Physical Sciences and Mathematics Commons^™

Molecular Techniques Reveal Wide Phyletic Diversity Of Heterotrophic Microbes Associated With Discodermia Spp. (Porifera: Demospongiae), Jose V. Lopez, Peter J. Mccarthy, Kathleen E. Janda, Robin Willoughby, Shirley A. Pomponi

Marine & Environmental Sciences Faculty Articles

Sponges are well known to harbor large numbers of heterotrophic microbes within their mesohyl. Studies to determine the diversity of these associated microbes have been attempted for only a few shallow water species. We cultured various microorganisms from several species of Discodermia collected from deep water using the 'Johnson-Sea-Link' manned submersibles, and characterised them by standard microbiological identification methods. Characterisation of a small proportion (ca. 10%) of the total and potential eubacterial isolate collection with molecular systematics techniques revealed a wide diversity of microbes. Phylogenetic analyses of 32 small subunit (SSU) 16S-like rRNA gene sequences from different micorbes indicated high …

Concentrations And Snow-Atmosphere Fluxes Of Reactive Nitrogen At Summit, Greenland, J W. Munger, D J. Jacob, S M. Fan, A S. Colman, Jack E. Dibb

Earth Sciences

Concentrations and fluxes of NO_y (total reactive nitrogen), ozone concentrations and fluxes of sensible heat, water vapor, and momentum were measured from May 1 to July 20, 1995 at Summit, Greenland. Median NO_y concentrations declined from 947 ppt in May to 444 ppt by July. NO_y fluxes were observed into and out of the snow, but the magnitudes were usually below 1 μmol m⁻² h⁻¹ because of the low HNO₃ concentration and weak turbulence over the snow surface. Some of the highest observed fluxes may be due to temporary storage by equilibrium sorption of …

Collaborative Research: Long Records Of Paleoclimate From Florida, George L. Jacobson, Heather Almquist

University of Maine Office of Research Administration: Grant Reports

Long Records of Paleoclimate from Florida Recent research on a continuous 50,000-year sediment record from eastern North America has revealed a striking correlation between Heinrich events (large surges in flow of ice streams feeding from the Laurentide ice sheet into the North Atlantic) and major changes in vegetation in peninsular Florida. These events are expressed at Lake Tulane, Florida, as abrupt shifts between pine-dominated and oak-dominated communities, which likely correspond with times of moist climate alternating with periods of extreme drought. Those results suggest that the Heinrich events involved important changes in ocean-atmosphere circulation, and thus forcing other than internal …

Seawifs Satellite Ocean Color Data From The Southern Ocean, Jk Moore, Mr Abbott, Rg Richman, Walker O. Smith Jr., Et Al

VIMS Articles

SeaWiFS estimates of surface chlorophyll concentrations are reported for the region of the U.S. JGOFS study in the Southern Ocean (similar to 170 degrees W, 60 degrees S). Elevated chlorophyll was observed at the Southern Ocean fronts, near the edge of the seasonal ice sheet, and above the Pacific-Antarctic Ridge. The elevated chlorophyll levels associated with the Pacific-Antarctic Ridge are surprising since even the crest of the ridge is at depths > 2000 m. This elevated phytoplankton biomass is likely the result of mesoscale physical-biological interactions where the Antarctic Circumpolar Current (ACC) encounters the ridge. Four cruises surveyed this region between …

Characterization Of Hypoxia: Topic 1 Report For The Integrated Assessment On Hypoxia In The Gulf Of Mexico, Nancy N. Rabalais, R. Eugene Turner, Dubravko Justic, Quay Dortch, William J. Wiseman

Faculty Publications

No abstract provided.

Close-Range And Satellite Remote Sensing Of Algal Biomass In The Iowa Great Lakes, Eric A. Wilson

Department of Geography: Dissertations, Theses, and Student Research

The utility of both close-range and satellite remote sensing for assessing inland water quality was examined in the Iowa Great Lakes. The water quality of this system is of considerable interest because of its status as an environmental, recreational, and therefore, economic resource. The broad range of optical conditions present in the lakes and the wealth of literature on the system make it an ideal environment for water quality remote sensing research. The goal of this research was to survey the water quality of the Iowa Great Lakes via remote sensing, evaluate different predictive algorithms, and map the distribution of …

Poc Production And Export In The Indian Ocean Sector Of The Southern Ocean: A Us-China Collaborative Research Program, Cynthia H. Pilskaln, Fei Chai

University of Maine Office of Research Administration: Grant Reports

This proposed work is a study of the biological production and export flux of biogenic matter in response to ventilation of intermediate and deep water masses within the Polar Front zone. It is a collaborative work between the University of Maine and the Chinese Antarctic Research Expedition (CHINARE). The shipboard work is proposed for the Chinese antarctic resupply vessel off Prydz Bay in the Indian Ocean sector. In the austral Spring, this region experiences phytoplankton blooms that are thought to be the result of nutrient transport by the ventilation of intermediate and deep water masses. On an annual basis, it …

Nutrient Enhanced Coastal Ocean Productivity In The Northern Gulf Of Mexico, William J. Wiseman Jr., Michael J. Dagg, Nancy N. Rabalais, Terry E. Whitledge

Faculty Publications

No abstract provided.

