Life Sciences Commons^™

Ec00-1879 Sorghum Ergot In The Northern Great Plains, Jim Stack

University of Nebraska-Lincoln Extension: Historical Materials

Sorghum is grown throughout Nebraska on approximately 0.6 million acres of land. It is grown as a forage crop as well as a grain crop. There is no significant commercial seed production in Nebraska. Grain sorghum is used domestically as livestock feed, in ethanol production, and to a limited extent as a food crop.

Grain sorghum is also exported to several countries. All sorghum hybrids (grain and forage) are susceptible to ergot disease. Ergot is a disease that impacts sorghum production directly by infecting unfertilized flowers and preventing seed development. Ergot also impacts sorghum production indirectly. Affected fields with honeydew-covered …

Effects Of Diameter-Limit And Two-Age Timber Harvesting On Songbird Populations On An Industrial Forest In Central West Virginia, Cathy Ann Weakland

Graduate Theses, Dissertations, and Problem Reports

Many studies examining forest fragmentation effects on songbirds have been conducted in landscapes significantly altered by urbanization or agriculturalization rather than forested landscapes. There is some evidence that forest fragmentation due to timber harvesting has different effects on bird abundance than fragmentation from other land uses. It is unknown how songbirds respond to different forms of timber harvesting as fragmentation events. Also, it is unclear if microhabitat-level or landscape-level characteristics are more important predictors of breeding bird occurrence in the central Appalachians. The objectives of my study were to determine the short-term effects of diameter-limit and two-age timber harvesting on …

The Reproductive Biology And Edaphic Characteristics Of A Rare, Gynodioecious Saxifage: Saxifraga Bryophora Var. Tobiasiae (Saxifragaceae), Kimberly Pierson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I examined the reproductive biology and general ecology of Saxifraga bryophora var. tobiasiae, a rare saxifrage endemic to the West Salmon River Mountains of central Idaho. Saxifraga bryophora var. tobiasiae combines asexual reproduction via bulbils with a sexual mixed-mating system. Flower production occurred in 1996 only, whereas bulbil production occurred in 1995, 1996, and 1997. Bulbil production precedes floral bud formation and is the dominant form of reproduction. When flowering occurs, outcrossing is promoted by protandry and the gynodioecious mating system found in all populations. No autogamous or agamospermous seed set was observed in either female or hermaphrodite flowers, …

Simulation Of Carbon-Nitrogen Cycling During Spring Upwelling In The Cariaco Basin, John J. Walsh, Dwight A. Dieterle, Frank E. Muller-Karger, Richard Bohrer, W. Paul Bissett, Ramon J. Varela, Ruben Aparicio, Rafael Diaz, Robert Thunell, Gordon T. Taylor, Mary I. Scranton, Kent A. Fanning, Edward T. Peltzer

Marine Science Faculty Publications

Coupled biological-physical models of carbon-nitrogen cycling by phytoplankton, zooplankton, and bacteria assess the impacts of nitrogen fixation and upwelled nitrate during new production within the shelf environs of the Cariaco Basin. During spring upwelling in response to a mean wind forcing of 8 m s(-1), the physical model matches remote-sensing and hydrographic estimates of surface temperature. Within the three-dimensional flow field, the steady solutions of the biological model of a simple food web of diatoms, adult calanoid copepods, and ammonifying/nitrifying bacteria approximate within similar to 9% the mean spring observations of settling fluxes caught by a sediment trap at similar …

Analysis Of Historical Distribution Of Submerged Aquatic Vegetation (Sav) In The James River, Ken Moore, David J. Wilcox, R J. Orth, Eva Bailey

Reports

Analyses of historical photography and ground surveys dating from the 1930s indicate that approximately 1645 hectares of SAV have been historically present in shallow water regions throughout the James River. This compares to 77 hectares of vegetation reported in 1997 and a James River Tier I SAV restoration goal of 107 hectares (areas mappped with SAV from 1971- 1991). Overall, the temporal and spatial patterns of loss of SAV populations in the James River suggest declines occurred first in the tidal freshwater regions of the upper James beginning approximately 50 years ago, and then subsequently in the lower James beginning …

Wolves And Bears: An Interdisciplinary Activity Guide For Grades 3-5, Susan L. Thomas

