Life Sciences Commons^™

Discovery Of Juniperus Sabina Var. Balkanensis R. P. Adams And A. N. Tashev In Western Turkey (Anatolia), Robert P. Adams, Adam Boratynski, Tuğrul Mataraci, Alexander N. Tashev, Andrea E. Schwarzbach

Health & Biomedical Sciences Faculty Publications

Additional analyses of trnS-trnG and nrDNA from herbarium specimens from Europe revealed the presence of J. sabina var. balkanensis in western Turkey near Izmir and expands the range previously known only from Bulgaria and adjacent mountains in Greece. A more detailed map of the taxon's distribution is presented.

Dna Sequencing And Taxonomy Of Unusual Serrate Juniperus From Mexico: Chloroplast Capture And Incomplete Lineage Sorting In J. Coahuilensis And Allied Taxa, Robert P. Adams, M. Socorro Gonzalez-Elizondo, Martha Gonzalez-Elizondo, David Ramirez Noya, Andrea E. Schwarzbach

Health & Biomedical Sciences Faculty Publications

Analysis of nrDNA, petN-psbM, trnS-trnG, trmD-trnT, and trnF-trnL of Juniperus coahuilensis and allied taxa of Mexico found typical J. coahuilensis, as well as individuals with: coahuilensis cp and hybrid ITS; coahuilensis cp and novel ITS sequence (La Parrilla type); novel Blue Fruited cp (blue fruited taxon) and coahuilensis ITS; plus Blue Fruited cp and La Parrila ITS. nrDNA data was examined and found to detect hybridization, chloroplast capture and incomplete lineage sorting. In addition, a new taxon was found with Blue Fruited (Blue Fruited) cp and J. martinezii ITS, suggestive of chloroplast capture. New records of J. saltillensis were confirmed …

Survivorship And Growth Among Three Developmental Stages Of Black Mangrove (Avicennia Germinans) Seedlings In Southernmost Texas, Frank W. Judd, Kenneth R. Sunny, Robert I. Lonard, Ruben A. Mazariegos

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Black mangrove is useful for shoreline stabilization in Texas and Mexico but there is insufficient information regarding propagule survivorship and seedling growth. We compared survivorship and growth of three develop-mental groups of black mangrove seedlings planted on three dredge spoil islands in the Lower Laguna Madre of Texas, to better understand optimum planting strategy. Each spoil island had 100 seedlings without emergent radicles, 100 seedlings with emergent radicles, and 75 head-started seedlings. Survivorship of seedlings with and with-out emergent radicles was low, (0-16%). Survivorship of head-started seedlings was higher, (60 – 62.7%). Varia-tion in survivorship among developmental categories was significant …

Do Dynamic Global Vegetation Models Capture The Seasonality Of Carbon Fluxes In The Amazon Basin? A Data-Model Intercomparison, Natalia Restrepo-Coupe, Naomi M. Levine, Bradley O. Christoffersen, Loren P. Albert, Jin Wu, Marcos H. Costa, David Galbraith, Hewlley Imbuzeiro, Giordane Martins, Alessandro C. Da Araujo

School of Integrative Biological & Chemical Sciences Faculty Publications

To predict forest response to long-term climate change with high confidence requires that dynamic global vegetation models (DGVMs) be successfully tested against ecosystem response to short-term variations in environmental drivers, including regular seasonal patterns. Here, we used an integrated dataset from four forests in the Brasil flux network, spanning a range of dry-season intensities and lengths, to determine how well four state-of-the-art models (IBIS, ED2, JULES, and CLM3.5) simulated the seasonality of carbon exchanges in Amazonian tropical forests. We found that most DGVMs poorly represented the annual cycle of gross primary productivity (GPP), of photosynthetic capacity (Pc), and of other …

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) …

Effect Of Different Debranning Degrees On The Qualities Of Whole Wheat Flour And Chinese Steamed Bread, Jikai Zhao, Fengcheng Wang, Wenjun Fu, Mengjie Wang

School of Earth, Environmental, & Marine Sciences Faculty Publications

Abstract: Strong gluten, middle-strong gluten and middle gluten wheat were used as raw materials to obtain whole wheat flour by dry debranning process, and the effect of different debranning degrees on the quality of wheat kernel, whole wheat flour and Chinese steamed bread was evaluated. The results showed that the ash content, hardness index and thousand kernel weight of wheat kernels were decreased with increasing debranning degree by 0.17%, 1.0–1.5 and 1.74–1.82 g, respectively, whereas the volume weight was increased by 22.0–23.4 g/L. The contents of ash and damaged starch in whole wheat flour were decreased by 0.12%–0.14% and 1.0–2.1 …

