Earth Sciences Commons^™

Applications Of Environmental Dna (Edna) To Detect Subterranean And Aquatic Invasive Species: A Critical Review On The Challenges And Limitations Of Edna Metabarcoding, Sakib Tahmid Rishan, Richard Kline, Md Saydur Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

The world is struggling to solve a devastating biodiversity loss that not only affects the extinction of treasured species and irreplaceable genetic variation, but also jeopardizes the food production, health, and safety of people. All initiatives aimed to conserve biodiversity rely heavily on the monitoring of both species and populations to get accurate spatial patterns and overall population assessments. Conventional monitoring techniques, such as visual surveys and counting individuals, are problematic due to challenges in identifying cryptic species or immature life stages. Environmental DNA (eDNA) is a relatively new technology that has the potential to be a faster, non-invasive, and …

Decreased Moderate To Vigorous Physical Activity Levels In Children With Asthma Are Associated With Increased Traffic-Related Air Pollutants, Juan Aguilera, Soyoung Jeon, Amit U. Raysoni, Wen-Whai Li, Leah D. Whigham

School of Earth, Environmental, & Marine Sciences Faculty Publications

People with asthma, particularly young children, are more adversely aected by trac emissions-and regular exercise reduces asthma symptoms and improves lung function. We studied the relationship between air pollution and objectively measured physical activity in children with asthma who were attending a school near a freeway. We continuously monitored air pollutants-PM2.5, PM10, nitrogen dioxide (NO2), and ozone (O3)-at the school for 10 weeks and measured physical activity levels via accelerometry in children (n = 12, ages 6-12 years). Concentrations of PM2.5, PM10, and NO2 were negatively associated with moderate to vigorous physical activity (PM2.5 and PM10: p < .001; NO2: p = …

Oxygen And Hydrogen Isotopic Evidence That KamaʻEhuakanaloa (LōʻIhi) Seamount Hydrothermal Systems Are Recharged By Deep Pacific Seawater, Eric W. Chan, Brianna A. Alanis, Christopher R. German, Darlene S. S. Lim, John A. Breier

School of Earth, Environmental, & Marine Sciences Faculty Publications

We observed negative and positive δ18O and δ2H deviations from fluids collected at Kamaʻehuakanaloa (previously known as Lōʻihi) seamount relative to Pacific seawater from the same depth. Hydrothermal vents on the crater floor of Pele's Pit at Kamaʻehuakanaloa, at a depth of 1320 m, had δ18O and δ2H values as low as −0.19‰ and −0.3‰, respectively. Seawater collected within the caldera, within a zone 45 m above the crater floor, had δ18O and δ2H values as high as 1.15‰ and 6.5‰, respectively. In comparison, Pacific seawater at 1200 m and 1400 m at nearby station ALOHA exhibit intermediate δ18O and …

Life Cycle Assessment Of Calcium Oxide Pretreatment Of Corn Stover With Carbon Dioxide Neutralization For Ethanol Production, Jikai Zhao, Danyi Feng, Juhee Lee

School of Earth, Environmental, & Marine Sciences Faculty Publications

This work used life-cycle assessment (LCA) to determine the environmental and human health impacts of four ethanol production scenarios (S1: CaO pretreatment + H2SO4 neutralization + C6 yeast fermentation; S2: CaO pretreatment + CO2 neutralization + C6 yeast fermentation; S3: CaO pretreatment + H2SO4 neutralization + C6/C5 yeast fermentation; and S4: CaO pretreatment + CO2 neutralization + C6/C5 yeast fermentation), with the functional unit being 1 kg of 95 % ethanol. The LCA results showed that the total ozone depletion, global warming potential, smog, acidification, eutrophication, and ecotoxicity values were comparable when CO2 or H2SO4 were used to adjust the …

Post-Harvest Eucalyptus Residue Removal Reduces Soil Aggregation And Biological Activities In Central-West Brazil, Karla Nascimento Sena, Thaís Soto Boni, Kátia Luciene Maltoni, Ana Maria Rodrigues Cassiolato, Engil Isadora Pujol Pereira

