Physical Sciences and Mathematics Commons^™

Timing Of Favorable Conditions, Competition And Fertility Interact To Govern Recruitment Of Invasive Chinese Tallow Tree In Stressful Environments, Christopher A. Gabler, Evan Siemann

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The rate of new exotic recruitment following removal of adult invaders (reinvasion pressure) influences restoration outcomes and costs but is highly variable and poorly understood. We hypothesize that broad variation in average reinvasion pressure of Triadica sebifera (Chinese tallow tree, a major invader) arises from differences among habitats in spatiotemporal availability of realized recruitment windows. These windows are periods of variable duration long enough to permit establishment given local environmental conditions. We tested this hypothesis via a greenhouse mesocosm experiment that quantified how the duration of favorable moisture conditions prior to flood or drought stress (window duration), competition and nutrient …

A Lover And A Fighter: The Genome Sequence Of An Entomopathogenic Nematode Heterorhabditis Bacteriophora, Xiaodong Bai, Byron J. Adams, Todd A. Ciche, Sandra Clifton, Randy Gaugler, Kwi-Suk Kim, Parwinder Grewal

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Heterorhabditis bacteriophora are entomopathogenic nematodes that have evolved a mutualism with Photorhabdus luminescens bacteria to function as highly virulent insect pathogens. The nematode provides a safe harbor for intestinal symbionts in soil and delivers the symbiotic bacteria into the insect blood. The symbiont provides virulence and toxins, metabolites essential for nematode reproduction, and antibiotic preservation of the insect cadaver. Approximately half of the 21,250 putative protein coding genes identified in the 77 Mbp high quality draft H. bacteriophora genome sequence were novel proteins of unknown function lacking homologs in Caenorhabditis elegans or any other sequenced organisms. Similarly, 317 of the …

Uso De Hábitat Y Perspectivas De Lontra Longicaudis En Un Área Protegida De Tamaulipas, México, Piedad Esther Mayagoitia-González, Alejandro Fierro-Cabo, Raul Valdez, Mark Andersen, David Cowley, Robert Steiner

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

El hábitat de la nutria neotropical (Lontra longicaudis) en el Área Natural Protegida (ANP) La Vega Escondida, ubicada al sur de Tamaulipas, se encuentra rodeado de un paisaje urbano en expansión. Los humedales en esta región están sometidos a una intensa presión debido a diversas actividades antropogénicas tales como la agricultura, ganadería y pesca comercial, así como construcciones y rellenos en orillas de laguna y río. El presente estudio tuvo como objetivos principales la evaluación y uso de hábitat de la nutria dentro del ANP La Vega Escondida, así como determinar la actitud de la población humana hacia esta especie. …

Air Pollution And Acute Respiratory Response In A Panel Of Asthmatic Children Along The U.S.–Mexico Border, Stefanie E. Sarnat, Amit U. Raysoni, Wen-Whai Li, Fernando Holguin, Brent A. Johnson, Silvia Flores Luevano, Jose Humberto Garcia, Jeremy A. Sarnat

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Background: Concerns regarding the health impact of urban air pollution on asthmatic children are pronounced along the U.S.–Mexico border because of rapid population growth near busy border highways and roads.

Objectives: We conducted the first binational study of the impacts of air pollution on asthmatic children in Ciudad Juarez, Mexico, and El Paso, Texas, USA, and compared different exposure metrics to assess acute respiratory response.

