Digital Commons Network^™

Addressing Uncertainty In Tmdls: Short Course At Arkansas Water Resources Center 2001 Annual Conference, Marty Matlock, Matthew Murawski

Arkansas Water Resources Center Technical Reports

Management of a critical natural resource like water requires information on the status of that resource. The US Environmental Protection Agency (EPA) reported in the 1998 National Water Quality Inventory that more than 291,000 miles of assessed rivers and streams and 5 million acres of lakes do not meet State water quality standards. This inventory represents a compilation of State assessments of 840,000 miles of rivers and 17.4 million acres of lakes; a 22 percent increase in river miles and 4 percent increase in lake acres over their 1996 reports. Siltation, bacteria, nutrients and metals were the leading pollutants of …

Evidence Of Earliest Known Wildfires, Walter L. Cressler Iii

Earth & Space Sciences Faculty Publications

No abstract provided.

Am-Pm Cutting Of Alfalfa, Garry D. Lacefield, Michael Collins, Jimmy C. Henning

Kentucky Alfalfa and Stored Forage Conference

Over the past twenty years of this Conference we have spent considerable time discussing "Alfalfa Harvest Management." We have discussed the importance of stage of maturity and its impact on quality on many occasions. We have presented research on many aspects of hay and haylage management. An overall theme for all the discussions has been "harvest for quality," with emphasis on saving the leaves during the entire harvesting process. Our recommendations have, are, and will continue to be centered around those management practices that will result in the greatest opportunity for preserving alfalfa quality from standing crop to feeding. This …

Locating Nests Of Birds In Grasslands From A Mobile Tower Blind, Thomas F. Fondell, Steven T. Hoekman, I. J. Ball

United States Geological Survey: Staff Publications

Locating nests of grassland passerines can be difficult, labor intensive, and disruptive to birds and vegetation. We developed a mobile tower blind for observing adult bird behavior and used it to locate nests in a western Montana grassland. We compared nest-search efficiency of behavioral observations from the tower versus the ground. Nests of savannah sparrow (Passerculus samhvichensis) were found in a higher proportion of territories searched from the tower (13/16 = 82%) than from the ground (4113 = 3 1%). Average search time for each nest found was lower from the tower (44 min) than from the ground …

Tropical Climate Changes At Millennial And Orbital Timescales On The Bolivian Altiplano, Paul A. Baker, Catherine A. Rigsby, Geoffrey O. Seltzer, Sherilyn C. Fritz, Tim K. Lowenstein, Niklas P. Bacher, Carlos Veliz

Department of Earth and Atmospheric Sciences: Faculty Publications

Tropical South America is one of the three main centers of the global, zonal overturning circulation of the equatorial atmosphere (generally termed the “Walker” circulation). Although this area plays a key role in global climate cycles, little is known about South American climate history. Here we describe sediment cores and down-hole logging results of deep drilling in the Salar de Uyuni, on the Bolivian Altiplano, located in the tropical Andes. We demonstrate that during the past 50,000 years the Altiplano underwent important changes in effective moisture at both orbital (20,000-year) and millennial timescales. Long-duration wet periods, such as the Last …

Demonstration Of Best Management Practices For The Protection And Improvement Of The Soil And Water Resources In The Arkansas Delta, M. A. Henslee, W. H. Baker, S. D. Carroll, J. L. Farris, S. D. Davis, C. D. Milam, J. L. Pierce

Arkansas Water Resources Center Technical Reports

This report is the compilation of a multi~year project that was directed at identifying the impact and possible mitigation solutions of non-point pollution from row crop agriculture in a watershed in the Arkansas Delta. The first part of the project involved an inventory of the condition of the major streams that make up the study watershed. The remainder of the project was focused at demonstrating and reporting best management nutrient and sediment runoff control practices (BMP) that could be implemented. The final assessment of the demonstration work is a GIS analysis that provides an overview of the effectiveness of these …

The History Of South American Tropical Precipitation For The Past 25,000 Years, Paul A. Baker, Geoffrey O. Seltzer, Sherilyn C. Fritz, Robert B. Dunbar, Matthew J. Grove, Pedro M. Tapia, Scott L. Cross, Harold D. Rowe, James P. Broda