School of Earth, Environmental, & Marine Sciences Faculty Publications

Tree residue removal from Eucalyptus plantations after timber harvest can reduce soil functioning by reducing the organic matter input. To assess the effects of residue management systems (RMS) on soil aggregation, carbon (C) and nitrogen (N) content, and biological activities, a field trial was conducted in a commercial Eucalyptus plantation (loamy sand soil) in Mato Grosso do Sul, Brazil. The study assessed three RMS: cut-to-length (CTL), tree-length (TL), and bare litter (BL), respectively. After 21 months, undisturbed soil samples were collected and physically isolated into three aggregate-size fractions: large macroaggregates (LM), medium macroaggregates (SM), and microaggregates (MI). Results showed that …

Significance Of Storage Conditions On The Flow Properties Of Wheat Flours, Jared Lou Rivera, Jikai Zhao, Aminu Owonikoko, Kaliramesh Siliveru

School of Earth, Environmental, & Marine Sciences Faculty Publications

Flow properties of wheat flours are influenced by their intrinsic properties and environmental conditions during handling. This study evaluated the effects of environmental conditions (temperature and relative humidity- %RH) and flour properties (particle size and wheat class) on the flow properties of wheat flours. Size fractions from hard red winter (HRW) and soft red winter (SRW) wheat were produced through sieving. Flour fractions were then exposed to various temperature (25 and 35 oC) and relative humidity (50, 60, and 70%RH) combinations (t = 3 h) to evaluate the effects of environmental conditions. Flow indicators (Hausner ratio – HR and compressibility …

Rapidly Changing Range Limits In A Warming World: Critical Data Limitations And Knowledge Gaps For Advancing Understanding Of Mangrove Range Dynamics In The Southeastern Usa, Rémi Bardou, Michael J. Osland, Steven Scyphers, Christine Shepard, Karen E. Aerni, Jahson B. Alemu I, Robert Crimian, Richard H. Day, Nicholas M. Enwright, Christopher A. Gabler

School of Earth, Environmental, & Marine Sciences Faculty Publications

Climate change is altering species’ range limits and transforming ecosystems. For example, warming temperatures are leading to the range expansion of tropical, cold-sensitive species at the expense of their cold-tolerant counterparts. In some temperate and subtropical coastal wetlands, warming winters are enabling mangrove forest encroachment into salt marsh, which is a major regime shift that has significant ecological and societal ramifications. Here, we synthesized existing data and expert knowledge to assess the distribution of mangroves near rapidly changing range limits in the southeastern USA. We used expert elicitation to identify data limitations and highlight knowledge gaps for advancing understanding of …

Flow Monitoring And Tidal Exchange Ratio Estimation For The Bahia Grande After Widening Of The Carl Joe Gayman Pilot Channel: Bahia Grande, Cameron County, Tx, Sabas Lopez Iii

Theses and Dissertations

The Bahia Grande (BG) is an 8,500-acre set of coastal bays and wetlands located between Brownsville and Port Isabel, Tx, near the Gulf of Mexico (GOM) coastline. In 2005, the Carl Joe Gayman Pilot Channel was constructed to address hypersalinity concerns that resulted from natural and anthropogenically-caused tidal isolation since the early 1940’s. In 2022, the Texas General Land Office (GLO) increased the channel’s width and depth in anticipation of increasing tidal exchange ratios by a factor of two to three. Once the channel widening was complete, two SL-1500-3G side-looking acoustic doppler current profilers (ADCPs) were periodically deployed beneath the …

Long-Term Spatial And Temporal Assessment Of Criteria Air Pollutants Concentration Trends In The Lower Rio Grande Valley Region Of Texas, Usa, Md Salahuddin Majumder