All Graduate Projects

A popular set of "Discovery Boxes" are used by educators across North Central Washington. These boxes are administered by the U.S. Forest Service and focus on such themes as wolves, bears, fire, plants and forests. These boxes are available to be checked out to educators for two-week periods, and reach approximately 9,000 students annually. Each box contains "hands-on" props which enhance the learning of each theme. Some of the boxes have activity guides in them to assist the educator in teaching the theme and thus using the box to its full potential. Two of the most popular boxes, the wolf …

Observations On The Reproductive Biology Of Gerbillus Dasyurus (Wagner, 1842) (Mammalia: Rodentia) In Turkey, Ercüment Çolak, Mustafa Sözen, Nuri̇ Yi̇ği̇t, Şaki̇r Özkurt

Turkish Journal of Zoology

The reproductive data along with some ecological observations of Gerbillus dasyurus are reported based on field studies and investigations in captivity. The findings indicate that the favorable habitat of G. dasyurus is rocky areas with sparse vegetated soil and that the reproduction period extends from January to September. According to the reproductive data, the average weight at birth is 2.22 g., litter size ranges from 3 to 9, with an average of 5.66, a female gives three litters during a reproduction period. The eyes and ears also open at 16 days, weaning takes place at 32 days, and they become …

The Taxonomy And Ecology Of Mauremys Caspica Rivulatavalenciennes, 1833 (Testudinata: Bataguridae) And Testudo Graeca Ibera Pallas, 1811 (Testudinata: Testudinidae) On Resadiye (Datça) Peninsula, Cemal Varol Tok

Turkish Journal of Zoology

In this survey, the tortoise and turtle fauna of Resadiye (Datça) Peninsula, which has not previously been studied in detail, is given. Mauremys caspica rivulata and Testudo graeca ibera specimens were collected as museum material or released after their measurements were taken, from four and nine localities respectively, establishing the status of the peninsula's testudine fauna. A total of 30 adult and eight juvenile specimens were studied morphologically. Observations on the ecological and biological characteristics of the testudines are also given.

Patella Species (Archaeogastropoda) Distributed In Saros Bay (Northest Aegean Sea), Bi̇lal Öztürk, Zeki̇ Ergen

Turkish Journal of Zoology

The present study has been carried out in order to determine the Patella species distributed in Saros Bay located on the northest of the Aegean Sea. For this purpose, 3 stations in the north and 3 stations in the south of the bay were chosen and a total of 340 specimens were collected from the 6 stations. In each station, 2 m2 of sampling area was considered. As a result of the taxonomic examinations based on the radula teeth, the Patella genera was represented by three species (Patella caerulea, Patella ulyssiponensis and Patella rustica) in Saros Bay. It was determined …

A Morphological Investigation On The Anuran Species Of The Reşadiye (Datça) Peninsula (Anura: Bufonidae, Hylidae, Ranidae), Cemal Varol Tok

Turkish Journal of Zoology

In this survey the amphibian fauna of Reşadiye (Datça) Peninsula, which has not been studied in detail so far, is given. No urodelan species has been encountered during the present work; but the presence of four different species belonging to three anuran families is established. Bufo bufo, Bufo viridis, Hyla arborea and Rana ridibunda specimens were collected from two, five, three and six different localities respectively, establishing the status of the peninsula's anura fauna. A total of 125 adult and two juvenile specimens were studied morphologically. Some observations on the ecological and biological characteristics of the anurans are also given.

A Spatial And Temporal Analysis Of Riparian Vegetation Along Satus Creek On The Yakama Indian Reservation, Kathryn Gellenbeck

All Master's Theses

Satus Creek provides critical habitat for the Yakima River Basin steelhead. A diverse community of riparian vegetation is important for healthy fish habitat; vegetation changes can affect shade, cover, channel structure, water quality, and food availability. The purpose of this thesis is to analyze and illustrate riparian vegetation change, both temporally and spatially, along three separate reaches of Satus Creek. A Geographic Information Systems approach was applied to assess the vegetation change by comparing plant species composition and density on 1949 and 1995 aerial photographs. The GIS approach allowed patterns and trends in the vegetation to be identified. In less …

An Investigation On The Morphology, Anatomy And Ecology Oforiganum Onites L.1, Ahmet Gönüz, Bilkan Özörgücü

Turkish Journal of Botany

Possible variations in the morphology, anatomy, ecology and phenology of Origanum onites L. ( Lamiaceae/Labitae) in rela-tion to altitudinal variations was studied together with the differences in etheric oil content. A decrease in the stem and lower leaf lengths was observed compared with an increase in the cortical area and vascular tissues in parallel with altitudinal increases. The number and size of stomata also varied with this factor. Etheric oil content was found to be different in relation to altitude.

