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Pemanfaatan Beberapa Jenis Urin Ternak Sebagai Pupuk Organik Cair Dengan Konsentrasi Yang Berbeda Pada Tanaman Kelapa Sawit (Elaeis Guineensis Jacq.) Di Pembibitan Utama, Bisri Alvi, Mira Ariyanti, Yudithia Maxiselly Aug 2018

Pemanfaatan Beberapa Jenis Urin Ternak Sebagai Pupuk Organik Cair Dengan Konsentrasi Yang Berbeda Pada Tanaman Kelapa Sawit (Elaeis Guineensis Jacq.) Di Pembibitan Utama, Bisri Alvi, Mira Ariyanti, Yudithia Maxiselly

Jurnal Kultivasi

Pembibitan merupakan tahapan awal dalam budidaya tanaman kelapa sawit, kualitas bibit akan mempengaruhi hasil yang akan diperoleh nantinya. Faktor yang mempengaruhi pertumbuhan bibit diantaranya adalah ketersediaan unsur hara yang dapat diperoleh dari pemberian pupuk anorganik dan organik. Pemberian pupuk anorganik tanpa diimbangi pupuk organik dapat merusak sifat tanah, sehingga diperlukan pupuk organik yaitu dengan memanfaatkan urin ternak sebagai pupuk organik cair, dengan menambahkan pupuk organik cair pada tanah, maka dapat membantu proses pertumbuhan tanaman karena pupuk organik cair urin ternak mengandung hormon pertumbuhan bagi tanaman serta mudah diserap tanaman. Penelitian dilakukan di Kebun Percobaan Ciparanje, Fakultas Pertanian, Universitas Padjadjaran, Kabupaten …


Ancient Convergent Losses Of Paraoxonase 1 Yield Potential Risks For Modern Marine Mammals, Wynn K. Meyer, Jerrica Jamison, Rebecca Richter, Stacy E. Woods, Raghavendran Partha, Amanda Kowalczyk, Charles Kronk, Maria Chikina, Robert K. Bonde, Daniel E. Crocker, Joseph Gaspard, Janet M. Lanyon, Judit Marsillach, Clement E. Furlong, Nathan L. Clark Aug 2018

Ancient Convergent Losses Of Paraoxonase 1 Yield Potential Risks For Modern Marine Mammals, Wynn K. Meyer, Jerrica Jamison, Rebecca Richter, Stacy E. Woods, Raghavendran Partha, Amanda Kowalczyk, Charles Kronk, Maria Chikina, Robert K. Bonde, Daniel E. Crocker, Joseph Gaspard, Janet M. Lanyon, Judit Marsillach, Clement E. Furlong, Nathan L. Clark

United States Geological Survey: Staff Publications

Mammals diversified by colonizing drastically different environments, with each transition yielding numerous molecular changes, including losses of protein function. Though not initially deleterious, these losses could subsequently carry deleterious pleiotropic consequences. We have used phylogenetic methods to identify convergent functional losses across independent marine mammal lineages. In one extreme case, Paraoxonase 1 (PON1) accrued lesions in all marine lineages, while remaining intact in all terrestrial mammals. These lesions coincide with PON1 enzymatic activity loss in marine species’ blood plasma. This convergent loss is likely explained by parallel shifts in marine ancestors’ lipid metabolism and/or bloodstream oxidative environment affecting PON1’s role …


Influence Of Cover Crop Species On Soil Physical Properties In A Corn-Soybean Rotation, Addison D. Jacobs Aug 2018

Influence Of Cover Crop Species On Soil Physical Properties In A Corn-Soybean Rotation, Addison D. Jacobs

Student Theses and Dissertations

As crop land decreases and population increases, soil quality is becoming a concern. Utilizing cover crops in cropping systems could improve soil quality. This study examined 16 treatments of single-species cover crops, cover crop mixes, and two control treatments on a silt-loam soil, in a corn (Zea mays L.) - soybean (Glycine max L. Merr.) crop rotation under no-tillage, to determine their effect on soil physical properties. Cover crop biomass differed (p<0.10) among treatments and produced a maximum of 15.6 Mg ha-1 of biomass in the crimson clover treatment. Water infiltration rates increased as much as 282% in the complete-mix treatment compared to the fallow control. Differences in infiltration rates due to cover crop species were shown in two-years. However, these results suggest that it may take more time for cover crops to affect change in bulk density and aggregate stability.