Department of Earth and Atmospheric Sciences: Faculty Publications

Long sediment cores recovered from the deep portions of Lake Titicaca are used to reconstruct the precipitation history of tropical South America for the past 25,000 years. Lake Titicaca was a deep, fresh, and continuously overflowing lake during the last glacial stage, from before 25,000 to 15,000 calibrated years before the present (cal yr B.P.), signifying that during the last glacial maximum (LGM), the Altiplano of Bolivia and Peru and much of the Amazon basin were wetter than today. The LGM in this part of the Andes is dated at 21,000 cal yr B.P., approximately coincident with the global LGM. …

A New Species Of Extinct Oryzomyine Rodent From The Quaternary Of Curaçao, Netherlands Antilles, Donald A. Mcfarlane, Adolphe O. Debrot

WM Keck Science Faculty Papers

An extinct new species of Oryzomyine rodent, known since 1936 from the cave of Grot van Hato on the island of Curaçao, is described from abundant new specimens collected from owl-pellet deposits at three localities on the island.

Ecoregions Of Nebraska And Kansas, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Ecoregions denote areas of general similarity in ecosystems and in the type, quality, and quantity of environmental resources; they are designed to serve as a spatial framework for the research, assessment, management, and monitoring of ecosystems and ecosystem components. Ecoregions are directly applicable to the immediate needs of state agencies, including the development of biological criteria and water quality standards, and the establishment of management goals for nonpoint-source pollution. They are also relevant to integrated ecosystem management, an ultimate goal of most federal and state resource management agencies. The approach used to compile this map is based on the premise …

Extent And Impacts Of Dryland Salinity, Rod Short, Cecilia Mcconnell

Resource management technical reports

The National Land and Water Resource Audit (NLWRA) identified Dryland Salinity (Theme 2) as one of seven major themes for an audit of the nation's land, water, vegetation and natural resources. Within this theme, Project 1 was developed to identify the Extent and Impact of Dryland Salinity nationally. This report details the results from work done in Western Australia (WA) to meet the Audit requirements.

Karst Genetic Model For The French Bay Breccia Deposits, San Salvador, Bahamas, Lee J. Florea, John Mylroie, Jim Carew

Earth, Environmental, and Atmospheric Sciences Faculty Publications

No abstract provided.

Blackwood Catchment : Katanning Zone (Zone 6) : Catchment Appraisal 2001, Henry Brockman, Blackwood Rapid Catchment Appraisal Team (Wa)

Resource management technical reports

The aim of this report is to document the extent of salinity and land degradation within the Katanning zone, Western Australia, and management options aimed at reducing recharge and land degradation.

Extent And Impacts Of Dryland Salinity, C E. Mcconnell, R Short

Resource management technical reports

The extent and impact of dryland salinity in Western Australia was based on analysis of groundwater depth and trend and the risk of shallow watertables is derived from these two attributes. As dryland salinity is caused by shallow watertables, the risk of salinity is inferred from the risk of shallow watertables.

Citizen Knowledge And Perception Of Black-Tailed Prairie Dog Management, Natalie R. Sexton, Ayeisha Brinson, Phadrea D. Ponds, Kurt Cline, Berton L. Lamb

United States Geological Survey: Publications

What do citizens know about black-tailed prairie dogs, and where do they get their information? When management decisions need to be made regarding an animal such as the black-tailed prairie dog, an understanding of the species and its relationship to humans is necessary. This includes knowing the biology of the animal, where it lives, and how it interacts with other animals. But it is equally important for those making decisions about the species to understand citizens’ knowledge and perceptions so managers can effectively communicate with the public and help the public participate in planning and decision making activities. Unfortunately, what …

Occurrence And Potential Adverse Effects Of Semivolatile Organic Compounds In Streambed Sediment, United States, 1992–1995, Thomas J. Lopes, Edward T. Furlong

United States Geological Survey: Staff Publications

The occurrence and potential adverse effects of select semivolatile organic compounds (SVOCs) in streambed sediment were assessed at 536 sites in 20 major river basins across the United States from 1992 to 1995. Fifty-six SVOCs were detected at one or more sites, and one or more SVOCs were detected at 71% of sites. The northeastern and Great Lakes regions and large metropolitan areas have the highest SVOC concentrations. Polycyclic aromatic hydrocarbons (PAHs) were detected most frequently and at the highest concentrations. Concentrations of PAHs and phthalates were about 10 times higher at sites influenced by urban activities than at sites …

Soil Factors Influencing Eutrophication. In Soilguide. A Handbook For Understanding And Managing Agricultural Soils. (Ed. Geoff Moore), David Weaver, Robert Summers

Bulletins 4000 -

Eutrophication is essentially the nutrient enrichment of waterways leading to algal growth. It must be controlled to maintain sustainable agricultural systems and the main mechanisms of control are stabilising catchment processes and reducing nutrient output.

