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2008

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Articles 151 - 180 of 213

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Possible Prehistoric Fishing Effects On Coastal Marine Food Webs In The Gulf Of Maine, Bruce J. Bourque, Beverly J. Johnson, Robert S. Steneck Jan 2008

Possible Prehistoric Fishing Effects On Coastal Marine Food Webs In The Gulf Of Maine, Bruce J. Bourque, Beverly J. Johnson, Robert S. Steneck

All Faculty Scholarship

No abstract provided.


Bird Numbers Decline In An Old Growth Forest: Long-Term Trends In Fernbank Forest, Christopher R. Showalter Jan 2008

Bird Numbers Decline In An Old Growth Forest: Long-Term Trends In Fernbank Forest, Christopher R. Showalter

Oriole

No abstract provided.


2008 Commencement Program, Seattle University Jan 2008

2008 Commencement Program, Seattle University

Commencement Programs

No abstract provided.


Effects Of Population Size And Density On Pollinator Visitation, Pollinator Behavior, And Pollen Tube Abundance In Lupinus Perennis, Christopher E. Bernhardt, Randall J. Mitchell, Helen J. Michaels Jan 2008

Effects Of Population Size And Density On Pollinator Visitation, Pollinator Behavior, And Pollen Tube Abundance In Lupinus Perennis, Christopher E. Bernhardt, Randall J. Mitchell, Helen J. Michaels

Biology Faculty Research

Both the number and the density of flowering plants in a population can be important determinants of pollinator abundance and behavior. We report the joint effects of population size and density on pollinator visitation and pollination success for Lupinus perennis (Fabaceae). Focusing on five pairs of populations, we matched one small population (125-800 flowering plants) with one distinctly larger population (1000-3000 flowering plants). In these pairs, population size did not affect pollinator communities or pollination success. All measures of pollination success increased significantly with density. Only bee behavior (number of flowers probed per inflorescence) exhibited a significant interaction of size …


Salt Marshes As A Source Of Chromophoric Dissolved Organic Matter (Cdom) To Southern California Coastal Waters, Catherine D. Clark, Liannea P. Litz, Stanley B. Grant Jan 2008

Salt Marshes As A Source Of Chromophoric Dissolved Organic Matter (Cdom) To Southern California Coastal Waters, Catherine D. Clark, Liannea P. Litz, Stanley B. Grant

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

To determine chromophoric dissolved organic matter (CDOM) sources in Southern California coastal waters, optical properties of a river outlet and adjacent tidally flushed salt marshes were monitored (dry season; June July 2001). Average absorption coefficients doubled at ebb vs. flood tides (4.8 +/- 1.5 vs. 2.1 +/- 0.9 m(-1); 300 nm), suggesting significant salt marsh CDOM inputs into coastal waters. Average spectral slopes were not statistically different for any sites or tides (0.010 +/- 0.002 nm(-1)), consistent with salt marsh CDOM dominating coastal waters. Three-dimensional fluorescence excitation-emission matrices (EEMs) at ebb tide showed contributions from terrestrial, protein, and marine humic-like …


Effects Of Agricultural Conservation Practices On Fish And Wildlife, Stuart R. Gagnon, Joseph R. Makuch, Cassandra Y. Harper Jan 2008

Effects Of Agricultural Conservation Practices On Fish And Wildlife, Stuart R. Gagnon, Joseph R. Makuch, Cassandra Y. Harper

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

This bibliography, in two volumes, is part of a multi-volume set developed by the Water Quality Information Center at the National Agricultural Library in support of the U.S. Department of Agriculture’s Conservation Effects Assessment Project (CEAP). The bibliography is a guide to recent scientific literature covering effects of agricultural conservation practices on fish and wildlife. The citations listed here provide information on how conservation programs and practices designed to improve fish and wildlife habitat, as well as those intended for other purposes, e.g., water quality improvement, affect various aquatic and terrestrial fauna.


