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Top And Bottom Photosynthetic Activity In Nerium Oleander And Pandanus Baptistii, Ryan Arima, Jacob Gonzalez
Top And Bottom Photosynthetic Activity In Nerium Oleander And Pandanus Baptistii, Ryan Arima, Jacob Gonzalez
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Photosynthesis can be performed on any part of a leaf, yet many plants orient their leaves in different ways and are composed of different leaf anatomies. In this experiment we attempted to discover if there is a significant difference between photosynthesis on the top and bottom of Nerium oleander, a dicot that orients its dorsal face towards the sun, and Pandanus baptistii, a monocot that does not orient its leaves specifically to the sun. To perform this experiment, we used both the LI-6400 and the LiCor Integrating Sphere. With the LI-6400, we measured the photosynthetic rate of the top and …
Mechanical Strength Comparison Of Hydrated And Dehydrated Pteridium Stems, Michelle I. Kang, Kevin M. Ko, John H. Noh, Veronica R. Vega
Mechanical Strength Comparison Of Hydrated And Dehydrated Pteridium Stems, Michelle I. Kang, Kevin M. Ko, John H. Noh, Veronica R. Vega
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In this experiment, the mechanical strength of Pteridium stems was tested in two differing conditions: hydrated and dehydrated. It was hypothesized that there would be an increased performance of hydrated stems in the presence of mechanical stress. In order to test this hypothesis, twelve 20 cm pieces of stems were cut in alternation, separating those that would be dehydrated (6) with those that were hydrated (6). The dehydrated specimens were left to dry over a period of 24 hours. The diameters of each individual stem were measured to account for variation in size and remove excess variables. All twelve stems …
Fire Edge Effect On Water Potential And Stomatal Conductance In Salvia Leucophylla, Brigid N. Bergin, Paul Chung, Laura C. Miranda
Fire Edge Effect On Water Potential And Stomatal Conductance In Salvia Leucophylla, Brigid N. Bergin, Paul Chung, Laura C. Miranda
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While most plants caught in the middle of wildfires are completely incinerated, many in the edges survive despite suffering partial incineration and/or heat-induced damage. We hypothesized that heat damaged Salvia leucophylla will display a decrease in both stomatal conductance and water potential. We suspected that applying excess heat would lower the plant’s water levels and damage functional components necessary for photosynthesis, so the stomata would close to conserve water. S. leucophylla was chosen to study due to the likelihood of this widespread coastal sage to be found in the edges of wildfires in the Santa Monica Mountains. Using a heat …
The Effects Of Leaf Hydration On Light Reflectance In Salvia Leucophylla And S. Mellifera, Logan A. Schmitz, Kolina Mah-Ginn, Hayley Presthus
The Effects Of Leaf Hydration On Light Reflectance In Salvia Leucophylla And S. Mellifera, Logan A. Schmitz, Kolina Mah-Ginn, Hayley Presthus
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The presence of trichomes on a plant affect the plant’s ability to retain water; this, in turn, must affect light propagation and reflectance. It was hypothesized that a plant with a higher trichome density (Salvia leucophylla) would have a greater change in reflectance when exposed to a more aired or hydrated environment than a species with a lower trichome density (S. mellifera). Results obtained using a Unispec suggest that Salvia mellifera is more resistant to change in NDVI in response to drying and wetting. Water potential data suggest this may be related to the plant’s resistance to actual drying and …
Comparative Study Of The Mechanical Strength In Two Species Of Ferns: Polystichum Munitum And Pteridium Aquilinum, Russell P. Baetiong, Victoria M. Lekson, Olivier B. Monty
Comparative Study Of The Mechanical Strength In Two Species Of Ferns: Polystichum Munitum And Pteridium Aquilinum, Russell P. Baetiong, Victoria M. Lekson, Olivier B. Monty
