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Full-Text Articles in Life Sciences
Climate Change And Drought In California, Jake Szarzynski, Wei Zhang, Brennan Tatem
Climate Change And Drought In California, Jake Szarzynski, Wei Zhang, Brennan Tatem
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we believe that there is a correlation between the increasing frequency and duration of droughts in California and climate change. The first step to solving any problem, such as a drought, is to identify the cause of the problem. As a result of the research conducted, we can determine that it is possible that climate change is a leading cause to droughts. We hope that by providing evidence that climate change is causing droughts, people will become aware that climate change does have negative results that we experience on a daily basis. We used several different scholarly resources when conducting …
Measuring Photosynthesis To Evaluate Photoprotection By Anthocyanins In Malosma Laurina, Jorge Bojorkez-Calderon, Hannah Imson
Measuring Photosynthesis To Evaluate Photoprotection By Anthocyanins In Malosma Laurina, Jorge Bojorkez-Calderon, Hannah Imson
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The purpose of this investigation was to observe the differences between the photosynthetic rates and photo-protection of young, red, juvenile leaves of Malosma laurina, and compare it to young, green leaves. To accomplish this, the open-system of Li-6400 XT was brought out into the field to a shrub of Malosma laurina that was flourishing and had both red and green leaves present. Then, data of fluorescence, photosynthetic rate, and conductance was taken from both red leaves and green leaves, and the photosynthetic rates were compared. Through this investigation, we were able to quantify that in young, red leaves, which had …
Measuring Water Potential Among Crassula Ovata And Heteromeles Arbutifolia, Monét Mcnally, Stephanie Yakupitiyage, Jamille Lockhart
Measuring Water Potential Among Crassula Ovata And Heteromeles Arbutifolia, Monét Mcnally, Stephanie Yakupitiyage, Jamille Lockhart
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Chaparral shrubs are known for their abilities to withstand dry environments. Both the California native C3 plant, Heteromeles arbutifolia, also known as Hollywood, and the CAM plant, Crassula ovata, also know as a Jade plant, have the ability to thrive under a Mediterranean-like climate region. However, during severe cases of drought one plant may better adapted than the other. The purpose of this experiment is to determine whether Heteromeles arbutifolia or Crassula ovata is better able to withstand drought by measuring the dehydration rate. We calculated the leaf-area to mass ratio and the change in water potential of each species …
Relating Leaf Temperature On Malosma Laurina To Leaf Proximity From Soil, Brooks O'Hea, Kevin Morgan
Relating Leaf Temperature On Malosma Laurina To Leaf Proximity From Soil, Brooks O'Hea, Kevin Morgan
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The Santa Monica Mountains are home to countless vegetation and plant species, many of which have been forced to adapt to southern California’s stressful environment. With recent droughts and a steady change in climate, an increase in leaf temperature within some species in the Santa Monica Mountains has been observed. One prominent plant found within the mountain range is the malosma laurina, or laurel sumac, the only species of the malosma genus. Malosma laurina is a perfect example of a specie adapting to its stressful environment. Constant brush and shrub fires within the chaparral area where it commonly grows have …
Foliar Water Uptake And Resurrection: Mechanisms Of Drought Tolerance In Eight Species Of Ferns In The Santa Monica Mountains, Victoria M. Lekson
Foliar Water Uptake And Resurrection: Mechanisms Of Drought Tolerance In Eight Species Of Ferns In The Santa Monica Mountains, Victoria M. Lekson
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In a region where drought is severe, ecological surveys provide insight into the adaptations of organisms living on the edge of survival. In this study, the mechanisms of drought tolerance for eight species of ferns in the Santa Monica Mountains were assessed with a focus on foliar water uptake and resurrection strategies. We find that species are significantly different (P < 0.001) in their ability to absorb water through leaves (assessed gravimetrically) and correlate this to minimum seasonal water potential and hydrophobicity of leaf surfaces. Secondly, we irrigated Pentagramma triangularis in the field and tracked chloroplast recovery. We found possible evidence of embolism reversal. Taken together, this study explored the methods of survival of the most ancient family of vascular plants.
