jeffrey Guy Agnew

LSU Doctoral Dissertations

Because of their high preservation potential and uses in foraging and defense, decapod crustacean dactyls (movable fingers of claws) are potentially excellent test subjects for an ongoing debate concerning the relative importance of top-down (predators) and bottom-up (prey) controls on morphologic diversification and evolution. The utility of dactyls for inferring evolutionary patterns were evaluated using living and subfossil xanthoid crabs sampled from the southeast U.S. Atlantic and Gulf of Mexico coasts, and were used to: (1) distinguish the roles of selection and constraint on dactyl morphology through allometric and shape comparisons in the context of the crab’s phylogenetic relationships and …