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Modeling The Influences Of Climate Change, Permafrost Dynamics, And Fire Disturbance On Carbon Dynamics Of High -Latitude Ecosystems, Qianlai Zhuang Apr 2001

Modeling The Influences Of Climate Change, Permafrost Dynamics, And Fire Disturbance On Carbon Dynamics Of High -Latitude Ecosystems, Qianlai Zhuang

Biological Sciences

A Soil Thermal Model (STM) with the capability to operate with a 0.5-day internal time step and to be driven with monthly input data was developed for applications with large-scale ecosystem models. The use of monthly climate inputs to drive the STM resulted in an error of less than 1�C in the upper organic soil layer and in an accurate simulation of seasonal active layer dynamics. Uncertainty analyses identified that soil temperature estimates of the upper organic layer were most sensitive to variability in parameters that described snow thermal conductivity, moss thickness, and moss thermal conductivity. The STM was coupled …


An Environmental Education Field Guide For Mystic Lake Wetland Habitats, Linda Jean Ellingston Jan 2001

An Environmental Education Field Guide For Mystic Lake Wetland Habitats, Linda Jean Ellingston

Theses Digitization Project

This curriculum guide is for grades four through six. It examines how wetlands, wildlife, and people interact and depend upon each other. The San Jacinto Valley wetland area is used as an example of wetland habitat destruction from population pressures that have changed the natural landscape. It is also used as an example of what habitat reconstruction can do to restore vital habitats. Through student contact with the wetlands increased awareness of the fragile interrelationships between the physical and biological components of a wetland habitat is gained. Students can use ecological themes to help them assimilate collected and given data …


Spatial Variability And Isotopic Studies Of The Prairie -Forest Transition Soil In Louisiana., Asfaw Bekele Jan 2001

Spatial Variability And Isotopic Studies Of The Prairie -Forest Transition Soil In Louisiana., Asfaw Bekele

LSU Historical Dissertations and Theses

The calcareous prairies of Louisiana are among the most endangered ecosystems in North America. The major threat to this ecosystem is the invasion by woody and herbaceous plants, primarily eastern red cedar (Juniperus virginiana ). The restoration and management of these rare plant communities require a thorough understanding of the soils supporting them. Geostatistical, fractal, and stable isotopic procedures were integrated to study the soil and vegetation spatial variability. The prairie soil was alkaline, the forest soil was acidic, and the transition soil was neutral. The spherical model described the spatial variability of virtually all the soil properties considered with …


A Critical Evaluation Of Research Techniques In Animal Ecology, Michelle A. Baker Jan 2001

A Critical Evaluation Of Research Techniques In Animal Ecology, Michelle A. Baker

Biology Faculty Publications

No abstract provided.


Scale, Ecological Fallacy, And The River Continuum Concept, Hope M. Childers Aug 2000

Scale, Ecological Fallacy, And The River Continuum Concept, Hope M. Childers

Graduate Theses, Dissertations, and Problem Reports (ETD)

Concern over scale is not new, and it is not restricted to geographers. Spatial and temporal scaling is a conceptual and methodological problem for all sciences using geographic information. This paper teases out issues of scale and ecological fallacy from the literature and discusses how these issues influence the applicability of an influential theoretical framework in stream ecology, the River Continuum Concept (RCC). Investigators are faced with decisions regarding scale during sampling location selection, field data capture, and subsequent data interpretation. A thorough understanding of the heterogeneity of stream habitats and the life histories of the organisms being studied could …


American Alligator Nesting Ecology In Impounded Marsh Habitat, Louisiana., Steven Richard Reagan Jan 2000

American Alligator Nesting Ecology In Impounded Marsh Habitat, Louisiana., Steven Richard Reagan

