Marine Biology Commons^™

Ecological Resilience Indicators For Salt Marsh Ecosystems, Scott T. Allen, Camille L. Stagg, Jorge Brenner, Kathleen L. Goodin, Don Faber-Langendoen, Christopher A. Gabler, Katherine Wirt Ames

School of Earth, Environmental, & Marine Sciences Faculty Publications

Salt marshes are coastal ecosystems within the intertidal zone, characterized by hypoxic, saline, soil conditions and low biodiversity. Low diversity arises from frequent disturbance and stressful conditions (i.e., high salinity and hypoxia), where vegetative reproduction and low competition result in mostly monotypic stands, with some differences in plant community influenced by flooding regime (described below). While there are several types of salt marshes in the Northern Gulf of Mexico (NGoM), ranging from low to high salt marshes and salt flats (Tiner, 2013), Spartina alterniflora–dominated salt marshes in the Coastal and Marine Ecological Classification Standard (CMECS) Low and Intermediate Salt Marsh …

First Record Of The Yellowfin Soldierfish, Myripristis Chryseresjordan & Evermann, 1903, In The Easter Island Ecoregion, Erin E. Easton, Javier Sellanes, Matthias Gorny

School of Earth, Environmental, & Marine Sciences Faculty Publications

Myripristis chryseres Jordan & Evermann, 1903, is recorded for the first time in the Easter Island Ecoregion. Two specimens were observed swimming along a rock cliff and entering a cavern at ∼163 m depth near the peak of Pukao seamount, located ∼85 km (46 nm) west of Easter Island. This report expands the geographic range of M. chryseres eastward by ∼3,800 km and is the first report of the species for the eastern Pacific. It is unclear whether this new record is indicative of a relatively recent range expansion or a lack of visual surveys in the region, which …

Preliminary Multivariate Comparison Of Coral Assemblages On Carbonate Banks In The Western Gulf Of Mexico, Rebekah E. Rodriguez, Erin E. Easton, Thomas C. Shirley, John W. Tunnell, David Hicks

School of Earth, Environmental, & Marine Sciences Faculty Publications

Hermatypic corals flourished on reefs in the Gulf of Mexico (GOM) in the late Pleistocene and early Holocene. Today, many of these relict reefs are mesophotic banks that have unique coral assemblages and provide critical habitat; however, the South Texas Banks (STB) lack quantitative surveys. Therefore, we used a remotely operated vehicle to conduct quantitative surveys of 5 banks: Baker, Aransas, Dream, Blackfish Ridge, and Harte. Coral communities, based on estimated coral densities (colonies/m2), significantly differed among banks for terraces, slopes, and overall (combined terrace and slope) communities for most banks examined. Within banks, terrace and slope communities significantly differed …

Validating Sidescan Sonar As A Fish Survey Tool Over Artificial Reefs, Michael A. Bollinger, Richard Kline

School of Earth, Environmental, & Marine Sciences Faculty Publications

Visual observation methods via SCUBA are commonly used to survey artificial reef fish, although conditions in the Gulf of Mexico often make surveys difficult or even dangerous for divers. In this study, sidescan sonar was used to quantify water-column fish abundance and was compared to the established visual observation methods on SCUBA over four reef sites. Calibrated intensity values measured from sidescan sonar echo returns were used to estimate fish body length and to calculate scaled biomass (g/m2 reef) from a pooled fish length–weight relationship of commonly observed reef fish in the area. Sidescan sonar methods were equivalent to SCUBA …

Capturing Species-Level Drought Responses In A Temperate Deciduous Forest Using Ratios Of Photochemical Reflectance Indices Between Sunlit And Shaded Canopies, Taehee Hwang, Hamed Gholizadeh, Daniel A. Sims, Kimberly A. Novick, Edward R. Brzostek, Richard P. Phillips, Daniel T. Roman, Scott M. Robeson, Abdullah F. Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

Highlights

• We examine capability of spectral indices to capture isohydric/anisohydric behavior.