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A comparative study of the mechanical strength in two species of ferns, the winter deciduous Pteridium aquilinum and the evergreen Polystichum munitum, was done. The mechanical strength of the leaf and stipe were used as a means for comparison. Additional data such as specific leaf mass (g/cm2) were also collected. The first hypothesis was that the evergreen fern would have higher leaf mechanical strength, while the second hypothesis was that there would be no difference in the mechanical strength of the stipe. The mechanical strength of the stipe was compared through the Modulus of Elasticity (MOE), while the leaf tensile …
Using The Unispec To Test The Difference In Reflectance Of The Yellow Petals Of Encelia Californica, Encelia Farinosa, And Spartium Junceum, Mariam E. Fam, Valerie E. Espinoza
Using The Unispec To Test The Difference In Reflectance Of The Yellow Petals Of Encelia Californica, Encelia Farinosa, And Spartium Junceum, Mariam E. Fam, Valerie E. Espinoza
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The reflectance spectrum of three yellow flowered species (Encelia californica, Encelia farinosa, and Spartium junceum), all grown on the coast of California, was tested to determine if reflectance among the yellow flowers was significantly different. It was hypothesized that there would be a significant difference in reflectance in the 400-700 nm wavebands for the three different species of flowers which all possess yellow petals. Using a Unispec Spectral Analysis System to obtain reflectance spectra for 12 yellow petals of three flowered species, a custom index was created in order to observe differences in the yellow color of the petals, which …
Stomatal Conductance Trends Of The Jade Plant (Crassula Ovata) In Relation To Circadian Rhythm Entrainability, Katie Cahoon, Martin Garcia, Matthew Pierga
Stomatal Conductance Trends Of The Jade Plant (Crassula Ovata) In Relation To Circadian Rhythm Entrainability, Katie Cahoon, Martin Garcia, Matthew Pierga
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The effect of an inverse light cycle on a Crassulacean acid metabolism (CAM) plant was observed in the study. CAM plants are unique in that they open their stomata at night in order to conserve water, an evolution that has come about because these plants primarily exist in very arid climates. By placing a plant in a chamber in which the lights could be programmed to turn on when it was dark out, and to turn off during normal daylight hours, the stomatal conductance of the leaves of a jade plant (Crassula ovata) were recorded several times a day over …
Is There A Correlation Between Water Potential And Mechanical Strength Of Stems Of Malosma Laurina?, William Chang, Lauren Price, Nicolas Pak
Is There A Correlation Between Water Potential And Mechanical Strength Of Stems Of Malosma Laurina?, William Chang, Lauren Price, Nicolas Pak
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The purpose of this experiment was to see if there was a correlation between water potential and the stem mechanical strength of the Malosma laurina. This experiment was conducted with the use of a Scholander-Hammel pressure chamber to find water potential and the Instron 5500 to test the mechanical strength of the stems. After analysis of the data, there was no direct correlation between water potential and the mechanical strength of stems of Malosma laurina.
Photosynthetic Advantage Of Invasive Species, Gabby Gurule-Small, Alis Sokolova, Patrick Stephens
Photosynthetic Advantage Of Invasive Species, Gabby Gurule-Small, Alis Sokolova, Patrick Stephens
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Californians have greatly benefited from the introduction of plant and animal species necessary for food or other human pursuits; however, there are many other introduced species that can wreak havoc on the state’s environment and economy. Invasive species threaten the diversity and abundance of native species by both competing for resources and causing changes to the natural habitat. We hypothesize that invasive species will have higher photosynthetic and conductance rates which contribute to their success. Through their impacts on natural ecosystems, agricultural lands, and water delivery systems, invasive species may also negatively affect human health and possibly even the economy.