Theses and Dissertations

Air pollution is a substantial environmental challenge all over the world. This study investigated the long-term air pollution levels in the Lower Rio Grande Valley region, by utilizing data collected from five continuous ambient monitoring stations in two counties over 23 years, from January 2000 to December 2022, to analyze daily, monthly, and seasonal variations of different pollutants, including ground-level ozone, particulate matter, and carbon monoxide. This study also identified distinct daily and seasonal patterns for O3, PM2.5, PM10, and CO at each monitoring site, influenced by factors such as traffic emissions, temperature, solar radiation, indoor heating, and weather conditions. …

Predictive Ecology And Management Of Phyllosphere Microbial Communities Through Cross-Scale Synthesis, David W. Armitage, Morgan E. Carter, Robin A. Choudhury, Mitja Remus-Emsermann, Cindy E. Morris, Johan H. Leveau, Linda L. Kinkel, José Pablo Dundore-Arias

School of Earth, Environmental, & Marine Sciences Faculty Publications

Here we summarize the main takeaways from a symposium and hybrid virtual and in-person participatory discussion focused on the challenges of scale in understanding the ecology and management of phyllosphere microbial communities. We provide an overview of the confounding effects of spatial scale on inference in microbial ecology, the spatial organization of microbial interactions in the phyllosphere, advances and remaining gaps in measuring phyllosphere colonization across scales, and the epidemiology in the phyllosphere. We hope to motivate further discussion and the development and adoption of creative approaches to solving the challenges of scale to enhance fundamental understanding and practical management …

Detection Of A Diverse Endophyte Assemblage Within Fungal Communities Associated With The Arundo Leaf Miner, Lasioptera Donacis (Diptera: Cecidomyiidae), Marie-Claude Bon, John A. Goolsby, Guy Mercadier, Fatiha Guermache, Javid Kashef, Massimo Cristofaro, Ann T. Vacek, Alan Kirk

School of Earth, Environmental, & Marine Sciences Faculty Publications

The larvae of Lasioptera donacis Coutin feed on fungal communities lining galleries within the mesophyll of leaf sheaths of Arundo donax in an aggregative manner. It has been stated that L. donacis could have established a fundamental symbiotic relationship with one fungus, although the fungal composition of these communities remains unsettled. Using a culture-dependent approach and ITS sequencing, the present work characterizes and compares the fungal communities associated with L. donacis in Eurasia with the endophytes of A. donax in Texas where L. donacis is absent. The 65 cultivable isolates obtained from L. donacis fungal communities were sorted into 15 …

Biodiversity Of Forage Fishes In The Lower Laguna Madre, Southernmost Texas, David Camarillo Jr., Elizabeth Mogus Garcia, Carlos E. Cintra-Buenrostro

School of Earth, Environmental, & Marine Sciences Faculty Publications

Coastal estuarine ecosystems serve as nursery habitats for many commercially and recreationally important fishes. Biodiversity is a structural indicator and has been used as a metric for conservation and management. In the hypersaline Lower Laguna Madre of Texas, a variety of organisms makes their living in and around the dominant seagrass vegetation. This study provides a general assessment of forage fishes biodiversity collected seasonally with bag seines in two sites: Holly Beach (HB) and South Bay (SB) within the most southern Texas bay system as part of a broader study on fish biology. A total of 15,880 fishes representing 32 …

Characterizing The Response Of The Coastal Rio Grande To Upstream Damming, Timothy A. Goudge, John M. Swartz, Tian Y. Dong, David Mohrig

School of Earth, Environmental, & Marine Sciences Faculty Publications

Dams are major obstructions to the flow of water and the transport of sediment in rivers. Much work has shown the construction of dams, and storage of sediment in reservoirs, can lead to significant changes in the morphodynamic behavior of alluvial rivers; however, in most cases, the effect of damming has a finite downstream limit as sediment is supplied back to the river through channel bed/bank erosion and/or tributary inputs. Here we present a study of a natural experiment that isolates one source of sediment downstream of a dam – the lower Rio Grande, which has no major tributary inputs …

