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Full-Text Articles in Life Sciences

Modifying Succession: A History Of Vegetation Alliances On Swanton Pacific Ranch, Jill Wilson O'Connor Jun 2019

Modifying Succession: A History Of Vegetation Alliances On Swanton Pacific Ranch, Jill Wilson O'Connor

Master's Theses and Project Reports

This thesis conducts historical research into Swanton Pacific Ranch in the County of Santa Cruz, an interdisciplinary facility for education and research managed by Cal Poly’s College of Agriculture, Food and Environmental Sciences. The study seeks to determine whether there have been discernable changes in vegetation alliances (communities), spatially or in type, within a 110-acre Study Area from the early twentieth century to the present day and how the changes compare with other similar historical analyses in California. Historical farming and ranching uses of the area are researched, and two family case studies are presented as paradigms of potential ...


Leaf Functional Traits As Predictors Of Drought Tolerance In Urban Trees, Sophia Huang Jun 2019

Leaf Functional Traits As Predictors Of Drought Tolerance In Urban Trees, Sophia Huang

Master's Theses and Project Reports

The services that urban trees provide to human society and the natural environment are widely recognized, but urban trees are in jeopardy due to climate change and urban stressors. With drought as a major threat in many areas, it is important for the future of urban forestry to select species composition based upon performance under water stress. Certain leaf functional traits can help horticulturalists more accurately predict water usage of urban trees. Comprehension through rigorous experimentation is lacking, partly due to the thousands of mostly exotic species. Previous studies suggest that species whose leaves have a denser arrangement of smaller ...


Quantifying The Environmental Performance Of A Stream Habitat Improvement Project, Cody Morse Aug 2018

Quantifying The Environmental Performance Of A Stream Habitat Improvement Project, Cody Morse

Master's Theses and Project Reports

River restoration projects are being installed worldwide to rehabilitate degraded river habitat. Many of these projects focus on stream habitat improvement (SHI), and an estimated 60%of the 37,000 projects listed in the National River Restoration Science Synthesis Program focus on SHI for salmon and trout species. These projects frequently lack a sufficient monitoring program or account for the environmental costs associated with SHI. The present study used life cycle assessment (LCA) techniques and topographic effectiveness monitoring to quantify environmental costs on the basis of geomorphic change. This methodology was a novel approach to assessing the cost-benefit relationship of ...


The Population Genetics Of Morro Bay Eelgrass (Zostera Marina), Julia Gardner Harencar Jun 2017

The Population Genetics Of Morro Bay Eelgrass (Zostera Marina), Julia Gardner Harencar

Master's Theses and Project Reports

Seagrass populations are in decline worldwide. Zostera marina (eelgrass), one of California’s native seagrasses, is no exception to this trend. In the last 8 years, Morro Bay, California has lost 95% of its eelgrass. Eelgrass is an ecosystem engineer, providing important ecosystem services such as sediment stabilization, nutrient cycling, and nursery habitats for fish. The failure of recent restoration efforts necessitates a better understanding of the causes of eelgrass decline in this estuary. Previous research on eelgrass in California has demonstrated a link between population genetic diversity and eelgrass bed health, ecosystem functioning, and resilience to disturbance and extreme ...


Araucaria In The Urban Landscape: A Novel Leaning Pattern And Evidence Of Cultivated Hybridization, Jason W. Johns Jan 2017

Araucaria In The Urban Landscape: A Novel Leaning Pattern And Evidence Of Cultivated Hybridization, Jason W. Johns

Master's Theses and Project Reports

Our understanding of the natural world is constantly evolving and strengthening as more observations are made and experiments are performed. For example, we understand that tree stems grow toward the light (positive phototropism; Darwin 1880, Loehle 1986, Christie et al. 2013) and against gravity (negative gravitropism; Knight 1806, Hashiguchi et al. 2013). We also know that plants respond to mechanical stimulus and perturbation (thigmotropism; Braam 2005). Genes and their resulting proteins have been described to uncover some of the mechanisms for these environmental responses, but relatively speaking, we have just scratched the surface (Wyatt et al. 2013). While the discovery ...


Evaluating The Myth Of Allelopathy In California Blue Gum Plantations, Kristen Marie Nelson Jun 2016

Evaluating The Myth Of Allelopathy In California Blue Gum Plantations, Kristen Marie Nelson

Master's Theses and Project Reports

It is widely accepted that allelopathy is not only significant, but more or less singular, in the inhibition of understory vegetation in California Eucalyptus globulus (blue gum) plantations. However, there is no published documentation of allelopathy by blue gums against California native species. Here, we present evidence that germination and early seedling growth of five California native species are not inhibited by chemical extracts of blue gum foliage, either at naturally-occurring or artificially concentrated levels. In the greenhouse, seeds were germinated in field-collected soil from mature blue gum plantations and the adjacent native, coastal scrub communities. In petri plates, seeds ...