• We used both in-situ spectral measurements and multi-angle MODIS images.

• Only PRI could capture species-level drought responses.

• This study presents a step forward to directly mapping emergent isohydricity.

Abstract

To classify trees along a spectrum of isohydric to anisohydric behavior is a promising new framework for identifying tree species' sensitivities to drought stress, directly related to the vulnerability of carbon uptake of terrestrial ecosystems with increased hydroclimate variability. Trees with isohydric strategies regulate stomatal conductance to maintain stationary leaf water potential, while trees with anisohydric strategies allow leaf …

Nitrate Leaching From Sand And Pumice Geomedia Amended With Pyrogenic Carbon Materials, James Jihoon Kang, Marissa Davila, Sergio Mireles, Jungseok Ho

School of Earth, Environmental, & Marine Sciences Faculty Publications

There is increasing interest in using pyrogenic carbon as an adsorbent for aqueous contaminants in stormwater. The objective of this study was to investigate pyrogenic carbon materials as an amendment to geomedia to reduce nitrate leaching. Batch adsorption and column experiments were conducted to evaluate the performance of a commercial activated carbon and two biochars incorporated (5% by weight) into sand and pumice columns. The batch adsorption with 50 mg L−1 of nitrate solution showed that only activated carbon resulted in a substantial adsorption for nitrate up to 41%. Tested biochars were not effective in removing aqueous nitrate and even …

A Novel Diffuse Fraction-Based Two-Leaf Light Use Efficiency Model: An Application Quantifying Photosynthetic Seasonality Across 20 Ameriflux Flux Tower Sites, Hao Yan, Shao-Qiang Wang, Kai-Liang Yu, Bin Wang, Qin Yu, Gil Bohrer, Dave Billesbach, Rosvel Bracho, Abdullah F. Rahman, Herman H. Shugart

School of Earth, Environmental, & Marine Sciences Faculty Publications

Diffuse radiation can increase canopy light use efficiency (LUE). This creates the need to differentiate the effects of direct and diffuse radiation when simulating terrestrial gross primary production (GPP). Here, we present a novel GPP model, the diffuse-fraction-based two-leaf model (DTEC), which includes the leaf response to direct and diffuse radiation, and treats maximum LUE for shaded leaves (ɛmsh defined as a power function of the diffuse fraction (Df)) and sunlit leaves (ɛmsu defined as a constant) separately. An Amazonian rainforest site (KM67) was used to calibrate the model by simulating the linear relationship …

Linear And Nonlinear Effects Of Temperature And Precipitation On Ecosystem Properties In Tidal Saline Wetlands, Laura C. Feher, Michael J. Osland, Kereen T. Griffith, James B. Grace, Rebecca J. Howard, Camille L. Stagg, Nicholas M. Enwright, Ken W. Krauss, Christopher A. Gabler, Richard H. Day, Kerrylee Rogers

School of Earth, Environmental, & Marine Sciences Faculty Publications

Climate greatly influences the structure and functioning of tidal saline wetland ecosystems. However, there is a need to better quantify the effects of climatic drivers on ecosystem properties, particularly near climate-sensitive ecological transition zones. Here, we used climate- and literature-derived ecological data from tidal saline wetlands to test hypotheses regarding the influence of climatic drivers (i.e., temperature and precipitation regimes) on the following six ecosystem properties: canopy height, biomass, productivity, decomposition, soil carbon density, and soil carbon accumulation. Our analyses quantify and elucidate linear and nonlinear effects of climatic drivers. We quantified positive linear relationships between temperature and above-ground productivity …

Climate Controls Over The Net Carbon Uptake Period And Amplitude Of Net Ecosystem Production In Temperate And Boreal Ecosystems, Zheng Fu, Paul C. Stoy, Yiqi Luo, Jiquan Chen, Jian Sun, Leonardo Montagnani, Georg Wohlfahrt, Abdullah F. Rahman, Serge Rambal, Christian Bernhofer

School of Earth, Environmental, & Marine Sciences Faculty Publications

Highlights

• The start of net C uptake was determined by spring temperature in DBF and EF.

