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Full-Text Articles in Ecology and Evolutionary Biology

Temporal Variation In Optical Properties Of Chromophoric Dissolved Organic Matter (Cdom) In Southern California Coastal Waters With Nearshore Kelp And Seagrass, Catherine D. Clark, Warren J. De Bruyn, Paige Aiona Oct 2015

Temporal Variation In Optical Properties Of Chromophoric Dissolved Organic Matter (Cdom) In Southern California Coastal Waters With Nearshore Kelp And Seagrass, Catherine D. Clark, Warren J. De Bruyn, Paige Aiona

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Optical properties of chromophoric dissolved organic matter (CDOM) were measured in surf zone waters in diurnal field studies at a Southern California beach with nearshore kelp and seagrass beds and intertidal plant wrack. Absorption coefficients (aCDOM(300 nm)) ranged from 0.35 m21 to 3.7 m21 with short-term variability<1 h, increases at ebb and flood tides and higher values (6 m21) during an offshore storm event. Spectral slopes (S) ranged from 0.0028 nm21 to 0.017 nm21, with higher values after the storm; S was generally inversely correlated with aCDOM(300 nm). 3-D excitation–emission matrix spectra (EEMs) for samples with lower S values had humic-type peaks associated with terrestrial material (A, C), marine microbial material (M) and protein peaks, characteristic of freshly produced organic material. Samples with high S values had no or reduced protein peaks, consistent with aged material. Fluorescent indexes (f450/f500 >2.5, BIX>1.1) were consistent with microbial aquatic sources. Leachates of senescent kelp and seagrass had protein and humic-type EEM peaks. After solar simulator irradiation (4 h), protein peaks rapidly photochemically degraded, humic-type peak C increased in intensity and peak M disappeared. Optical characteristics of kelp leachates were most similar to field samples, …


Effects Of El Niño On Ecological Growth Along Californian And Peruvian Coasts, Alexandra Sidun May 2015

Effects Of El Niño On Ecological Growth Along Californian And Peruvian Coasts, Alexandra Sidun

Student Scholar Symposium Abstracts and Posters

This study examines the mechanisms of El Niño to further understand the ecological effects it may have along the Californian and Peruvian coasts. El Niño is the warm phase of the El Niño Southern Oscillation (ENSO). While it is a global phenomenon, these two locations were investigated for their nearly equal and opposite conditions during storm months. California, which is in an extreme state of drought, often receives heavy rainfall during El Niño and understanding its potential effects is crucial. El Niño causes upwellings along the CA coast and warm water from the region displaces the normally cool waters along …


Effects Of Ecologically Realistic Heating Profiles On Feeding In The Intertidal Hermit Crab, Pagurus Sameulis, Paige Davis May 2015

Effects Of Ecologically Realistic Heating Profiles On Feeding In The Intertidal Hermit Crab, Pagurus Sameulis, Paige Davis

Student Scholar Symposium Abstracts and Posters

The intertidal zone is an ideal habitat to investigate effects of global warming because species living in it are very close to their physiological limits. Initial studies of invertebrate physiological responses to heat stress have employed relatively abrupt increases in temperature. My research investigates effects of ecologically more realistic temperature profiles on feeding in the intertidal hermit crab, Pagurus sameulis. Recent work in the Wright lab showed that feeding in this species is inhibited by an abrupt increase in temperature. Because temperature change in the natural environment of Pagurus is much more gradual, I hypothesize that such a gradual temperature …


Biological Degradation Of Acetaldehyde In Southern California Coastal Waters, Mary Senstad, Sovanndara Hok, Ori Barashy, Catherine D. Clark, Warren J. De Bruyn May 2015

Biological Degradation Of Acetaldehyde In Southern California Coastal Waters, Mary Senstad, Sovanndara Hok, Ori Barashy, Catherine D. Clark, Warren J. De Bruyn

Student Scholar Symposium Abstracts and Posters

Oxygenated hydrocarbons are ubiquitous in the atmosphere with levels ranging from low ppt (acetaldehyde) to low ppb (methanol). As an OH sink and an atmospheric HOx and ozone source, oxygenated hydrocarbons have a direct impact on the oxidative capacity of the atmosphere. The oceans are one of the largest sources of uncertainty in current atmospheric budget estimates of these species. A better understanding of the processes that produce and destroy these species in seawater would improve our understanding of the role of the oceans in cycling these species into or out of the atmosphere. We have measured the degradation rate …


Evaluation Of Temperature Anomalies And Ocean Productivity During The 2004 Sumatra-Andaman Earthquake, Cora Byers, Brenna Mcnabb May 2015

Evaluation Of Temperature Anomalies And Ocean Productivity During The 2004 Sumatra-Andaman Earthquake, Cora Byers, Brenna Mcnabb

Student Scholar Symposium Abstracts and Posters

The oceanic productivity of the Indian Ocean and temperature anomalies prior to the Sumatra-Andaman earthquake (MW =9.3) and tsunami (December 26th 2004) were studied. Data was obtained via NASA’s Giovanni program to determine the effect on phytoplankton (primary producers) and temperature changes over the region of the earthquake. Seasonal trends were visible in the concentrations of chlorophyll a, coccolithophores, cyanobacteria, chlorophytes, diatoms and absorption coefficient, in addition to storm trends.