Differential Survival Of Chaparral Shrub Species In Response To Severe Drought, Hannah Dario
Differential Survival Of Chaparral Shrub Species In Response To Severe Drought, Hannah Dario
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In this experiment, we examined how the plants in the Santa Monica Mountains are responding to the driest period in recorded history for California. Our hypothesis was that plant species with the deepest roots would have highest survivorship. We thought this because deep-rooted shrubs will have greater access to soil moisture. This hypothesis was tested by collecting data on plant survival, in a mixed chaparral stand, containing eleven species, growing in the Green Valley Preserve off of Stunt road, in the Santa Monica Mountains. The chaparral stand was 21 years old, having last burned in 1993 (Old Topanga Canyon Fire). …
Comparison Of Downstream Cell Survival Responses In Huvecs And Hlecs During Vegf Signaling, Haley M. Smith, Thomas Vandergon
Comparison Of Downstream Cell Survival Responses In Huvecs And Hlecs During Vegf Signaling, Haley M. Smith, Thomas Vandergon
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Angiogenesis and lymphangiogenesis are vital processes that allow the formation of new blood and lymph vessels from existing vessels to bring oxygen and vital nutrients to the body. These processes occur through Vascular Endothelial Growth Factor (VEGF) signaling to vascular endothelial cells where they bind to cell surface receptors. There are a variety of responses to these signals including cell proliferation, migration and survival. In this study Human Umbilical Vascular Endothelial Cells (HUVECs) and Human Lymphatic Endothelial Cells (HLECs) were stressed with Tunicamycin and supplemented with various VEGF signals to examine how cell survival pathways might respond during VEGF signaling. …
A Comparison Of Water Availability In Coastal Live Oak (Quercus Agrifolia) And California Bay (Umbellularia Californica) At Top And Bottom Of Hillsides At Malibu Creek State Park, California, Jake Szarzynski, Marley Biyendolo, Jeremy Goldenetz, Ann Alcazar
A Comparison Of Water Availability In Coastal Live Oak (Quercus Agrifolia) And California Bay (Umbellularia Californica) At Top And Bottom Of Hillsides At Malibu Creek State Park, California, Jake Szarzynski, Marley Biyendolo, Jeremy Goldenetz, Ann Alcazar
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This investigation serves to show whether moisture content is different in plants at the top of hills versus bottom of hills, specifically comparing values of Quercus agrifolia and Umbellularia californica in Malibu Creek State Park. By acquiring six branches of each species on a hill at intervals of twenty feet, the moisture content can be obtained and analyzed by using the Scholander Hammel pressure chamber. This allows us to determine whether there is a correlation between moisture content and plant position on hills.
Varying Carbon Dioxide Levels And Its Effects On Malsoma Laurina’S Photosynthetic Rate, John A. Lawlor, Dustyn T. Zierman-Felix, Michael P. Schlagel
Varying Carbon Dioxide Levels And Its Effects On Malsoma Laurina’S Photosynthetic Rate, John A. Lawlor, Dustyn T. Zierman-Felix, Michael P. Schlagel
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The Keeling Curve has displayed an exponential increase in carbon dioxide within the earth’s atmosphere since the late 1950’s. Scientists have heatedly debated the effects that will occur as a result of this relatively new phenomenon (since the Industrial Revolution of America). We tested the effect of increased carbon dioxide levels on plant life, Malosma laurina, in particular. Our experiment involved the application of 400 PPM of carbon dioxide into different specimens of M. laurina and 800 PPM of carbon dioxide into the same specimens. We then recorded the rate of photosynthesis, conductance results, and levels of internal carbon dioxide. …
Difference In Water Status Between Oak Trees (Quercus Berberidifolia) With Brown And Green Leaves During Severe Drought, Mia Bryant, Hannah Dario, Cameron Kline
Difference In Water Status Between Oak Trees (Quercus Berberidifolia) With Brown And Green Leaves During Severe Drought, Mia Bryant, Hannah Dario, Cameron Kline