Methods: We recruited 58 asthmatic children from two schools in Ciudad Juarez and two schools in El Paso. A marker of airway inflammation [exhaled nitric oxide (eNO)], respiratory symptom surveys, and pollutant measurements (indoor and …

Processing Quality Of Potato Tubers Produced During Autumn And Spring And Stored At Different Temperatures, Sergio T. De Freitas, Engil Isadora Pujol Pereira, Ana Cecilia S. Gomez, Auri Brackmann, Fernando Nicoloso, Dilson A. Bisognin

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The objective of this work was to access processing quality of potato clones (Solanum tuberosum) Asterix, SMINIA793101-3, and Missaukee cultivated during spring and autumn growing seasons and stored at 4, 8, 12, or 25ºC. Clones grown in spring had shorter dormancy than clones grown in autumn. Potato tubers grown in spring and autumn and stored at 4ºC, as well as tubers grown in autumn and stored at 8ºC had no sprouting for six months. Among clones grown in autumn, the longest dormancy period during storage at 12ºC was observed in the clone SMINIA793101-3, and at 25ºC was in the clone …

Selective Capture Of Transcribed Sequences: A Promising Approach For Investigating Bacterium-Insect Interactions, Ruisheng An, Parwinder Grewal

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Bacterial interactions with eukaryotic hosts are complex processes which vary from pathogenic to mutualistic. Identification of bacterial genes differentially expressed in the host, promises to unravel molecular mechanisms driving and maintaining such interactions. Several techniques have been developed in the past 20 years to investigate bacterial gene expression within their hosts. The most commonly used techniques include in-vivo expression technology, signature-tagged mutagenesis, differential fluorescence induction, and cDNA microarrays. However, the limitations of these techniques in analyzing bacterial in-vivo gene expression indicate the need to develop alternative tools. With many advantages over the other methods for analyzing bacterial in-vivo gene expression, …

Would Predatory Drillhole Frequency On Chione Spp. Increase Under The Suggested Climate Change Scenario? Comparing Pleistocene And Modern Rhodolith Beds, Carlos E. Cintra-Buenrostro

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The analysis of predatory drillholes allow paleontologists to reconstruct trophic relationships of ancient systems. To evaluate the potential effects of climate and sea level change on predation frequency by gastropods on bivalves, species of the genus Chione from the Gulf of California were selected because they are a commercially exploited resource - at least locally - and abundant in both modern and Pleistocene (sea level high stand of oxygen substage 5e) samples from rhodolith beds. The present study focused to answer a practical question: would predation on Chione spp. increase under the suggested climate - warming - change scenario? A …

Would Predatory Drillhole Frequency On Chione Spp. Increase Under The Suggested Climate Change Scenario? Comparing Pleistocene And Modern Rhodolith Beds, Carlos E. Cintra-Buenrostro

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The analysis of predatory drillholes allow paleontologists to reconstruct trophic relationships of ancient systems. To evaluate the potential effects of climate and sea level change on predation frequency by gastropods on bivalves, species of the genus Chione from the Gulf of California were selected because they are a commercially exploited resource - at least locally - and abundant in both modern and Pleistocene (sea level high stand of oxygen substage 5e) samples from rhodolith beds. The present study focused to answer a practical question: would predation on Chione spp. increase under the suggested climate - warming - change scenario? A …

Differences In Immune Defense Evasion Of Selected Inbred Lines Of Heterorhabditis Bacteriophora In Two White Grub Species, Ruisheng An, Marcio Voss, Ganpati B. Jagdale, Parwinder Grewal

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

We determined virulence of seven Heterorhabditis bacteriophora strain GPS11 inbred lines possessing superior infective juvenile longevity, and heat and ultra violet radiation tolerance against white grubs Popillia japonica and Cyclocephala borealis. At 1 and 2 weeks after treatment, inbred line A2 was significantly more virulent towards P. japonica compared to the parent strain GPS11 and inbred lines A7, A8, A12 and A21; and line A2 caused significantly higher C. borealis mortality than lines A6 and A12. Penetration, encapsulation and survival of two inbred lines, A2 and A12, that showed the highest and lowest virulence against both grub species were then …

A Comprehensive Method For Fractionating Soil Organic Matter Not Protected And Protected From Decomposition By Physical And Chemical Mechanisms, César Plaza, José M. Fernández, Engil Isadora Pujol Pereira, Alfredo Polo

