Digital Commons Network^™

A 2000-Year History Of Forest Disturbance In Southern Pacific Costa Rica: Pollen, Spore, And Charcoal Evidence From Laguna Santa Elena, Kevin John Anchukaitis

Masters Theses

Paleoecological records reveal information about past changes in vegetation composition and disturbance in tropical ecosystems. These environmental histories have direct bearing on modem ecological studies and the management of protected areas, and provide information about the interaction between prehistoric peoples and their environment. In this study, I reconstruct prehistoric and historic forest disturbance and vegetation change from southern Pacific Costa Rica, in the vicinity of the Las Cruces Biological Station and the La Amistad International Park and Biosphere Reserve. Pollen and charcoal in sediments from Laguna Santa Elena reveal a nearly continuous record of human alteration of these tropical forests …

Tcwp Newsletter No. 246, Tennessee Citizens For Wilderness Planning

Tennessee Citizens for Wilderness Planning Newsletters

No abstract provided.

Exergy And Information Indices: A Comparison For Use In Structurally Dynamic Models, Brian D. Fath

International Congress on Environmental Modelling and Software

Ecosystems are open, dynamic systems changing both their structure and their function over time. A model, which is an abstraction of the system manifest at the time of its construction, can project future dynamics so long as the fundamental structure of the system does not change. A primary modelling challenge arises when the system structure changes, i.e., internal reorganization, as a result of external perturbation. Ideally, one could include algorithms in the model to anticipate such changes, but that would entail knowing a great deal more about the system and disturbances to it than is possible. Other methods to anticipate, …

Indirect Effect Of Habitat Destruction On Ecosystems, Nariyuki Nakagiri, K. Tainaka

International Congress on Environmental Modelling and Software

Habitat destruction is one of the primary causes of species extinction in recent history. Even if the destruction is restricted to a local and small area, its accumulation increases the risk of extinction. To study local destruction of habitat, we present a lattice ecosystem composed of prey (X) and predator (Y). This system corresponds to a lattice version of the Lotka-Volterra model, where interaction is allowed between neighboring lattice points. The lattice is partly destroyed, and destructed sites or barriers are randomly located between adjacent lattice points with the probability p. The barrier interrupts the reproduction of X, but the …

Parallel Characterization Of Anaerobic Toluene-And Ethylbenzene-Degrading Microbial Consortia By Pcr-Denaturing Gradient Gel Electrophoresis, Rna-Dna Membrane Hybridization, And Dna Microarray Technology, Yoshikazu Koizumi, John J. Kelly, Tatsunori Nakagawa, Hidetoshi Urakawa, Said El Fantroussi, Saleh Al-Muzaini, Manubu Fukui, Yoshikuni Urushigawa, David A. Stahl

Biology: Faculty Publications and Other Works

A mesophilic toluene-degrading consortium (TDC) and an ethylbenzene-degrading consortium (EDC) were established under sulfate-reducing conditions. These consortia were first characterized by denaturing gradient gel electrophoresis (DGGE) fingerprinting of PCR-amplified 16S rRNA gene fragments, followed by sequencing. The sequences of the major bands (T-1 and E-2) belonging to TDC and EDC, respectively, were affiliated with the family Desulfobacteriaceae. Another major band from EDC (E-1) was related to an uncultured non-sulfate-reducing soil bacterium. Oligonucleotide probes specific for the 16S rRNAs of target organisms corresponding to T-1, E-1, and E-2 were designed, and hybridization conditions were optimized for two analytical formats, membrane and …

Fine Root Vitality And Its Application In A Minirhizotron Study Of A Co2 Enrichment In A Florida Scrub Oak Ecosystem, Brandon Todd Herbert

Biological Sciences Theses & Dissertations

Minirhizotron images are assigned color codes to approximate the age of individual roots in situ. Triphenyl-tetrazolium chloride (TTC) has been used to measure the vitality of plant tissue by detecting dehydrogenase activity. TTC was used to assess the vitality of root tissue by color in a scrub oak ecosystem at Kennedy Space Center in central Florida. Roots were excavated, sorted into four color classes and stained with TTC. The product of the reduction of TTC by dehydrogenase enzyme, formazan, was extracted and its absorbance recorded using a spectrophotometer. A significant difference (p2 enrichment being conducted on a scrub oak …

Cooperative Upland Wildlife Research And Surveys, Alan Woolf, Wayne E. Thogmartin, Whitney Weber

Final Reports

No abstract provided.