Heterosis In Switchgrass: Biomass Yield In Swards, Kenneth P. Vogel, Rob B. Mitchell Jan 2008

Heterosis In Switchgrass: Biomass Yield In Swards, Kenneth P. Vogel, Rob B. Mitchell

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

Improving the biomass yield of switchgrass (Panicum virgatum L.) will improve its utility as a dedicated energy crop by increasing both its net and total energy yield per hectare. In a previous space-transplanted study, midparent heterosis for biomass yield was reported for population and specific F1 hybrids of the lowland-tetraploid cultivar Kanlow and the upland-tetraploid cultivar Summer. These two cultivars were proposed to be two different heterotic groups. The objective of this study was to determine the extent of heterosis for biomass yield in reciprocal Kanlow (K) and Summer (S) F1 population hybrids grown in simulated swards …


Swertia L. (Gentianaceae) In Nepal: Ethnobotany And Agenda For Sustainable Management, Kunjani Joshi Jan 2008

Swertia L. (Gentianaceae) In Nepal: Ethnobotany And Agenda For Sustainable Management, Kunjani Joshi

Ethnobotanical Leaflets

Swertia L. is a morphologically diverse but taxonomically distinct genus of the family Gentianaceae with ca150 species. In Nepal, Swertia L. comprises of 29 species with one endemic species (Swertia acaulis H. Sm.) which are widely distributed in the mountainous terrains of Eastern, Central and Western regions at altitude ranging from 600 to 5500m. (Joshi, 2007). The plants are economically important and comprise a major portion in the trade of medicinal plants. Recently more attention has been paid to the species of Swertia due to their usefulness to cure various ailments, their increasing price, and use of the plant …


Evidence For Low Levels Of Genetic Variation Among Zostera Marina Populations From The Atlantic West Coast, Eric Rosenzweig Jan 2008

Evidence For Low Levels Of Genetic Variation Among Zostera Marina Populations From The Atlantic West Coast, Eric Rosenzweig

Theses, Dissertations and Culminating Projects

Zoster a marina (eelgrass), can be found in the North Atlantic on the coast of Europe and the North Arctic, as well as the Pacific. On the Atlantic west coast this species grows as far south as North Carolina and into northern Canada. The cold waters of these regions support the habitat needed for the species. Eelgrass is vital to coastal communities. It serves as a food source for many organisms, hatching ground for fish species, absorbent of water pollutants, and soil stabilizer. Over the last 30 years, the once robust populations of Atlantic west coast eelgrass have withered into …


Some Fungi And Water Molds In Waters Of Lake Michigan With Emphasis On Those Associated With The Benthic Amphipod Diporeia Spp., Bozena Kiziewicz, Thomas F. Nalepa Jan 2008

Some Fungi And Water Molds In Waters Of Lake Michigan With Emphasis On Those Associated With The Benthic Amphipod Diporeia Spp., Bozena Kiziewicz, Thomas F. Nalepa

United States Department of Commerce: Staff Publications

To determine types of fungi in the water and associated with the benthic amphipod Diporeia spp., samples were collected at various depths in Lake Michigan in an area where the Diporeia population was in a severe state of decline. No fungi were found associated with living, freshly-dead, or dried Diporeia cultured separately from Lake Michigan water. When dead Diporeia and other organic substrates (snake skin and hemp seeds) were used to grow fungi in Lake Michigan water, a rich and diverse fungal and water mold community was revealed. A total of 31 species were found, with the most common genera …


A New Perspective: Atlantic Herring (Clupea Harengus) As A Case Study For Time Series Analysis And Historical Data, Emily Klein Jan 2008

A New Perspective: Atlantic Herring (Clupea Harengus) As A Case Study For Time Series Analysis And Historical Data, Emily Klein

Master's Theses and Capstones

This thesis endeavors to develop methods for the historical analysis of a specific species and location to begin understanding fishery patterns and change over time. The main goal was to develop statistical methods to address historical data and provide long-term information on fishery trends and potential relationships between the fishery and outside influences. The Atlantic herring (Clupea harengus) fishery was investigated for underlying patterns and the possible impact of outside variables and events from 1870 to 2007.

In the Gulf of Maine, Atlantic herring (Clupea harengus) provide critical forage for many economically valuable species, while supporting a major New England …


Population Ecology Of The Golden Mouse, Robert K. Rose Jan 2008

Population Ecology Of The Golden Mouse, Robert K. Rose

Biological Sciences Faculty Publications

An understanding of the population dynamics of a species requires knowledge of the major life-history parameters of a population, including age at maturity, distribution of age classes, and lifetime reproductive contribution of the sexes, sex ratio, length of the breeding season, mean litter size, rates of growth and survival, and life span. Because few long-term studies have been conducted with Ochrotomys nuttalli as the focal species of investigation, only fragmentary information is available for many population parameters. As importantly, densities of golden mice often are low, making them difficult to evaluate statistically. Little has been published on age at maturity …