On The Lizards Of The Reşadiye (Datça)Peninsula, Cemal Varol Tok

Turkish Journal of Zoology

Eleven species from six families of lizards have been found in the Reşadiye (Datça)Peninsula between the years 1990-1993.In this survey the morphological characteristics such as pholodisis,color-pattern and body measurements and ratios have been investigated.Systematic positions the species of which we have a sufficient number of samples were more accurate in terms of morfhological characteristics. Besides,the biological and ecological information on the species were also given.

Methods In Historical Ecology: A Case Study Of Tintic Valley, Utah, Jeffrey A. Creque, Neil E. West, James P. Dobrowolski

Wildland Resources Faculty Publications

Through use of repeat photography, archival research, and field observation to reconstruct landscape vegetation patterns and changes across a 120 year period in the upper Tintic Valley of central Utah, researchers found significant changes in landscape vegetation pattern over time, including change in pinyon-juniper woodland area. Previously reported massive woodland harvest associated with early mining, domestic and agricultural activities elsewhere in the Intermountain West also took place in Utah. The impact on woodland area of the agricultural "bull" fence alone was significant. More recent study area woodland expansion also occurred. Because intensive industrial activity associated with development of the Tintic …

Resource Allocation And Sucrose Mobilization In Light Limited Eelgrass Zostera Marina, Teresa Alcoverro, Richard C. Zimmerman, Donald G. Kohrs, Randall S. Alberte

OES Faculty Publications

This study evaluated the ability of Zostera marina L. (eelgrass) to balance the daily photosynthetic deficit by mobilization of carbon reserves stored in below-ground tissues during a period of extreme winter light limitation. A quantitative understanding of the mobilization process and its limitations is essential to the development of robust models predicting minimum light levels required to maintain healthy seagrass populations. Plants were grown in running seawater tanks under 2 light regimes. One treatment was provided with 2 h irradiance-saturated photosynthesis (H_sat) to produce severe Light Limitation, while control plants were grown under 7 h H_sat, …

Mesures Directes Et Modélisation De La Croissance Rapide D'Un Crinoïde Pédonculé Bathyal Au Large Des Bahamas (Direct Measurement And Inferred Model Of Rapid Growth In A Bathyal Stalked Crinoid From Bahamas Islands), Jérôme David, Charles G. Messing, Tomasz K. Baumiller, Nadia Améziane, Michel Roux

Marine & Environmental Sciences Faculty Articles

Several specimens of the isocrinid crinoid Neocrinus decorus were collected from a depth of 420 m off Bahamas Islands with the research submersible Johnson Sea Link. To study growth rates, these specimens were tagged, deployed and then recovered 250 days later. The average growth rate of stalk length is 10.8 cm.year⁻¹ with a maximum value at 14.3 cm.year⁻¹. These results allow us to propose a model of growth and regeneration for stalked crinoids in which the energy allocation is modulated through time to the arms and the stalk. Following arm autotomy, in order to re-establish optimum filtration …

A Study On Ecology And Biology Of Microtus Guentheridanford And Alston,1880 (Mammalia: Rodentia) In Turkey, Ercüment Çolak, Mustafa Sözen, Nuri Yi̇ği̇t, Şakir Özkurt

Turkish Journal of Zoology

In this study, ecology and biology of Microtus guentheriwere investigated based on both field and laboratory observations along with its effects on agricultural crops. It was determined that this vole has a shallow burrow with numerous entrances and does not store food in its burrow. In captivity, M. guentherigave litters from September to June and a female produced 42 pups, being seven litters during a reproduction season. The duration of pregnancy varied 20 to 21 days. The average litter size was 5.5 and young were born in an average weight of 3.3 g. The fur developed at an age of …

Effects Of Cutting Ashe Juniper Woodlands On Small Mammal Populations In The Texas Hill Country, K. A. Schnepf, J. A. Heselmeyer, David O. Ribble