Air Pollution In South Texas: A Short Communication Of Health Risks And Implications, Sai Deepak Pinakana, Esmeralda Mendez, Ismaila Ibrahim, Md. Salahuddin Majumder, Amit U. Raysoni

School of Earth, Environmental, & Marine Sciences Faculty Publications

Air pollution is a major public health concern. The region of South Texas in the United States has experienced high levels of air pollution in recent years due to an increase in population, cross-border trade between the U.S.A. and Mexico, and high vehicular activity. This review assesses the relationships between human health and air pollution in South Texas. A thorough scientific search was performed using PubMed, Science Direct, and ProQuest, with most of the literature focusing on the source apportionment of particulate matter that is 2.5 microns or less in width (PM2.5), Carbon Dioxide (CO2), carbon monoxide (CO), Black Carbon …

Assessment Of Air Pollution Levels During Sugarcane Stubble Burning Event In La Feria, South Texas, Usa, Sai Deepak Pinakana, Edward Robles, Esmeralda Mendez, Amit U. Raysoni

School of Earth, Environmental, & Marine Sciences Faculty Publications

Agricultural stubble burning is the third largest source of air pollution after vehicular and industrial emissions. Fine particulate matter (PM2.5), volatile organic compounds (VOCs), carbon monoxide (CO), nitrogen dioxide (NO2), and black carbon (BC) are some of the pollutants emitted during such burning events. The Lower Rio Grande Valley (RGV) region of South Texas is a major hub of agricultural activity, and sugarcane farming is one of them. Unfortunately, this activity results in episodic events of high air pollution in this low-resourced, Hispanic/Latino majority region of the U.S.–Mexico border. This study presents results from a sugarcane site in La Feria, …

Health And Safety Effects Of Airborne Soil Dust In The Americas And Beyond, Daniel Q. Tong, Thomas E. Gill, William A. Sprigg, Robert Scott Van Pelt, Alexander Baklanov, Bridget Marie Barker, Jesse E. Bell, Juan Castillo, Santiago Gassó, Cassandra Gaston, Amit U. Raysoni

School of Earth, Environmental, & Marine Sciences Faculty Publications

Risks associated with dust hazards are often underappreciated, a gap between the knowledge pool and public awareness that can be costly for impacted communities. This study reviews the emission sources and chemical, physical, and biological characteristics of airborne soil particles (dust) and their effects on human and environmental health and safety in the Pan-American region. American dust originates from both local sources (western United States, northern Mexico, Peru, Bolivia, Chile, and Argentina) and long-range transport from Africa and Asia. Dust properties, as well as the trends and interactions with criteria air pollutants, are summarized. Human exposure to dust is associated …

Port-Of-Entry Simulation Model For Potential Wait Time Reduction And Air Quality Improvement: A Case Study At The Gateway International Bridge In Brownsville, Texas, Usa, Benjamin Stewart, Hiram Moya, Amit U. Raysoni, Esmeralda Mendez, Matthew Vechione

School of Earth, Environmental, & Marine Sciences Faculty Publications

The mathematical study known as queueing theory has recently become a major point of interest for many government agencies and private companies for increasing efficiency. One such application is vehicle queueing at an international port-of-entry (POE). When queueing, fumes from idling vehicles negatively affect the overall health and well-being of the community, especially the U.S. Customs and Border Protection (CBP) agents that work at the POEs. As such, there is a need to analyze and optimize the border crossing queuing operations to minimize wait times and number of vehicles in the queue and, thus, reduce the vehicle emissions. For this …

A Review Of Literature On The Usage Of Low-Cost Sensors To Measure Particulate Matter, Amit U. Raysoni, Sai Deepak Pinakana, Esmeralda Mendez, Dawid K. Wladyka, Katarzyna Sepielak, Owen Temby