The Effect Of Riparian And Arid Environments On Stomatal Conductance In Baccharis Salicifolia And Heteromeles Arbutifolia, Danalit Rangel, Vicki Mac, Ariel Lan
The Effect Of Riparian And Arid Environments On Stomatal Conductance In Baccharis Salicifolia And Heteromeles Arbutifolia, Danalit Rangel, Vicki Mac, Ariel Lan
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A riparian environment is characterized by higher moisture levels than an arid environment; therefore they have different species of plants that can adapt to their natural habitats. It is critical that we explore the characteristics plants have in relation to their native environments. We propose to test the hypothesis that Baccharis salicifolia would have a higher stomatal conductance rate to water vapor loss compared to Heteromeles arbutifolia because Baccharis salicifolia thrives in a riparian environment in which water abundance would increase stomatal opening thereby contributing to the greater conductance. Using the LI-6400, we measured the conductance rate, photosynthetic rate, CO2 …
Effect Of Ambient Air Temperature On Leaf Size In Raphanus Sativus, Matthew Fleming, Michael Mccormack
Effect Of Ambient Air Temperature On Leaf Size In Raphanus Sativus, Matthew Fleming, Michael Mccormack
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Global warming is an increasing problem in today’s society. Thus, it is important to know how plants, specifically those that are cultivated for human consumption, react to rising average temperatures. This experiment tested how the leaf size of a common crop plant, Raphanus sativus (radish), is affected by two different temperatures. It is hypothesized that as temperature rises, the leaf size will increase, giving the leaf greater ability to cool via transpiration because of an larger surface area for stomatal conductance. This hypothesis was tested by growing two samples of plants in separate incubators. One sample was grown at a …
The Relationship Between Leaf Mechanical Strength And Photosynthetic Rates, Aaron Van Loon, Brianna Manes, Taylor Stucky, Thomas Addington
The Relationship Between Leaf Mechanical Strength And Photosynthetic Rates, Aaron Van Loon, Brianna Manes, Taylor Stucky, Thomas Addington
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Photosynthesis is the process by which plants convert light energy to chemical energy, helping sustain life in the biosphere. There are many factors that affect the rate of photosynthesis such as atmospheric CO2 concentration, temperature, and sunlight. In this experiment, we attempt to determine what effect, if any, the mechanical strength of a plant has on its rate of photosynthesis. To perform this experiment we used both the LI-COR 6400 and the Instron Mechanical Testing Device. With the LI-COR we measured photosynthetic rate of our plant subjects in real time during the prime photosynthetic hours, 10-12am. The Instron allowed us …
The Effect Of Dirt On Inhibition Of Light Absorption In Musa Leaves, Lorelle Knight, Alexis Carrington, Angela French, Roxanne Barker
The Effect Of Dirt On Inhibition Of Light Absorption In Musa Leaves, Lorelle Knight, Alexis Carrington, Angela French, Roxanne Barker
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Dirt can be transported by wind, human activity and many other factors. It was hypothesized that dirt particles collected on leaves will decrease leaf reflectance and thus make the leaf less healthy. The rationale for this is that the more dirt present on the leaf, the more inhibited photons will be in reaching leaf pigments. The leaf will therefore be less healthy as it will be less able to perform photosynthesis. To test this hypothesis, eight leaf samples with varying amounts of dirt present, were collected from the plant, Musa. A Unispec spectrophotometer was used to test the reflectance of …
The Relationship Of Stomatal Conductnace To Mechanical Strength In Leaves Of Santa Monica Plants, Russell P. Mott, Steven R. Fleming, John R. Macbeth
The Relationship Of Stomatal Conductnace To Mechanical Strength In Leaves Of Santa Monica Plants, Russell P. Mott, Steven R. Fleming, John R. Macbeth
