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Biology And Phylogeny Of The Cassidinae Gyllenhal Sensu Lato (Tortoise And Leaf-Mining Beetles) (Coleoptera: Chrysomelidae), Caroline S. Chaboo Jan 2007

Biology And Phylogeny Of The Cassidinae Gyllenhal Sensu Lato (Tortoise And Leaf-Mining Beetles) (Coleoptera: Chrysomelidae), Caroline S. Chaboo

Department of Entomology: Faculty Publications

A parsimony analysis was undertaken to test subfamily and tribal group concepts of Cassidinae (ca. 2000 genera, ca. 6000 species). An integrated account of their biology was synthesized from the primary literature. A detailed morphological study of adults, using Hemisphaerota palmarum Boheman as a model, formed the basis for evaluating characters previously utilized and for defining novel characters. The data matrix comprised 210 characters (from adults and immature stages, ecology and behavior), 6 outgroups, and 98 ingroup exemplar species (representing 94 genera and 39 of the 43 recognized cassidine tribes). Results support the monophyly of Cassidinae and place it as …


Individual Identification Of Polar Bears By Whisker Spot Patterns, Carlos Anderson Jan 2007

Individual Identification Of Polar Bears By Whisker Spot Patterns, Carlos Anderson

Electronic Theses and Dissertations

Many types of ecological studies require identification of individual animals. I developed and evaluated an automated identification system for polar bears (Ursus maritimus) based on their whisker spot patterns. First, I measured the reliability of using whisker spot patterns for identification from polar bear photographs taken in western Hudson Bay. This analysis involved estimating the complexity of each whisker spot pattern in terms of its information content. I found that 98% of patterns contained enough information to be reliable, and this result varied little among three different observers. Based on these results, I implemented a computer-aided identification system for polar …


Social Organization And Determinants Of Spatial Distribution Of Khur (Equus Hemionus Khur), Nita Shah, Qamar Qureshi Jan 2007

Social Organization And Determinants Of Spatial Distribution Of Khur (Equus Hemionus Khur), Nita Shah, Qamar Qureshi

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Khur (Equus hemionus khur) is an endangered species for the most part restricted in little Rann of Kutch (India) and surrounding areas. We investigated factors influencing spatial distribution and social organization of khur. The spatial distribution is largely influenced by distribution of food patches and water in this ecosystem. The inter group distances were smaller in resource rich areas in comparison to resource poor areas (p = 0.017). The group sizes are larger in areas having higher productivity (r = 0.85) and rainfall (r = 0.88). Four social units are observed in khur (a) Family …


Current Status Of The Khulan (Equus Hemionus) In The Trans-Altai Gobi, Enkhbileg Dulamtseren, Adiya Yadamjav, Dovchindorj Ganbold, Mijidorj Batmunkh Jan 2007

Current Status Of The Khulan (Equus Hemionus) In The Trans-Altai Gobi, Enkhbileg Dulamtseren, Adiya Yadamjav, Dovchindorj Ganbold, Mijidorj Batmunkh

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Since 1975, 25 wildlife surveys have been conducted in the Trans-Altai Gobi. In this paper we summarize results from the last 11 surveys, conducted between October 2000 and April 2005, and discuss our findings together with results from previous surveys.


Semi-Wild Population Of Kulans In The Bukhara Breeding Centre And Their Co-Habitation With Przewalski’S Horses, Karim Bahloul, Olga B. Pereladova, Natalia V. Soldatova, Ekaterina V. Sidorenko, Antoine J. Sempere Jan 2007

Semi-Wild Population Of Kulans In The Bukhara Breeding Centre And Their Co-Habitation With Przewalski’S Horses, Karim Bahloul, Olga B. Pereladova, Natalia V. Soldatova, Ekaterina V. Sidorenko, Antoine J. Sempere

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Asiatic wild asses and Przewalski's horses initially inhabited steppe, semi-desert and desert areas, but Przewalski's horses became extinct in the wild, and kulans are under threat of disappearance. The Bukhara Breeding Centre (Uzbekistan) was created in 1976 for conservation and reintroduction of wild ungulate species. In 1977-1978, five kulans (two males and three females) from Barsa-Kelmes Island on the Aral lake were introduced to the reserve. The group increased to 25-30 animals in 1995-1998, when five Przewalski's horses from Moscow and St. Petersburg zoos were introduced to the same territory. We analyzed the home ranges, preferred habitats and social interactions …


Distribution Of The Queen Snake (Regina Septemvittata) In Arkansas, Johnathan W. Stanley, Stanley E. Trauth Jan 2007