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 …

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 …

The Breeding Bird Community Of A Remnant Urban Woodland In Mcallen, Texas, John S. Brush, Alexis Racelis, Timothy Brush

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

We conducted a breeding bird survey of a remnant thorn-forest at McAllen Nature Center in 2015 and 2016 to assess the breeding bird community and compare it to that of a larger, exurban refuge. We recorded 37 territorial species in McAllen Nature Center, including 15 species not reported at the exurban tract. Thirteen of these predominantly used the more open, human -maintained habitats in the northern and western sides of the park. The presence of many common thorn-forest birds, including a subset of the regions “South Texas specialty” species, is encouraging. Small remnant woodlands such as McAllen Nature Center may …

Autonomic Modulation In Older Women: Using Resistance Exercise As A Countermeasure, Hayden Gerhart, Yu Lun Tai, Curtis Fennell, Xian Mayo, J. Derek Kingsley

Health & Human Performance Faculty Publications

It is unclear if resistance training (RT) can be used to alter declines in autonomic modulation associated with aging. Young women (YW; range 18–25 yrs) and older women (OW; range 50–72 yrs) were compared at baseline. Only OW underwent supervised RT 2 days a week for 12-weeks. Baseline and post-training measurements included heart rate variability (HRV) and complexity (Sample Entropy) to assess autonomic modulation. The 12-weeks of RT consisted of 9 exercises performing 3 sets of 8–12 repetitions. At baseline, group differences in maximal strength, and autonomic modulation were evaluated with a one-way ANOVA with BMI as a covariate. In …

Protective Effect Of Anti-Phosphatidylserine Antibody In A Guinea Pig Model Of Advanced Hemorrhagic Arenavirus Infection, John M. Thomas, Philip E. Thorpe

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Objective: Host derived markers on virally infected cells or virions may provide targets for the generation of antiviral agents. Recently, we identified phosphatidylserine (PS) as a host marker of virions and virally-infected cells.

Methods and Materials: Under normal physiological conditions, PS is maintained on the inner leaflet of the plasma membrane facing the cytosol. Following viral infection, activation or pre-apoptotic changes cause PS to become externalized. We have previously shown that bavituximab, a chimeric human-mouse antibody that binds PS complexed with β2-glycoprotein I (β2GP1), protected rodents against lethal Pichinde virus and cytomegalovirus infections.

Results: Here, we determined the antiviral activity …

The Biological Flora Of Coastal Dunes And Wetlands: Avicennia Germinans (L.) L., Robert I. Lonard, Frank W. Judd, Kenneth R. Summy, Hudson R. Deyoe, Richard Stalter

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Avicennia germinans (L.) L. is a pantropical, subtropical, and occasionally warm-temperate mangrove species that occurs on shorelines that have a broad horizontal tidal range. Also known as black mangrove, stands typically develop under anoxic, water-logged conditions in substrates of silt or clay. Black mangrove can tolerate salinity values ranging from 0 to 90 parts per thousand. Salt is excreted from salt glands on both leaf epidermal surfaces, and aerosol salt spray and salt crystals are frequently observed on the upper leaf epidermis. Avicennia germinans is viviparous. The embryos have no dormancy requirements, and there is no seed bank. This mangrove …

Fish Oil With Higher Dha Content And Voluntary Exercise Decreases Postmenopausal Bone Loss, Jameela Banu, Gabriel Fernandes

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

There is increasing evidence suggesting that fish oil (FO) decreases bone resorption by reducing osteoclastogenesis and regular exercise (EX) increases bone mass. EX is associated with increasing bone formation. Therefore, the combined effects of FO intake and EX may have additive effects by both increasing bone formation and decreasing bone resorption. To demonstrate this, we studied the effects of FO and EX on the bone of mice after an ovariectomyinduced bone loss.

Twelve months old C57BL/6 female mice were either sham operated or ovariectomized, divided into different dietary and EX group and maintained for 3 months before sacrifice.