The Future Of Stock Enhancements: Lessons For Hatchery Practice From Conservation Biology, Culum Brown, Rachel L. Day

Aquaculture Collection

The world’s fish species are under threat from habitat degradation and over-exploitation. In many instances, attempts to bolster stocks have been made by rearing fish in hatcheries and releasing them into the wild. Fisheries restocking programmes have primarily headed these attempts. However, a substantial number of endangered species recovery programmes also rely on the release of hatchery-reared individuals to ensure long-term population viability. Fisheries scientists have known about the behavioural deficits displayed by hatchery-reared fish and the resultant poor survival rates in the wild for over a century. Whilst there remain considerable gaps in our knowledge about the exact causes …

Biological Synopsis Of The Black Bream, Acanthopagrus Butcheri (Munro) (Teleostei: Sparidae) In Western Australia With Reference To Information From Other Southern States, Jeffrey V. Norriss, J E. Tregonning, Rod C J Lenanton, Gavin A. Sarre

Fisheries research reports

This synopsis presents a review of the literature and research to April 2001on the biology of black bream, Acanthopagrus butcheri (Sparidae), particularly in relation to Western Australian populations. A. butcheri is a commercially and recreationally important species, and is endemic to the coastal lakes, estuaries, river systems and sheltered coastal waters of southern Australia, including Tasmania. Separate stocks reside within each river/estuarine system in southwestern Australia, and there is considerable variation in feeding, growth rates and age at maturity among stocks. For rivers/estuaries that are seasonally flushed in winter, downstream movement with the flush is followed by the annual upstream …

Spectator 2002-05-16, Editors Of The Spectator

The Spectator

No abstract provided.

A Field And Enclosure Study Of Population Dynamics And The Effects Of Density On Fecundity Of Anolis Carolinensis And Anolis Sagrei (Sauria: Polychrotidae) In Conspecific And Heterospecific Groups, Todd C. Vincent

Doctoral Dissertations

Populations of the lizard species Anolis carolinensis in Florida have declined with the spread of the invading Anolis sagrei. This phenomenon appears to be accentuated by habitat disturbance. I conducted an observational field study to investigate the population dynamics of the two species in undisturbed areas of Florida. The main objective of the study was to measure seasonal dynamics in the relative densities of juveniles and adults in allopatric and sympatric populations of the two species in these vegetationally complex habitats. The results of this study led me to design and conduct an outdoor enclosure experiment to investigate the possible …

Masting By Eighteen New Zealand Plant Species: The Role Of Temperature As A Synchronizing Cue, Eric M. Schauber, Dave Kelly, Peter Turchin, Chris Simon, William G. Lee, Robert B. Allen, Ian J. Payton, Peter R. Wilson, Phil E. Cowan, R E. Brockie

Publications

Masting, the intermittent production of large flower or seed crops by a population of perennial plants, can enhance the reproductive success of participating plants and drive fluctuations in seed-consumer populations and other ecosystem components over large geographic areas. The spatial and taxonomic extent over which masting is synchronized can determine its success in enhancing individual plant fitness as well as its ecosystem-level effects, and it can indicate the types of proximal cues that enable reproductive synchrony. Here, we demonstrate high intra- and intergeneric synchrony in mast seeding by 17 species of New Zealand plants from four families across >150000 km …

Insights, Spring, 2002, Utah State University

Discovery Magazine

Bi-annual alumni newsletter for the College of Science of Utah State University in Logan.

Coyote Foraging Ecology, Vigilance, And Behavioral Cascades In Response To Gray Wolf Reintroduction In Yellowstone National Park, T. Adam Switalski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Vigilance behavior can aid in the detection of predators and may also play a role in observation of conspecifics, in food acquisition, and in the prevention of kleptoparasitism. However, in most occasions, vigilance is most important as an antipredator function. Generally, factors that increase the risk of predation also increase the amount of vigilance. We examined whether the reintroduction of the large predator, the wolf, in Yellowstone National Park (YNP) would influence coyote vigilance and foraging ecology. From December 1997 to July 2000, we collected 1743 h of coyote activity budgets. Coyote home ranges occurred within wolf territories (termed high-use …

Statmod: A Tool For Interfacing Arcview® Gis With Statistical Software To Facilitate Predictive Ecological Modeling, Christine M. Garrard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As geographical information systems and spatial data become more accessible, predictive spatial modeling in ecology is becoming more common. Unfortunately, not all ecologists possess the necessary skills to successfully combine statistical models and geographical information systems. In response to this problem, I wrote an extension for ArcView^® GIS called StatMod. This extension interfaces ArcView GIS with SAS^® and S-PLUS^® statistical software and walks the user through creating and mapping logistic regression and classification and regression tree models.

StatMod was then used to run a series of analyses that would have been difficult without such a tool. A …

The Ecology Of Lianas And Their Role In Forests, Stefan A. Schnitzer, Frans Bongers

Biological Sciences Faculty Research and Publications

Recent studies have demonstrated the increasingly important role of lianas (woody vines) in forest regeneration, species diversity and ecosystem-level processes, particularly in the tropics. Mechanisms responsible for the maintenance of liana species diversity could yield new insights into the maintenance of overall species diversity. Lianas contribute to forest regeneration and competition, not only by competing directly with trees, but also by differentially affecting tree species and thus changing how trees compete among themselves. In addition, they contribute considerably to ecosystem-level processes, such as whole-forest transpiration and carbon sequestration. As the rate of tropical forest disturbance increases, they are likely to …