Eutrophication can be defined as 'the nutrient enrichment of waters which results in the stimulation of an array of symptomatic changes, among which increased production of algae and macrophytes, deterioration of water quality and other symptomatic changes, are found to be undesirable and interfere with water uses' (OECD 1982). The word eutrophic is a Greek word that means 'well fed'. The food referred to is …

Cruise Reveals History Of Holocene Larsen Ice Shelf, Eugene Domack, Amy Leventer, Robert Gilbert, Stefanie Brachfeld, Scott Ishman, Angelo Camerlenghi, Kathleen Gavahan, David Carlson, Athen Barkoukis

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

No abstract provided.

Uptake Of Dissolved Organic Selenides By Marine Phytoplankton, Stephen B. Baines, Nicholas S. Fisher, Martina A. Doblin, Gregory A. Cutter

OES Faculty Publications

Se is present in multiple oxidation states in nature, each of which has unique chemical and biological reactivities. As a consequence, the rate of Se incorporation into food webs or its role as either a limiting nutrient or a toxic substance is a function of complex biogeochemistry. In particular, little is understood about the accumulation of dissolved organic selenides by phyto- or bacterioplankton. We assessed the bioavailability of dissolved organic selenides to marine and estuarine phytoplankton by presenting various algal species with filtered lysates of the diatom, Thalassiosira pseudonana, grown on media amended with radiolabeled selenite (⁷⁵Se[IV]). …

Control Of Phytoplankton Growth By Iron Supply And Irradiance In The Subantarctic Southern Ocean: Experimental Results From The Saz Project, P. W. Boyd, A. C. Crossley, G. R. Ditullio, F. B. Griffiths, D. A. Hutchins, B. Queguiner, Peter N. Sedwick, T. W. Trull

OES Faculty Publications

The influence of irradiance and Fe supply on phytoplankton processes was studied, north (47°S, 142°E) and south (54°S, 142°E) of the Subantarctic Front in austral autumn (March 1998). At both sites, resident cells exhibited nutrient stress (F_v/F_m 0 at 47°S and 9% I₀ at 54°S because of MLDs of 40 (47°S) and 90 m (54°S), when these stations were occupied. The greater MLD at 54°S is reflected by tenfold higher cellular chlorophyll a levels in the resident phytoplankton. In the 47°S experiment, chlorophyll a levels increased to >1 μg/L^-1 only in the high-Fe treatments, regardless …

Control Of Phytoplankton Growth By Iron And Silicic Acid Availability In The Subantarctic Ocean: Experimental Results From The Saz Project, D. A. Hutchins, Peter N. Sedwick, G. R. Ditullio, P. W. Boyd, B. Queguiner, F. B. Griffiths, C. Crossley

OES Faculty Publications

Subantarctic Southern Ocean surface waters in the austral summer and autumn are characterized by high concentrations of nitrate and phosphate but low concentrations of dissolved iron (Fe, similar to0.05 nM) and silicic acid (Si, <1 muM). During the Subantarctic Zone AU9706 cruise in March 1998 we investigated the relative importance of Fe and Si in controlling phytoplankton growth and species composition at a station within the subantarctic water mass (46.8degreesS, 142degreesE) using shipboard bottle incubation experiments. Treatments included unamended controls; 1.9 nM added iron (+Fe); 9 muM added silicic acid (+Si); and 1.9 nM addediron plus 9 muM added silicic acid (+Fe+Si). We followed a detailed set of biological and biogeochemical parameters over 8 days. Fe added alone clearly increased community growth rates and nitrate drawdown and altered algal community composition relative to control treatments. Surprisingly, small, lightly silicified pennate diatoms grew when Fe was added either with or without Si, despite the extremely low ambient silicic acid concentrations. Pigment analyses suggest that lightly silicified chrysophytes (type 4 haptophytes) may have preferentially responded to Si added either with or without Fe. However, for many of the parameters measured the +Fe+Si treatments showed large increases relative to both the +Fe and +Si treatments. Our results suggest that iron is the proximate limiting nutrient for chlorophyll production, photosynthetic efficiency, nitrate drawdown, and diatom growth, but that Si also exerts considerable control over algal growth and species composition. Both nutrients together are needed to elicit a maximum growth response, suggesting that both Fe and Si play important roles in structuring the subantarctic phytoplankton community.