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In this experiment, we examined cavitation in Quercus berberidifolia plants. We hypothesized that as the amount of water stress increases, then the pressure to cause embolism will decrease. We thought this because as a plant loses more water, the more air bubbles will form within the plant and therefore the pressure to cause this will decrease. We tested this hypothesis by comparing dry Quercus berberidifolia to more hydrated Quercus berberidifolia in Tapia Park, near Malibu, California. We measured and compared these plants by the use of the Scholander Pressure chamber and a parometer. In the end, we discovered that our …
Impact Of Reclaimed Water On Photosynthetic Performance In Green Bark Ceanothus (Ceanothus Spinosus), Erika De Leener, Michael L. Gribble, Joshua D. Volkmar, Luo J. Zhao
Impact Of Reclaimed Water On Photosynthetic Performance In Green Bark Ceanothus (Ceanothus Spinosus), Erika De Leener, Michael L. Gribble, Joshua D. Volkmar, Luo J. Zhao
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The sprinkled water on the campus of Pepperdine University is primarily reclaimed water from sinks, toilets and showers on campus. The water is treated with micro bacteria and sand rocks to remove larger particles, smaller nitrogen containing compounds, excess nutrients and human pathogens. The Mediterranean weather in Southern California is characterized by dry summers, and watering plants by reclaimed water helps relieve the water stress in the community. However, the reclaimed water might distort the normal physiology of native plants on campus. We hypothesize that because nitrogen containing compounds cannot be efficiently removed by micro bacteria, higher nitrogen content in …
Post-Fire Recovery Of Juglans Californica In Sycamore Canyon: Water Potential And Site Characterization, Ariel Lan, Caitlin Thompson, Victoria Lekson
Post-Fire Recovery Of Juglans Californica In Sycamore Canyon: Water Potential And Site Characterization, Ariel Lan, Caitlin Thompson, Victoria Lekson
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Our study focused on post-fire recovery in the California Black Walnut, Juglans californica. Our study was conducted Sycamore Canyon, an area of the Santa Monica Mountain Range recently damaged by the April 2013 fires. Part of our study focused on water potential and water stress among J. californica; we examined differences in the water potentials of mature, unburned trees and resprouts which have grown since the fires in April. We found that mature trees have a significantly higher water potential than sprouts, either epicormic or basal, which indicates that they are better equipped to handle water stress. We also found …
Post-Fire Recovery Of Juglans Californica In Sycamore Canyon: Vessel Length, Shading, Water Use Efficiency And Water Status, Victoria Lekson, Anushree Mahajan
Post-Fire Recovery Of Juglans Californica In Sycamore Canyon: Vessel Length, Shading, Water Use Efficiency And Water Status, Victoria Lekson, Anushree Mahajan
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In April 2013, Sycamore Canyon experienced a major wildfire. This study investigates post-fire recovery of two types of resprouts, basal and epicormic, and compares multiple parameters to mature unburned Juglans californica. In this study, we investigate the influence of time of day on the post-fire water potential of mature unburned plants versus burned Juglans californica epicormic and basal resprouts. One way ANOVA test reveals p
The Effect Of Freezing Conditions On Xylem Diameter Of Malosma Laurina And Umbellularia Californica In The Santa Monica Mountains, Nicole A.P.M.K.O.M. Nakamatsu, Theadora V. Ordog, Kaitlyn E. Sauer
The Effect Of Freezing Conditions On Xylem Diameter Of Malosma Laurina And Umbellularia Californica In The Santa Monica Mountains, Nicole A.P.M.K.O.M. Nakamatsu, Theadora V. Ordog, Kaitlyn E. Sauer
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Temperature variations in the Santa Monica Mountains are drastic at times, which may be affecting the local plants. To determine the repercussions of these variations in temperature, we measured the xylem diameters of freezing and non-freezing Malosma laurina and Umbellularia californica. U. californica was chosen because it has a large xylem diameter, yet is known to survive freezing conditions. We thought that this plant could provide the most significant results to prove or disprove our hypothesis. M. laurina was chosen because it is abundant in the Santa Monica Mountains and has different physical dimensions than U. californica. Smaller xylem diameters …