Earthworm Abundances In Endophyte-Infected Tall Fescue Pastures In Northwest Arkansas, Ashley Rashe, Mary C. Savin Jan 2008

Earthworm Abundances In Endophyte-Infected Tall Fescue Pastures In Northwest Arkansas, Ashley Rashe, Mary C. Savin

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

The ecology of organisms that co-evolve within an ecosystem is likely to be distinct from that involving organisms recently introduced into an area. To better understand the relationship of earthworms with endophyte-infected tall fescue, earthworms in novel and toxic endophyte-infected tall fescue pastures were enumerated and identified as adults or juveniles. We hypothesized that differences in endophyte infection of the fescue would influence earthworm abundances. Earthworms in two toxic and two novel endophyte-infected tall fescue fields in Fayetteville, Ark., were sampled weekly from January through July 2007. Each type of endophyte-infected pasture was established in 1997 and 2003. Sampling was …


Low-Density Rodent Communities In Eastern Virginia, Robert K. Rose, Jean F. Stankavich Jan 2008

Low-Density Rodent Communities In Eastern Virginia, Robert K. Rose, Jean F. Stankavich

Virginia Journal of Science

Two communities of small mammals were live trapped every other week for 15 months in linear oilfield habitat bordered by forested swampland in eastern Virginia. All nine species of the rodent community were present, mostly in low numbers and often intermittently. All species were characterized by high transiency, with a minority of marked animals becoming resident. Despite high trappability, all but two species in these communities had extremely low densities, suggesting that most species could not sustain populations via in situ reproduction.


Alien Invaders! On-Site Programming (Grade 6), Discover Mojave: Forever Earth Jan 2008

Alien Invaders! On-Site Programming (Grade 6), Discover Mojave: Forever Earth

Curriculum materials (FE)

In the “Alien Invaders!” program, students investigate how quagga mussels might affect Lake Mead. Students collect water quality data such as clarity, pH, and temperature to determine current habitat conditions that have allowed quagga mussels to thrive in Lake Mead. Students learn about the consequences that quagga mussels could have on the lake and its living and non-living resources. Using the knowledge they’ve gained, students create their own management plans to prevent the spread of quagga mussels to other waterways.


Potential Site Productivity Influences The Rate Of Forest Structural Development, Andrew J. Larson, James A. Lutz, Rolf F. Gersonde, Jerry F. Franklin, Forest F. Hietpas Jan 2008

Potential Site Productivity Influences The Rate Of Forest Structural Development, Andrew J. Larson, James A. Lutz, Rolf F. Gersonde, Jerry F. Franklin, Forest F. Hietpas

Forest Management Faculty Publications

Development and maintenance of structurally complex forests in landscapes formerly managed for timber production is an increasingly common management objective. It has been postulated that the rate of forest structural development increases with site productivity. We tested this hypothesis for Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) forests using a network of permanent study plots established following complete timber harvest of the original old-growth forests. Forest structural development was assessed by comparing empirical measures of live tree structure to published values for Douglas-fir forests spanning a range of ages and structural conditions. The rate of forest structural development—resilience—exhibited a positive relationship …


A Literature Review Of The Effects Of Energy Development On Ungulates: Implications For Central And Eastern Montana, Mark Hebblewhite Jan 2008

A Literature Review Of The Effects Of Energy Development On Ungulates: Implications For Central And Eastern Montana, Mark Hebblewhite

Wildlife Biology Faculty Publications

A literature review of >160 scientific and technical reports was conducted to review the effects of energy development ungulates, separated by important seasonal and habitat types. Effects of energy development and human activity in general were assessed for elk, mule deer, pronghorn antelope, moose, bighorn sheep and woodland caribou. Weaknesses of the existing literature in addressing and providing guidelines for the management of energy development are presented. A recommended course of action for management oriented research is presented. Finally, a searchable electronic database is developed of the literature including abstracts and digital copies to aid in evaluating future energy development …


Phylogeny, Hybridization And The Evolution Of Fire-Stimulated Flowering Within The Grass-Leaved Goldenasters (Pityopsis, Asteraceae), View-Hune Teoh Jan 2008

Phylogeny, Hybridization And The Evolution Of Fire-Stimulated Flowering Within The Grass-Leaved Goldenasters (Pityopsis, Asteraceae), View-Hune Teoh

Electronic Theses and Dissertations

No abstract provided.