The distal …

Efectos Del Cambio Climático En La Interacción Planta-Hormiga: Una Mini Revisión Sobre La Tolerancia Térmica, Florencio Luna Castellanos, Mariana Cuautle, Teresa Patricia Feria-Arroyo, Citlalli Castillo Guevara

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Sin duda alguna el clima está cambiando debido al aumento de la concentración de gases de efecto invernadero en la atmósfera provocado por la acción humana. Dichos cambios van a tener un efecto importante en algunas actividades humanas tales como la agricultura y también pueden afectar enormemente la distribución geográfica de los organismos vivos y por tanto sus interacciones. Las hormigas y las plantas tienen una larga historia evolutiva de interacción. La actividad de las hormigas y su relación con las plantas en los últimos años ha tenido un número creciente de estudios que están poniendo de relieve su papel …

Carbon And Nitrogen Dynamics Of Anthropogenically Disturbed Seagrass Ecosystems, Alison Shepherd

Theses and Dissertations

As atmospheric CO2 concentrations continue to rise, understanding factors that influence size and longevity of carbon (C) pools within coastal and marine ecosystems (i.e., “blue carbon”) is critical. In 2013, the global average atmospheric CO2 concentration reached 396 ppm, which was the highest recorded level in the last 800,000 years. Recent research acknowledges the importance of “blue carbon” in the global C cycle, finding that these ecosystems capture up to 70% of organic C in the marine realm, rendering them one of the most efficient C sinks on the planet. Specifically, seagrass ecosystems are critically important to the global C …

Avian Communities In An Urbanizing Region: Abundance Patterns And Effects Of Local Habitat Features, John S. Brush

Theses and Dissertations

The Lower Rio Grande Valley of Texas has experience rapid population growth and increase of urban area since the mid-20th century. The goal of this thesis were to: 1) explore patterns of avian communities in suburban and remnant urban woodlands, with particular interest in native forest species, and 2) to assess how local habitat variables, such as number of native trees, affect avian communities in suburban habitats, and 3) provide recommendations to municipalities and homeowners to enhance urban habitats for birds. Results indicated that remnant urban woodlands provided habitat for common native forest bird species that otherwise avoided suburban habitats, …

Developing A Multimetric Index To Assess Resaca Ecosystem Health, Buford J. Lessley

Theses and Dissertations

As the only freshwater ecosystem in the lower Rio Grande Valley aside from the Rio itself, resacas are critical habitat for many species of flora and fauna. Old distributaries of the Rio Grande, resacas provided conveyance routes moving floodwater to the Laguna Madre. Today these wetlands are novel ecosystems and are artificially maintained. Urbanization and agriculture have lead to sedimentation, habitat loss, contaminants, poor water quality, and invasive species. The objective of this study was to assess and monitor resaca pools and to compose the Resaca Health Index (RHI) from selected indicators of ecosystem structure and function including leaf litter …

Conservación De Aves En México, Una Instantánea De 2015, Raúl Ortiz-Pulido, José L. Alcántara-Carbajal, Horacio De La Cueva, Juan Martínez-Gómez, Patricia Escalante Pliego, Sylvia M. De La Parra-Martínez, Teresa Patricia Feria-Arroyo, Steve Albert

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Más del 26% de las especies de aves que habitan en México está declinando. Los ornitólogos han propuesto diversas acciones para conservar algunas de ellas; sin embargo, se han hecho pocos esfuerzos por difundirlas. En este escrito, tomando en cuenta las nueve pláticas presentadas en un simposio científico realizado en 2015, resumimos la información sobre los esfuerzos de conservación de aves que se están llevando a cabo en el país. Dividimos los estudios en tres categorías: los que analizan cómo se hace la conservación en México, los que hacen conservación práctica y los que constituyen investigación ecológica básica tendiente a …

Foraging Patterns And Population Density Of The Buff-Bellied Hummingbird (Amazilia Yucatanensis) In Hidalgo County, Tx, Megan I. Villarreal

Theses and Dissertations

The objective of this investigation was to examine the foraging patterns and population density of the Buff-bellied Hummingbird (Amazilia yucatanensis ) in Hidalgo County, TX. Previous studies showed that hummingbirds use flowers displaying traditional bird pollination (ornithophilous) characteristics: reddish coloration, tubular corolla, and extended anthers. Observation sessions noted type and frequency of flowering species utilized for nectar, characteristics, and number of individuals seen in each area. Amazilia yucatanensis showed higher use of ornithophilous flowers. Significant results found: f-ratio 5.45 > p-value (0.05) 3.24. Two highly utilized species showed the expected 20–40% sucrose content expected in ornithophilous flowers. Population density per …

