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Regional Variation In Recruitment Of Hemlock Seedlings And Saplings In The Upper Great Lakes, Usa, Thomas P. Rooney, Ronald J. Mccormick, Stephen L. Solheim, Donald M. Waller Aug 2000

Regional Variation In Recruitment Of Hemlock Seedlings And Saplings In The Upper Great Lakes, Usa, Thomas P. Rooney, Ronald J. Mccormick, Stephen L. Solheim, Donald M. Waller

Biological Sciences Faculty Publications

Mature eastern hemlock–northern hardwood forest cover decreased drastically in the upper Midwest following European settlement and has yet to rebound substantially. Previous studies show that stands retaining substantial hemlock canopy coverage have low hemlock seedling and sapling densities. Results from various geographically restricted studies suggest several possible mechanisms that could cause low seedling or sapling density. We examined the relative importance of these proposed mechanisms in the Southern Superior Uplands Section of the Laurentian Forest Province. We surveyed 294- m2 plots in 100 hemlock stands in northern Wisconsin and western upper Michigan to assess how these proposed mechanisms affect the …


Sequences Of Citrus Tristeza Virus Separated In Time And Space Are Essentially Identical, Maria R. Albiach-Marti, Munir Mawassi, Siddarame Gowda, Satyanarayana Tatineni, Mark E. Hilf, Savita Shanker, Ernesto C. Almira, Maria C. Vives, Carmelo Lopez, Jose Guerri, Ricardo Flores, Pedro Moreno, Steve M. Garnsey, William O. Dawson Aug 2000

Sequences Of Citrus Tristeza Virus Separated In Time And Space Are Essentially Identical, Maria R. Albiach-Marti, Munir Mawassi, Siddarame Gowda, Satyanarayana Tatineni, Mark E. Hilf, Savita Shanker, Ernesto C. Almira, Maria C. Vives, Carmelo Lopez, Jose Guerri, Ricardo Flores, Pedro Moreno, Steve M. Garnsey, William O. Dawson

Department of Plant Pathology: Faculty Publications

The first Citrus tristeza virus (CTV) genomes completely sequenced (19.3-kb positive-sense RNA), from four biologically distinct isolates, are unexpectedly divergent in nucleotide sequence (up to 60% divergence). Understanding of whether these large sequence differences resulted from recent evolution is important for the design of disease management strategies, particularly the use of genetically engineered mild (essentially symptomless)-strain cross protection and RNA-mediated transgenic resistance. The complete sequence of a mild isolate (T30) which has been endemic in Florida for about a century was found to be nearly identical to the genomic sequence of a mild isolate (T385) from Spain. Moreover, samples of …


Identifying Areas Of Agricultural Significance, Ian Kininmonth Aug 2000

Identifying Areas Of Agricultural Significance, Ian Kininmonth

Agriculture reports

The protection of productive agricultural land and the avoidance of land use conflicts in rural areas are important objectives of the Western Australian Government. They are reflected in the State Planning Strategy, Agriculture Western Australia’s strategic plan, ‘Focus on the Future’ and draft Statement of Planning Policy (SPP) No. 11 – Agricultural and Rural Land Use Planning Policy. However, agricultural land is required for a variety of purposes and so it is important that agriculture is able to identify those areas which are irreplaceable in terms of existing and future production and those areas which may be used for other …


Kentucky Salamanders Of The Genus Desmognathus: Their Identification, Distribution, And Morphometric Variation, Leslie Scott Meade Jul 2000

Kentucky Salamanders Of The Genus Desmognathus: Their Identification, Distribution, And Morphometric Variation, Leslie Scott Meade

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Leslie Scott Meade on July 24, 2000.


A New Species Of Angulopis (Lycaenidae, Eumaeini) From Relict Coastal Forest In East-Central Argentina, Gustavo Canals, Kurt Johnson Jul 2000

A New Species Of Angulopis (Lycaenidae, Eumaeini) From Relict Coastal Forest In East-Central Argentina, Gustavo Canals, Kurt Johnson

The Taxonomic Report of the International Lepidoptera Survey

Angulopis puntalaraensis is described from a single female specimen collected between 1950 and 1955 in the National Reserve Punta Lara, Buenos Aires Province, Argentina. This site is a relict of coastal gallery forest. No other specimens are known.


