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Full-Text Articles in Life Sciences

Are Biodiverse Communities More Resistant To Invasion? A Case Study With Marine Fouling Communities, Taylor Robert Bruntil Jan 2023

Are Biodiverse Communities More Resistant To Invasion? A Case Study With Marine Fouling Communities, Taylor Robert Bruntil

Cal Poly Humboldt theses and projects

The theory of biotic resistance predicts that more diverse communities should be less susceptible to invasion by novel species, but given the opposing results of multiple observational and experimental studies in marine systems, it is unclear how changes in environmental conditions can affect invasion success in communities that differ in diversity. I used marine fouling communities to test how the diversity of the species present in an initial community (hereafter termed “resident species”) affected the establishment and growth of all species not present in the initial communities (hereafter termed “novel species”) at two locations at the Eureka Public Marina, in …


Macrolichen Inventory Of The Horse Mountain Botanical Area, Six Rivers National Forest, California, Usa, Sarah Norvell Conway Jan 2023

Macrolichen Inventory Of The Horse Mountain Botanical Area, Six Rivers National Forest, California, Usa, Sarah Norvell Conway

Cal Poly Humboldt theses and projects

Macrolichen diversity and community composition was determined for an area of high botanical interest in the Coast Ranges of Northern California – the Horse Mountain Botanical Area (HMBA) in Six Rivers National Forest. The Coast Ranges have been suggested to have high epiphytic macrolichen diversity, yet detailed site-specific macrolichen surveys are lacking for the area. Here we present comprehensive data on macrolichens of the HMBA integrated with environmental metadata at the landscape level. Twenty 0.4 ha sampling plots were positioned across the varying habitats of the HMBA and macrolichens were intensively sampled from all substrata. Out of 888 total collections, …


Environmental Effects On Constructed Wetland Microbial Diversity And Function In The Context Of Wastewater Management, Sandrine Grandmont-Lemire Jan 2022

Environmental Effects On Constructed Wetland Microbial Diversity And Function In The Context Of Wastewater Management, Sandrine Grandmont-Lemire

Cal Poly Humboldt theses and projects

Microbial communities play a crucial role in ecosystems, yet we know little about how microbial diversity influences ecosystem functioning. An important gap in our understanding is how environmental change affects microbial Biodiversity-Ecosystem Function relationships (BEF). These complex interactions between microbial biodiversity and ecosystem function can influence major biogeochemical processes, such as the nitrogen cycle in wetland ecosystems, which play an important role in managing wastewater. To address the effect of biodiversity on function, my study investigates the BEF relationships between microbial diversity and the function in terms of ammonia removal from wastewater at the Arcata Wastewater Treatment Facility (AWTF) both …


Conifer Encroachment And Removal In A Northern California Oak Woodland: Influences On Ecosystem Physiology And Biodiversity, Gabriel S. Goff Jan 2021

Conifer Encroachment And Removal In A Northern California Oak Woodland: Influences On Ecosystem Physiology And Biodiversity, Gabriel S. Goff

Cal Poly Humboldt theses and projects

Oregon white oak (Quercus garryana) woodlands across their range are becoming increasingly threatened by encroaching Douglas-fir encroachment (Pseudotsuga menziesii) as a result of fire exclusion. Using water potential (Ψ), stomatal conductance (gs), xylem water stable isotopes (dD), and three metrics of biodiversity, this study investigates the effects of conifer encroachment and removal at the ecosystem-scale. The study was set in an Oregon white oak woodland in northern California and compared three levels of encroachment before and after conifer removal. Findings indicate that heavily encroached stands have the least amount of water stress and gas …


Efficacy Of Forest Restoration Treatments Across A 40-Year Chronosequence At Redwood National Park, Kevin Soland Jan 2020

Efficacy Of Forest Restoration Treatments Across A 40-Year Chronosequence At Redwood National Park, Kevin Soland