• Summer precipitation determined NEPmax anomalies in DBF and GRA.

• Climate controls annual NEP variability by regulating CUP and NEPmax.

Abstract

The seasonal and interannual variability of the terrestrial carbon cycle is regulated by the interactions of climate and ecosystem function. However, the key factors and processes determining the interannual variability of net ecosystem productivity (NEP) in different biomes are far from clear. Here, we quantified yearly anomalies of seasonal and annual NEP, net carbon uptake period (CUP), and the maximum daily NEP (NEPmax) …

Impact Of Salinity Change On Water Quality Variables From The Sediment Of An Artificial Lake Under Anaerobic Conditions, Tae-Hoon Kim, James Jihoon Kang, Sang Hyun Kim, I-Song Choi, Kwang-Hyeon Chang, Jong Min Oh, Ki-Hyun Kim

School of Earth, Environmental, & Marine Sciences Faculty Publications

Artificial reservoirs are created by dike construction in coastal areas to secure the agricultural water supply on the west coast of South Korea. These systems are found to retain brackish characteristics until total desalination is achieved. To evaluate the effects of salinity on the organic substances released from the sediment, a laboratory water-sediment column experiment was conducted to assess associated changes in water quality variables such as the sediment oxygen demand (SOD), chemical oxygen demand (COD), and concentrations of nitrogen (N) and phosphorus (P). Under high salinity conditions, the release of N from the sediment was promoted with the enhancement …

Can Ecosystem Functional Recovery Be Traced To Decomposition And Nitrogen Dynamics In Estuaries Of The Lower Laguna Madre, Texas?, Mario A. Marquez, Alejandro Fierro-Cabo, Carlos E. Cintra-Buenrostro

School of Earth, Environmental, & Marine Sciences Faculty Publications

The biggest incentive to attempt the restoration and protection of estuaries is their widely acknowledged ecological and economic importance. Assessing estuary health and recovery can most accurately come from examining ecosystem processes. The purpose of this study was to explore the potential of mass loss and nitrogen (N) dynamics during leaf litter decomposition, to detect signs of functional recovery in two estuarine systems in south Texas. Submerged litterbags with black mangrove (Avicennia germinans) leaves were retrieved at various dates over 320 days. Decomposition was about 50% slower in one of the recovering systems compared to a reference site. …

Sorption Of Cr(Iii) And Cr(Vi) To K2mn4o9 Nanomaterial A Study Of The Effect Of Ph, Time, Temperature And Interferences, J. P. Valle, B. Gonzalez, J. Schulz, D. Salinas, U. Romero, Diego F. Gonzalez, Carolina Valdes, J. M. Cantu, Thomas Eubanks, Jason Parsons

School of Earth, Environmental, & Marine Sciences Faculty Publications

A Rancieite type material (K2Mn4O9) nanomaterial was synthesized and tested for the removal of chromium (III) and chromium (VI) from aqueous solutions. The synthesized nanomaterial was characterized using powder XRD and SEM. XRD showed weak diffraction peaks at only at the angles associated with K2Mn4O9. The SEM corroborated that the nanoparticles were present; however, the nanoparticles were clustered into larger aggregates. Batch studies were performed to determine the optimum pH, capacity, time dependency, interferences, and the thermodynamics of the binding. The optimum pH for the binding of Cr(III) and Cr(VI) were determined to be pH 5 and pH 2, respectively. …

Modeling The Population Effects Of Hypoxia On Atlantic Croaker (Micropogonias Undulatus) In The Northwestern Gulf Of Mexico: Part 1—Model Description And Idealized Hypoxia, Kenneth A. Rose, Sean Creekmore, Peter Thomas, J. Kevin Craig, Md. Saydur Rahman, Rachael Miller Neilan