School of Earth, Environmental, & Marine Sciences Faculty Publications

With advances in technological sciences, individuals can utilize low-cost air monitoring sensors to record air quality at homes, schools, and businesses. Air quality data collected from LCSs are publicly accessible, informing the community of the air quality around them. It is important to measure local and regional particulate matter (PM) concentrations to keep the public involved, especially those with specific health concerns, such as asthma, wheezing, and seasonal allergies. The number of studies involving the use of LCSs to evaluate PM levels is increasing with more manufacturers producing ‘easy to use’ LCSs targeting the public. The goal of this review …

Isomerization Of Galactose To Tagatose: Recent Advances In Non-Enzymatic Isomerization, Jikai Zhao, Zhuo Wang, Qing Jin, Danyi Feng, Juhee Lee

School of Earth, Environmental, & Marine Sciences Faculty Publications

The valorization of galactose derived from acid whey to low-calorie tagatose has gained increasing attention. Enzymatic isomerization is of great interest but faces several challenges, such as poor thermal stability of enzymes and a long processing time. In this work, non-enzymatic (supercritical fluids, triethylamine, arginine, boronate affinity, hydrotalcite, Sn-β zeolite, and calcium hydroxide) pathways for galactose to tagatose isomerization were critically discussed. Unfortunately, most of these chemicals showed poor tagatose yields (70%). The latter is able to form a tagatose–calcium hydroxide–water complex, which stimulates the equilibrium toward tagatose and prevents sugar degradation. Nevertheless, the excessive use of calcium hydroxide may …

Quantification Of Hydraulic Trait Control On Plant Hydrodynamics And Risk Of Hydraulic Failure Within A Demographic Structured Vegetation Model In A Tropical Forest (Fates–Hydro V1.0), Chonggang Xu, Bradley O. Christoffersen, Zachary Robbins, Ryan G. Knox, Rosie A. Fisher, Rutuja Chitra-Tarak, Martijn Slot, Kurt C. Solander, Lara M. Kueppers, Charles D. Koven, Nate G. Mcdowell

School of Integrative Biological & Chemical Sciences Faculty Publications

Vegetation plays a key role in the global carbon cycle and thus is an important component within Earth system models (ESMs) that project future climate. Many ESMs are adopting methods to resolve plant size and ecosystem disturbance history, using vegetation demographic models. These models make it feasible to conduct more realistic simulation of processes that control vegetation dynamics. Meanwhile, increasing understanding of the processes governing plant water use, and ecosystem responses to drought in particular, has led to the adoption of dynamic plant water transport (i.e., hydrodynamic) schemes within ESMs. However, the extent to which variations in plant hydraulic traits …

Are Avocados Toast? A Framework To Analyze Decision-Making For Emerging Epidemics, Applied To Laurel Wilt, Berea A. Etherton, Robin A. Choudhury, R. I. Alcalá-Briseño, Y. Xing, A. I. Plex Sulá, D. Carrillo, J. Wasielewski, L. L. Stelinski, K. A. Grogan, F. Ballen

School of Earth, Environmental, & Marine Sciences Faculty Publications

CONTEXT

When emerging pathogens threaten global food security, collective actionfor disease management is key for protecting food systems. We evaluate how the informal exchange of information about epidemic and economic outcomes can influence the management decisions of individuals and the resulting epidemics, in the context of the avocado laurel wilt epidemic in south Florida.

OBJECTIVES

In scenario analyses, we addressed how socioeconomic networks, laurel wilt epidemic networks, policy incentive structures, and social behaviors combine to influence (a) information exchange across this region, (b) growers' decisions about disease management, and (c) epidemic spread and yield loss. We identified the scenarios …

Increased Floodplain Inundation In The Amazon Since 1980, Ayan Fleischmann, Fabrice Papa, Stephen K. Hamilton, Alice Fassoni-Andrade, Sly Wongchuig, Jhan Carlo Espinoza, Rodrigo Paiva, John Melack, Etienne Fluet-Chouinard, Rafael M. Almeida

