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Resource-Based Habitat Associations In A Neotropical Liana Community, James W. Dalling, Stefan A. Schnitzer, Claire Baldeck, Kyle E. Harms, Robert John, Scott A. Mangan, Elena Lobo, Joseph B. Yavitt, Stephen P. Hubbell Sep 2012

Resource-Based Habitat Associations In A Neotropical Liana Community, James W. Dalling, Stefan A. Schnitzer, Claire Baldeck, Kyle E. Harms, Robert John, Scott A. Mangan, Elena Lobo, Joseph B. Yavitt, Stephen P. Hubbell

Faculty Publications

Summary: 1.Lianas are a conspicuous element of many tropical forests, accounting for up to 40% of woody stem density and 20% of species richness in seasonal forests. However, lianas have seldom been surveyed at sufficiently large spatial scales to allow an assessment of the importance of habitat variables in structuring liana communities. 2.We compare the association patterns of 82 liana species and an equivalent sample of tree species on the 50ha Forest Dynamics Project plot on Barro Colorado Island, Panama, with topographic habitat variables (high and low plateau, slope, swamp and streamside), and thirteen mapped soil chemical variables. In addition, …


Barbuda: A Caribbean Island In Transition, Andrew Sluyter, Amy E. Potter Jan 2012

Barbuda: A Caribbean Island In Transition, Andrew Sluyter, Amy E. Potter

Faculty Publications

No abstract provided.


The Phylogenetic Distribution And Ecological Role Of Carbon Monoxide Oxidation In The Genus Burkholderia, Carolyn F. Weber, Gary M. King Jan 2012

The Phylogenetic Distribution And Ecological Role Of Carbon Monoxide Oxidation In The Genus Burkholderia, Carolyn F. Weber, Gary M. King

Faculty Publications

Burkholderia is a physiologically and ecologically diverse genus that occurs commonly in assemblages of soil and rhizosphere bacteria. Although Burkholderia is known for its heterotrophic versatility, we demonstrate that 14 distinct environmental isolates oxidized carbon monoxide (CO) and possessed the gene encoding the catalytic subunit of form I CO dehydrogenase (coxL). DNA from a Burkholderia isolate obtained from a passalid beetle also contained coxL as do the genomic sequences of species H160 and Ch1-1. Isolates were able to consume CO at concentrations ranging from 100 ppm (vol/vol) to sub-ambient (< 60 ppb (vol/vol)). High concentrations of pyruvate inhibited CO uptake (> 2.5 mM), but mixotrophic consumption of CO and pyruvate occurred …


Function And Diversity Of The Ship, Trinity, And Tiger Shoal Complex, With Emphasis On Macrofauna And Spawning Blue Crabs (Callinectes Sapidus), Carey George Gelpi Jr. Jan 2012

Function And Diversity Of The Ship, Trinity, And Tiger Shoal Complex, With Emphasis On Macrofauna And Spawning Blue Crabs (Callinectes Sapidus), Carey George Gelpi Jr.

LSU Doctoral Dissertations

The ecological and economic value of sandy shoals off the Louisiana coast is not well understood. During three years of comprehensive benthic sampling and environmental measurements I studied the Ship, Trinity, Tiger Shoal Complex (STTSC), which comprises changing and discrete benthic habitats including high relief sandy shoals, and muddier, mostly deeper off-shoal areas, prone to hypoxia. Benthic macrofaunal assemblages of shoals included endemic species, and shoal communities were significantly different from each other and the muddier offshoal habitat, contributing to northern Gulf of Mexico (GoM) regional biodiversity. Sand percentage was the most influential environmental parameter shaping macrofaunal community composition across …


The Distribution And Diversity Of Functional Gene Pathways Controlling Sulfur Speciation In Lower Kane Cave, Wyoming, Audrey Tarlton Paterson Jan 2012

The Distribution And Diversity Of Functional Gene Pathways Controlling Sulfur Speciation In Lower Kane Cave, Wyoming, Audrey Tarlton Paterson

LSU Master's Theses

Defining the linkages between microbial metabolic activity and environmental geochemistry can be used to understand how carbonate dissolution in sulfidic karst systems proceeds. In Lower Kane Cave, Wyoming, sulfidic springs support taxonomically distinct microbial communities that are also associated with putative sulfur metabolisms (e.g., oxidation of reduced sulfur compounds, sulfate reduction, and sulfur disproportionation) that influence carbonate dissolution. The distribution of diverse microbial groups in other terrestrial subsurface environments is not well understood, making Lower Kane Cave ideal for study. Molecular genetics techniques were used to uncover diversity of 16S rRNA genes and bacterial soxB and aprA functional genes. Aqueous …


Biomass And Mass Balance Isotope Content Of Mussel Seep Populations, Philip Martin Riekenberg Jan 2012

Biomass And Mass Balance Isotope Content Of Mussel Seep Populations, Philip Martin Riekenberg

LSU Master's Theses

Cold seep mussels, Bathymodiolus childressi, are common cold seep constituents that form large populations at upper continental slope (500-1000 m) cold seep sites in the Northern Gulf of Mexico. These mussels utilize methane present through symbiotic relationships with methanotrophic bacteria. This study uses a coupled isotope technique to determine the relative incorporation of respiratory carbon in the shell as a measure of the availability of methane between different seep sites. This method indicates a higher abundance of methane at the Brine Pool site than at the Bush Hill site which appears significantly more resource limited and that changes in methane …


Oil-Mediated Mortality And Induced Behavioral Modifications Of Coastal Insects, Benjamin Jacob Adams Jan 2012

Oil-Mediated Mortality And Induced Behavioral Modifications Of Coastal Insects, Benjamin Jacob Adams

LSU Master's Theses

The Deepwater Horizon oil spill affected over one thousand kilometers of the southeastern United States’ coast in the Gulf of Mexico especially Louisiana’s salt marshes. These marshes are a vital part of the state’s economy and coastal ecology; however, the insects residing in this area remain largely unstudied. The goal of my project was to answer specific questions arising from two ongoing investigations of the insects in the oiled marshes. I sampled insects using sweep nets and insect vacuums to determine the most efficient technique to use in the marsh, compared insects collected in oiled and non-oiled marshes, and completed …