School of Earth, Environmental, & Marine Sciences Faculty Publications

We developed a spatially explicit, individual-based model to analyze how hypoxia effects on reproduction, growth, and mortality of Atlantic croaker in the northwestern Gulf of Mexico lead to population-level responses. The model follows the hourly growth, mortality, reproduction, and movement of individuals on a 300 × 800 spatial grid of 1-km² cells for 140 years. Chlorophyll-a concentration, water temperature, and dissolved oxygen (DO) were specified daily for each grid cell and repeated for each year of the simulation. A bioenergetics model was used to represent growth, mortality was assumed stage- and age-dependent, and the movement behavior of juveniles and …

Modeling The Population Effects Of Hypoxia On Atlantic Croaker (Micropogonias Undulatus) In The Northwestern Gulf Of Mexico: Part 2—Realistic Hypoxia And Eutrophication, Kenneth A. Rose, Sean Creekmore, Dubravko Justić, Peter Thomas, J. Kevin Craig, Rachael Miller Neilan, Lixia Wang, Md Saydur Rahman, David Kidwell

School of Earth, Environmental, & Marine Sciences Faculty Publications

Quantifying the population-level effects of hypoxia on coastal fish species has been challenging. In the companion paper (part 1), we described an individual-based population model (IBM) for Atlantic croaker in the northwestern Gulf of Mexico (NWGOM) designed to quantify the long-term population responses to low dissolved oxygen (DO) concentrations during the summer. Here in part 2, we replace the idealized hypoxia conditions with realistic DO concentrations generated from a 3-dimensional water quality model. Three years were used and randomly arranged into a time series based on the historical occurrence of mild, intermediate, and severe hypoxia year types.We also used another …

Mapping The Spatial-Temporal Variation In Ras Ghanada Seagrass Meadows And Sand Shoals Between 1996, 2006 & 2012, Ryan Brookbank

HCNSO Student Theses and Dissertations

Seagrass meadows offshore Ras Ghanada, as elsewhere, are an important component to the ecosystem providing numerous benefits to both aquatic and human life. This work focused on mapping the spatial and temporal distribution of seagrass meadows offshore Ras Ghanada using aerial photography acquired in 1996 and high-resolution satellite images captured in 2006 and 2012. The movements of sand shoals were also tracked, so as to further explain the dynamics of this ecosystem, as it is the area between the shoal crests that hosts the best developed seagrass meadows. The natural limiting factor for seagrass on the Ras Ghanada coastal shelf …

Carbon Sequestration By Australian Tidal Marshes, Peter I. Macreadie, Q. R. Oliver, J. J. Kelleway, Oscar Serrano, P. E. Carnell, C. J. Ewers Lewis, T. B. Atwood, J. Sanderman, J. Baldock, R. M. Connolly, C. M. Duarte, Paul Lavery, A. Steven, C. E, Lovelock

Research outputs 2014 to 2021

Australia’s tidal marshes have suffered significant losses but their recently recognised importance in CO2 sequestration is creating opportunities for their protection and restoration. We compiled all available data on soil organic carbon (OC) storage in Australia’s tidal marshes (323 cores). OC stocks in the surface 1 m averaged 165.41 (SE 6.96) Mg OC ha − 1 (range 14 – 963 Mg OC ha − 1). The mean OC accumulation rate was 0.55 ± 0.02 Mg OC ha − 1 yr − 1. Geomorphology was the most important predictor of OC stocks, with fluvial sites having twice the stock of OC …

Recruitment Patterns Of Juvenile Fish At An Artificial Reef Area In The Gulf Of Mexico, Rachel Noel Arney, Catheline Y. M. Froehlich, Richard Kline

School of Earth, Environmental, & Marine Sciences Faculty Publications

In 2011 the Texas Parks and Wildlife Department and the Coastal Conservation Association of Texas deployed over 4,000 concrete culverts in a designated artificial reef area off Port Mansfield, Texas, to enhance habitat for sport fish species in the Gulf of Mexico. A study was conducted to assess juvenile fish recruitment at varying culvert densities within the artificial reef area. Standard monitoring units for the recruitment of reef fish (SMURFs) were used to sample juvenile fish, and these collections were compared with visual scuba surveys. The 0.027-m3 SMURFs were placed at four different culvert densities (0, 1–50, 51–100, and 101+ …