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The Santa Monica Mountains ecosystem has a high diversity of plants with different lifestyles that produce different physiological characteristics individual to all plants. Studies in Australia, another Mediterranean ecosystem, have shown that mechanical strength of leaves is relatable to soil stress. This experiment seeks to determine whether mechanical strengths of leaves correlate to stomatal conductance of leaves across different species in the Santa Monica Mountains. Four species of plants are tested for their stomatal conductance in the field, and the leaves are tested for tensile strength using Young’s Modulus for comparison across leaves. These data show that there was no …
The Effect Of Leaf Trichome Density On Stem Mechanical Strength In Salvia Leucophylla, S. Mellifera, And S. Apiana, Brieanna English, Jeff Scanlon, Anushree Mahajan
The Effect Of Leaf Trichome Density On Stem Mechanical Strength In Salvia Leucophylla, S. Mellifera, And S. Apiana, Brieanna English, Jeff Scanlon, Anushree Mahajan
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Salvia species in southern California exhibit a variety of leaf trichome densiIes. S. mellifera, S. leucophylla, and S. apiana were chosen as study organisms because they exhibit varying trichome densiIes. A UniSpec was used to measure NDVI in leaves and an Instron was used to measure stem mechanical strength. This study provides preliminary evidence that suggests plants with high leaf trichome density have less stem mechanical strength, and those with low leaf trichome density have greater mechanical strength. Data generated from this study supports the idea that this may be a general and loose trend amongst plant families similar to …
A Comparison Of Brittlebush (Encelia Farinosa) Productivity And Health During Drought And Post Rainfall, Gabi Diciolli, Karre Lawson, Anders Reimer
A Comparison Of Brittlebush (Encelia Farinosa) Productivity And Health During Drought And Post Rainfall, Gabi Diciolli, Karre Lawson, Anders Reimer
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Encelia farinosa is well adapted for drought tolerance as its leaves transform color based on water availability. We were puzzled by a question that any desert botanist must consider. How does the photosynthetic efficiency of E. farinosa fluctuate as it transitions from a state of drought to a state of soil saturation within a 72 hour period? In this experiment we looked at the effects of irrigation on the health and quantum yield of the brittlebush by looking at photosynthetic rates using the portable photosynthesis system LI-COR 6400 when applied to two leaves on a given plant and water potential …
A Comparison Of Water Potential And Mechanical Strength Of Tip And Base Leaves In Heteromeles Arbutifolia, Aaron Tsai, James Maynard
A Comparison Of Water Potential And Mechanical Strength Of Tip And Base Leaves In Heteromeles Arbutifolia, Aaron Tsai, James Maynard
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Heteromeles arbutifolia, commonly known as, Hollywood, is a plant that is extremely common in the California Chaparral ecosystem. It was observed that with Hollywood, the leaves grow on the tips of the branches predominantly. However, there are leaves that grow on the base of the branches that appear to be equally as healthy. The purpose of this investigation was to determine whether the leaves that grow at the tips of the branches or at the base of the branches were better suited to benefit the rest of the plant. Our hypothesis was that the leaves at the tips of the …
The Effects Of Water Stress On Datura Wrightii, Tony Festa, Kristin Lapointe, Sara Tandon
The Effects Of Water Stress On Datura Wrightii, Tony Festa, Kristin Lapointe, Sara Tandon
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The Santa Monica Mountains are home to a unique Mediterranean type ecosystem. Due to the effects of global warming and human disruption, the native species are beginning to decrease in population. It is imperative to observe and study the native species in order to preserve the local plant and animal life. This project focuses on the native flower Datura wrightii, specifically the causes of the opening and closing of its flowers. For Datura wrightii to be pollinated, it must be open. The results of this project will help to educate the public on how to sustain an environment in which …
The Differences In Vegetation Type On North And South-Facing Slopes, Andrew Villablanca, Katherine Mccabe, Daniel Galuhn
The Differences In Vegetation Type On North And South-Facing Slopes, Andrew Villablanca, Katherine Mccabe, Daniel Galuhn