LSU Historical Dissertations and Theses

The goal was to monitor a large number of female alligators over a 3-year period to obtain information on alligator nesting ecology. This dissertation, although designed to estimate annual nesting rates, provides additional meaningful information on methods of capture, tag retention rates, nest spacing patterns, segregation of size classes, nest site fidelity, the relationship between attendance and nest success, the effects of fire ants on alligator nest success, the relationship between hatchling alligators and their mother, and hatchling dispersal. Passive integrated transponder (PIT), monel web, and cranial mounted reflector tags were evaluated for marking and identifying alligators. Use of harmonic …


Foraging Ecology And Conservation Biology Of African Elephants: Ecological And Evolutionary Perspectives On Elephant-Woody Plant Interactions In African Landscapes, Joseph Paine Dudley Apr 1999

Foraging Ecology And Conservation Biology Of African Elephants: Ecological And Evolutionary Perspectives On Elephant-Woody Plant Interactions In African Landscapes, Joseph Paine Dudley

Biological Sciences

The available scientific evidence indicates that African forest elephants and bush elephants are ecologically and evolutionarily distinct taxa. The current practice of regarding these two taxa as ecotypes of a single species, Loxodonta africana (i.e., L. a. africana Blumenbach 1797, L. a. cyclotis Matschie 1900) appears unwarranted, and obscures issues of major significance to the conservation biology of African elephants. Under a proposed taxonomic revision, the African bush elephant retains the designation Loxodonta africana Blumenbach 1797 while the African forest elephant is recognized as Loxodonta cyclotis Noack 1906. The browsing of woody plants by African bush elephants is a major …


Wolves And Bears: An Interdisciplinary Activity Guide For Grades 3-5, Susan L. Thomas Jan 1999

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 …


Behavioral And Physiological Responses Of The Lobster, Homarus Americanus, To Temperature: A New Synthesis, Steven Harold Jury Jan 1999

Behavioral And Physiological Responses Of The Lobster, Homarus Americanus, To Temperature: A New Synthesis, Steven Harold Jury

Doctoral Dissertations

Temperature has a pervasive influence on lobster behavior, physiology and ecology and affects their subsequent distribution in thermally variable habitats such as estuaries and coastal areas. A multidisciplinary approach, including field and laboratory studies, was used to show: (1) that lobsters sense temperature with warm and cool thresholds as small as 0.1--0.2°C; (2) the relationship between temperature and activity is not linear, but instead switches between a high activity level in warmer months (10--20°C) and a lower level in colder months (<10°C) with transition periods in the spring and fall; (3) Parallel studies in the lab and field show that daily levels of activity are not greatly influenced by small temperature variations (i.e. tidally induced changes of 14°C), but activity levels are significantly higher in the field (249 +/- 55.1 m/d) than in the laboratory (88 +/- 12.0 m/d); (4) lobsters prefer a narrow range of temperatures over others available in a thermal gradient and avoid temperatures >23.5 +/- 0.4°C, suggesting that they behaviorally thermoregulate. While this preferred temperature shifts seasonally, the final preferred temperature …


Methods In Historical Ecology: A Case Study Of Tintic Valley, Utah, Jeffrey A. Creque, Neil E. West, James P. Dobrowolski Jan 1999

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 …


Airbirds: Adaptative Strategies To The Aerial Lifestyle From A Life History Perspective., Manuel Marin-Aspillaga Jan 1998

Airbirds: Adaptative Strategies To The Aerial Lifestyle From A Life History Perspective., Manuel Marin-Aspillaga

LSU Historical Dissertations and Theses

"Airbirds" are defined as those birds that are adapted to almost constant life on the wing and do not perch, except for breeding and roosting. They use the air as the only medium in which to find and gather food. One taxon meets that definition: the swifts (Apodidae). Foraging zones of airbirds can be segregated in terms of clutch size, commuting foraging distance, nestling period, and nestling feeding rate. This study looked at foraging behavior and nestling diet, incubation patterns and mode of development in cypseloidine swifts, that as a group has extreme life history patterns. In a temperate one-egg …


Proximate And Ultimate Control Of Reproductive Effort In Northern Shovelers (Anas Clypeata) Nesting At Minto Flats, Alaska, Margaret Christine Maccluskie Apr 1997

