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Full-Text Articles in Life Sciences

Glycolic Acid Utilization In Two Species Of Marine Bacteria, Erik S. Timsak Aug 2019

Glycolic Acid Utilization In Two Species Of Marine Bacteria, Erik S. Timsak

STAR Program Research Presentations

Interactions between bacteria and phytoplankton are crucial for the cycling of organic matter in marine environments. Around 50% of organic carbon taken up by marine bacteria is converted into inorganic carbon. The uptake of organic carbon by marine bacteria exuded from phytoplankton is a key factor in regulating the marine carbon cycle. One such molecule that is exuded by phytoplankton and then uptaken by marine bacteria is called glycolate - the anion of glycolic acid, a two caron molecule. Glycolate is exuded by phytoplankton during photorespiration and 10-50% of dissolved organic carbon in marine environments is comprised of glycolate. Additionally, …


Effects Of Habitat Restoration On Soil Retention On Santa Rosa Island, Michael Perez, Kathryn Mceachern, Ken Niessen Jan 2017

Effects Of Habitat Restoration On Soil Retention On Santa Rosa Island, Michael Perez, Kathryn Mceachern, Ken Niessen

STAR Program Research Presentations

Ranching began on Santa Rosa Island in the 1840’s, consequently introducing nonnative megafauna that put novel selective grazing pressures on endemic plant species. Their movement patterns also altered substrate integrity as the land became denuded of any stabilizing vegetation. Dense groves of island oak (Q. tomentella) are known to aid in sediment deposition and retention. The groves also function to collect water during periods of intense fog common to the island. This experiment sought to determine whether sediment is being lost or deposited on a ridge in the middle of the island containing a grove of Q. tomentella …


Weights And Balances: Integrating Models For Prevention And Response To Southern California Offshore Oil Spills, Carmen Watts Clayton, Amoret Bunn Oct 2016

Weights And Balances: Integrating Models For Prevention And Response To Southern California Offshore Oil Spills, Carmen Watts Clayton, Amoret Bunn

STAR Program Research Presentations

Licensing offshore oil and gas reserves in the United States waters are overseen by the U.S. Department of the Interior’s Bureau of Safety and Enforcement (BSEE). The licensing application includes planning for any worst-case oil spill scenario between BSEE and the applicant based on lessons learned from historic offshore spills such as the Deepwater Horizon (2010), Exxon Valdez (1989), and the Union Oil Platform Blowout (1969). The process for planning to respond to oil spills involves coordination with multiple agencies, trustees, and stakeholders to ensure that oil spill responses consider multiple factors, including ecologically sensitive species, commercial transportation and fisheries, …


Studying The Effects Of Serpentine Soil On Adapted And Non-Adapted Species Using Arduino Technology, Kiana Saniee, Edward Himelblau, Brian Paavo Oct 2016

Studying The Effects Of Serpentine Soil On Adapted And Non-Adapted Species Using Arduino Technology, Kiana Saniee, Edward Himelblau, Brian Paavo

STAR Program Research Presentations

Abstract: Serpentine soils are formed from ultramafic rocks and are represent an extreme environment for plants. Serpentine soils are unique in that they carry high concentrations of heavy metals, are nutrient deficient, particularly in calcium, and have poor water retention capabilities. Although these soils constitute harsh conditions for plant growth, there are a number of species that are adapted and even endemic to serpentine soil. Water retention by commercial potting mix was compared with serpentine soil. Also, serpentine adapted and non-adapted species were grown in both soil treatments and physiological data were collected. We used the Arduino electronic platform to …


To Fish Or Not To Fish? What Effect Do California’S Marine Protected Areas Have On Up-And-Coming Kellet’S Whelk Fishery?, Jennifer Greene Oct 2016

To Fish Or Not To Fish? What Effect Do California’S Marine Protected Areas Have On Up-And-Coming Kellet’S Whelk Fishery?, Jennifer Greene

STAR Program Research Presentations

Kellet’s whelk, Kelletia kelletii, were observed at sample sites throughout their range from Baja California, Mexico, to Monterey, CA to determine patterns of population density. Sample sites in each region were either located within California marine protected areas where take of the Kellet’s whelk in prohibited, or in non-protected areas where the whelks can be fished both commercially and recreationally. Kellet’s whelk population density was compared between all MPA and non-MPA sample sites. These mean densities were also found for sites in Santa Barbara and San Diego near active fishing ports and compared to data from the same sites collected …