Diversity Of Deep-Sea Fishes Of The Easter Island Ecoregion, Erin E. Easton, Javier Sellanes, Carlos F. Gaymer, Naiti A. Morales, Matthias Gorny, Eric Berkenpas

School of Earth, Environmental, & Marine Sciences Faculty Publications

The Easter Island Ecoregion is in the center of the South Pacific gyre and experiences ultra-oligotrophic conditions that could make it highly susceptible to global change and anthropogenic activities, so it is imperative that these regions are characterized and studied so that conservation and sustainable management strategies can be developed. From the few studies from the region, we know that the coastal areas are relatively depauperate and have relatively high rates of endemism. Here, we present a brief report from the first video observations from this region of the deep-dwelling fishes from ROV exploration of benthic communities from …

The Fate Of Carbon In Sediments Of The Xingu And Tapajós Clearwater Rivers, Eastern Amazon, Dailson J. Bertassoli Jr., André O. Sawakuchi, Henrique O. Sawakuchi, Fabiano N. Pupim, Gelvam A. Hartmann, Michael M. Mcglue, Cristiano M. Chiessi, Matthias Zabel, Enno Schefuß, Tatiana S. Pereira, Rudney A. Santos, Samantha B. Faustino, Paulo E. Oliveira, Denise C. Bicudo

Earth and Environmental Sciences Faculty Publications

The Xingu and Tapajós rivers in the eastern Amazon are the largest clearwater systems of the Amazon basin. Both rivers have “fluvial rias” (i.e., lake-like channels) in their downstream reaches as they are naturally impounded by the Amazon mainstem. Fluvial rias are widespread in the Amazon landscape and most of the sedimentary load from the major clearwater and blackwater rivers is deposited in these channels. So far, little is known about the role of Amazon rias as a trap and reactor for organic sediments. In this study, we used organic and inorganic geochemistry, magnetic susceptibility, diatom, and pollen analyses in …

Fish Assemblage Structure Indicates Limited Restoration Progress Over A Lustrum Of A Severely Degraded Estuary In Southern Tamaulipas, Mexico, Alejandro Fierro-Cabo, Carlos E. Cintra-Buenrostro

School of Earth, Environmental, & Marine Sciences Faculty Publications

Today the biggest incentive to attempt the restoration and protection of estuarine systems is their widely recognized ecological and economic importance. In the reconstruction of an estuary where the original aquatic communities disappeared before the restoration interventions, the fish assemblage is an adequate source of indicators of initial recovery. Following substantial restoration efforts, this study reports on the biannual for a lustrum monitoring and assessment of a severely degraded estuary (Garrapatas) in terms of its fish assemblage using a reference estuary (Barberena) in Tamaulipas, Mexico. Twenty fishes were associated with the restoring and reference estuaries. Species composition (richness, abundance, dominance) …

Impact Of The Capillary Pressure-Saturation Pore-Size Distribution Parameter On Geological Carbon Sequestration Estimates, Chu-Lin Cheng, Edmund Perfect, T. Edward Yu, Michael J. Gragg

School of Earth, Environmental, & Marine Sciences Faculty Publications

Cost estimates for geologic carbon sequestration (GCS) are vital for policy and decision makers evaluating carbon capture and storage strategies. Numerical models are often used in feasibility studies for the different stages of carbon injection and redistribution. Knowledge of the capillary pressure-saturation function for a selected storage rock unit is essential in applications used for simulating multiphase fluid flow and transport. However, the parameters describing these functions (e.g. the van Genuchten m pore size distribution parameter) are often not measured or neglected compared to other physical properties such as porosity and intrinsic permeability. In addition, the use of average …