Proximate And Ultimate Control Of Reproductive Effort In Northern Shovelers (Anas Clypeata) Nesting At Minto Flats, Alaska, Margaret Christine Maccluskie

Theses (Unassigned)

The purpose of this study was to examine factors that influence reproductive effort of female Northern Shovelers (Anas clypeata) nesting at Minto Flats, AK during summer 1991-1993. I investigated the importance of endogenous nutrient reserves to females during egg production and examined changes in organ weights and intestine lengths through the reproductive cycle. Changes in organ weights and intestine length were similar to those of shovelers nesting in Manitoba. Females used neither somatic lipid reserves, protein reserves, nor mineral reserves to produce eggs. Individual variation in somatic lipid reserves was explained by body size and nest initiation date, while variation …


A Search For Biologically Active Phytochemicals From Endemic Plants Of The Southeastern United States., Steven Lynn Robbs Jan 1997

A Search For Biologically Active Phytochemicals From Endemic Plants Of The Southeastern United States., Steven Lynn Robbs

LSU Historical Dissertations and Theses

In an investigation of allelopathy in the Florida scrub, bioassays with terpenes were performed against: Lactuca sativa, Rudbeckia hirta, Leptochloa dubia and Schizachyrium scoparium. Cineole was phytotoxic against Rudbeckia at 17 ppm and Lactuca at 165 ppm. (S)-camphor was phytotoxic to Rudbeckia at 1 ppm, Lactuca at 28 ppm, and Leptochloa and Schizachyrium at 134 ppm. (R)-Camphor, myrtenol and myrtenal were phytotoxic against Rudbeckia at concentrations of 28, 25 and 15 ppm respectively. Farnesol stimulated the germination of Schizachyrium at concentrations up to 50 ppm and at 100 ppm it reduced the radicle length of all test species. Geraniol stimulated …


Revitalizing Environmental Federalism, Daniel C. Esty Dec 1996

Revitalizing Environmental Federalism, Daniel C. Esty

Michigan Law Review

Politicians from Speaker Newt Gingrich to President Bill Clinton, cheered on by academics such as Richard Revesz, are eagerly seeking to return authority over environmental regulation to the states. In the European Union, localist opponents of environmental decisionmaking in Brussels rally under the banner of "subsidiarity." And in debates over international trade liberalization, demands abound for the protection of "national sovereignty" in environmental regulation. All of these efforts presume that a decentralized approach to environmental policy will yield better results than more centralized programs. This presumption is misguided. While the character of some environmental concerns warrants a preference for local …


Preserving Dynamic Systems: Wetlands, Ecology And Law, Alyson C. Flournoy Oct 1996

Preserving Dynamic Systems: Wetlands, Ecology And Law, Alyson C. Flournoy

UF Law Faculty Publications

Ecology has advanced human understanding of natural systems considerably over the course of this century. Wetlands law and policy have evolved in response to our increased understanding of wetlands and the many benefits we derive from them. Notwithstanding this shift in policy and law, roughly 50% of the wetlands that existed in the continental United States in colonial times have been lost or degraded largely as a result of recent human activity. Current policies struggle to reconcile the goal of preventing further loss with the pervasive concern for making our laws more efficient.

This essay explores the lessons ecology offers …


Summer Habitat Relationships And Foraging Ecology Of The Delta Bison Herd, Maria Berger May 1996

Summer Habitat Relationships And Foraging Ecology Of The Delta Bison Herd, Maria Berger

Biological Sciences

Investigations of habitat use, diet composition and diet selection of introduced plains bison (Bison bison bison) in interior Alaska in summer were conducted during 1989 through 1991. Bison used early- and mid-successional plant communities on the floodplain of the Delta River and wetlands above the floodplain. Grasses predominated in summer diets of bison, but substantial amounts of willow (Saiix) were included. Other shrubs were used much less than available, as were sedges. The role of sedges in bison diets may be changing as bison increasingly have exploited sedge-dominated wetland habitats. Experimental studies of the effects of bison grazing on forage …