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The objective of this work was to describe a method for isolating meaningful and measurable soil organic matter (SOM) pools that differ in the mechanisms by which they are protected from decomposition. The proposed method is appropriate for soil C stabilization and sequestration studies. Unlike previous fractionation schemes, this procedure allows free SOM located between aggregates (unprotected C pool) and SOM occluded within both macroaggregates and microaggregates (C weakly and strongly protected by physical mechanisms, respectively) to be recovered separately, freed from the soil mineral matrix and the mineral-associated SOM pool (C pool protected by chemical mechanisms) and thus well …

Soil Nitrogen Transformations Under Elevated Atmospheric Co2 And O3 During The Soybean Growing Season, Engil Isadora Pujol Pereira, Haegeun Chung, Kate Scow, Michael J. Sadowsky, Chris Van Kessel

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

We investigated the influence of elevated CO2 and O3 on soil N cycling within the soybean growing season and across soil environments (i.e., rhizosphere and bulk soil) at the Soybean Free Air Concentration Enrichment (SoyFACE) experiment in Illinois, USA. Elevated O3 decreased soil mineral N likely through a reduction in plant material input and increased denitrification, which was evidenced by the greater abundance of the denitrifier gene nosZ. Elevated CO2 did not alter the parameters evaluated and both elevated CO2 and O3 showed no interactive effects on nitrifier and denitrifier abundance, nor on total and mineral N concentrations. These results …

Molecular Mechanisms Of Persistence Of Mutualistic Bacteria Photorhabdus In The Entomopathogenic Nematode Host, Ruisheng An, Parwinder Grewal

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Symbioses between microbes and animals are ubiquitous, yet little is known about the intricate mechanisms maintaining such associations. In an emerging mutualistic model system, insect-pathogenic bacteria Photorhabdus and their insect-parasitic nematode partner Heterorhabditis, we found that the bacteria undergo major transcriptional reshaping in the nematode intestine. Besides general starvation mechanisms, the bacteria induce cellular acidification to slow down growth, switch to pentose phosphate pathway to overcome oxidative stress and nutrition limitation, and shed motility but develop biofilm to persist in the nematode intestine until being released into the insect hemolymph. These findings demonstrate how the symbiotic bacteria reduce their …

Health Impacts Of Traffic Related Air Pollution, Amit U. Raysoni, Wen-Wahi Li

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Ambient air pollution can be a serious cause of concern for any community. Anthropogenic ambient air pollutants can emanate from industries, traffic, geological sources and domestic heating and cooking. However, studies have shown that traffic related air pollution can have far more detrimental health effects than non-combustion sources. These adverse health effects are most profound in sensitive populations like the elderly and young children. The World Health Organization (WHO) attributes more than 300 million deaths every year to ambient air pollution. The WHO’s Air Quality Guidelines (AQG) and the United States Environment Protection Agency’s (USEPA) National Ambient Air Quality Standards …

Indicadores Funcionales Y Estructurales Para Evaluar El Estado De Conservación De Humedales Costeros En El Sur De Tamaulipas, Alejandro Fierro-Cabo

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

El manejo adecuado de las zonas costeras requiere de herramientas que permitan detectar procesos degradantes en los ecosistemas estratégicos prestadores de servicios ambientales. Los indicadores ecológicos responden adecuadamente a esta necesidad en humedales costeros. Se estudiaron ocho humedales de origen y características distintas, con afectaciones contrastantes conocidas. Se seleccionaron los indicadores que mejor discriminaron los sitios y se utilizaron para evaluar la evolución del estado de conservación de los mismos. La correspondencia ecológica entre indicadores funcionales y estructurales no se confirmó en todos los casos, por lo que es necesario utilizar ambos tipos para obtener un mejor diagnóstico. En dicha …

Optimization And Validation Of An Enzymatic Method To Quantify Glucose In Potato Tubers, Engil Isadora Pujol Pereira, Tatiana Emanuelli, Dilson Antonio Bisognin, Sergio T. De Freitas