Sequencing Of The Complete Mitochondrial Genome Of Anastrepha Species, Francisco C. Rugama Ii

Theses and Dissertations

Several members of fruit flies in the vastly diverse Anastrepha (Schinner) genus (family Tephritidae), considered to be among the most important and devastating pests of vegetable and fruit crops, are distributed widely throughout the Americas. They attack several different kinds of fruit including citrus, which is of great economical importance in South Texas. The identification of these flies is based primarily on wing pattern and characteristics of the female genitalia, contrary to males, which cannot be distinguished at all. Misidentification of adults is a widespread problem, while identification at the larval stage is practically impossible. Currently, there are no published …

Effect Of Exotic Invasive Old World Climbing Fern (Lygodium Microphyllum) On Soil Properties, Pushpa G. Soti, Krish Jayachandran

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Old World climbing fern (Lygodium microphyllum) has become one of the most serious ecological threats to the integrity of the greater Everglades ecosystem of south Florida. In this study, we analyzed the effects of Old World climbing fern on surfacesoil characteristics at invaded sites in Florida. We compared soil characteristics of six invaded and adjacent uninvaded plots at three different locations. Our results show that the fern can grow and thrive in a wide range of soil types and the impact on the soil was site specific with effects being more prominent in sites with low nutrient status. Additionally, there …

Subspecific And Breeding Status Of The Common Yellowthroat (Geothlypis Trichas) At Santa Ana National Wildlife Refuge, Hidalgo County, Texas, Timothy Brush, Mark H. Conway

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

ABSTRACT—We confirmed the breeding of the Common Yellowthroat (Geothlypis trichas) during 2008–2015 at Santa Ana National Wildlife Refuge and presented measurement evidence that individuals belong to the Brownsville Common Yellowthroat, Geothlypis trichas insperata. This expands the known breeding distribution for this rare and local subspecies.

RESUMEN—Se confirm´o la reproducci´on de la mascarita com´un (Geothlypis trichas) durante 2008-2015 en Santa Ana National Wildlife Refuge y se presentaron pruebas de medici ´on que indican que los individuos pertenecen a la subespecie de mascarita com´un, Geothlypis trichas insperata. Esta informaci´on expande la distribuci´on de reproducci´on conocida de esta subespecie rara y local.

Calculating Evapotranspiration Of Arundo Donax Along The Rio Grande, Jose R. Escamilla Jr.

Theses and Dissertations

Invasive species have been recorded to cause large economic and ecological impacts on various ecosystems and their services. Locally, giant reed (Arundo donax L.), a woody grass native to the Mediterranean, adversely impacts riparian ecosystems in southwestern United States by aggressively displacing their native flora and fauna. Giant reed also has become a cause of concern for national water security, especially in water-limited areas of the arid southwestern United States. The main objective of this study is to provide the first, landscape-level estimates of water use by giant reed in the United States. Evapotranspiration was monitored using the eddy …

Linking Hydraulic Traits To Tropical Forest Function In A Size-Structured And Trait-Driven Model (Tfs V.1-Hydro), Bradley O. Christoffersen, Manuel Gloor, Sophie Fauset, Nikolaos M. Fyllas, David R. Galbraith, Timothy R. Baker, Bart Kruij, Lucy Rowland, Rosie A. Fisher, Oliver J. Binks

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Forest ecosystem models based on heuristic water stress functions poorly predict tropical forest response to drought partly because they do not capture the diversity of hydraulic traits (including variation in tree size) observed in tropical forests. We developed a continuous porous media approach to modeling plant hydraulics in which all parameters of the constitutive equations are biologically interpretable and measurable plant hydraulic traits (e.g., turgor loss point πtlp, bulk elastic modulus ε, hydraulic capacitance Cft, xylem hydraulic conductivity ks,max, water potential at 50 % loss of conductivity for both xylem (P50,x) and stomata ( …

A Principal Component Meta-Analysis On Multiple Anthropometric Traits Identifies Novel Loci For Body Shape, Janina S. Ried, Janina Jeff M., Audrey Y. Chu, Jennifer L. Bragg-Gresham, Jennifer E. Huffman, Tarunveer S. Ahluwalia, Gemma Cadby, Niina Eklund, John Blangero