Cal Poly Humboldt theses and projects

Following 20th century logging, much of the natural coast redwood (Sequoia sempervirens) range consists of dense second-growth stands with slow tree growth and low biodiversity. There is a landscape-scale effort in much of coastal northern California to increase tree growth rates and ecosystem biodiversity via thinning treatments, thereby hopefully accelerating the development of old-growth forest characteristics. Redwood National Park (RNP) has been experimenting with thinning in these forest types since the 1970s. Given the interesting history of logging and restoration in RNP and the future plans for widespread thinning in this region, my thesis examined the effects …


Systematics Of Amanita (Amanitaceae, Agaricales, Basidiomycota) From The Guiana Shield And Central Africa, Kennan S. Mighell Jan 2020

Systematics Of Amanita (Amanitaceae, Agaricales, Basidiomycota) From The Guiana Shield And Central Africa, Kennan S. Mighell

Cal Poly Humboldt theses and projects

This study is a systematic assessment of ten species of ectomycorrhizal fungi of the genus Amanita (Amanitaceae, Agaricales, Basidiomycota) from the lowland tropical rainforests of the Guiana Shield and Central Africa. Fungi were collected in each of the above regions, analyzed morphologically, and compared to the literature on Amanita diversity worldwide. All species addressed herein are given full formal taxonomic descriptions including complete macro- and microscopic character profiles, habit, habitat, and distribution. Phylogenetic assessments using ribosomal DNA and protein coding genes are provided for Guiana Shield taxa, and sequence data for two non-protein coding regions, the …


The Ability Of Phyllospadix Spp., A Pair Of Intertidal Foundation Species, To Maintain Biodiversity And Ameliorate Co2 Stress In Rocky Shore Tidepools, Tayler M. Tharaldson Jan 2018

The Ability Of Phyllospadix Spp., A Pair Of Intertidal Foundation Species, To Maintain Biodiversity And Ameliorate Co2 Stress In Rocky Shore Tidepools, Tayler M. Tharaldson

Cal Poly Humboldt theses and projects

Ocean acidification (OA) is often demonstrated to have negative effects on marine organisms, but less is known about whether marine organisms can mediate OA effects. I examined relationships between surfgrass (Phyllospadix spp.), a foundation species and tidepool biodiversity, and its ability to mediate fluctuations in pH and dissolved oxygen (OA; DO) which are stressors in tidepools. I surveyed tidepools in northern California, where I quantified biodiversity, pH, and DO, and related those variables to surfgrass abundance. Laboratory and field experiments manipulating CO2 and surfgrass presence were done to examine surfgrass effects on day/night pH and DO fluctuations …


The Bee Fauna Of The Horse Mountain And Grouse Mountain Region, Humboldt County, California, Carrie Lopez Jan 2017

The Bee Fauna Of The Horse Mountain And Grouse Mountain Region, Humboldt County, California, Carrie Lopez

Cal Poly Humboldt theses and projects

Recent concerns about the ecological well-being of bee communities in California and elsewhere have increased the need for monitoring programs and studies that evaluate the impact of habitat loss and alteration on bee diversity and abundance. Such studies depend critically on the expertise of people trained in taxonomy, but their numbers have declined in recent years. My primary goal was to gain a comprehensive first-hand experience with bee identification by documenting the fauna of a previously unstudied area in the mountains of northwestern California and by writing an identification key, intended for dedicated non-specialists, to the area’s 35 species of …


Baseline Monitoring And Characterization Of Rocky Intertidal Fish Communities In Northern California, Kevin D. Hinterman Jan 2016

Baseline Monitoring And Characterization Of Rocky Intertidal Fish Communities In Northern California, Kevin D. Hinterman

Cal Poly Humboldt theses and projects

A network of new Marine Protected Areas (MPAs) has been established in northern California, covering 137 square miles of coastline, with the goal of maintaining commercially and recreationally important species and to preserve biodiversity. This is the first study in California to create a biodiversity and phylogenetic baseline of rocky intertidal fish communities within MPAs and nearby reference sites. Diversity, abundance, and size structure of intertidal fishes were compared among seven sites from Fort Bragg to Crescent City, CA during the summers and winters of 2014 and 2015. A total of 34 species were collected throughout sampling, just three less …