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Our project investigated the relationship between climate change and vegetation type conversion in the Santa Monica Mountains on north and south facing slopes. Our hypothesis is that with a shift in climate towards dryer, hotter, and longer summers, and shorter and dryer winters, we will see a shift in the density of native chaparral in the Santa Monica mountains, and possibly an influx of non-native species. We tested this hypothesis by choosing three study sites that were on north/south ridgelines to simulate a dryer, harsher climate (south) and a more temperate climate (north). Using the point-quarter method to measure the …
Mechanical Strength And Hydration Level Of Heteromeles Arbutifola And Eriogonium Cinerium, Erin Hayes, Allison Naasz, Ariel Mangum
Mechanical Strength And Hydration Level Of Heteromeles Arbutifola And Eriogonium Cinerium, Erin Hayes, Allison Naasz, Ariel Mangum
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The purpose of this study was to explore the hydration levels and mechanical strength of two species native to the same area: the dry Mediterranean region of the Santa Monica Mountains. The plants in this area must make adaptations to dry and arid climates, and We will compare how they stack up against each other in terms of drought resistance. Using Hollywood (heteromeles arbutifola) and Buckwheat (Eriogonium cinerium) we studied the different hydration levels and mechanical strengths and compared them. Both H. Arbutifola and the E. Cinerium are expected to mechanically stronger when hydrated.. We also expect the H. Arbutifola …
Exploring The Hydration Levels Of Malosma Laurina At Different Elevations On A Man-Made Trail, Eric S. Taylor, Brad J. Anderson, Brandon E. Stites
Exploring The Hydration Levels Of Malosma Laurina At Different Elevations On A Man-Made Trail, Eric S. Taylor, Brad J. Anderson, Brandon E. Stites
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The purpose of this study is to examine the water potential of Malosma laurina at different elevations of a man made trail in the chapparal of the Santa Monica Mountains. Chaparral in the Santa Monica Mountains have been depleted because of human involvement effecting the chaparral ecosystem. Fire breaks and man made trails are a few of the major causes of the rapidly changing ecosystem and continues to cause stress among the plants. We are testing the effect that man made trails have on the water potential of Malosma laurina. This was measured by taking samples of Malosma laurina at …
Stem Mechanical Strength In Thinned Versus Non-Thinned Ceanothus Spinosus, Ksp, David J. Kang, Hannah Y. Choe, Melinda L. Marchiano
Stem Mechanical Strength In Thinned Versus Non-Thinned Ceanothus Spinosus, Ksp, David J. Kang, Hannah Y. Choe, Melinda L. Marchiano
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What effect does the thinning of chaparral around building structures have on plant health? More specifically, does the thinning of Ceanothus spinosus influence mechanical strength? The ability of our native chaparral to withstand environmental factors, such as the Santa Ana winds, and overall health is directly related to plant strength. Seeking to answer these questions, we hypothesized that a difference in water potential between thinned and non-thinned chaparral affects the stem mechanical strength of the plants.We believed that thinned C. spinosus due to greater hydration will be mechanically stronger than non-thinned chaparral.The knowledge of what helps chaparral to be stronger …
Effects Of 2, 4-D On Zea Maize Physiology, Caitlin Thompson, Lori Patrick, Acacia Osbourne, Katrina Brock
Effects Of 2, 4-D On Zea Maize Physiology, Caitlin Thompson, Lori Patrick, Acacia Osbourne, Katrina Brock
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Growth rate, fluorescence and stomatal conductance, in zea was examined to determine the effects of artificial auxin, 2-4-d, on common crop plants. We measured florescence, growth rate, and stomatal conductance. Low concentrations of 2,4-D increased light-adapted fluorescence, anthocyanin levels and height of zea maize. A high concentration of 2,4-D increased anthocyanin levels, but also caused decreased fluorescence and height and spindliness to occur. It appears 2,4-D is only beneficial to monocot crop plants in low quantities. We cannot accurately comment on the accuracy of our data, however, due to several potential sources of error.