Possible Precursor Events To Earthquakes And The Resulting Effects On Organic Material In The Surrounding Water Bodies, Kiyoko Nakatsui May 2015

Possible Precursor Events To Earthquakes And The Resulting Effects On Organic Material In The Surrounding Water Bodies, Kiyoko Nakatsui

Student Scholar Symposium Abstracts and Posters

Being located on the “Ring of Fire” Japan experiences many seismic events. Adding to this, it is located at the convergence of four fault lines where seismic activity will be even more frequent and severe. Although small tremors occurring in an area are indicators of an earthquake to come it only gives minutes of warning. Scientists are now trying to see if latent heat and gas release from fault lines can indicate an earthquake to come with hours or even days of warning. MODIS aqua and terra data will be analyzed in order to see if such precursors can be …


Puffs And Tufts: A Comparison Of Trichodesmium Colony Formations And Nutrient Availability Across The North Atlantic Ocean Using Remote Sensing Methods, Marc Rosenfield May 2015

Puffs And Tufts: A Comparison Of Trichodesmium Colony Formations And Nutrient Availability Across The North Atlantic Ocean Using Remote Sensing Methods, Marc Rosenfield

Student Scholar Symposium Abstracts and Posters

Trichodesmium, a genus of diazotrophic bacteria, has the capability and the population to produce a large percentage of the total oceanic N2-fixation. Though their population is known to be heavily dependent on two of the ocean’s largest limiting factors, phosphorus and iron concentrations, it is unknown what affect these factors have on the population. In this study two of the largest colony formations of Trichodesmium in the North Atlantic, tufts and puffs, are compared nutrient quality with respect to time and geographical location. Though very little nutrient in situ data was collected from the cruise, remote sensing data collected from …


Assessing Water Quality In The Gulf Of Mexico Using Remote Sensing Data., Alliyah Thomas May 2015

Assessing Water Quality In The Gulf Of Mexico Using Remote Sensing Data., Alliyah Thomas

Student Scholar Symposium Abstracts and Posters

Hypoxia, or oxygen depletion, is a process that occurs in conjunction with eutrophication. In hypoxic conditions the dissolved oxygen levels in the water column sink to unlivable conditions for the marine organisms causing them to flee or die. Despite efforts of improvement, the annual summer Gulf of Mexico dead zone continues to be a serious threat to aquatic ecosystems. The 2012 smaller than usual dead zone was a false indicator of future improvement. The 2012 dead zone decrease was connected to the drought and inability of large amounts of runoff to flow into the gulf. Water quality analysis was done …


Effects Of Human Recreational Activity On The Tameness Of Common Loons (Gavia Immer) In Northern Wisconsin, Seth Yund May 2015

Effects Of Human Recreational Activity On The Tameness Of Common Loons (Gavia Immer) In Northern Wisconsin, Seth Yund

Student Scholar Symposium Abstracts and Posters

The Common Loon (Gavia immer) is an aquatic diving bird that lives in freshwater habitats in Canada and the northern U.S.. Human activity on a loon’s resident lake may affect its fitness and behavior, yet few studies identify or quantify these effects. We modified existing techniques that measure escape distances in other species to measure tameness as the distance at which individual loons dove in response to human approach by canoe. Tameness was similar between pair members, suggesting that common lake conditions or the behavior of a mate might influence the behavior. Sex, size within sex, and human activity did …


Shifts In Attack Behavior Of An Important Kelp Forest Predator Within Marine Reserves, J. S. Berriman, M. C. Kay, D. C. Reed, A. Rassweiler, D. A. Goldstein, William G. Wright Mar 2015

Shifts In Attack Behavior Of An Important Kelp Forest Predator Within Marine Reserves, J. S. Berriman, M. C. Kay, D. C. Reed, A. Rassweiler, D. A. Goldstein, William G. Wright

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Marine reserves have become increasingly valuable tools with which to manage ecosystems. These reserves consistently restore populations of top predators, often reducing availability of their favored prey. We hypothesized that such prey reduction in reserves causes protected predators to alter their attack behavior to include less palatable prey, potentially amplifying top-down effects on community structure. To test this hypothesis, we presented the relatively unpalatable sea hare Aplysia californica to freely foraging spiny lobsters Panulirus interruptus in 4 marine no-take reserves, each paired with an adjacent fished area. We found that lobsters only attacked sea hares inside reserves, where lobster density …


On The Analysis Of Phylogenetically Paired Designs, Jennifer L. Funk, Cyril Rakovski, J. Michael Macpherson Jan 2015

On The Analysis Of Phylogenetically Paired Designs, Jennifer L. Funk, Cyril Rakovski, J. Michael Macpherson

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

As phylogenetically controlled experimental designs become increasingly common in ecology, the need arises for a standardized statistical treatment of these datasets. Phylogenetically paired designs circumvent the need for resolved phylogenies and have been used to compare species groups, particularly in the areas of invasion biology and adaptation. Despite the widespread use of this approach, the statistical analysis of paired designs has not been critically evaluated. We propose a mixed model approach that includes random effects for pair and species. These random effects introduce a “two-layer” compound symmetry variance structure that captures both the correlations between observations on related species within …


Plant Functional Traits Of Dominant Native And Invasive Species In Mediterranean-Climate Ecosystems, Jennifer L. Funk, Rachel J. Standish, William D. Stock, Fernando Valladares Jan 2015

Plant Functional Traits Of Dominant Native And Invasive Species In Mediterranean-Climate Ecosystems, Jennifer L. Funk, Rachel J. Standish, William D. Stock, Fernando Valladares

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The idea that dominant invasive plant species outperform neighboring native species through higher rates of carbon assimilation and growth is supported by several analyses of global datasets. However, theory suggests that native and invasive species occurring in low-resource environments will be functionally similar, as environmental factors restrict the range of observed physiological and morphological trait values. We measured resource-use traits in native and invasive plant species across eight diverse vegetation communities distributed throughout the five Mediterranean-climate regions, which are drought-prone and increasingly threatened by human activities including the introduction of exotic species. Traits differed strongly across the five regions. In …