Seasonal Diets Of Mink And Martens: Effects Of Spatial And Temporal Changes In Resource Abundance, Merav Ben-David Apr 1996

Seasonal Diets Of Mink And Martens: Effects Of Spatial And Temporal Changes In Resource Abundance, Merav Ben-David

Theses (Unassigned)

Seasonal changes in food availability and feeding habits of mink (Mustela vison) and martens (Martes americana) on Chichagof Island, Southeast Alaska, were studied through the analysis of natural abundance of stable isotopes. Dependence of the two species on marine-derived nutrients, carried to the terrestrial system via the upstream migration of spawning Pacific salmon (Onchorhynchus sp.), was investigated. Twenty-four mink and 75 martens were live-trapped repeatedly in early summer (prior to salmon runs), early autumn (post salmon runs), late winter, and in spring (during the mating season). A blood sample was obtained from each individual. In addition, 25 mink and 165 …


Movements, Distribution, And Population Dynamics Of Polar Bears In The Beaufort Sea, Steven C. Amstrup Apr 1995

Movements, Distribution, And Population Dynamics Of Polar Bears In The Beaufort Sea, Steven C. Amstrup

Theses (Unassigned)

I used mark and recapture, and radio telemetry to describe movements and population dynamics of polar bears of the Beaufort Sea. Rates of movement were lowest for females with cubs in spring, highest for females with yearlings in winter, and varied from 0.30-0.96 km/h. Total distances moved each month and year were 186-492 km and 1,454-6,203 km respectively. Highest and lowest levels of activity were in June and September. Activity levels were highest from mid-day to late evening. Females with cubs were more active than other bears. Annual home ranges varied from 12,730 km$\sp2$ to 596,800 km$\sp2$. The Beaufort Sea …


The Takin And Muskox: A Molecular And Ecological Evaluation Of Relationship, Pamela Groves Apr 1995

The Takin And Muskox: A Molecular And Ecological Evaluation Of Relationship, Pamela Groves

Theses (Unassigned)

This research clarifies the classification of and relationship between the takin (Budorcas taxicolor) and muskox (Ovibos moschatus). Although both are social ungulates of similar body size, takins live in dense mountainous habitats at temperate latitudes in Asia, and muskoxen live in open arctic habitats in Alaska, Canada and Greenland. Morphological, paleontological and chromosome comparisons have supported a close relationship between these species and their classification within the tribe Ovibovini in the subfamily Caprinae. Previous studies, however, have not defined the genetic relationship of the takin and muskox. This project used ecological and molecular comparisons to evaluate these proposed relationships. Ecological …


Ecology Of Birch Litter Decomposition And Forest Floor Processes In The Alaskan Taiga, Stephen Mitchell Wagener Apr 1995

Ecology Of Birch Litter Decomposition And Forest Floor Processes In The Alaskan Taiga, Stephen Mitchell Wagener

Theses (Unassigned)

Our view of an ecological process is influenced by the scale of our hypotheses and experiments. The forest floor can be examined as a system, where processes that affect ecosystem carbon and nutrient cycling are controlled by macroscale variables (seasonal climatic changes), which in turn affect microscale controls over microbial activity. In the forest floor of Alaskan taiga, annual layers of Equisetum (horsetail) litter demarcate cohorts of birch litter. We collected samples of the forest floor monthly during September 1992, and in June-September 1993. Forest floor material was separated into each of the three most recent litter cohorts, plus the …


Raptor Use Of The Idaho National Engineering Laboratory, Richard Wayne Hansen Jan 1994

Raptor Use Of The Idaho National Engineering Laboratory, Richard Wayne Hansen

Electronic Theses and Dissertations

Raptors are high trophic-level predators, and thus sensitive to environmental change. I conducted a basic ecological study of raptors using the Idaho National Environmental Laboratory (INEL), in southeastern Idaho, between 1991 and 1993 to assess effects of human activity on the site. Results were compared to previous raptor studies conducted on the INEL from 1974-1976 and in 1982, as well as with studies of rough-legged hawks, long-eared owls, and burrowing owls conducted during the late 1970’s and early 1980’s. Road-side raptor surveys were conducted from January through May in 1992 and 1993. Principle species recorded were rough-legged hawks, red-tailed hawks, …