Internal Parasites Of The Two Subspecies Of The West Indian Manatee Trichechus Manatus, Heidi Wyrosdick, Alycia Chapman, Antonio A. Mignucci-Giannoni, Carla I. Rivera-Pérez, Robert K. Bonde Aug 2018

Internal Parasites Of The Two Subspecies Of The West Indian Manatee Trichechus Manatus, Heidi Wyrosdick, Alycia Chapman, Antonio A. Mignucci-Giannoni, Carla I. Rivera-Pérez, Robert K. Bonde

United States Geological Survey: Staff Publications

The West Indian manatee Trichechus manatus is divided into 2 subspecies: the Antillean (T. m. manatus) and Florida (T. m. latirostris) manatees. This study reports sample prevalence of manatee parasites from populations of these 2 subspecies in different geographical locations. Although necropsy is a valuable diagnostic tool for parasite infections, the need for antemortem diagnostic techniques is important. Fecal samples collected during necropsies of Antillean manatees (n = 3) in Puerto Rico and Florida manatees (n = 10) in Crystal River, Florida, as well as from live-captured Florida manatees (n = 11) were evaluated using centrifugal …


The Evaluation Of Two Different Harvesting 'Topbunch' And 'Hi-Crop' Collards (Brassica Oleracea (L)) Leaves From Plants Grown In A Wiregrass Tunnel House, Edward Sparks, Raymon Shange, Jacquelyn Jackson, Victor Khan, James E. Currington, Ramble Ankumah, Nathaniel Ellison, George X. Hunter Jr., Jeffery L. Moore Aug 2018

The Evaluation Of Two Different Harvesting 'Topbunch' And 'Hi-Crop' Collards (Brassica Oleracea (L)) Leaves From Plants Grown In A Wiregrass Tunnel House, Edward Sparks, Raymon Shange, Jacquelyn Jackson, Victor Khan, James E. Currington, Ramble Ankumah, Nathaniel Ellison, George X. Hunter Jr., Jeffery L. Moore

Professional Agricultural Workers Journal

A study was conducted to determine if a 100% or 50% harvest intensity of ‘Topbunch’ collards leaves could be a recommended practice for Tunnel House producers. The experiment was conducted as a split-plot design with harvest dates as main plots, and harvesting intensity of 100% or 50% of leaves as sub-plots. All treatments were replicated three times, drip irrigated, and fertilized according to soil test recommendations. The results showed significant interactions between harvest methods and dates for number and weight of leaves harvested. There were also significant differences for the weight of leaves harvested and numbers. The leaf recovery rates …


Quantifying Plant Soluble Protein And Digestible Carbohydrate Content, Using Corn (Zea Mays) As An Exemplar, Carrie A. Deans, Gregory A. Sword, Paul A. Lenhart, Eric Burkness, William D. Hutchison, Spencer T. Behmer Aug 2018

Quantifying Plant Soluble Protein And Digestible Carbohydrate Content, Using Corn (Zea Mays) As An Exemplar, Carrie A. Deans, Gregory A. Sword, Paul A. Lenhart, Eric Burkness, William D. Hutchison, Spencer T. Behmer

Entomology Faculty Publications

Elemental data are commonly used to infer plant quality as a resource to herbivores. However, the ubiquity of carbon in biomolecules, the presence of nitrogen-containing plant defensive compounds, and variation in species-specific correlations between nitrogen and plant protein content all limit the accuracy of these inferences. Additionally, research focused on plant and/or herbivore physiology require a level of accuracy that is not achieved using generalized correlations. The methods presented here offer researchers a clear and rapid protocol for directly measuring plant soluble proteins and digestible carbohydrates, the two plant macronutrients most closely tied to animal physiological performance. The protocols combine …