Description Of A New Subspecies Of Poanes Aaroni (Hesperioidae: Hesperiinae) From The West Central Gulf Coast Of The Southern United States, Ronald R. Gatrelle Jul 2000

Description Of A New Subspecies Of Poanes Aaroni (Hesperioidae: Hesperiinae) From The West Central Gulf Coast Of The Southern United States, Ronald R. Gatrelle

The Taxonomic Report of the International Lepidoptera Survey

Poanes aaroni bordeloni is described from Jefferson County, Texas, United States. This taxon is part of a lepidopteran community endemic to the west central area of the United States Gulf Coast between Mobile Bay, Alabama and Galveston Bay, Texas. As such, bordeloni is defined taxonomically by its evolutionary development as much as by its facies. Bordeloni is the largest aaroni subspecies. Bordeloni males are marked much like those of P. a. howardi both dorsally and ventrally. Bordeloni females usually have the fulvous spotting on the dorsal forewings reduced as in P. a. minimus females while …


The Impacts Of The Introduced European Green Crab, Carcinus Maenas, On Selected Bivalves And Meiofaunal Communities, Zasha A. Bassett Jul 2000

The Impacts Of The Introduced European Green Crab, Carcinus Maenas, On Selected Bivalves And Meiofaunal Communities, Zasha A. Bassett

Dissertations and Theses

This thesis examines the potential impact of the invasive green crab, Carcinus maenas, in Yaquina Bay, Oregon. I sampled the current extent of crab colonization in the intertidal zone of Yaquina Bay using a standardized trapping regimen in selected intertidal sites in August and September 1999. I also evaluated the potential impacts of C. maenas on the commercially important bivalve, Crassotrea gigas. Carcinus' preferred size ranges of C. gigas and other species were experimentally determined. Additionally, Carcinus species preference for C. gigas was examined in relation to two common bivalves, Mytilus trossolus and Macoma nasuta. Experiments were …


Key Trends In Population And Land Use In The West, William E. Riebsame Jun 2000

Key Trends In Population And Land Use In The West, William E. Riebsame

Water and Growth in the West (Summer Conference, June 7-9)

9 pages (includes illustrations and maps).

Contains 1 page of references.


Agenda: Water And Growth In The West, University Of Colorado Boulder. Natural Resources Law Center, The William And Flora Hewlett Foundation Jun 2000

Agenda: Water And Growth In The West, University Of Colorado Boulder. Natural Resources Law Center, The William And Flora Hewlett Foundation

Water and Growth in the West (Summer Conference, June 7-9)

1 v. (various pagings) : ill., maps ; 29 cm. + 1 CD-ROM (4 3/4 in.) + supplement (207 p. ; 29 x 24 cm.)

"Conference co-sponsor The William and Flora Hewlett Foundation."

Conference moderators included University of Colorado School of Law professors Gary C. Bryner, James N. Corbridge, Jr., David H. Getches, Douglas S. Kenney, Kathryn M. Mutz, Peter D. Nichols and Charles F. Wilkinson.

Accompanied by: CD-ROM (4 3/4 in.) and supplement (xiv, 140, [49] p.)

Includes bibliographical references

The event will cover a breadth of issues, including demographics and water-use trends, improved planning and efficient use, implementation …


Parasite Community Structure In Pimephales Promelas (Pisces: Cyprinidae) From Two Converging Streams, M. A. Weichman, John A. Janovy Jr. Jun 2000

Parasite Community Structure In Pimephales Promelas (Pisces: Cyprinidae) From Two Converging Streams, M. A. Weichman, John A. Janovy Jr.