Holocene Sediment Records From The Continental Shelf Of Mac. Robertson Land, East Antarctica, Peter N. Sedwick, Peter T. Harris, Lisette G. Robertson, Gary M. Mcmurtry, Maximilian D. Cremer, Philip Robinson

OES Faculty Publications

Geochemical records are presented for five sediment cores from basins on the continental shelf of Mac. Robertson Land, East Antarctica. The cores contain 2-4 m thick sequences of hemipelagic, siliceous mud and ooze (SMO) deposited under seasonally open marine conditions. The inner and middle shelf SMO sequences are massive dark olive green material, whereas the outer shelf SMO sequences are dark olive material interspersed with light olive green layers similar to1-10 cm thick. The biogenic material is dominated by marine diatoms including Fragilariopsis curta, Fragilariopsis cylindrus, and Chaetoceros spp. in the dark-colored SMO and Corethron criophilum in the …

Introduction To Special Section: Saz Project, T. W. Trull, Peter N. Sedwick, F. B. Griffiths, S. R. Rintoul

OES Faculty Publications

Oceanographic processes in the subantarctic region contribute crucially to the phys. and biogeochemical aspects of the global climate system. To explore and quantify these contributions, the Antarctic Cooperative Research Center organized the SAZ Project, a multidisciplinary, multiship study carried out south of Australia in the austral summer of 1997-1998. We present an overview of the SAZ Project and some of its major results.

Effects Of Iron, Silicate, And Light On Dimethylsulfoniopropionate Production In The Australian Subantarctic Zone, G. R. Ditullio, P. N. Sedwick, D. R. Jones, P. W. Boyd, A. C. Crossley, D. A. Hutchins

OES Faculty Publications

Shipboard bottle incubation experiments were performed to investigate the effects of iron, light, and silicate on algal production of particulate dimethylsulfoniopropionate (DMSP_p) in the Subantarctic Zone (SAZ) south of Tasmania during March 1998. Iron enrichment resulted in threefold to ninefold increases in DMSP_p concentrations relative to control treatments, following 7 and 8-day incubation experiments. Additions of Fe and Si preferentially stimulated the growth of lightly-silicified pennate diatoms and siliceous haptophytes, respectively, to which we attribute the increased DMSP_p production in the incubation bottles. Both of these algal groups were previously believed to be low DMSP_{p …}

Iron In East Antarctic Snow: Implications For Atmospheric Iron Deposition And Algal Production In Antarctic Waters, Ross Edwards, Peter N. Sedwick

OES Faculty Publications

To evaluate the deposition and solubility of aerosol iron in the Antarctic seasonal sea ice zone (SSIZ), iron was measured in snow samples collected from three areas in the SSIZ (Prydz Bay, Dumont d'Urville Sea and Ross Sea) and one continental area (Princess Elizabeth Land) of East Antarctica. Concentrations of total-dissolvable iron (that soluble at pH ~2) ranged from 20-2950 pg g^-1, with the lowest concentrations measured in snow from the Dumont d'Urville Sea. Using estimates of snow accumulation rates, we calculate atmospheric iron deposition fluxes of 0.017-0.11 mg m^-2 yr^-1(0.30-2.0 μmol m^-2 yr …

Laboratory Denitrification Using Sediments From The Elk Valley Aquifer, Alison E. Kammer

Theses and Dissertations

An experiment was conducted to determine if a decrease in the content of sulfides related to denitrification could be measured in the laboratory using sediments of the Elk Valley Aquifer in eastern North Dakota. The experiment entailed analyzing sediments for sulfides and solid organic carbon and isolating them in sample containers with a nitrate solution to determine if a measurable decrease in these components could be observed.