Distribution Of The Queen Snake (Regina Septemvittata) In Arkansas, Johnathan W. Stanley, Stanley E. Trauth

Journal of the Arkansas Academy of Science

We documented the distribution of the queen snake, Regina septemvittata, in northern Arkansas during the 2005 and 2006 activity seasons. Arkansas currently contains the only known disjunct population of this species west of the Mississippi River. Field work was conducted throughout the Boston Mountains of the Ozark Plateau to verify the presence of queen snakes from historic localities as well as to identify new localities containing these snakes. Seventeen individuals were found in the Mulberry River of Franklin and Johnson counties and the Illinois Bayou watershed of Pope County. Of these 17 snakes, 5 were kept as voucher specimens in …


Dietary Patterns And Breast Cancer Risk In The Shanghai Breast Cancer Study, Xiaohui Cui, Qi Dai, Marilyn Tseng, Xiao-Ou Shu, Yu-Tang Gao, Wei Zheng Jan 2007

Dietary Patterns And Breast Cancer Risk In The Shanghai Breast Cancer Study, Xiaohui Cui, Qi Dai, Marilyn Tseng, Xiao-Ou Shu, Yu-Tang Gao, Wei Zheng

Kinesiology and Public Health

The association of breast cancer with dietary patterns such as a western diet has not been studied in Asian women. We examined this among Shanghai Breast Cancer Study participants. Cases were of ages 25 to 64 years, diagnosed 08/1996-03/ 1998, and identified through a rapid case ascertainment system supplemented by the Shanghai Cancer Registry. Controls, selected from the general population of urban Shanghai, were frequency matched to cases by 5-year age group. Participants provided information on diet, lifestyle, and reproductive factors. In principal component analysis among 1,556 controls, two patterns emerged. a ‘‘vegetable-soy’’ pattern (tofu, cauliflower, beans, bean sprouts, green …


Biological Status Of Leatherside Chub: A Framework For Conservation Of Western Freshwater Fishes, Mark C. Belk, Jerald B. Johnson Jan 2007

Biological Status Of Leatherside Chub: A Framework For Conservation Of Western Freshwater Fishes, Mark C. Belk, Jerald B. Johnson

Faculty Publications

Outside of anadromous salmonids and a few endangered species, biology of native freshwater fishes of western North America is poorly known. What do we need to know to effectively manage native species and avoid decline and extinction? A recent analysis of the role of science in the Pacific salmon controversy outlines a clear framework for biological evaluation and management of native species. This framework has three components: (1) determine status of populations based on genetic and ecological variation, (2) identify and quantify threats to populations, and (3) determine actions to alleviate threats and promote conservation of populations. We use our …


Habitat Area Affects Arthropd Communities Directly And Indirectly Through Top Predators, Örjan Östman, Nicholas W. Griffin, Jared L. Strasburg, Jennifer A. Brisson, Alan R. Templeton, Tiffany M. Knight, Jonathan M. Chase Jan 2007

Habitat Area Affects Arthropd Communities Directly And Indirectly Through Top Predators, Örjan Östman, Nicholas W. Griffin, Jared L. Strasburg, Jennifer A. Brisson, Alan R. Templeton, Tiffany M. Knight, Jonathan M. Chase

School of Biological Sciences: Faculty Publications

Both habitat area and predators are known to affect the diversity and composition of species that live in a locality. In addition, habitat area can influence the presence of predators, indirectly affecting the diversity of prey. Thus, habitat area may influence species diversity directly and indirectly through the presence of top predators. Here we examine the effects of habitat area and predators on the species richness and composition of a foliage living arthropod community in a fragmented complex of glades (small grassland patches within a forested matrix) in the Ozark Plateau, Missouri. We find that a top predator, the eastern …


Lixus Cardui, A Biological Control Agent For Scotch Thistle (Onopordum Acanthium): Safe For Australia, But Not The Usa?, Joe Balciunas Jan 2007

Lixus Cardui, A Biological Control Agent For Scotch Thistle (Onopordum Acanthium): Safe For Australia, But Not The Usa?, Joe Balciunas

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Invasive exotic plants are often weeds in more than one country. After a biological control agent for a weed has been developed for use in one country, it is reasonable to consider using the same agent against the same weed in another country. ‘Transfer Projects’ can save considerable time and money, and they have been popular around the world. Lixus cardui Olivier (Coleoptera: Curculionidae), a weevil from Europe, was first used by Australian researchers to control Scotch thistle, Onopordum acanthium L. (Asteraceae). There are few close relatives of Scotch thistle in Australia, but that is not the case in North …