Serum Proteins In Healthy And Diseased Florida Manatees (Trichechus Manatus Latirostris), J.W. Harvey, K.E. Harr, D. Murphy, M.T. Walsh, M. De Wit, R.K. Bonde Aug 2018

Serum Proteins In Healthy And Diseased Florida Manatees (Trichechus Manatus Latirostris), J.W. Harvey, K.E. Harr, D. Murphy, M.T. Walsh, M. De Wit, R.K. Bonde

United States Geological Survey: Staff Publications

A major goal of this study was to determine whether serum protein fractions of healthy Florida manatees differ with age, sex, or living environments (wild versus housed). A second goal was to determine which serum protein fractions vary in diseased versus healthy manatees. Serum protein fractions were determined using agarose gel electrophoresis. Healthy adults had slightly higher total serum protein and total globulin concentrations than younger animals. This largely resulted from an increase in gamma globulins with age. Total serum protein, albumin, alpha-1 globulin, beta globulin, and total globulin concentrations were slightly higher in housed manatees compared to wild manatees, …


Alaskan Marine Transgressions Record Out-Of-Phase Arctic Ocean Glaciation During The Last Interglacial, Louise Farquharson, Daniel Mann, Tammy M. Rittenour, Pamela Groves, Guido Grosse, Benjamin Jones Aug 2018

Alaskan Marine Transgressions Record Out-Of-Phase Arctic Ocean Glaciation During The Last Interglacial, Louise Farquharson, Daniel Mann, Tammy M. Rittenour, Pamela Groves, Guido Grosse, Benjamin Jones

Geosciences Faculty Publications

Ongoing climate change focuses attention on the Arctic cryosphere’s responses to past and future climate states. Although it is now recognized the Arctic Ocean Basin was covered by ice sheets and their associated floating ice shelves several times during the Late Pleistocene, the timing and extent of these polar ice sheets remain uncertain. Here we relate a relict barrier-island system on the Beaufort Sea coast of northern Alaska to the isostatic effects of a previously unrecognized ice shelf grounded on the adjacent continental shelf. A new suite of optically stimulated luminescence dates show that this barrier system formed during one …


Geotraces And Beyond: Studies Of Trace Elements In Coastal And Open Ocean Waters With An Emphasis On The Effects Of Oxygen Depletion And Hydrothermal Plumes, Peng Ho Aug 2018

Geotraces And Beyond: Studies Of Trace Elements In Coastal And Open Ocean Waters With An Emphasis On The Effects Of Oxygen Depletion And Hydrothermal Plumes, Peng Ho

Dissertations

We investigated various dissolved trace element (dTE) distributions in two distinct areas: the coastal northern Gulf of Mexico and the eastern tropical Pacific Ocean.

A multi-year (2007‒2011) chemical time series of eight stations in the western Mississippi Sound (MS) and northwestern Mississippi Bight (MB) was undertaken to examine the factors affecting chemical distributions in this dynamic region. Key findings include the frequent development of bottom water hypoxia in MB during late spring-summer, the likely contribution of submarine groundwater discharge (SGD) to the material flows, and observation of effects of episodic events including tropical storms and the opening of the Bonnet …


Lake Regionalization And Diatom Metacommunity Structuring In Tropical South America, Xavier Benito, Sherilyn C. Fritz, Miriam Steinitz-Kannan, Maria I. Vélez, Michael M. Mcglue Aug 2018

Lake Regionalization And Diatom Metacommunity Structuring In Tropical South America, Xavier Benito, Sherilyn C. Fritz, Miriam Steinitz-Kannan, Maria I. Vélez, Michael M. Mcglue