The Effects Of Foliar Nutrient Applications On Split, Yield, And Internal Fruit Quality Of 'Wonderful' Pomegranate (Punica Granatum L.), John Matthew Chater Dec 2015

The Effects Of Foliar Nutrient Applications On Split, Yield, And Internal Fruit Quality Of 'Wonderful' Pomegranate (Punica Granatum L.), John Matthew Chater

Master's Theses and Project Reports

Fruit split is the most important physiological disorder in pomegranate production, causing devastating crop losses worldwide. Foliar nutrient applications have been used experimentally to mitigate pomegranate fruit split but none have been conducted using the industry standard cultivar, Wonderful, and little is known about the effects of foliar nutrient applications on pomegranate. Additionally, investigations into putative health benefits of pomegranate fruit have increased interest in its production but limited evidence exists regarding effects of agricultural practices such as foliar fertilizer applications on internal fruit quality. ‘Wonderful’ pomegranate trees at 2 commercial orchards were treated with foliar applications of ZnSO4 ...


Photosynthetic Thermal Tolerance And Recovery To Short Duration Temperature Stress In Desert And Montane Plants: A Comparative Study, David William Gallagher Jun 2014

Photosynthetic Thermal Tolerance And Recovery To Short Duration Temperature Stress In Desert And Montane Plants: A Comparative Study, David William Gallagher

Master's Theses and Project Reports

  • Climate change models predict an increase in frequency and amplitude of extreme weather events, including heat waves. To better predict how the composition and distribution of plant assemblages might respond to these changes in temperature, it is important to understand how species currently respond to these extremes. Photosynthetic thermal tolerance (T25)and photosynthetic recovery (RT25) were quantified in 27 species. We also studied the relationships between T25, RT25 and leaf mass per area (LMA). Leaf temperature was also monitored in the field.
  • Leaves used in this study were collected from two distinct environments representing desert and ...


Mapping Plant Biodiversity Hotspots At The County Scale: A New Tool For Establishing Resource Conservation Strategies, Kristie Haydu Jun 2012

Mapping Plant Biodiversity Hotspots At The County Scale: A New Tool For Establishing Resource Conservation Strategies, Kristie Haydu

Master's Theses and Project Reports

Myers first identified the world’s 25 biodiversity hotspots and pioneered innovative ideas about the usefulness of biodiversity models for establishing long-term resource conservation strategies at global scales. Since Myers, most of the subsequent studies using hotspot science for biodiversity modeling have used large spatial scales like countries, provinces or states, and other biogeoraphic regions. The California Floristic Province continues to be one of the recognized global biodiversity hotspots. Our study site, San Luis Obispo County is within this hotspot and we created a map of plant biodiversity hotspots at the county scale using GIS technology. We wanted to determine ...


Classifying And Mapping Diversity In A Species-Poor System: The Mangrove Meta-Community Of Laguna Chacahua National Park, Oaxaca, Mexico, Elizabeth Kay Weisgerber Sep 2011

Classifying And Mapping Diversity In A Species-Poor System: The Mangrove Meta-Community Of Laguna Chacahua National Park, Oaxaca, Mexico, Elizabeth Kay Weisgerber

Master's Theses and Project Reports

ABSTRACT

Classifying and Mapping Diversity in a Species-Poor System: the mangrove meta-community of Laguna Chacahua National Park, Oaxaca, Mexico

by

Elizabeth Kay Weisgerber

Both field transects and imagery grid plots were analyzed with the goal of creating a community classification map for the mangrove forest of Parque Nacional Lagunas de Chacahua. In total, data was collected in 49 sites throughout the park, recording measures such as DBH, basal area, estimated dominance, frequency, cover and relative dominance. Field locations were marked and georeferenced with a GPS and grid plots overlaid on satellite imagery of the park were generated via a random ...


Environmental Variables Influencing The Severity Of Pierce’S Disease In California Grapevines, Christopher James Boisseranc Jun 2010

Environmental Variables Influencing The Severity Of Pierce’S Disease In California Grapevines, Christopher James Boisseranc

Master's Theses and Project Reports

This project was designed to correlate environmental variables with the development of Pierce’s Disease (PD), an infection caused by the gram negative bacterium Xylella fastidiosa (Xf), in grapes (Hopkins et al. 2002). PD is one of the most difficult crop pathogens to manage because it is vectored by insects and its continued presence in the vine is usually fatal. PD is influenced by the interaction of host, disease and vector, and probably many other environmental variables. The general objective was to study and identify the most important variables involved in the expression of Pierce’s Disease.

Over a two ...