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The processing industry requires potato tubers with low levels of reduced sugars, glucose and fructose, which is responsible for the whiteness of the chip color. The objective of this research was to optimize and validate a simple, inexpensive, and precise enzymatic method to quantify glucose in potato tubers. This method will be useful in breeding programs to select clones for processing purposes with low levels of glucose. The validation procedure followed the recommendations described in INMETRO document DOQ-CGCRE-008 in 2003. The method was linear between 1.25 to 40µg of glucose in the sample. The quantification limit was 0.319mg g-1 of …

Rapid Evolution In Introduced Species, ‘Invasive Traits’ And Recipient Communities: Challenges For Predicting Invasive Potential, Kenneth D. Whitney, Christopher A. Gabler

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The damaging effects of invasive organisms have triggered the development of Invasive Species Predictive Schemes (ISPS). These schemes evaluate biological and historical characteristics of species and prioritize those that should be the focus of exclusion, quarantine, and/or control. However, it is not clear how commonly these schemes take microevolutionary considerations into account. We review the recent literature and find that rapid evolutionary changes are common during invasions. These evolutionary changes include rapid adaptation of invaders to new environments, effects of hybridization, and evolution in recipient communities. Strikingly, we document 38 species in which the specific traits commonly associated with invasive …

Physiological Aging Of Potato Tubers Produced During Fall And Spring Growing Seasons And Stored Under Different Temperatures, Dilson A. Bisognin, Sergio T. De Freitas, Auri Brackmann, Jeronimo Luiz Andriolo, Engil Isadora Pujol Pereira, Douglas Renator Muller, Mauricio Guerra Bandinelli

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Adequate tuber storage is necessary to maintain a good availability of potato tubers in the market and to get seeds with adequate physiological age at planting. The objective of this work was to determine the effect of different storage temperatures on tuber physiological aging of three potato clones produced during fall and spring growing seasons. The experiment was carried out as factorial of three clones (Asterix, SMIJ461-1 and SMINIA793101-3) by four storage temperatures (4, 8, 12 and 25 ºC) and two growing seasons (fall and spring) in a random design with four replications. At 30-day intervals, tubers were evaluated from …

Rapid Evolution In Introduced Species, ‘Invasive Traits’ And Recipient Communities: Challenges For Predicting Invasive Potential, Kenneth D. Whitney, Christopher A. Gabler

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The damaging effects of invasive organisms have triggered the development of Invasive Species Predictive Schemes (ISPS). These schemes evaluate biological and historical characteristics of species and prioritize those that should be the focus of exclusion, quarantine, and/or control. However, it is not clear how commonly these schemes take microevolutionary considerations into account. We review the recent literature and find that rapid evolutionary changes are common during invasions. These evolutionary changes include rapid adaptation of invaders to new environments, effects of hybridization, and evolution in recipient communities. Strikingly, we document 38 species in which the specific traits commonly associated with invasive …

Trampling, Peeling And Nibbling Mussels: An Experimental Assessment Of Mechanical And Predatory Damage To Shells Of Mytilus Trossulus (Mollusca: Mytilidae), Carlos E. Cintra-Buenrostro

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Shell damage, if properly recognized, can provide information about biotic interactions between molluscs and their predators. However, it can be difficult to distinguish predatory damage from mechanical breakage, thus making interpretation of damaged modern and fossil shells problematic. To establish a clear-cut distinction between antemortem predatory crab damage and ante- and postmortem mechanical damage in Mytilus trossulus shells, a combined field and experimental approach was used. Mussels were exposed to predation by crabs, tumbled-live, tumbled-dead, and trampled. After 100 h of tumbling, live-collected mussel shells were abraded and disarticulated but not otherwise damaged. Eight percent of the dead-collected shells were …