Stabel Isotope Turnover Rates And Diet-Tissue Discrimination In The Skin Of West Indian Manatees: Implcations For Evaluating Their Feeding Ecology And Habitat Use, Christy Alves Jan 2007

Stabel Isotope Turnover Rates And Diet-Tissue Discrimination In The Skin Of West Indian Manatees: Implcations For Evaluating Their Feeding Ecology And Habitat Use, Christy Alves

Electronic Theses and Dissertations

The West Indian manatee (Trichechus manatus) is an herbivorous marine mammal that occupies freshwater, estuarine, and marine habitats. Despite being considered endangered, relatively little is known about the feeding ecology of either of the two recognized subspecies, the Florida manatee (T.m. latirostris) and Caribbean or Antillean manatee (T.m. manatus). A better understanding of their respective feeding preferences and habitat use is essential to establish criteria on which conservation plans can be based. The present study expands on previous work on manatee feeding ecology by both assessing the application of stable isotope analysis to manatee tissue and providing critical baseline parameters …


Effects Of Isolation On Metapopulation Dynamics In Small-World Networks, Alaina Brooke Bernard Jan 2007

Effects Of Isolation On Metapopulation Dynamics In Small-World Networks, Alaina Brooke Bernard

Electronic Theses and Dissertations

Simulation models are valuable for making predictions that may be tested in natural systems and for understanding observed patterns. The simulation model developed for this thesis evaluates the effects of spatial network architecture, including organism dispersal patterns and isolation of habitats, on metapopulations. Two fields were merged throughout this project: metapopulation biology and small-world network theory. Small-world networks are characterized in their extremes as scale-free or single-scale. These models potentially simulate the networks of habitats and corridors in which metapopulations operate. Small-world network theory has been used to describe systems as diverse as rivers, the world-wide-web, and protein interactions, but …


Responses Of Small Rodents To Restoration And Management Techniques Of Florida Scrub At Cape Canaveral Air Force Station, Florid, Alexis Suazo Jan 2007

Responses Of Small Rodents To Restoration And Management Techniques Of Florida Scrub At Cape Canaveral Air Force Station, Florid, Alexis Suazo

Electronic Theses and Dissertations

Proper habitat management is essential for the survival and reproduction of species, especially those listed under state or federal laws as endangered, threatened or of special concern, and those with small local populations. Land managers use a combination of mechanical cutting and prescribed burning to manage and restore degraded scrub habitat in east central Florida. This approach improves habitat for the endangered Florida scrub-jay (Aphelocoma coerulescens), but little is known about its effects on other taxa, especially the threatened southeastern beach mouse (Peromyscus polionotus niveiventris). This single species approach may not be beneficial to other taxa, and mechanical cutting and …


Observations On The Diets Of An Anuran And Eight Lizard Taxa From Sonora, Chihuahua, And Coahuila, Mexico, With Some Notes On Clutch Sizes, Geoffrey R. Smith, J. A. Lemos-Espinal, Christopher B. Dibble, Megan E. Ogle, Joshua J. Schulte, Andrew J. Terlecky, Allison Boyd Jan 2007

Observations On The Diets Of An Anuran And Eight Lizard Taxa From Sonora, Chihuahua, And Coahuila, Mexico, With Some Notes On Clutch Sizes, Geoffrey R. Smith, J. A. Lemos-Espinal, Christopher B. Dibble, Megan E. Ogle, Joshua J. Schulte, Andrew J. Terlecky, Allison Boyd

Faculty Publications

No abstract provided.


Protecting Soil And Water In Forest Road Management, J. M. Grace Iii, B. D. Clinton Jan 2007

Protecting Soil And Water In Forest Road Management, J. M. Grace Iii, B. D. Clinton

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

The National Forest road system is the network that supports public recreation, which has become the primary use of the public lands. The pattern of use of National Forest roads for recreation has increased dramatically since the late 1940s and is expected to continue to increase beyond the rates observed today. However, research over the past 60 years clearly presents forest roads as a major source of sediment and soil erosion from forest watersheds. Threats to healthy forests have received increased attention in the past decade. In particular, roads, road management, and travel management will likely be critical to addressing …


Research Note: Hymenolepis Horrida (Cestoda: Hymenolepididae) And Catenotaenia Peromysci (Cestoda: Anoplocephalidae) In Voles From The Canadian Rockies, Yeen Ten Hwang, Scott Lyell Gardner, John S. Millar Jan 2007