Use And Misuse Of Mixed Model Analysis Of Variance In Ecological Studies, Cynthia C. Bennington, William V. Thayne Jan 1994

Use And Misuse Of Mixed Model Analysis Of Variance In Ecological Studies, Cynthia C. Bennington, William V. Thayne

Faculty & Staff Scholarship

Analysis of variance is one of the most commonly used statistical techniques among ecologists and evolutionary biologists. Because many ecological experiments involve random as well as fixed effects, the most appropriate analysis of variance model to use is often the mixed model. Consideration of effects in an analysis of variance as fixed or random is critical if correct tests are to be made and if correct inferences are to be drawn from these tests. A literature review was conducted to determine whether authors are generally aware of the differences between fixed and random effects and whether they are performing analyses …


Wolf-Caribou Relationships In A Multiple Ungulate Prey Ecosystem, Bruce Williams Dale Apr 1993

Wolf-Caribou Relationships In A Multiple Ungulate Prey Ecosystem, Bruce Williams Dale

Theses (Unassigned)

Winter wolf (Canis lupus) predation and functional response in wolf - caribou (Rangifer tarandus) dynamics were investigated in a multiple ungulate prey ecosystem in Gates of the Arctic National Park, Alaska. Prey selection, prey availability, prey switching, kill rates, and food availability for 4 wolf packs were estimated in March 1989, March 1990, and November 1990. Estimates for these study periods reflected near record, average, and early winter snow conditions, respectively. Wolves killed predominately caribou even if moose (Alces alces) or Dall sheep (Ovis dalli) were more abundant. Prey selection varied with study period; however, per wolf kill rates and …


The Significance Of Marine-Derived Biogenic Nitrogen In Anadromous Pacific Salmon Freshwater Food Webs, Thomas Clayton Kline Apr 1991

The Significance Of Marine-Derived Biogenic Nitrogen In Anadromous Pacific Salmon Freshwater Food Webs, Thomas Clayton Kline

Fisheries

The natural abundance of the stable isotope ratios $\sp{15}$N/$\sp{14}$N and $\sp{13}$C/$\sp{12}$C expressed as $\delta\sp{15}$N and $\delta\sp{13}$C was used to trace biogenic nutrients delivered by returning adult anadromous Pacific salmon into freshwater systems. These systems were Sashin Creek, a rapidly flushing stream located on Baranof Island, southeastern Alaska and Iliamna Lake, the major sockeye salmon, Oncorhynchus nerka, nursery lake in the Kvichak River watershed, Bristol Bay, southwestern Alaska. Marine-derived nitrogen (MDN) was quantifiable by use of an isotope mixing model based on comparison of biota $\delta\sp{15}$N in areas used for spawning by anadromous salmon with salmon-free controls within the same watershed. …


Ecological Studies Of Velvetbean Caterpillar, Anticarsia Gemmatalis Hubner, Pupae In Louisiana Soybean Fields., Joon-Ho Lee Jan 1989

Ecological Studies Of Velvetbean Caterpillar, Anticarsia Gemmatalis Hubner, Pupae In Louisiana Soybean Fields., Joon-Ho Lee

LSU Historical Dissertations and Theses

The microhabitat distribution of velvetbean caterpillar (VBC), Anticarsia gemmatalis Hubner (Lepidoptera: Noctuidae) was studied in soybean field cages and fields during 1985, 1986 and 1987. Larval density did not affect pupal horizontal distribution patterns related to direction and distance from the plant row. Pupae were found equally on both sides of soybean plant rows in a cage study. Pupae were found on and below the soil surface, but not on the plant. In 51 cm row spacing, both equal number and similar dispersion pattern of pupae were found on either side of the plant row. In 91 cm row spacing, …