Biology Faculty Research

We studied the effects of cutting Ashe juniper (Juniperus ashei Bucholz) woodlands on populations of small mammals at Friedrich Wilderness Park, north of San Antonio, Texas. Three patches of juniper ranging from 1.8 ha to 2.4 ha were cut to provide habitat for endangered black-capped vireos (Vireo atricapillus Woodhouse). We trapped small mammals along transects placed in the treated patches and in untreated areas of the park from October 1995 to May 1996 and again from October 1996 to March 1997. Three species of small mammals were trapped, but Peromyscus pectoralis Osgood (white-ankled mouse) was the …

Seasonal Patterns Of Nitrogen Fixation In Termites, A. D. Curtis, D. A. Waller

Biological Sciences Faculty Publications

Summary

1. Termite nitrogenase activity was highest in autumn and spring (≈ 3 µg N₂ fixed termite fresh mass (g)^–1 day^–1) and lowest in winter and summer (≈ 0·8 µg N₂ fixed termite fresh mass (g)^–1 day^–1).

2. The nitrogenase activity of worker termites was significantly higher than all other castes (1·58 ± 0·27 µg N₂ fixed termite fresh mass (g)^–1 day^–1).

3. Worker termites constituted the largest proportion of all the castes throughout the study period (≈ 90%).

4. The localized input of fixed nitrogen by termites …

Ec98-787 Glossary Of Ecosystem Terms, Thomas G. Franti, R. Herpel, G.R. Lingle

University of Nebraska-Lincoln Extension: Historical Materials

This extension circular contains ecosystem definitions from abiotic to wildlife refuge.

Physiological Energetics Of Buccinum Undatuml. (Gastropoda) Off Douglas,Isle Of Man (The Irish Sea), Ahmet E. Kideyş

Turkish Journal of Zoology

Physiological energetics of the common whelk ( Buccinum undatum) were studied in a population off Douglas, Isle of Man and an energy budget was constructed for the period February 1989 to January 1990. The components of the energy budget (in kJ m -2 year -1 ) for the population can be summarized thus: consumption (C)=753; growth production (P g )=34; reproductive production (P r )=4; mucus production=218; respiration (R)=96; ammonia excretion (U)=8; and faecal production (F)=393. Assimilation efficiency was 47.7%. P/B (annual production/biomass) was calculated as 1.40 representing an intermediate life span for this species.

Effect Of Artificial Flooding On The Vegetation And Avifauna Of Riparian Woodlands At Santa Ana National Wildlife Refuge, Hidalgo County, Texas, Charles David Castillo

Theses and Dissertations - UTB/UTPA

Riparian habitats along the Rio Grande at Santa Ana National Wildlife Refuge have dramatically decreased since the construction of Falcon Dam in 1953. Riparian habitats are dependent on annual or periodic flooding to maintain their biological integrity. Lack of seasonal flooding has contributed to changes in vegetative composition from riparian forests to thornscrub. Effects of artificial flooding on vegetation and avifauna of riparian woodlands were evaluated from 1995-1997 at the Santa Ana National Wildlife Refuge. Floodwaters caused the destruction of all existing herbaceous species along study transects and the regeneration of new and native seedlings. Avian abundance and diversity dramatically …

Modeling The Lower Chesapeake Bay Littoral Zone & Fringing Wetlands: Ecosystem Processes And Habitat Linkages Iii: Model Scenarios Related To Water Quality And Submersed Vegetation, Richard L. Wetzel, Christopher P. Buzzelli

Reports

No abstract provided.

Habitat Selection, Population Density, And Home Range Of The Elf Owl, Micrathene Whitneyl, At Santa Ana National Wildlife Refuge, Texas, Christopher Michael Gamel

Theses and Dissertations - UTB/UTPA

The Elf Owl, Micrathene whitneyi, is a regular summer resident of the southwestern United States. My objectives were to collect information concerning habitat selection, home range size, and population density of M. w. idonea, the subspecies occurring in the Lower Rio Grande Valley of Texas. Nocturnal surveys indicated greater use of chaparral habitat (92%) compared to riparian woodlands (8%). Utilized habitat was characterized by highest foliage density at 2.5-3.0 m, with a partial canopy at 3.8 $\pm$ 0.36 m and a semi-open understory. Home range size ranged from 0.24 to 2.6 ha, with a mean of 1.05 $\pm$ 0.33 ha. …

Alien Invaders: Envisioning Exotic Species In Florida, Kevin Archer

All Faculty Scholarship for the School of Graduate Studies and Research

No abstract provided.