Research Note: Hymenolepis Horrida (Cestoda: Hymenolepididae) And Catenotaenia Peromysci (Cestoda: Anoplocephalidae) In Voles From The Canadian Rockies, Yeen Ten Hwang, Scott Lyell Gardner, John S. Millar

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Cestodes from Clethrionomys gapperi (n=34) and Microtus longicaudus (n=8) from Kootenay National Park, British Columbia, Canada are reported. Two species of cestodes, Hymenolepis horrida (sensu lato) and Catenotaenia peromysci, were found in Clethrionomys gapperi, and one species of cestode, H. horrida, was found in Microtus longicaudus. Clethrionomys gapperi represents a new host record for C. peromysci. The Canadian Rockies is a new locality record for both cestode species.


Amazonian Exploitation Revisited: Ecological Asymmetry And The Policy Pendulum, Mark B. Bush, Miles R. Silman Jan 2007

Amazonian Exploitation Revisited: Ecological Asymmetry And The Policy Pendulum, Mark B. Bush, Miles R. Silman

Ocean Engineering and Marine Sciences Faculty Publications

The influence of pre-Columbian human populations on Amazonian ecosystems is being actively debated. The long-standing view that Amazonia was only minimally impacted by human actions has been challenged, and a new paradigm of Amazonia as a "manufactured landscape" is emerging. If such disturbance was the norm until just 500 years ago, Amazonian ecosystems could be far more ecologically resilient to disturbance than previously supposed. Alternatively, if the "manufactured landscape" label is an overstatement, then policy that assumes such resilience may cause substantial and long-lasting ecological damage. We present paleoecological data suggesting a middle path, in which some areas were heavily …


The Function Of Stilt Roots In The Growth Strategy Of Socratea Exorrhiza (Arecaceae) At Two Neotropical Sites, Gregory R. Goldsmith, Rakan A. Zahawi Jan 2007

The Function Of Stilt Roots In The Growth Strategy Of Socratea Exorrhiza (Arecaceae) At Two Neotropical Sites, Gregory R. Goldsmith, Rakan A. Zahawi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Arboreal palms have developed a variety of structural root modifications and systems to adapt to the harsh abiotic conditions of tropical rain forests. Stilt roots have been proposed to serve a number of functions including the facilitation of rapid vertical growth to the canopy and enhanced mechanical stability. To examine whether stilt roots provide these functions, we compared stilt root characteristics of the neotropical palm tree Socratea exorrhiza on sloped ( > 20°) and flat locations at two lowland neotropical sites. S. exorrhiza (n=80 trees) did not demonstrate differences in number of roots, vertical stilt root height, root cone circumference, root …


Pathways Of Anaerobic Carbon Cycling Across An Ombrotrophic–Minerotrophic Peatland Gradient, Jason K. Keller, Scott D. Bridgham Jan 2007

Pathways Of Anaerobic Carbon Cycling Across An Ombrotrophic–Minerotrophic Peatland Gradient, Jason K. Keller, Scott D. Bridgham

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Peatland soils represent globally significant stores of carbon, and understanding carbon cycling pathways in these ecosystems has important implications for global climate change. We measured aceticlastic and autotrophic methanogenesis, sulfate reduction, denitrification, and iron reduction in a bog, an intermediate fen, and a rich fen in the Upper Peninsula of Michigan for one growing season. In 3-d anaerobic incubations of slurried peat, denitrification and iron reduction were minor components of anaerobic carbon mineralization. Experiments using 14C-labeled methanogenic substrates showed that methanogenesis in these peatlands was primarily through the aceticlastic pathway, except early in the growing season in more ombrotrophic peatlands, …


Habitat And Distribution Of The Ruffed Lemur, "Varecia", North Of The Bay Of Antongil In Northeastern Madagascar, Evon R. Hekkala, Marius Rakotondratsima, Natalie Vasey Jan 2007

Habitat And Distribution Of The Ruffed Lemur, "Varecia", North Of The Bay Of Antongil In Northeastern Madagascar, Evon R. Hekkala, Marius Rakotondratsima, Natalie Vasey

Anthropology Faculty Publications and Presentations

Here we present information on the conservation status of ruffed lemurs (Varecia) north of the Bay of Antongil in northeastern Madagascar. Two contiguous protected areas were recently established that traverse this region via blocks of forest connected by narrow forest corridors: the Masoala National Park, which expands further to the east, and the Makira Protected Area, which expands further to the west and northwest. The two extant ruffed lemurs, Varecia variegata and V. rubra, overlapped in this region historically and, on rare occasions, hybridized. As such, land north of the Bay of Antongil is a critical part …