John J. Janovy, Jr. Publications

Parasites of the fathead minnow, Pimephales promelas, were examined in fish collected from Elk Creek (40.88534°N, 96.83366°W) and West Oak Creek (40.90821°N, 96.81432°W), Lancaster County, Nebraska. These two streams are part of the Salt Valley watershed and flow together approximately 2 km downstream from the collection sites to form Oak Creek. This study examined the extent to which the two tributaries constitute a continuous habitat with respect to fish hosts. The parasite community included Trichodina sp., Myxobolus sp., Dactylogyrus simplex, D. bychowskyi, and D. pectenatus (all on gills); Gyrodactylus hoffmani (gill and body surface); Posthodiplostomum sp. (neascus, body …


Cutting Your Timberland Taxes, May 19-20, 2000, Arthur Temple College Of Forestry And Agriculture May 2000

Cutting Your Timberland Taxes, May 19-20, 2000, Arthur Temple College Of Forestry And Agriculture

eBooks

No abstract provided.


Efficacy, Phytotoxicity, And Cover Crop Response Of Herbicide Combinations In Dark Fire Cured Tobacco, Tracy Kelley May 2000

Efficacy, Phytotoxicity, And Cover Crop Response Of Herbicide Combinations In Dark Fire Cured Tobacco, Tracy Kelley

Masters Theses & Specialist Projects

Field studies were established during the summer of 1999 at the Agricultural Research and Education Complex of Western Kentucky University to evaluate efficacy, phytotoxicity, and cover crop response of herbicide combinations in dark fire cured tobacco. A randomized complete block design was used with nine treatments replicated three times. Hydroponic tobacco transplants (c.v. 'TND950') were established on May 20,1999 in a conventionally tilled system on a Pembroke silt loam (Mollic Palleudalf) with a pH of 5.8 and an organic matter content of 1.2%. The transplants were established at a population of approximately 10,278 plants/ha. Herbicide treatments were applied on May …


The Age Of The Woolly Rhino From Dream Cave, Derbyshire, Uk, Donald A. Mcfarlane, Joyce Lundberg, Derek C. Ford Apr 2000

The Age Of The Woolly Rhino From Dream Cave, Derbyshire, Uk, Donald A. Mcfarlane, Joyce Lundberg, Derek C. Ford

WM Keck Science Faculty Papers

The Dream Cave woolly rhinoceros, Coelodonta antiquitatis, is a "classic" specimen of a "cold-stage" fossil fauna from central England. The find was illustrated and described by Dean William Buckland in his seminal tome Reliquiae Diluvianae (1823) during the first half of the 19th century, and made a significant contribution to the development of Buckland's views on the origin of extinct and extirpated fossil vertebrates. The report presents the first, albeit indirect, radiometric dates on the specimen, and argues that the animal fell into the cave just before 37,000 years BP, during the middle of Marine Isotope Stage 3 Interstadial (41 …


Molecular Taxonomy Of The Lichen Genus Heterodermia, Linda Hirschberger Apr 2000

Molecular Taxonomy Of The Lichen Genus Heterodermia, Linda Hirschberger

Seton Hall University Dissertations and Theses (ETDs)

Heterodermia is lichen consisting of a fungus and algae. Morphology and chemistry cannot provide definitive evidence for the identity of Heterodermia because various species have very similar morphologies that cannot always be distinguished. Other species only differ by the presence or absence of secondary chemicals detected. by specific chemical tests, which makes distinguishing between two species difficult. The objective of this project is to use Restriction Fragment Length Polymorphisms (RFLPs) to determine how closely related each Heterodermia species is to one another. RFLPs will also be used to determine how closely related a species is to its equal in another …


Multiple Source Pools And Dispersal Barriers For Galápagos Plant Species Distribution, J. Alan Yeakley, John F. Weishampel Apr 2000

Multiple Source Pools And Dispersal Barriers For Galápagos Plant Species Distribution, J. Alan Yeakley, John F. Weishampel

Environmental Science and Management Faculty Publications and Presentations

We reexamined geographic factors explaining the number of plant species on islands in the Galápagos Archipelago. We hypothesized that plant species richness (S) was related to the number of source pools and that plant species dispersal preferentially followed direct, oceanic pathways. To test different dispersal pathways from multiple source pools, the total number of islands within a given dispersal radius (i) was posed as the sum of the number of line-of-sight islands (Ci) and of the number of islands without line-of sight connection (Bi). In partial regression analyses, controlling for nearest island area (A2) …