Previous denitrification studies in the Elk Valley Aquifer showed an increase in sulfate in conjunction with a decrease in the concentration of nitrate. Sulfate is a by product of autotrophic denitrification where sulfide …

Modeling Reptile And Amphibian Range Distributions From Species Occurrences And Landscape Variables, Geoffrey M. Henebry, Brian C. Putz, James W. Merchant

United States Geological Survey: Publications

An international symposium in October 1999 demonstrated the state of the art in modeling species occurrences (Scott et al. 2001). One clear message from the symposium was the broad diversity of approaches that constitute the state of the art. No single method excels, largely because of the very particular and local nature of the problem. Organisms both influence and respond to their local environment; thus, the same species may key in on different resources in different landscapes. Furthermore, modeling methods vary widely in their "transparency," which can inhibit transportability or robustness.
In order to provide an analytical modeling framework that …

Inhibition Of Erythrocyte Δ- Aminolevulinic Acid Dehydratase (Alad) Activity In Fish From Waters Affects By Lead Smelters, Christopher J. Schmitt, Colleen A. Caldwell, Bill Olsen, Dave Serdar

United States Geological Survey: Staff Publications

We assessed the effects on fish of lead (Pb) released to streams by smelters located in Trail, BC (Canada), E. Helena, MT, Herculaneum, MO, and Glover, MO. Fish were collected by electrofishing from sites located downstream of smelters and from reference sites. Blood from each fish was analyzed for δ-aminolevulinic acid dehydratase (ALAD) activity and hemoglobin (Hb), and samples of blood, liver, or carcass were analyzed for Pb, zinc (Zn), or both. Fish collected downstream of all four smelters sites had elevated Pb concentrations, decreased ALAD activity, or both relative to their respective reference sites. At E. Helena, fish from …

Regional Variations In Provenance And Abundance Of Ice-Rafted Clasts In Arctic Ocean Sediments: Implications For The Configuration Of Late Quaternary Oceanic And Atmospheric Circulation In The Arctic, R. L. Phillips, A. Grantz

United States Geological Survey: Staff Publications

The composition and distribution of ice-rafted glacial erratics in late Quaternary sediments define the major current systems of the Arctic Ocean and identify two distinct continental sources for the erratics. In the southern Amerasia basin up to 70% of the erratics are dolostones and limestones (the Amerasia suite) that originated in the carbonate-rich Paleozoic terranes of the Canadian Arctic Islands. These clasts reached the Arctic Ocean in glaciers and were ice-rafted to the core sites in the clockwise Beaufort Gyre. The concentration of erratics decreases northward by 98% along the trend of the gyre from southeastern Canada basin to Makarov …

2,3,7,8-Tetrachlorodibenzo-P-Dioxin Induces Apoptotic Cell Death And Cytochrome P4501a Expression In Developing Fundulus Heteroclitus Embryos, Barbara Holland Toomey, Susan Bello, Mark E. Hahn, Susannah Cantrell, Peggy Wright, Donald E. Tillitt, Richard T. Di Giulio

United States Geological Survey: Staff Publications

Fundulus heteroclitus embryos were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) during early development using nanoinjection or water bath exposure. TCDD caused developmental abnormalities that included hemorrhaging, loss of vascular integrity, edema, stunted development and death. The LC₅₀ and LD₅₀ of TCDD for Fundulus embryos were ~19.7 ± 9.5 pg TCDD/µl (water bath) and 0.25 ± 0.09 ng TCDD/g embryo (nanoinjection). To identify a possible cause for these developmental abnormalities we analyzed the effects of TCDD on apoptotic cell death and cytochrome P4501A (CYP1A) expression in the embryos. TCDD exposure increased apoptotic cell death in several tissues including brain, …

Effect Of Scale On The Behavior Of Atrazine In Surface Waters, Paul Capel, Steven Larson

United States Geological Survey: Staff Publications

Field runoff is an important transport mechanism by which agricultural pesticides, including atrazine, move into the hydrologic environment. Atrazine is chosen because it is widely used, is transported in runoff relatively easily, is widely observed in surface waters, and has relatively little loss in the stream network. Data on runoff of atrazine from experimental plot and field studies is combined with annual estimates of load in numerous streams and rivers, resulting in a data set with 408 observations that span 14 orders of magnitude in area. The load as a percent of use (LAPU) on an annual basis is the …