Gravity Wave Characteristics In The Lower Atmosphere At South Pole, Matt Pfenniger, Alan Z. Liu, George C. Papen, Chester S. Gardner

Physical Sciences - Daytona Beach

A 4-year (1993-1996) temperature and wind data set obtained from over 2000 high-resolution balloon soundings at South Pole is used to study gravity wave characteristics in the atmosphere and lower stratosphere. Extensive analyses of energy density, spectra, and static stability are performed to present a comprehensive view of the gravity waves are ubiquitous and often fairly strong at the South Pole, even though the generation mechanisms are not clear. Gravity wave characteristics are, in general, similar to those obtained at other high-latitude southern hemisphere stations. Potential energies vary between about 0.5 J/kg and 5 J/kg with season and altitude. Variations …

Spatial Variability Of Climate And Past Atmospheric Circulation Patterns From Central West Antarctic Glaciochemistry, David B. Reusch, Paul Andrew Mayewski, Sallie I. Whitlow, Iqbal I. Pittalawa, Mark S. Twickler

Earth Science Faculty Scholarship

Atmospheric circulation patterns and the spatial variability of atmospheric chemistry and moisture transport in central West Antarctica are investigated using new 40 year long (1954–1994 A.D.) glaciochemical and accumulation rate records developed from four firn cores from this region. The core sites lie on a 200 km traverse from 82° 22′ S, 119° 17′ W to 81° 22′ S, 107° 17′ W. The glaciochemical records represent the major ionic species present in Antarctic snow: Na⁺, K⁺, Mg²⁺, Ca²⁺, Cl⁻, NO₃⁻, and SO₄²⁻. High spatial …

Aerosol Chemical Composition And Distribution During The Pacific Exploratory Mission (Pem) Tropics, Jack E. Dibb, R. Talbot, Eric Scheuer, D R. Blake, N J. Blake, G L. Gregory, G W. Sachse, D C. Thornton

Earth Sciences

Distributions of aerosol-associated soluble ions over much of the South Pacific were determined by sampling from the NASA DC-8 as part of the Pacific Exploratory Mission (PEM) Tropics campaign. The mixing ratios of all ionic species were surprisingly low throughout the free troposphere (2-12 km), despite the pervasive influence from biomass burning plumes advecting over the South Pacific from the west during PEM-Tropics. At the same time, the specific activity of 7Be frequently exceeded 1000 fCi m-3 through much of the depth of the troposphere. These distributions indicate that the plumes must have been efficiently scavenged by precipitation (removing the …

Influence Of Biomass Combustion Emissions On The Distribution Of Acidic Trace Gases Over The Southern Pacific Basin During Austral Springtime, R. Talbot, Jack E. Dibb, Eric Scheuer, D R. Blake, N J. Blake, G L. Gregory, G W. Sachse, J D. Bradshaw, S T. Sandholm, H B. Singh

Earth Sciences

This paper describes the large-scale distributions of HNO₃, HCOOH, and CH₃COOH over the central and South Pacific basins during the Pacific Exploratory Mission-Tropics (PEM-Tropics) in austral springtime. Because of the remoteness of this region from continental areas, low part per trillion by volume (pptv) mixing ratios of acidic gases were anticipated to be pervasive over the South Pacific basin. However, at altitudes of 2–12 km over the South Pacific, air parcels were encountered frequently with significantly enhanced mixing ratios (up to 1200 pptv) of acidic gases. Most of these air parcels were centered in the 3–7 …

Evidence Of Nox Production Within Or Upon Ice Particles In The Greenland Snowpack, R E. Honrath, Matthew C. Peterson, S Guo, Jack E. Dibb, P B. Shepson, Bradley M. Campbell