The Legacy Of The Hawaiian Cultivator In Windward Valleys Of Hawaii. (Volumes I And Ii)., Ronald Norman Terry Jan 1988

The Legacy Of The Hawaiian Cultivator In Windward Valleys Of Hawaii. (Volumes I And Ii)., Ronald Norman Terry

LSU Historical Dissertations and Theses

The composition of a forest of relicts of cultivation in four uninhabited valleys in Kohala, Hawaii, is documented. A general hypothesis is made that arboreal distribution patterns are a function of both historical land use and ecological interaction since abandonment. The physical and historical geography of the valleys was investigated. Climate varies little, but distinct geomorphic zones offer differing biological environments. Prehistoric land use consisted of taro patches with intercropped banks. Talus slope gardens supported the Polynesian tree crops 'ohi'a 'ai (Eugenia malaccensis), kukui (Aleurites moluccana), 'ulu, (Artocarpus incisus), ti (Cordyline terminalis), and noni (Morinda citrifolia), important in today's flora. …


Newsletter, Florida Audubon Society - Florida Ornithological Society, Fall 1987, Florida Audubon Society, Florida Ornithological Society Oct 1987

Newsletter, Florida Audubon Society - Florida Ornithological Society, Fall 1987, Florida Audubon Society, Florida Ornithological Society

Florida Audubon Corkscrew Swamp Sanctuary - Records

Fall 1987 edition of the Florida Audubon Society-Florida Ornithological Society Newsletter, including sections on Christmas Bird Count, rare bird alerts, Endangered Species Act reauthorization, Ohio Key South preservation, notices, events, and Florida Ornithological Society news.


Correspondence, Organization Of Biological Field Stations, November 4-5, 1986, Henry R. Mushinsky, Clinton J. Dawes Nov 1986

Correspondence, Organization Of Biological Field Stations, November 4-5, 1986, Henry R. Mushinsky, Clinton J. Dawes

USF University Archives and Documents

Correspondence related to the inclusion of USF’s Ecological Research area in the Organization of Biological Field Stations due to its significance in areas such as fire ecology, research into sandhill plants and animals, wetland ecology studies, and wildlife conservation.


The Population Ecology And Nutrient Transport Of Gulf Menhaden In Fourleague Bay, Louisiana (Mortality, Growth, Feeding, Production, Migration)., Linda Ann Deegan Jan 1985

The Population Ecology And Nutrient Transport Of Gulf Menhaden In Fourleague Bay, Louisiana (Mortality, Growth, Feeding, Production, Migration)., Linda Ann Deegan

LSU Historical Dissertations and Theses

An ecological study of the young-of-the-year of three year-classes of gulf menhaden (Brevoortia patronus) was conducted from July 1981 to December 1983 in Fourleague Bay, Louisiana. This study documented gulf menhaden population ecology and the importance of gulf menhaden in the nutrient and energy balance of estuaries. Young-of-the-year gulf menhaden immigrated in winter and moved to tidal creeks and ponds, where they remained until midsummer. They then moved into open bays, where they remained until the fall. This migration pattern coincides with sequentially available, but spatially separate, productivity peaks in marsh and open bays. In the fall, they emigrated to …


Nutritional Ecology Of The Northern Pocket Gopher: A Study Of Nitrogen Balance, Miki M. Stuebe May 1984

Nutritional Ecology Of The Northern Pocket Gopher: A Study Of Nitrogen Balance, Miki M. Stuebe

Biology

The northern pocket gopher, Thomomys talpoides, is probably not able to maintain nitrogen (N) balance in winter in northern Utah if it eats only belowground plant material typical of that found in the caches it makes. Gophers burrowing 10 h/day would meet about 81% of their daily N requirement on such a diet, which has a true N digestibility of 49.0%, and a biological value of 90.6%. However, gophers could easily meet N requirements in winter by consuming material only slightly higher in N than cached material. High-N material (both plant and animal matter) is probably available to most …