On The Use Of Modis Evi To Assess Gross Primary Productivity Of North American Ecosystems, Daniel A. Sims, Abdullah Rahman, Vicente D. Cordova, Bassil Z. El-Masri, Dennis D. Baldocchi, Lawrence B. Flanagan, Allen H. Goldstein, David Y. Hollinger, Laurent Misson, Russell K. Monson, Walter C. Oechel, Hans P. Schmid, Steven C. Wofsy, Liukang Xu

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

[1] Carbon flux models based on light use efficiency (LUE), such as the MOD17 algorithm, have proved difficult to parameterize because of uncertainties in the LUE term, which is usually estimated from meteorological variables available only at large spatial scales. In search of simpler models based entirely on remote‐sensing data, we examined direct relationships between the enhanced vegetation index (EVI) and gross primary productivity (GPP) measured at nine eddy covariance flux tower sites across North America. When data from the winter period of inactive photosynthesis were excluded, the overall relationship between EVI and tower GPP was better than that between …

Study Of Metals In Leached Soils Of A Municipal Dumpsite In Tampico, Tamaulipas, Mexico: Preliminary Results, P. F. Rodríguez-Espinosa, D. Chazaro Mendoza, J. A. Montes De Oca, G. Sánchez Torres E., Alejandro Fierro-Cabo

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The Zapote dumpsite measures 420000 m 2 and is 28 years old; an estimated 2.5 millions tons of waste have accumulated on the site (household waste, clinical waste, commercial waste). The thickness of the waste is 3 to 9 meters. Since operations began, no control regulations have existed on the residues received. The Zapote dumpsite is located within a salt-marsh between a system of channels and river lagoons of brackish water, located in a tropical sedimentary environment in the urban zone of Tampico, Tamaulipas, Mexico. Recently, the Zapote has been closed and work is presently underway in its rehabilitation since …

Detecting Submarine Groundwater Discharge With Synoptic Surveys Of Sediment Resistivity, Radium, And Salinity, John A. Breier, Crystaline F. Breier, Henrietta Edmonds

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

A synoptic geophysical and geochemical survey was used to investigate the occurrence and spatial distribution of submarine discharges of water to upper Nueces Bay, Texas. The 17 km survey incorporated continuous resistivity profiling; measurements of surface water salinity, temperature, and dissolved oxygen; and point measurements of dissolved Ra isotopes. The survey revealed areas of interleaving, vertical fingers of high and low conductivity extending up through 7 m of bay bottom sediments into the surface water, located within 100 m of surface salinity and dissolved Ra maxima along with peaks in water temperature and lows in dissolved oxygen. These results indicate …

Potential Of Modis Evi And Surface Temperature For Directly Estimating Per-Pixel Ecosystem C Fluxes, Abdullah Rahman, Daniel A. Sims, Vicente D. Cordova, Bassil Z. El-Masri

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

We tested the potential of estimating per-pixel gross primary production (GPP) directly from the MODIS enhanced vegetation index (EVI) and respiration directly from MODIS surface temperature (MOD11). Carbon flux data were obtained from 10 eddy covariance tower sites representing a wide range of North American vegetations. The correlation between across-site tower GPP and EVI was comparable (r = 0.77) to that between tower GPP and MOD17-GPP (r = 0.73), suggesting that EVI could be used to provide reasonably accurate direct estimates of GPP on a truly per-pixel basis. There was also a strong relationship (r2 = 0.67) between respiration and …

Oceanographic Conditions And Diversity Of Sea Stars (Echinodermata: Asteroidea) In The Gulf Of California, México, Carlos E. Cintra-Buenrostro, Hector Reyes-Bonilla, Maria Dinorah Herrero-Perezrul