Earth Sciences

NOx and NOy were determined in the interstitial air of surface snow and in ambient air at Summit, Greenland. NOx levels in interstitial air were 3 to >10 times those in ambient air, and were generally greater than ambient NOy levels. [NOy] in interstitial air varied diurnally in a manner consistent with photochemical generation within the snowpack. These observations imply that photochemical reactions occurring within or upon the ice crystals of surface snow produced NOx from a N-reservoir compound within the snow. Average [NOX]:[HNO3] and [NOx]:[NOy] ratios in ambient air above the snow were elevated relative to other remote sites, …

Three Dimensional Hydrodynamic-Sedimentation Modeling Study : Hampton Roads Crossing, Lower James River, Virginia, John D. Boon, Harry V. Wang, S. C. Kim, Albert Y. Kuo, G. M. Sisson

Reports

A three-dimensional hydrodynamic-sedimentation computer model, HYSED-3D, was used to evaluate the effect of bridge-tunnel infrastructure for a proposed highway crossing of Hampton Roads on the physical characteristics (tides, currents, circulation, salinity, and sedimentation) of the James River estuary in Virginia. Model-represented infrastructure included tunnel islands and bridges on pilings connecting the islands to interstate highways in Newport News, Hampton, Norfolk, and Portsmouth, Virginia. Combinations of these elements occur in each of three proposed crossing routes designated Alternative 1 (Hampton-Norfolk), Alternative 2 (Hampton-Norfolk, Norfolk-Portsmouth), and Alternative 9 (Newport News-Portsmouth-Norfolk). Simulation comparisons were made between the existing waterways and infrastructure in Hampton …

A Note On Gravity Wave-Driven Volume Emission Rate Weighted Temperature Perturbations Inferred From O₂ Atmospheric And O I 5577 Airglow Observations, Michael P. Hickey Ph.D., Richard L. Walterscheid

Publications

A full-wave dynamical model and chemistry models that simulate ground-based observations of gravity wave-driven O₂ atmospheric and O I 5577 airglow fluctuations in the mesopause region are used to demonstrate that for many observable gravity waves modeling is required to infer temperature perturbation amplitudes from airglow observations. We demonstrate that the amplitude of the altitude-integrated volume emission rate weighted temperature perturbation differs by at least about 30% from the amplitude of the temperature perturbation of the major gas in the vicinity of the peak of the airglow volume emission rate for gravity waves with horizontal phase speeds less than about …

Crop Updates 1999 - Cereals, Len W. Broadbridge, Doug Abrecht, D. Bakker, Greg Hamilton, Cliff Spann, Doug Rowe, Peter Fisher, Jennifer Bignell, Matthew Braimbridge, Bill Bowden, Ross Brennan, Reg Lunt, Senthold Asseng, Cherie Rowles, Simon Bedbrook, Chris Gazey, Mike Bolland, Garren Knell, Lyn Abbott, Zed Rengel, Wayne Pluske, Erin Cahill, Bill Crabtree, Matthew Evans, Tim Nielsen, Jat Bhathal, Rob Loughman, D. Rasmussen, Roger Jones, Sean Kelly, Ian Riley, Sharyn Tayor, Vivien Vanstone, Dominie Wright, Debbie Thackray, Simon Mckirdy, George Yan, Robin Wilson, Iain Barclay, Robin Mclean, Dean Diepeveen, Bill Lambe, Wal Anderson, Brenda Shackley, Mechelle Owen, Peter Burgess, Ben Curtis, Mohammed A. Hamza, Jamie Henderson, Frank Boetel, Alfredo Impiglia, Frances Hoyle, Darshan Sharma, Pierre Fievez, Blakely Paynter, Glen Mcdonald, Kevin Young, Andrew Blake, Keith Devenish, Perry Dolling, Roy Latta, Lisa-Jane Blacklow, Chris Matthews, Angelo Loi, Brad Nutt, Rochelle Mcrobb, David Webb, Andrew Mcrobb, Clinton Revell, James Ridsdill-Smith, Celia Pavri, David Tennant, Darryl Mclements, Ross Thompson, Mike Ewing, Tim Woodburn, Paul Yeoh, James Fisher, Art Diggle, Mark Whitten, Andrew Rate, Paul Carlile, Ed Blanchard, Bevan Buirchell, Lorraine Osborne, Tress Walmsley, Terry Piper, Cameron Weeks, Michael Dodd, Amanda Falconer, Caroline Peek, Glenn Adam, Camray Gethin, Richard Guinness, Daniel Fels, Andrew Rintoul, Mal Lamond, Roger Tapp, Craig White

Crop Updates

This article covers sixty papers

FOREWORD

ACKNOWLEDGMENTS

PLENARY PAPERS

1. Western Australia’s climate: trends and opportunities, Len W. Broadbridge, Director, Bureau of Meterorology

2. Managing seasonal variations in agriculture, Dr Doug Abrecht, Director, Dryland Research Institute, Merredin

CROP ESTABLISHMENT

3. Soil management to prevent waterlogging on duplex soils in the Great Southern, D. Bakker, Greg Hamilton, Cliff Spann and Doug Rowe, Agriculture Western Australia