Effects Of Soil Erosion Barriers On Percent Cover And Sediment Size, Michael Perez Aug 2016

Effects Of Soil Erosion Barriers On Percent Cover And Sediment Size, Michael Perez

STAR Program Research Presentations

Ranching began on Santa Rosa Island in the 1840’s, introducing nonnative megafauna that put selective grazing pressures on endemic species. Dense groves of island oak (Q. tomentella) are aid in sediment deposition and retention. A current restoration effort, involved installing soil erosion barriers, known as wattles, to prevent sediment from being lost upslope and recruit plant growth whose root systems could further stabilize the slope. This experiment was designed to compare percent cover of vegetation growth in areas with and without soil erosion barriers. This was done using the line intercept method (n=42) on three meter transects, measuring …


Sediment Loss Of Santa Rosa Island Slopes: An Erosional Study, Michael Perez Aug 2015

Sediment Loss Of Santa Rosa Island Slopes: An Erosional Study, Michael Perez

STAR Program Research Presentations

Ranching began on Santa Rosa Island in the 1840’s, consequently introducing nonnative megafauna that put novel selective grazing pressures on endemic plant species. Their movement patterns also altered sediment integrity as the land was denuded of any stabilizing vegetation. Dense groves of island oak (Q. tomentella) are known to aid in sediment deposition and retention. The groves also function to collect water during periods of intense fog that are common to the island. This experiment sought to quantify the volume of sediment that has been lost on a south facing slope in the middle of the island that …


Do Marine Protected Areas Affect Emerging Fisheries Population Density?, Jennifer Greene, Katherine O. Grady, Crow White, Danielle Zacherl Aug 2015

Do Marine Protected Areas Affect Emerging Fisheries Population Density?, Jennifer Greene, Katherine O. Grady, Crow White, Danielle Zacherl

STAR Program Research Presentations

Kellet’s whelk, Kelletia kelletii, were observed at sample sites throughout their range from Baja California, Mexico, to Monterey, CA to determine patterns of population density. Sample sites in each region were either located within California marine protected areas where take of the Kellet’s whelk in prohibited, or in non-protected areas where the whelks can be fished both commercially and recreationally. Kellet’s whelk population density was compared between all MPA and non-MPA sample sites. These mean densities were also found for sites in Santa Barbara and San Diego near active fishing ports and compared to data from the same sites collected …


Feeding Ecology Of Delta Smelt During A Seasonal Pulse Of Turbidity, William A. Hilton, Aaron Johnson, Wim Kimmerer Aug 2013

Feeding Ecology Of Delta Smelt During A Seasonal Pulse Of Turbidity, William A. Hilton, Aaron Johnson, Wim Kimmerer

STAR Program Research Presentations

The delta smelt (Hypomesus transpacificus) is a small, pelagic fish endemic to the San Francisco Estuary (SFE) and protected under federal and state endangered species acts. This study examines the diet of adult delta smelt during their spawning migration in the winters of 2010 and 2012. Delta smelt and their zooplankton prey were sampled concurrently during a seasonal pulse of turbidity at sites along their migratory route from the low salinity zone in Suisun Bay to the fresher waters of the Sacramento/San Joaquin Delta. Gut contents were identified to the lowest possible taxon and counted, along with zooplankton …


The Large Genome Constraint Hypothesis: Evolution, Ecology And Phenotype, Charles A. Knight, Nicole A. Molinari, Dmitri A. Petrov Jan 2005

The Large Genome Constraint Hypothesis: Evolution, Ecology And Phenotype, Charles A. Knight, Nicole A. Molinari, Dmitri A. Petrov

Biological Sciences

Background and Aims If large genomes are truly saturated with unnecessary ‘junk’ DNA, it would seem natural that there would be costs associated with accumulation and replication of this excess DNA. Here we examine the available evidence to support this hypothesis, which we term the ‘large genome constraint’. We examine the large genome constraint at three scales: evolution, ecology, and the plant phenotype.

Scope In evolution, we tested the hypothesis that plant lineages with large genomes are diversifying more slowly. We found that genera with large genomes are less likely to be highly specious – suggesting a large …