Oliver Ranch Science School Complex & Wild Horse And Burro Facility: Final Close-Out Report, Margaret N. Rees Dec 2006

Oliver Ranch Science School Complex & Wild Horse And Burro Facility: Final Close-Out Report, Margaret N. Rees

Oliver Ranch Project

“The mission of the Red Rock Desert Learning Center is to instill stewardship and respect by increasing knowledge and understanding of the Mojave Desert ecosystems and cultures through a unique experiential discovery program.”


Evaluating The Performance Of Leucaena Accessions For Agroforestry In Sub-Humid Environment, Southern Tanzania, A. E. Majule Dec 2006

Evaluating The Performance Of Leucaena Accessions For Agroforestry In Sub-Humid Environment, Southern Tanzania, A. E. Majule

Tanzania Journal of Science

The performance of Leucaena accessions on acid soils in eastern coast Tanzania for agroforestry was evaluated for three years. Plant tree parameters assessed were fodder yield and plant stem height, stem girth, the number of total branches and poles production. Also, Leucaena psyllid, a common pest threatening the plants was also counted. Soil parameters assessed were pH organic carbon, total nitrogen, exchangeable calcium and magnesium. Result showed significant difference in growth between Leucaena accessions. Leucaena leucocephal cv K8 and Leucaena diversifolia were able to grow fast reaching 4.7 and 3.3 m respectively within a period of three years. Leucaena diversifolia …


Spatial Variation In The Chemical Composition Of Natal Otholiths From A Reef Fish In The Galápagos Islands, Benjamin I. Ruttenberg, Robert R. Warner Dec 2006

Spatial Variation In The Chemical Composition Of Natal Otholiths From A Reef Fish In The Galápagos Islands, Benjamin I. Ruttenberg, Robert R. Warner

Biological Sciences

Over the past decade, researchers have used variation in the chemical composition of fish otoliths (earstones) to address a number of ecological questions, such as stock assessment and assessing rates of movement of individuals among habitats or life-history stages. However, these methods have yet to be applied successfully to the study of larval connectivity, a major unanswered question in marine ecology. Accomplishing this task requires a reference collection of pre-pelagic natal otoliths and accurate measurement of the chemical signatures of otoliths cores of recruits. We analyzed the chemical composition of natal otoliths from near-term benthic eggs of a damselfish (Stegastes …


Responses To Salinity Of Color Polymorphs In Two Populations Of The Sea Star, Pisaster Achraceus, Viren Johann Perumal Dec 2006

Responses To Salinity Of Color Polymorphs In Two Populations Of The Sea Star, Pisaster Achraceus, Viren Johann Perumal

Loma Linda University Electronic Theses, Dissertations & Projects

Pisaster ochraceus was analyzed to determine if varying salinities, animal color, or location affect the physiology of these sea stars. The three responses analyzed were aerobic respiration, ammonia excretion, and self-righting. The tested variables included two different color morphs (orange and purple) of P. ochraceus, two different locations (open coast and inland straits) in Washington State, and three salinities (22, 30, and 40 psu).

Wet mass-specific oxygen consumption rates were not significantly affected by color, location, or salinity, and Dry mass-specific oxygen consumption rates showed no significant differences for main effects, but a three-way interaction was identified. Similarly, ammonia …


Red Rock Desert Learning Center Stakeholder Phasing Meeting: October 5, 2006, Red Rock Desert Learning Center Oct 2006

Red Rock Desert Learning Center Stakeholder Phasing Meeting: October 5, 2006, Red Rock Desert Learning Center

Reports (RRLC)

  • Our goals for this meeting
  • What does phasing offer us?
  • Possible phasing scenados
  • Where do we go from here?
  • Other business regarding RRDLC


Evaluating The Long-Term Metacommunity Dynamics Of Tree Hole Mosquitoes, Alicia M. Ellis, L. Philip Lounibos, Marcel Holyoak Oct 2006

Evaluating The Long-Term Metacommunity Dynamics Of Tree Hole Mosquitoes, Alicia M. Ellis, L. Philip Lounibos, Marcel Holyoak