School of Earth, Environmental, & Marine Sciences Faculty Publications

Extensive floodplains throughout the Amazon basin support important ecosystem services and influence global water and carbon cycles. A recent change in the hydroclimatic regime of the region, with increased rainfall in the northern portions of the basin, has produced record-breaking high water levels on the Amazon River mainstem. Yet, the implications for the magnitude and duration of floodplain inundation across the basin remain unknown. Here we leverage state-of-the-art hydrological models, supported by in situ and remote sensing observations, to show that the maximum annual inundation extent along the central Amazon increased by 26% since 1980. We further reveal increased flood …

On The Architecture Of Collaboration In Inter-Organizational Natural Resource Management Networks, Gordon M. Hickey, Evelyn Roozee, Remko Voogd, Jasper R. De Vries, Antonia Sohns, Dongkyu Kim, Owen Temby

School of Earth, Environmental, & Marine Sciences Faculty Publications

This paper reviews the architecture of collaboration that exists within inter-organizational natural resource management (NRM) networks. It presents an integrative conceptual framework designed to help operationalize the multi-level interactions that occur between different dimensions of trust, risk perception, and control as key concepts in inter-organizational collaboration. The objective is to identify and justify a series of propositions considered suitable for assessing inter-organizational NRM network collaboration through empirical work. Such an integrative conceptualization goes beyond the existing trust scholarship related to collaborative NRM, and, we argue, offers a useful starting point for further exploring some of the ‘inner’ social dynamics affecting …

Cascading Effects Of Cover Crops On The Subsequent Cash Crop Defense Against The Polyphagous Herbivore Fall Armyworm (Spodoptera Frugiperda), Adegboyega Fajemisin, Alexis Racelis, Rupesh R. Kariyat

School of Earth, Environmental, & Marine Sciences Faculty Publications

Simple Summary

Although studies have started to show that the effects of cover crops can translate into the cash cropping season, there is little information on the cascading effects of cover crops on the subsequent cash crop defenses, especially against polyphagous herbivores. To bridge this information gap, we conducted a field and laboratory study to investigate the cascading effects of different cover crop species on the subsequent cash crop defense against the polyphagous herbivore fall armyworm (Spodoptera frugiperda) across three fields in the Lower Rio Grande Valley in south Texas. Our field and laboratory results revealed that cover crop treatments …

A Critical Review On Water Overconsumption In Lignocellulosic Biomass Pretreatment For Ethanol Production Through Enzymic Hydrolysis And Fermentation, Jikai Zhao, Juhee Lee, Donghai Wang

School of Earth, Environmental, & Marine Sciences Faculty Publications

Global demand for renewable and sustainable energy fostered the considerable development of biomass-to-ethanol valorization strategies. Thermochemical pretreatment methods have been proposed to render biomass more amenable to enzymatic and microbial digestion. However, the efforts have not led to its industrial-scale worldwide realization. One of the obstacles to commercialization could be related to water overconsumption, as excessive water washing of the pretreated slurry is often performed to remove inhibitory compounds and residual chemicals after biomass pretreatment. Only increasing solid loading for biomass pretreatment results in ineffective pretreatment performance, more inhibitors formation, and high viscosity, which in turn necessitates the water washing …

Metal Contents In House Geckos (Squamata: Gekkonidae) From Industrial And Urban Areas Of Southern Tamaulipas, Mexico And Western Andalucía, Spain, May Reflect Airborne Metal Pollution, Luisiana Morales-Zamudio, Alejandro Fierro-Cabo, Md. Saydur Rahman, Miguel Antonio Dominguez-Crespo

School of Earth, Environmental, & Marine Sciences Faculty Publications

House geckos share living quarters with humans in the tropical and subtropical regions inhabited by these reptiles. Gecko behavior, biological traits, continuous exposure to suspended particulate matter 0 µm in diameter (PM10) and dust, as well as status as exotic species, motivated the choice of these species to examine environmental exposure to ambient air pollutants, in particular metals, and subsequent accumulation in these organisms. One part of the study was conducted in Tamaulipas (Mexico) where Hemydactylus frenatus is abundant in urban and industrial environments, the other part was conducted in Andalucia (Spain) where Tarentola mauritanica is found in similar environments. …