4. The influence of no-till and press wheels on crop production for heavy soils, Peter Fisher, Jennifer Bignell, Matthew Braimbridge, Greg Hamilton, Agriculture

Western Australia

NUTRITION

5. Fertiliser nitrogen, applied late, needs …

Holocene Climate In Coastal Peru: Potential Implications For Climate Dynamics During The Hypsithermal Period, James D. Wright

University of Maine Office of Research Administration: Grant Reports

This pilot study will analyze stable isotopes in planktic foraminifera in sediment cores off the coast of Peru for the Holocene interval. In many regions of the world the early Holocene is believed to have been a time of warmer-than modern temperatures. Data derived from Peruvian middens give conflicting evidence as to whether this period was somewhat warmer or cooler than today. The foraminiferal data should provide a record of sea surface temperatures and seasonal upwelling along coastal Peru throughout the Holocene, including the period of human coastal settlement.

Announcements: February 1999

Drought Network News (1994-2001)

Contents:

International Symposium on High Altitude and Sensitive Ecological Environmental Geotechnology

5th International Symposium on Environmental Geotechnology and Global Sustainable Development

10th Global Warming International Conference & Expo (GW10)

New Book

Rainfall Climatology Of Jammu And Kashmir State, India, Badrul Hasan

Drought Network News (1994-2001)

We have written a number of articles on various aspects of weather characterization and forecast verification under temperate environments of Jammu and Kashmir (India). We have also touched on some of the approaches that might help in solving climatically triggered problems (Hasan and Kanth 1997). Fortunately, we were lucky enough to make significant progress in some (if not all) of the approaches. The present article focuses on an analysis of rainfall/ precipitation in this state of the Indian Union under different agroclimatic zones, with an update on forecast verification analysis of temperate Kashmir (India) during 1997–98.

India is classified into …

Using The Spi To Analyze Spatial And Temporal Patterns Of Drought In Turkey, Ali Umran Komuscu

Drought Network News (1994-2001)

Drought is a natural phenomenon that has significant economic, social, and environmental impacts. Drought differs from other natural hazards in that its onset and end are difficult to determine. It develops slowly, and its impacts may remain for years after termination of the event. No single definition of drought exists that applies to all circumstances, but most definitions of drought are based on an expression of deficiency of precipitation resulting in water shortage for some activity related to use of water (Wilhite and Glantz, 1985; Dracup et al., 1980). Water resources planners usually rely on quantitative indices to decide whether …

Heat Waves And Floods Across Asia: Was El Niño, Then La Niña The Cause?, R. H. Kripalani, Ashwini Kulkarni

Drought Network News (1994-2001)

Unprecedented heat wave conditions occurred during May–June 1998 across Asia. Unusually high temperatures were recorded in western India, Pakistan, eastern China, Japan, and Southeast Asia. Even the United States, western Africa, eastern Canada, and western Australia experienced the blistering heat spell.

Some reports blame people for the global warming. The world is warming because of the burning of fossil fuels and deforestation, resulting in an increase in carbon dioxide in the atmosphere. The 1998 heat wave prompted the United Nations Environment Programme to issue an urgent warning and a wakeup call to limit the emission of global warming gases. The …

Severe Droughts Becoming Recurrent, More Persistent In Mexico, Israel Velasco

Drought Network News (1994-2001)

During recent years, severe and extreme droughts in Mexico and their consequent water deficits have become more recurrent and persistent, according to historic records and the experiences of those who have lived through these events.

In Mexico, agriculture consumes more than 85% of the available water. When the available water is insufficient to satisfy agricultural requirements, impacts can be acute. In extreme cases, lack of water has caused severe economic, social, and environmental crises, and recovery from these crises has taken much time and money.