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Species richness is one of the best indicators of biodiversity. However, there are few investigations on concordance of diversity patterns and environmental settings for marine regions. The objectives of this study were to correlate species richness of shallow water (< 200 m deep) sea stars with key oceanographic factors in the Gulf of California, México, and to predict species richness of Asteroidea using multiple regressions. In these analyses the Gulf was divided into nine sections of one degree in latitude (from 23 - 31° N), at each section we recorded: continental shelf area (at 100 and 200 m depth), temperature mean and range at three depth levels (0, 60 and 120 m), thermocline depth, surface nutrient concentrations (nitrates, phosphates and silicates), surface photosynthetic pigment concentration, and integrated productivity. Sea star species richness at each latitudinal section was estimated from literature data, new collections and museum records. Species were assigned to one of the following feeding guilds: predators of small mobile invertebrates (I), detritivores (D), predators of colonial organisms (C), generalist carnivores (G), and planktivores (P). There are 47 shallow water asteroid species in the Gulf of California (16 I, 15 D, eight C, six G, one P and one not assigned). Total species richness and guild species richness showed strong latitudinal attenuation patterns and were higher in the southernmost Gulf, an area characterized by a narrow shelf, high temperature, and low nutrient concentrations. Species diversity for each guild was correlated to a set of oceanographic parameters: temperature, nitrate concentration, and integrated productivity were linked to richness in must cases. We detected that nutrients and surface pigments always presented negative relationships with species richness, indicating that productive environments limit asteroid diversity in the study area. Finally, the postulated regression models to estimate species richness from oceanographic data were significant and highly precise. We conclude that species richness of Asteroidea in the Gulf of California is related to oceanographic conditions and can be estimated from regional oceanographic information.

Tracking The Sea-Level Signature Of The 8.2 Ka Cooling Event: New Constraints From The Mississippi Delta, Torbjörn E. Törnqvist, Scott J. Bick, Juan L. Gonzalez, Klaas Van Der Borg, Arie F. M. De Jong

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The ever increasing need for accurate predictions of global environmental change under greenhouse conditions has sparked immense interest in an abrupt, century‐scale cooling around 8200 years ago, with a focal point in the North Atlantic and with hemispheric teleconnections. Despite considerable progress in the unraveling of this striking feature, including a conceivable driving mechanism (rapid drainage of proglacial Lake Agassiz/Ojibway and a resulting reduced strength of North Atlantic thermohaline circulation), several key questions remain unanswered. One salient aspect concerns the total amount of freshwater released during this catastrophic event, likely echoed by a near‐instantaneous eustatic sea‐level rise. So far, no …

Potential Of Modis Ocean Bands For Estimating Co2 Flux From Terrestrial Vegetation: A Novel Approach, Abdullah Rahman, Vicente D. Cordova, John A. Gamon, Hans Peter Schmid, Daniel A. Sims

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

A physiologically-driven spectral index using two ocean-color bands of MODIS satellite sensor showed great potential to track seasonally changing photosynthetic light use efficiency (LUE) and stress-induced reduction in net primary productivity (NPP) of terrestrial vegetation. Based on these findings, we developed a simple ‘‘continuous field’’ model solely based on remotely sensed spectral data that could explain 88% of variability in flux-tower based daily NPP. For the first time, such a procedure is successfully tested at landscape level using satellite imagery. These findings highlight the unexplored potential of narrow-band satellite sensors to improve estimates of spatial and temporal distribution in terrestrial …

Supplemental Carbon Dioxide And Light Improved Tomato And Pepper Seedling Growth And Yield, Alejandro Fierro, Nicolas Tremblay, André Gosselin

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The experiment was conducted to determine the effects of CO, enrichment (900 μl·liter-1, 8 hours/day) in combination with supplementary lighting of 100 μmol·s-1·m-2 (16- h photoperiod) on tomato (Lycopersicon esculentum Mill.) and sweet pepper (Capsicum annuum L.) seedling growth in the greenhouse and subsequent yield in the field. Enrichment with CO2 and supplementary lighting for » 3 weeks before transplanting increased accumulation of dry matter in shoots by » 50% compared with the control, while root dry weight increased 49% for tomato and 6270 for pepper. Early yields increased by =1570 and 11% for tomato and pepper, respectively.