Impacts Of Tectonic Subsidence On Basin Depth And Delta Lobe Building, Tian Y. Dong, Jeffrey A. Nittrouer, Brandee Carlson, Brandon Mcelroy, Elena Il’Icheva, Maksim Pavlov, Hongbo Ma

School of Earth, Environmental, & Marine Sciences Faculty Publications

Channel avulsions on river deltas are the primary means to distribute sediment and build land at the coastline. Many studies have detailed how avulsions generate delta lobes, whereby multiple lobes amalgamate to form a fan-shaped deposit. These studies often assume steady subsidence and uniform basin depth. In nature, however, lobe building is disrupted by variable subsidence, and progradation of lobes into basins with variable depth: conditions that are prevalent for tectonically active areas. Herein, we explore sediment dispersal and deposition patterns across scales using measurements of delta and basin morphology compiled from field surveys and remote sensing, collected over 150 …

Inter-Seasonal Comparison Of Acoustic Propagation In A Thalassia Testudinum Seagrass Meadow In A Shallow Sub-Tropical Lagoon, Kevin M. Lee, Megan S. Ballard, Andrew R. Mcneese, Preston S. Wilson, Gabriel R. Venegas, Mathew C. Zeh, Abdullah Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

Acoustic propagation measurements were collected in a seagrass meadow in a shallow lagoon for periods of over 65 h in winter and 93 h in summer. A bottom-deployed sound source transmitted chirps (0.1–100 kHz) every 10 min that were received on a four-receiver horizontal hydrophone array. Oceanographic probes measured various environmental parameters. Daytime broadband acoustic attenuation was 2.4 dB greater in summer than winter, and the median received acoustic energy levels were 8.4 dB lower in summer compared to winter. These differences were attributed in part to seasonal changes in photosynthesis bubble production and above-ground seagrass biomass.

Inter-Seasonal Comparison Of Acoustic Propagation In A Thalassia Testudinum Seagrass Meadow In A Shallow Sub-Tropical Lagoon, Kevin M. Lee, Megan S. Ballard, Andrew R. Mcneese, Preston S. Wilson, Gabriel R. Venegas, Mathew C. Zeh, Abdullah Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

Acoustic propagation measurements were collected in a seagrass meadow in a shallow lagoon for periods of over 65 h in winter and 93 h in summer. A bottom-deployed sound source transmitted chirps (0.1–100 kHz) every 10 min that were received on a four-receiver horizontal hydrophone array. Oceanographic probes measured various environmental parameters. Daytime broadband acoustic attenuation was 2.4 dB greater in summer than winter, and the median received acoustic energy levels were 8.4 dB lower in summer compared to winter. These differences were attributed in part to seasonal changes in photosynthesis bubble production and above-ground seagrass biomass.

Balancing Renewable Energy And River Resources By Moving From Individual Assessments Of Hydropower Projects To Energy System Planning, Jeffrey J. Opperman, Juan Pablo Carvallo, Rafael Kelman, Rafael J. P. Schmitt, Rafael M. Almeida, Emily Chapin, Alexander Flecker, Marc Goichot, Guenther Guenther Grill, Julien J. Harou

School of Earth, Environmental, & Marine Sciences Faculty Publications

As governments and non-state actors strive to minimize global warming, a primary strategy is the decarbonization of power systems which will require a massive increase in renewable electricity generation. Leading energy agencies forecast a doubling of global hydropower capacity as part of that necessary expansion of renewables. While hydropower provides generally low-carbon generation and can integrate variable renewables, such as wind and solar, into electrical grids, hydropower dams are one of the primary reasons that only one-third of the world’s major rivers remain free-flowing. This loss of free-flowing rivers has contributed to dramatic declines of migratory fish and sediment delivery …