Using Stable Isotopes To Assess Population Structure And Feeding Ecology Of North Pacific Humpback Whales (Megaptera Novaeangliae), Briana Witteveen Jan 2008

Using Stable Isotopes To Assess Population Structure And Feeding Ecology Of North Pacific Humpback Whales (Megaptera Novaeangliae), Briana Witteveen

Electronic Theses and Dissertations

The North Pacific humpback whale (Megaptera novaeangliae) is a wide-ranging baleen whale species with a complex life history and population structure. As seasonal migrants, humpback whales are known to inhabit cooler, high-latitude waters when foraging and low-latitudes for mating and calving. Beyond this general migratory pattern, a number of demographic characteristics including, abundance, distribution, seasonal occurrence, and prey preferences remain unknown or poorly described. A complete understanding of humpback whale ecology is therefore lacking. Many methods used to explore these aspects of cetacean ecology are either prohibitively expensive or limited in the scope of what can be learned from their …


Early Performance Of Constructed Oyster Reefs In Great Bay, New Hampshire, Mark K. Capone Jan 2008

Early Performance Of Constructed Oyster Reefs In Great Bay, New Hampshire, Mark K. Capone

Master's Theses and Capstones

Several oyster reefs were constructed in Great Bay, New Hampshire using remotely-set oysters. A single large reef treatment and a cluster of several small reefs treatment were utilized to test hypotheses relevant to oyster restoration design, and to monitor early restoration reef performance. There was no significant difference in oyster size, density, and recruitment between two experimental reef structures, with both reef types having high survival and fast growth rates for the 2-year study. Both experimental reef structures had significantly higher recruitment rates than natural reefs in 2006, a year of relatively high recruitment (p < 0.05), and elevated yet not significantly higher recruitment rates in 2005, a weak recruitment year (p = 0.078). In situ fluorometry data showed that a restored reef can significantly impact chlorophyll-a levels in overlying water within two years of reef construction. Individual oyster clearance rates ranged from 1.87 L/hr--2.41L/hr.


Phenotypic Plasticity In Marine Intertidal Gastropods, Ahmed Mohammed Al-Mazrouai Jan 2008

Phenotypic Plasticity In Marine Intertidal Gastropods, Ahmed Mohammed Al-Mazrouai

School of Biological and Marine Sciences Theses

Phenotypic plasticity, the differential phenotypic expression of the same genotype in response to different environmental conditions, is a paradigm central of the study of evolution and ecology and is at the core of the "nature versus nurture" debate. Here, the marine gastropod Littorina littorea was used as a model to further our understanding of the potential role of phenotypic plasticity in intertidal systems. In the first study L. littorea was included in an investigation of induced defences across six species of intertidal marine gastropods in the families Littorinidae and Trochidae. Species differed in the magnitude and type of plastic response, …


Lung Cancer Mortality Is Elevated In Coal Mining Areas Of Appalachia, Michael Hendryx, Kathryn O'Donnell, Kimberly Horn Jan 2008

Lung Cancer Mortality Is Elevated In Coal Mining Areas Of Appalachia, Michael Hendryx, Kathryn O'Donnell, Kimberly Horn

Regional Research Institute Working Papers

Previous research has documented increased lung cancer incidence and mortality in Appalachia. The current study tests whether residence in coal mining areas of Appalachia is a contributing factor. We conducted a national county-level analysis to identify contributions of smoking rates, socioeconomic variables, coal mining intensity and other variables to age-adjusted lung cancer mortality. Results demonstrate that lung cancer mortality for the years 2000-2004 is higher in areas of heavy Appalachian coal mining after adjustments for smoking, poverty, education, age, sex, race and other covariates. Higher mortality may be the result of exposure to environmental contaminates associated with the coal mining …


"A New Species Of Freshwater Crab From Western Kenya" , Neil Cumberlidge, Michael Dobson Jan 2008

"A New Species Of Freshwater Crab From Western Kenya" , Neil Cumberlidge, Michael Dobson

Journal Articles

No abstract provided.