Linear And Nonlinear Effects Of Temperature And Precipitation On Ecosystem Properties In Tidal Saline Wetlands, Laura C. Feher, Michael J. Osland, Kereen T. Griffith, James B. Grace, Rebecca J. Howard, Camille L. Stagg, Nicholas M. Enwright, Ken W. Krauss, Christopher A. Gabler, Richard H. Day, Kerrylee Rogers

School of Earth, Environmental, & Marine Sciences Faculty Publications

Climate greatly influences the structure and functioning of tidal saline wetland ecosystems. However, there is a need to better quantify the effects of climatic drivers on ecosystem properties, particularly near climate‐sensitive ecological transition zones. Here, we used climate‐ and literature‐derived ecological data from tidal saline wetlands to test hypotheses regarding the influence of climatic drivers (i.e., temperature and precipitation regimes) on the following six ecosystem properties: canopy height, biomass, productivity, decomposition, soil carbon density, and soil carbon accumulation. Our analyses quantify and elucidate linear and nonlinear effects of climatic drivers. We quantified positive linear relationships between temperature and above‐ground productivity …

Molecular And Biochemical Responses Of Hypoxia Exposure In Atlantic Croaker Collected From Hypoxic Regions In The Northern Gulf Of Mexico, Md. Saydur Rahman, Peter Thomas

School of Earth, Environmental, & Marine Sciences Faculty Publications

A major impact of global climate change has been the marked increase worldwide in the incidence of coastal hypoxia (dissolved oxygen, DOhif-α; neuronal nitric oxide synthase, nNOS; and insulin-like growth factor binding protein, igfbp mRNAs and protein carbonyl (PC, an oxidative stress indicator) content were elevated several-fold in brain and liver tissues of croaker collected from nGOM hypoxic sites. All of these molecular and biochemical biomarkers were also upregulated ~3-10-fold in croaker brain and liver tissues within 1–2 days of hypoxia exposure in controlled laboratory experiments. These results suggest that hif-αs, nNOS and igfbp-1 transcripts and PC contents …

Processes Of Multibathyal Aragonite Undersaturation In The Arctic Ocean, Jonathan G. Wynn, Lisa Robbins, L. G. Anderson

School of Geosciences Faculty and Staff Publications

During 3 years of study (2010–2012), the western Arctic Ocean was found to have unique aragonite saturation profiles with up to three distinct aragonite undersaturation zones. This complexity is produced as inflow of Atlantic‐derived and Pacific‐derived water masses mix with Arctic‐derived waters, which are further modified by physiochemical and biological processes. The shallowest aragonite undersaturation zone, from the surface to ∼30 m depth is characterized by relatively low alkalinity and other dissolved ions. Besides local influence of biological processes on aragonite undersaturation of shallow coastal waters, the nature of this zone is consistent with dilution by sea‐ice melt and invasion …

Mapping Spatial Distribution And Biomass Of Coastal Wetland Vegetation In Indonesian Papua By Combining Active And Passive Remotely Sensed Data, Aslan Aslan, Abdullah Rahman, Matthew W. Warren, Scott M. Robeson

School of Earth, Environmental, & Marine Sciences Faculty Publications

There is ongoing interest to develop remote sensing methods for mapping and monitoring the spatial distribution and biomass of mangroves. In this study, we develop a suite of methods to evaluate the combination of Landsat-8, ALOS PALSAR, and SRTM data for mapping spatial distribution of mangrove composition, canopy height, and aboveground biomass in the wide intertidal zones and coastal plains of Mimika district, Papua, Indonesia. Image segmentation followed by visual interpretation of composite PALSAR images was used to delineate mangrove areas, whereas a flexible statistical rule based classification of spectral signatures from Landsat-8 images was used to classify mangrove associations. …

Using Rare Earth Elements To Constrain Particulate Organic Carbon Flux In The East China Sea, Chin-Chang Hung, Ya-Feng Chen, Shih-Chieh Hsu, Kui Wang, Jianfang Chen, David J. Burdige