Dartmouth Scholarship

Four different conceptual models of metacommunities have been proposed, termed “patch dynamics,” “species sorting,” “mass effect,” and “neutral.” These models simplify thinking about metacommunities and improve our understanding of the role of spatial dynamics both in structuring communities and in determining local and regional diversity. We tested whether mosquito communities inhabiting water-filled tree holes in southeastern Florida, USA, displayed any of the characteristics and dynamics predicted by the four models. The densities of the five most common species in 3–8 tree holes were monitored every two weeks during 1978–2003. We tested relationships between habitat variables and species densities, spatial synchrony, …


Mother-Young Recognition In An Ungulate Hider Species: A Unidirectional Proce, Marco V.G. Torriani, Elisabetta Vannoni, Alan G. Mcelligott Sep 2006

Mother-Young Recognition In An Ungulate Hider Species: A Unidirectional Proce, Marco V.G. Torriani, Elisabetta Vannoni, Alan G. Mcelligott

Veterinary Science and Medicine Collection

Parent‐offspring recognition is usually crucial for survival of young. In mammals, olfaction often only permits identification at short range, and vocalizations are important at longer distances. Following and hiding antipredator strategies found in newborn mammals may also affect parental recognition mechanisms. We investigated mother‐offspring recognition in fallow deer, an ungulate hider species. We analyzed the structure of adult female and fawn contact calls to determine whether they are individually distinctive and tested for mother‐offspring recognition. Only females (and not fawns) have individualized vocalizations, with the fundamental frequency as the most distinctive parameter. Playback experiments showed that fawns can distinguish the …


Distribution, Morphology, And Genetic Affinities Of Dwarf Embedded Fucus Populations From The Northwest Atlantic Ocean, Arthur C. Mathieson, Clinton J. Dawes, Aaron L. Wallace, Anita S. Klein Sep 2006

Distribution, Morphology, And Genetic Affinities Of Dwarf Embedded Fucus Populations From The Northwest Atlantic Ocean, Arthur C. Mathieson, Clinton J. Dawes, Aaron L. Wallace, Anita S. Klein

New Hampshire Agricultural Experiment Station Publications

Dwarf embedded Fucus populations in the Northwest Atlantic Ocean are restricted to the upper intertidal zone in sandy salt marsh environments; they lack holdfasts and are from attached parental populations of F. spiralis or F. spiralis x F. vesiculosus hybrids after breakage and entanglement with halophytic marsh grasses. Dwarf forms are dichotomously branched, flat, and have a mean overall length and width of 20.3 and 1.3 mm, respectively. Thus, they are longer than Irish (mean 9.3 mm) and Alaskan (mean 15.0 mm) populations identified as F cottonii. Reciprocal transplants of different Fucus taxa in a Maine salt marsh confirm that …


Changes In Microbial Community Structure Of Petroleum Contaminated Sediments Are Reflected In Subsurface Geophysical Signatures, Jonathan P. Allen Aug 2006

Changes In Microbial Community Structure Of Petroleum Contaminated Sediments Are Reflected In Subsurface Geophysical Signatures, Jonathan P. Allen

Masters Theses

Petroleum contamination of sediments leads to dynamic changes in the subsurface. These include changes in the microbiota as well as in the subsurface geophysical and geochemical properties. Anomalously high conductivity values observed in subsurface zones contaminated with light non aqueous phase liquids (LNAPLs) have been suggested to be the result of microbial activity. Therefore, we investigated the interdependence between geoelectrical signatures and microbial community structure in petroleum contaminated field sediments and laboratory column experiments. Spatial and temporal changes in electrical conductivity of the subsurface paralleled changes in microbial community composition, with the highest conductivity values concomitant with specific anaerobic hydrocarbon-degrading …


Diversity And Abundance Of Small Mammals In The Serengeti Kopjes, Tanzania, C. D. Timbuka, J. D. Kabigumila Jul 2006

Diversity And Abundance Of Small Mammals In The Serengeti Kopjes, Tanzania, C. D. Timbuka, J. D. Kabigumila

Tanzania Journal of Science

Diversity and abundance of small mammals in the Serengeti kopjes were studied between November 2000 and February 2002. From 22,500 trap-nights and 3,300 bucket-nights, 4,903 small mammals in 18 species, 14 genera, 6 families and 3 orders were recorded. Muridae was the most dominant family with nine species. The highest number of species was recorded in the Maasai (14), Mbuzi Mawe (13) and Seronera (12) kopjes. The least number of species recorded in the Simba, Barafu and Wogakuria kopjes, with eight species each. Species diversity was highest in the Maasai kopjes (H'=2.337) and lowest in the Wogakuria kopjes (H'=1.794), with …