Effects Of The Zebra Mussel On Nitrogen Dynamics And The Microbial Community At The Sediment-Water Interface, Peter J. Lavrentyev, Wayne S. Gardner, Longyuan Yang Mar 2000

Effects Of The Zebra Mussel On Nitrogen Dynamics And The Microbial Community At The Sediment-Water Interface, Peter J. Lavrentyev, Wayne S. Gardner, Longyuan Yang

Biology Faculty Research

A flow-through experiment was conducted on intact cores of sediments from Saginaw Bay, Lake Huron, to examine how trophic interactions between filter-feeding bivalve mussels and microbial populations could affect nitrogen dynamics at the sediment-water interface. The zebra mussels used in this experiment removed a large proportion of protozoa and phytoplankton from the overlying water, particularly heterotrophic nanoplankton (up to 82%), while bacterial populations showed less change. A 3-fold decrease in the protozoan to bacterial carbon ratio corresponded to a 2.5-fold increase in relative ammonium removal rates as estimated from the dark loss of N-15-ammonium. Excretion by the bivalves also increased …


Modeling The Growth Dynamics Of Antarctic Krill Euphausia Superba, Eileen E. Hofmann, Cathy M. Lascara Mar 2000

Modeling The Growth Dynamics Of Antarctic Krill Euphausia Superba, Eileen E. Hofmann, Cathy M. Lascara

CCPO Publications

A time-dependent, size-structured, bioenergetically based model was developed to examine the growth dynamics of Antarctic krill Euphausia superba 2 to 60 mm in size. The metabolic processes included in the model are ingestion, a baseline respiration, respiratory losses due to feeding and digestion, and an activity-based respiration factor. The total of these processes, net production, was used as the basis for determining the growth or shrinkage of individuals. Size-dependent parameterizations for the metabolic processes were constructed from field and laboratory measurements. Environmental effects were included through time series of pelagic phytoplankton concentration that were derived from data sets collected west …


Trends In Retailing Activity Across Nebraska, Bruce B. Johnson, Brandon Raddatz Feb 2000

Trends In Retailing Activity Across Nebraska, Bruce B. Johnson, Brandon Raddatz

Cornhusker Economics

The structural trend in production agriculture towards fewer and larger farms has had its counter-part in the retailing sector of the state as well. Over the past 30 years, the total retailing pie has increasingly shifted to the larger retailing centers across the State. The smaller retailing centers, particularly, have experienced greater retailing leakage. Moreover, these general shifts have seemed to continue unabated regardless of the overall economic conditions of their regions.


Wpa News 61 (2000), World Pheasant Association Feb 2000

Wpa News 61 (2000), World Pheasant Association

Galliformes Specialist Group and Affiliated Societies: Newsletters

WPA News (February 2000), number 61

Published by the World Pheasant Association


Genetic Variation Among Endosymbionts Of Widely Distributed Vestimentiferan Tubeworms, Carol A. Di Meo, Ami E. Wilbur, William E. Holben, Robert A. Feldman, Robert C. Vrijenhoek, S. Craig Cary Feb 2000

Genetic Variation Among Endosymbionts Of Widely Distributed Vestimentiferan Tubeworms, Carol A. Di Meo, Ami E. Wilbur, William E. Holben, Robert A. Feldman, Robert C. Vrijenhoek, S. Craig Cary

Biological Sciences Faculty Publications

Vestimentiferan tubeworms thriving in sulfidic deep-sea hydrothermal vents and cold seeps are constrained by their nutritional reliance on chemoautotrophic endosymbionts. In a recent phylogenetic study using 16S ribosomal DNA, we found that endosymbionts from vent and seep habitats form two distinct clades,vith little variation within each clade. In the present study, we used two different approaches to assess the genetic variation among biogeographically distinct vestimentiferan symbionts, DNA sequences were obtained for the noncoding, internal transcribed spacer (ITS) regions of the rRNA operons of symbionts associated with six different genera of vestimentiferan tubeworms. ITS sequences from endosymbionts of host genera collected …