Assessment Of Four Years Of Marsh Restoration At The Jones Farm Experimental Restoration Facility In Northeast Ohio: Water Quality, Plant Community Development, And Adaptive Management, Jake J. Grossman Jan 2008

Assessment Of Four Years Of Marsh Restoration At The Jones Farm Experimental Restoration Facility In Northeast Ohio: Water Quality, Plant Community Development, And Adaptive Management, Jake J. Grossman

Honors Papers

In order to characterize water quality, plant community diversity, and invasive species management at a restored wetland, I have analyzed data collected from June 2004 to August 2007 at the George Jones Memorial Farm in New Russia Township, Ohio. The Jones wetlands site is comprised of six emergent, herbaceous marshes that were restored on an old-field site in 2003. The six cells were constructed using a uniform physical restoration treatment, managed uniformly for invasive species, and replanted using three planting treatments. Each planting treatment was applied to two wetlands; treatments included two designer plantings of native taxa and one self-designing …


Waterhole Dynamics And Chemical Signals Of African Elephants ( Loxodonta Africana ), Stacie Marie Castelda Jan 2008

Waterhole Dynamics And Chemical Signals Of African Elephants ( Loxodonta Africana ), Stacie Marie Castelda

College of Graduate Studies: Theses & Dissertations

The distribution of mammals in a savanna environment is influenced by abiotic and biotic factors. The African savanna experiences distinct wet and dry seasons. Species become spatially restricted around water resources during the dry season, resulting in increased intraspecies and interspecies resource-based aggregation. A dominate species, such as the African elephant (Loxodonta africana), may influence this aggregation. I examined the influence of wet and dry seasons and ambient temperature on the use of a waterhole by elephants as well as the co-occurrence of elephants and other mammals at the waterhole. Biodiversity scans (October 2004-June 2007) and were performed at a …


The Robert B. Gordon Natural Area For Environmental Studies, Erika Szonntag Jan 2008

The Robert B. Gordon Natural Area For Environmental Studies, Erika Szonntag

Gordon Natural Area History & Strategic Plan Documents

No abstract provided.


Individual-Based Artificial Ecosystems For Design And Optimization, Shivakar Vulli Jan 2008

Individual-Based Artificial Ecosystems For Design And Optimization, Shivakar Vulli

Masters Theses

"Individual-based modeling has gained popularity over the last decade, mainly due to the paradigm's proven ability to address a variety of problems seen in many disciplines, including modeling complex systems from bottom-up, providing relationship between component level and system level parameters, and discovering the emergence of system-level behaviors from simple component level interactions. Availability of computational power to run simulation models with thousands to millions of agents is another driving force in the widespread adoption of individual-based modeling. This thesis proposes an individual-based modeling approach for solving engineering design and optimization problems using artificial ecosystems"--Abstract, page iii.


A Photographic Survey Of Mammalian Trail Use In Big Basin Redwood State Park, Jennifer Robin Casey Jan 2008

A Photographic Survey Of Mammalian Trail Use In Big Basin Redwood State Park, Jennifer Robin Casey

Master's Theses

No abstract provided.


Pedogenesis Of Vesicular Horizons In Disturbed And Undisturbed Soils, Maureen L Yonovitz Jan 2008

Pedogenesis Of Vesicular Horizons In Disturbed And Undisturbed Soils, Maureen L Yonovitz

UNLV Retrospective Theses & Dissertations

Increasing desertification and anthropogenic soil disturbance is of growing concern to restoration ecologists in the Southwestern United States. This study examines how a common soil horizon of arid lands, the vesicular horizon, which is characterized by its discontinuous pores, responds to disturbance. The vesicular horizon is a near surface soil horizon typically composed of fine grained windblown material found beneath a desert pavement. Disturbance to the vesicular horizon may result in a change in pore morphology that will alter water movement through the horizon, affecting the ecology of the region. This research examines differences in pore morphology (area, perimeter, length …


Influence Of Pocket Gopher Mounds On Nonnative Plant Establishment In A Shrubsteppe Ecosystem, G. P. Kyle, Andrew Kulmatiski, Karen H. Beard Jan 2008

Influence Of Pocket Gopher Mounds On Nonnative Plant Establishment In A Shrubsteppe Ecosystem, G. P. Kyle, Andrew Kulmatiski, Karen H. Beard

Wildland Resources Faculty Publications

Soil disturbances across a wide range of spatial scales have been found to promote the establishment of invasive plant species. This study addresses whether mounds built by northern pocket gophers (Thomomys talpoides) in the shrubsteppe environment of north central Washington are facilitating plant invasions into native-dominated fields. Research was conducted in native-dominated plant communities adjacent to ex-arable, nonnative-dominated fields. To determine the effect of mounds on plant growth, we recorded new establishment and persistence of all plant species over 2 growing seasons on 10–19 mound and intermound areas in 10 fields. Nonnative plant establishment was not affected by mounds, but …