Effects Of Dehydration Stress On The Dark Adapted Fluorescence (Fv/Fm) Of Giant Bladder Kelp (Macrocystis Pyrifera), J. Avery Powell, Leah Smith
Effects Of Dehydration Stress On The Dark Adapted Fluorescence (Fv/Fm) Of Giant Bladder Kelp (Macrocystis Pyrifera), J. Avery Powell, Leah Smith
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The unique semi-diurnal tide system of Southern California suspends beach wrack along the beaches for approximately six hour periods before being washed back into the ocean. It has been noted in prior research that beach wrack is an essential part of Southern California's costal ecology but not much research has been done to learn about the viability of beach wrack as it dehydrates on the beach. To better understand the viability of wrack as it travels through these hydration changes, this study tested the effect of dehydration and rehydration on the fronds of Macrocystis pyrifera as they have been partially …
The Effect Of Proximity To A Highway On The Health Of Malosma Laurina Leaves, Jessica Bermea, Haley Clayton, Jack Klobas
The Effect Of Proximity To A Highway On The Health Of Malosma Laurina Leaves, Jessica Bermea, Haley Clayton, Jack Klobas
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Due to an increase in air pollutants, heavy metal contaminates, and other adverse ecological conditions that plants near a road endure, it was hypothesized that plant species situated near a road would have a detectable decrease in photosynthetic performance when compared to plants away from the road. This investigation evaluated the in vivo photosynthetic status of two Malasma Laurina pairs with differing microhabitats, adjacent to the Pacific Coast Highway and 100 meters away from a Pacific Coast Highway. Maximum quantum yield and stomatal conductance measurements were recorded for each group. On average, the maximum quantum yield was greater on plants …
The Effect Of Hydration Status On Tensile Strength Of The Leaves Of Elymus Glaucus, Chelsie Corbett, Uri Hong, Scott Davis
The Effect Of Hydration Status On Tensile Strength Of The Leaves Of Elymus Glaucus, Chelsie Corbett, Uri Hong, Scott Davis
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Tensile strength and water potential are both factors that are essential to the life and survival of a plant. Tensile strength is a measure of the amount of force that a plant can undergo before tissue damage and breakage occur. The primary objective of this study was to examine the correlation between tensile strength and leaf hydration status, or water potential. The water potential of leaves of a monocot grass native to North America, Elymus Glaucus, commonly known as blue wildrye, was measured using the Scholander-Hammel Pressure Chamber. The tensile strength of hydrated and of dehydrated leaves was measured …
The Effects Of Agitation Upon Plant Anatomy In Phaseolus Vulgaris, Craig Sutter, Nicholas Huron
The Effects Of Agitation Upon Plant Anatomy In Phaseolus Vulgaris, Craig Sutter, Nicholas Huron
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The earthquake that struck Japan’s coast a month ago gained national attention for the damage caused by the tsunami that was caused by the earthquake. Japan’s coast is subject to multiple earthquakes each year with tremors and aftershocks following. The quakes are bound to have an effect on the growth and development of Camellia sinensis, the tea plant, which is one of the most important exports of Japan. Due to the time restraints of this project, C. sinensis were not tested, instead two week old Phaseolus vulgaris were used to show the effects of constant agitation which might mimic …
Effects Of Soil Moisture On Photosynthesis And Fluorescence In Heteromeles Arbutifolia, Ali Alyami, Colin Byrne, Katherine Currie
Effects Of Soil Moisture On Photosynthesis And Fluorescence In Heteromeles Arbutifolia, Ali Alyami, Colin Byrne, Katherine Currie
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Some plants have evolved to increase their chances of survival by being drought-adapted. Among those plant species is Heteromeles arbutifolia, native to California. Logically, the fact that Heteromeles arbutifolia tolerates the low supply of water makes this plant more likely to be within environments where the level of sun exposure is high. Thus, we hypothesized that lowering soil moisture will cause an increase in xylem pressure, causing an increase in photo-protection and florescence, and a decrease in photosynthetic rate. This has not been tested before on a native chaparral plant such as Heteromeles arbutifolia. The experiment was held …
The Effect Of Nitrogen Soil Concentration On Leaf Fluorescence In Zea Mays, Ashton Garbutt, Daniel Rossie, Anup Solsi
The Effect Of Nitrogen Soil Concentration On Leaf Fluorescence In Zea Mays, Ashton Garbutt, Daniel Rossie, Anup Solsi
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Macronutrients in the soil are essential to the growth and development of a plant. One of the most important nutrients to a plants growth is nitrogen. Nitrogen has been directly correlated to photosynthetic output in various studies and this relationship is the subject of this experiment. Since nitrogen has an effect on photosynthetic rate, there should be a correlation between nitrogen and fluorescence – a form of energy dissipation. This study attempted to show that nitrogen concentration in the soil is inversely proportional to fluorescence of the plant because the more nitrogen in the soil, the more energy should be …
Is There A Relationship Between Water Potential And The Mechanical Strength Of Salix Lasiolepis?, William Cohen, Gina Fitzgerald, Joseph Liao
Is There A Relationship Between Water Potential And The Mechanical Strength Of Salix Lasiolepis?, William Cohen, Gina Fitzgerald, Joseph Liao
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