OES Faculty Publications

Fluxes of particulate organic carbon (POC) in the East China Sea (ECS) have been reported to decrease from the inner continental shelf towards the outer continental shelf. Recent research has shown that POC fluxes in the ECS may be overestimated due to active sediment resuspension. To better characterize the effect of sediment resuspension on particle fluxes in the ECS, rare earth elements (REEs) and organic carbon (OC) were used in separate two-member mixing models to evaluate trap-collected POC fluxes. The ratio of resuspended particles from sediments to total trap-collected particles in the ECS ranged from 82-94% using the OC mixing …

The Late Quaternary Rio Grande Delta—A Distinctive, Underappreciated Geologic System, Thomas E. Ewing, Juan L. Gonzalez

School of Earth, Environmental, & Marine Sciences Faculty Publications

The delta of the Rio Grande/Rio Bravo in southernmost Texas and northern Tamaulipas is one of the major deltas of North America. Over 600,000 people live on the Holocene delta and river plain, and a million more on its Pleistocene ancestors, yet geo-logic knowledge is limited. Combining available geologic information with global satellite photography gives a balanced view of an important delta. The Holocene delta begins at a point west of San Benito, Texas, forming a classic eastward-opening delta. Over half of the delta lies south of the present Rio Grande drainage. The delta passes westward into a floodplain that …

Effects Of Shoreline Dynamics On Saltmarsh Vegetation, Shailesh Sharma, Joshua Goff, Ryan M. Moody, Ashley Mcdonald, Dorothy Byron, Kenneth L. Heck Jr., Sean Powers, Carl Ferraro, Just Cebrian

University Faculty and Staff Publications

We evaluated the impact of shoreline dynamics on fringing vegetation density at mid- and low-marsh elevations at a high-energy site in the northern Gulf of Mexico. Particularly, we selected eight unprotected shoreline stretches (75 m each) at a historically eroding site and measured their inter-annual lateral movement rate using the DSAS method for three consecutive years. We observed high inter-annual variability of shoreline movement within the selected stretches. Specifically, shorelines retrograded (eroded) in year 1 and year 3, whereas, in year 2, shorelines advanced seaward. Despite shoreline advancement in year 2, an overall net erosion was recorded during the survey …

Evaluating The Influences Of Karst Hydrogeology On Freshwater Harmful Algal Blooms In Kentucky Lakes, Robert T. Schaefer

Masters Theses & Specialist Projects

A problem exists in Nolin River Lake and Rough River Lake in Kentucky, due to the increasing prevalence of cyanobacterial-based harmful algal blooms (CyanoHABs) and the threats they pose to local communities. These lakes were developed as artificial reservoirs from embankment. Further complicating the issue, the lakes are located within a heavily karstified region and there exists no plan or method currently for monitoring or managing CyanoHABs in a karst region with regard to groundwater inputs to the lake systems or their tributaries. A mixture of techniques and analysis methods was used to determine the best way to monitor and …

Assessment Of Indoor And Outdoor Pm Species At Schools And Residences In A High-Altitude Ecuadorian Urban Center, Amit U. Raysoni, Rodrigo X. Armijos, M. Margaret Weigel, Teresa Montoya, Patricia Eschanique, Marcia Racines, Wen-Whai Li

School of Earth, Environmental, & Marine Sciences Faculty Publications

An air monitoring campaign to assess children’s environmental exposures in schools and residences, both indoors and outdoors, was conducted in 2010 in three low-income neighborhoods in Z1(north), Z2(central), and Z3(southeast) zones of Quito, Ecuador - a major urban center of 2.2 million inhabitants situated 2850 meters above sea level in a narrow mountainous basin. Z1 zone, located in northern Quito, historically experienced emissions from quarries and moderate traffic. Z2 zone was influenced by heavy traffic in contrast to Z3 zone which experienced low traffic densities. Weekly averages of PM samples were collected at schools (one in each zone) and residences …