The regions that are most affected by drought have some common characteristics: they are the …

From The Director: February 1999, Donald A. Wilhite

Drought Network News (1994-2001)

Many of the readers of Drought Network News are familiar with the “hydro-illogical cycle” cartoon that I use frequently in presentations and publications. This illustration has been translated into many languages and serves as a constant reminder of the crisis management mentality often displayed in responding to drought emergencies and the proverbial “window of opportunity” following a drought when planning for the next event is of high priority. I hear comments routinely from government officials that recognize the need to plan, but they express hesitancy in moving forward now if water supply conditions are normal or above. The concern is …

Arizona Source Water Assessment Plan Final Draft, Arizona Department Of Environmental Quality

Publications (WR)

The safe drinking water amendments of 1996 placed a strong emphasis on the goal to establish a nationwide effort to protect drinking water sources. As part of that goal, the legislation provided for a preliminary assessment of drinking water sources and an inventory of surrounding adjacent land use (ALUs). This nationwide effort will result in the first comprehensive look at the nation's drinking water sources from an assessment perspective. One of the outcomes of this nationwide assessment will be information that public water systems (PWSs) can use to help determine appropriate monitoring frequencies and to protect their sources of drinking …

Guide For Developing Integrated Aquatic Vegetation Management Plans In Oregon, Maribeth Gibbons, Mark Rosenkranz, Harry L. Gibbons, Mark Sytsma

Center for Lakes and Reservoirs Publications and Presentations

This manual focuses on controlling nuisance aquatic plants, occurring in Oregon lakes. To use this manual, it is necessary to distinguish between an aquatic plant problem, and a water quality enrichment problem that typically results in excessive algae production (See Box this page). The most serious type of aquatic plant problem is caused by invasion of a waterbody by a non-native species. Non-native weed invaders may flourish in suitable conditions and degrade habitat and other beneficial uses. The biology and ecology of weeds allows them to fluorish under a wide range of conditions. Nutrient enrichment is not a prerequisite for …

1999 Gloucester Point Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.

Climatological Significance Of Δ18O In Precipitation And Ice Cores: A Case Study At The Head Of The Ürütnqi River, Tien Shan, China, Hou Shugui, Qin Dahe, Paul Andrew Mayewski, Yang Qinzhao, Ren Jiawen, Li Zhongqin, Xiao Cunde

Earth Science Faculty Scholarship

Stable-oxygen-isotope ratios (δ¹⁸O) collected from the headwaters of the Ürümqi river, Tien Shan, China, were used to test the relationship between δ¹⁸O temporal relationship is found between δ¹⁸O monthly averages which remove synoptic-scale influences such as changes in condensation level, condensation temperature and moisture sources (Yao and others, 1996). Linear fits as high as 0.95‰°C^-1 for precipitation events and 1.23‰°C^-1 for monthly averages are found. Although the δ¹⁸O (∼2 km from the precipitation sampling site) decreased dramatically compared to the precipitation samples , the ice-core records of annually averaged δ …

Analyzing Mean Transport Equations Of Turbulence And Linear Disturbances In Decaying Flows, W. D. Thacker, T. B. Gatski, C. E. Grosch

CCPO Publications

The decay of laminar disturbances and turbulence in mean shear-free flows is studied. In laminar flows, such disturbances are linear superpositions of modes governed by the Orr-Sommerfeld equation. In turbulent flows, disturbances are described through transport equations for representative mean quantities. The link between a description based on a deterministic evolution equation and a probability-based mean transport equation is established. Because an uncertainty in initial conditions exists in the laminar as well as the turbulent regime, a probability distribution must be defined even in the laminar case. Using this probability distribution, it is shown that the exponential decay of the …

An Iron-Based Ecosystem Model Of The Central Equatorial Pacific, Carrie L. Leonard, Charles R. Mcclain, Ragu Murtugudde, Eileen E. Hofmann, Lawrence W. Harding Jr.

CCPO Publications

The central and eastern equatorial Pacific region is characterized by lower than expected phytoplankton biomass and primary production given the relatively high ambient nitrate concentrations. These unusual conditions have spawned several field programs and laboratory experiments to determine why this high nitrate-low chlorophyll pattern persists in this region. To synthesize the results from these field programs, as well as providing additional evidence in support of the iron hypothesis, we developed a one-dimensional, nine-component ecosystem model of 0 degrees N 140 degrees W. The model components include two phytoplankton size fractions, two zooplankton size fractions, two detrital size fractions, dissolved iron, …

Frontogenesis In The North Pacific Oceanic Frontal Zones--A Numerical Simulation, Michael S. Dinniman, Michele M. Rienecker

CCPO Publications

A primitive equation model [Geophysical Fluid Dynamics Laboratory's (GFDL's) MOM 2] with one degree horizontal resolution is used to simulate the seasonal cycle of frontogenesis in the subarctic frontal zone (SAFZ) and the subtropical frontal zone (STFZ) of the North Pacific Ocean. The SAFZ in the model contains deep (greater than 500 m in some places) regions with seasonally varying high gradients in temperature and salinity. The gradients generally weaken toward the east. The STFZ consists of a relatively shallow (less than 200 m in most places) region of high gradient in temperature that disappears in the summer/fall. The high …