School of Medicine Publications

Large consortia have revealed hundreds of genetic loci associated with anthropometric traits, one trait at a time. We examined whether genetic variants affect body shape as a composite phenotype that is represented by a combination of anthropometric traits. We developed an approach that calculates averaged PCs (AvPCs) representing body shape derived from six anthropometric traits (body mass index, height, weight, waist and hip circumference, waist-to-hip ratio). The first four AvPCs explain >99% of the variability, are heritable, and associate with cardiometabolic outcomes. We performed genome-wide association analyses for each body shape composite phenotype across 65 studies and meta-analysed summary statistics. …

One Health Interactions Of Chagas Disease Vectors, Canid Hosts, And Human Residents Along The Texas-Mexico Border, Melissa N. Garcia, Sarah O’Day, Susan P. Fisher-Hoch, Rodion Gorchakov, Ramiro Patino, Teresa Patricia Feria-Arroyo, Susan T. Laing, Joe E. Lopez, Alexandra Ingber, Kathryn M. Jones, Kristy O. Murray

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Background

Chagas disease (Trypanosoma cruzi infection) is the leading cause of non-ischemic dilated cardiomyopathy in Latin America. Texas, particularly the southern region, has compounding factors that could contribute to T. cruzi transmission; however, epidemiologic studies are lacking. The aim of this study was to ascertain the prevalence of T. cruzi in three different mammalian species (coyotes, stray domestic dogs, and humans) and vectors (Triatoma species) to understand the burden of Chagas disease among sylvatic, peridomestic, and domestic cycles.

Methodology/Principal Findings

To determine prevalence of infection, we tested sera from coyotes, stray domestic dogs housed in public …

Regulation Of Microvascular Flow And Metabolism: An Overview, Michelle A. Keske, Renee M. Dwyer, Ryan D. Russell, Sarah J. Blackwood, Aascha A. Brown, Donghua Hu, Dino Premilovac, Stephen M. Richards, Stephen Rattigan

Health & Human Performance Faculty Publications

Skeletal muscle is an important site for insulin to regulate blood glucose levels. It is estimated that skeletal muscle is responsible for ~80% of insulin-mediated glucose disposal in the post-prandial period. The classical action of insulin to increase muscle glucose uptake involves insulin binding to insulin receptors on myocytes to stimulate glucose transporter 4 (GLUT 4) translocation to the cell surface membrane, enhancing glucose uptake. However, an additional role of insulin that is often under-appreciated is its action to increase muscle perfusion thereby improving insulin and glucose delivery to myocytes. Either of these responses (myocyte and/or vascular) may be impaired …

Lack Of Interaction Between Erbb2 And Insulin Receptor Substrate Signaling In Breast Cancer, Sarah M. Farabaugh, Bonita T. Chan, Xiaojiang Cui, Robert Dearth, Adrian V. Lee

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Background: ErbB2 Receptor Tyrosine Kinase 2 (ErbB2, HER2/Neu) is amplified in breast cancer and associated with poor prognosis. Growing evidence suggests interplay between ErbB2 and insulin-like growth factor (IGF) signaling. For example, ErbB2 inhibitors can block IGF-induced signaling while, conversely, IGF1R inhibitors can inhibit ErbB2 action. ErbB receptors can bind and phosphorylate insulin receptor substrates (IRS) and this may be critical for ErbBmediated anti-estrogen resistance in breast cancer. Herein, we examined crosstalk between ErbB2 and IRSs using cancer cell lines and transgenic mouse models.

Methods: MMTV-ErbB2 and MMTV-IRS2 transgenic mice were crossed to create hemizygous MMTV-ErbB2/MMTVIRS2 bigenic mice. Signaling crosstalk …

Partitioning Controls On Amazon Forest Photosynthesis Between Environmental And Biotic Factors At Hourly To Interannual Timescales, Jin Wu, Kaiyu Guan, Matthew Hayek, Natalia Restrepo-Coupe, Kenia T. Wiedemann, Xiangtao Xu, Richard Wehr, Bradley O. Christoffersen, Guofang Miao, Rodrigo Da Silva

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Gross ecosystem productivity (GEP) in tropical forests varies both with the environment and with biotic changes in photosynthetic infrastructure, but our understanding of the relative effects of these factors across timescales is limited. Here, we used a statistical model to partition the variability of seven years of eddy covariance-derived GEP in a central Amazon evergreen forest into two main causes: variation in environmental drivers (solar radiation, diffuse light fraction, and vapor pressure deficit) that interact with model parameters that govern photosynthesis and biotic variation in canopy photosynthetic light-use efficiency associated with changes in the parameters themselves. Our fitted model was …