Land Use Patterns In Relation To Lake Water Quality In The Messalonskee Lake Watershed, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College

Colby College Watershed Study: Other Area Studies

The main purpose of this study is to assess the current land use patterns and their influences on the water quality of Messalonskee Lake, including the biotic and abiotic parameters which are involved. More specifically, four main objectives were proposed. First, was to calculate the water budget and flushing rate for Messalonskee Lake. Second, was to determine the influence of current and historical land use patterns on lake water quality. Third, was to utilize gathered information to construct a phosphorus model, which will enable future water quality predictions to be made. Our fourth and final objective was to make recommendations …

The Red-Cockaded Woodpecker's Role In The Southern Pine Ecosystem, Population Trends And Relationships With Southern Pine Beetles, Richard N. Conner, D. Craig Rudolph, Daniel Saenz, Robert N. Coulson

Faculty Publications

This study reviews the overall ecological role of the Red-cockaded Woodpecker (Picoides borealis)in the southern pine ecosystem. It is the only North American woodpecker species to become well adapted to a landscape that was relatively devoid of the substrate typically used by woodpeckers for cavity excavation (i.e. snags and decayed, living hardwoods). Its adaptation to use living pines for cavity excavation has expanded the use of this fire-disclimax ecosystem for numerous other cavity-using species. As such, the Red-cockaded Woodpecker represents an important keystone species of fire-disclimax pine ecosystems of the South. Historically, populations of this woodpecker and other cavity dependent …

Function Of Funnel-Shaped Coral Growth In A High-Sedimentation Environment, Bernhard Riegl, Carlton Heine, George M. Branch

Marine & Environmental Sciences Faculty Articles

Advantages and disadvantages of a funnel-shaped growth in 2 coral species (Acropora clathrata, Turbinaria peltata) in a high-sedimentation environment (Natal, South Africa) were observed in the field and modeled in a flow tank. Funnel-shaped growth serves different purposes in different hydrographic settings. In calm waters with little currents (in our case deep reef areas, 18 to 25 m) funnel-shaped colonies served as 'sacrificial sediment traps': all sediment trapped inside the funnel was directed towards the centre, where it was concentrated. There, tissues underwent necroses, but all other tissues remained sediment free and healthy. In areas with high currents (in our …

Using The Spot-Mapping Censusing Technique To Assess Changes In Breeding Bird Communities At Santa Ana National Wildlife Refuge, Alamo, Texas, 1940-1996, Alberto Cantu

Theses and Dissertations - UTB/UTPA

Results of breeding-bird censuses done by Davis in 1940 and by Gehlbach between 1973-1978 at Santa Ana National Wildlife, Alamo Texas, were compared to a 1995-1996 bird survey done in Gehlbach's study area. According to the Wilcoxon rank-sum test, bird densities in 1940 and 1995-1996 were similar, while 1973-1978 densities were lower. The 1995-1996 bird community was 76% similar to both the earlier studies. However, the communities studied in 1940 and 1973-1978 had only a 60% similarity. Negligible differences in bird densities and species composition were found between the 1995 and 1996 communities. Differences are attributed to changes in vegetation …

A Comparison Of Secondary Successional Woody Vegetation In Two Revegetated Fields In South Texas And An Assessment Of Habitat Use By The Olive Sparrow, Arremonops Rufivirgatus, Patrick Grant Wright

Theses and Dissertations - UTB/UTPA

Aspects of plant species composition and structure of two revegetated fields in western Cameron County, Texas, were studied between 1992 and 1995. Avian habitat suitability was assessed using the Olive Sparrow, Arremonops rufivirgatus, as an indicator species. Total vegetation volume at the Longoria Wildlife Management Area (WMA), an area revegetated in 1961, was 0.745 $\rm m\sp3V/m\sp2$ and that of the Anacua WMA, revegetated in 1983-4, was 0.546 $\rm m\sp3V/m\sp2$ in 1992. Secondary woody species at the Longoria and Anacua WMA's had a Shannon's index of diversity of 0.619 and 0.264, respectively. Secondary woody vegetation at the Longoria WMA had a …