Estimating Animal Abundance Using Noninvasive Dna Sampling: Promise And Pitfalls, L. Scott Mills, J. J. Ciatta, K. P. Lair, M. K. Schwartz, D. A. Tallmon Feb 2000

Estimating Animal Abundance Using Noninvasive Dna Sampling: Promise And Pitfalls, L. Scott Mills, J. J. Ciatta, K. P. Lair, M. K. Schwartz, D. A. Tallmon

Wildlife Biology Faculty Publications

Advances in molecular biology offer promise to the study of demographic characteristics of rare or hard-re-capture species, because individuals can now be identified through noninvasive sampling such as fecal collection or hair snags. However, individual genotyping using such methods currently leads to a novel problem that we call a "shadow effect," because some animals not captured previously are believed to be recaptures due to their DNA profile being an indistinguishable shadow of previously captured animals. We evaluate the impact of the shadow effect on the two methods most commonly used in applied population ecology to estimate the size of closed …


A Phylogenetic Hypothesis For Species Of The Genus Taenia (Eucestoda: Taeniidae), Eric P. Hoberg, Arlene Jones, Robert L. Rausch, Keeseon S. Eom, Scott Lyell Gardner Feb 2000

A Phylogenetic Hypothesis For Species Of The Genus Taenia (Eucestoda: Taeniidae), Eric P. Hoberg, Arlene Jones, Robert L. Rausch, Keeseon S. Eom, Scott Lyell Gardner

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Cladistic analysis of a numerical data matrix describing 27 characters for species of Taenia resulted in four most parsimonious phylogenetic trees (174 steps; consistency index = 0.28; homoplasy index = 0.72; retention index = 0.48). Monophyly for Taenia is diagnosed by the metacestode that is either a cysticercus or a form derived from a bladder-like larva; no other unequivocal synapomorphies are evident. Tree structure provides no support for recognition of a diversity of tribes or genera within the Taeniinae: Fimbriotaeniini and Taeniini have no phylogenetic basis. Hydatigera, Fimbriotaenia, Fossor, Monordotaenia, Multiceps, Taeniarhynchus, Tetratirotaenia must …


Frequency Of Use And Perceived Credibility Of Information Sources And Variations By Socioeconomic Factors Among Savannah River Stakeholders, Bryan L. Williams, Alex Vallei, Sylvia Brown, Michael Greenberg Jan 2000

Frequency Of Use And Perceived Credibility Of Information Sources And Variations By Socioeconomic Factors Among Savannah River Stakeholders, Bryan L. Williams, Alex Vallei, Sylvia Brown, Michael Greenberg

RISK: Health, Safety & Environment (1990-2002)

The authors examine the factors effecting credibility of risk communication in the communities surrounding the Savannah River Nuclear Weapons Site.


Wildland Fire In Ecosystems Effects Of Fire On Flora, R. James Ansley, Stephen F. Arno, Brent L. Brock, Patrick H. Brose, James K. Brown, Luc C. Duchesne, James B. Grace, Gerald J. Gottfried, Sally M. Haase, Michael G. Harrington, Brad C. Hawkes, Greg A. Hoch, Melanie Miller, Ronald L. Myers, Marcia G. Narog, William A. Patterson Iii, Timothy E. Paysen, Kevin C. Ryan, Stephen S. Sackett, Dale D. Wade, Ruth C. Wilson Jan 2000

Wildland Fire In Ecosystems Effects Of Fire On Flora, R. James Ansley, Stephen F. Arno, Brent L. Brock, Patrick H. Brose, James K. Brown, Luc C. Duchesne, James B. Grace, Gerald J. Gottfried, Sally M. Haase, Michael G. Harrington, Brad C. Hawkes, Greg A. Hoch, Melanie Miller, Ronald L. Myers, Marcia G. Narog, William A. Patterson Iii, Timothy E. Paysen, Kevin C. Ryan, Stephen S. Sackett, Dale D. Wade, Ruth C. Wilson

Joint Fire Science Program Synthesis Reports

This state-of-knowledge review about the effects of fire on flora and fuels can assist land managers with ecosystem and fire management planning and in their efforts to inform others about the ecological role of fire. Chapter topics include fire regime classification, autecological effects of fire, fire regime characteristics and postfire plant community developments in ecosystems throughout the United States and Canada, global climate change, ecological principles of fire regimes, and practical considerations for managing fire in an ecosytem context.


Limits To Ice Thickness In Iowa During The Late Wisconsinan, Eric C. Brevik Jan 2000

Limits To Ice Thickness In Iowa During The Late Wisconsinan, Eric C. Brevik

Journal of the Iowa Academy of Science: JIAS

Minimum and maximum limits to Des Moines Lobe ice thickness in Iowa during the Late Wisconsinan glaciation are calculated. These limits are based on minimum and maximum ice thickness calculations for the Des Moines Lobe in eastern North Dakota using crustal depression indicated by Lake Agassiz strandlines. Minimum and maximum basal shear stresses for the Des Moines Lobe are calculated by projecting a flow line from the terminus of the Des Moines Lobe back up-ice to the study site in northeastern North Dakota. Ice thickness in Iowa is then calculated with a method that uses the basal shear stress values. …


Life In A Pine Cone, David L. Kulhavy Jan 2000

Life In A Pine Cone, David L. Kulhavy

Faculty Publications

This exercise focuses on a little-known microhabitat -- the pine cone. A pine cone's primary function is, of course, reproduction ... housing the seeds of the next generation of conifer trees. However, pine cones are also the basis of a food web that provides both resources and living space for a wide variety of small arthropod species. The procedure outlined below is designed to examine this microhabitat and compare its community diversity among different species of conifers and habitats.

The exercise is based on a 1985 paper, Life in a Pine Cone, by David L. Kulhavy, Robert S. Baldridge and …


Avian Mortality At Communication Towers: A Review Of Recent Literature, Research, And Methodology, Paul Kerlinger Jan 2000

Avian Mortality At Communication Towers: A Review Of Recent Literature, Research, And Methodology, Paul Kerlinger

United States Fish and Wildlife Service: Publications

A review of the recent literature and research in progress on bird collisions with
communication towers was contracted by the U. S. Fish and Wildlife Service. In the five year period 1995 through 1999, very little research was published or conducted that is relevant to the bird-communication tower collision problem. It seems that since the major reviews of the late 1970s and early 1980s, few researchers and others have been interested in researching the problem. Before 1985, there was an enormous body of literature, mostly anecdotal that has not been examined analytically.

For the current review,, a standard literature search …


Crop Watch No. 2000-10, May 19, 2000, Lisa Brown Jasa Jan 2000

Crop Watch No. 2000-10, May 19, 2000, Lisa Brown Jasa

Crop Watch (1994–2005)

Field Updates..........80

Stalk Borer Scouting..........81

Weeds in Soybeans..........82

Frosted Wheat..........83

Assessing Wheat Damage..........84

Corn Leaf Beetles..........85

Purple Loosestrife..........86

Wheat Diseases/Insects..........88

ECB Light Traps..........88


Index To Volumes 18 And 19 Jan 2000

Index To Volumes 18 And 19

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.


Patterns And Implications Of Aberrant Singing Behaviors Of Black-Capped (Poecile Atricapillus) And Carolina (Poecile Carolinensis) Chickadees In Illinois, Patrick Caesar Enstrom Jan 2000

Patterns And Implications Of Aberrant Singing Behaviors Of Black-Capped (Poecile Atricapillus) And Carolina (Poecile Carolinensis) Chickadees In Illinois, Patrick Caesar Enstrom

Masters Theses

I studied the singing behavior of the closely related Black-capped (Poecile atricapillus) and Carolina (Poecile carolinensis) Chickadees along their range interface in central Illinois. These sibling species are parapatrically distributed from the Appalachians through the Midwest to Kansas. Where their ranges do overlap, small hybrid zones form and chickadees in these areas frequently sing aberrant songs. The majority of the songs studied were recorded 17 April-16 July 1999 in fifteen counties throughout central Illinois. I measured 8 frequency and duration characteristics of the first two notes of songs that began with two whistled notes. The averages of these characteristics …