Earth and Environmental Sciences Faculty Publications

Lakes and their topological distribution across Earth's surface impose ecological and evolutionary constraints on aquatic metacommunities. In this study, we group similar lake ecosystems as metacommunity units influencing diatom community structure. We assembled a database of 195 lakes from the tropical Andes and adjacent lowlands (8°N–30°S and 58–79°W) with associated environmental predictors to examine diatom metacommunity patterns at two different levels: taxon and functional (deconstructed species matrix by ecological guilds). We also derived spatial variables that inherently assessed the relative role of dispersal. Using complementary multivariate statistical techniques (principal component analysis, cluster analysis, nonmetric multidimensional scaling, Procrustes, variance partitioning), we …


Seasonal Differences In Trace Element Concentrations And Distribution In Spartina Alterniflora Root Tissue, Huan Feng, Yu Qian, J. Kirk Cochran, Qingzhi Zhu, Christina Heilbrun, Li Li, Wen Hu, Hanfei Yan, Xiaojing Huang, Mingyuan Ge, Evgeny Nazareski, Yong S. Chu, Shinjae Yoo, Xuebin Zhang, Chang Jun Liu Aug 2018

Seasonal Differences In Trace Element Concentrations And Distribution In Spartina Alterniflora Root Tissue, Huan Feng, Yu Qian, J. Kirk Cochran, Qingzhi Zhu, Christina Heilbrun, Li Li, Wen Hu, Hanfei Yan, Xiaojing Huang, Mingyuan Ge, Evgeny Nazareski, Yong S. Chu, Shinjae Yoo, Xuebin Zhang, Chang Jun Liu

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The present study uses nanometer-scale synchrotron X-ray nanofluorescence to investigate season differences in concentrations and distributions of major (Ca, K, S and P) and trace elements (As, Cr, Cu, Fe and Zn) in the root system of Spartina alterniflora collected from Jamaica Bay, New York, in April and September 2015. The root samples were cross-sectioned at a thickness of 10 μm. Selected areas in the root epidermis and endodermis were mapped with a sampling resolution of 100 and 200 nm, varying with the mapping areas. The results indicate that trace element concentrations in the epidermis and endodermis vary among the …


Middle Permian (Late Guadalupian) Back-Reef Carbonate Of Panther Canyon, Apache Mountains, Trans-Pecos Texas, Joshua Caleb Moore Aug 2018

Middle Permian (Late Guadalupian) Back-Reef Carbonate Of Panther Canyon, Apache Mountains, Trans-Pecos Texas, Joshua Caleb Moore

Earth & Environmental Sciences Theses - Archive

In the Apache Mountains of West Texas, Middle Permian (Guadalupian) strata a portion of the Delaware Basin part of the Capitan Reef is well exposed in many canyons that cut through the northern escarpment in the eastern part of the mountains. In Panther Canyon, the massive part of the Capitan Reef is well exposed and overlain by a stratigraphic sequence of lagoonal carbonate deposits referred to the Yates and Tansill Formations. At the entrance to Panther Canyon, two sections of these stratified carbonate rocks have been measured and described: the PC7 section, 31.8 meters thick, with eight distinct packages and …


Convergent Evolution In The Euarchontoglires, Philip J.R. Morris, Samuel N.F. Cobb, Philip G. Cox Aug 2018

Convergent Evolution In The Euarchontoglires, Philip J.R. Morris, Samuel N.F. Cobb, Philip G. Cox

School of Geosciences Faculty and Staff Publications

Convergence—the independent evolution of similar phenotypes in distantly related clades—is a widespread and much-studied phenomenon. An often-cited, but hitherto untested, case of morphological convergence is that between the aye-aye and squirrels. The aye-aye (Daubentonia madagascariensis) is a highly unusual lemuriform primate that has evolved a dentition similar to that of rodents: it possesses large, ever-growing incisors which it uses to strip the bark from trees in order to feed on wood-boring beetle larvae. Indeed, such is the similarity that some of the earliest classifications of the aye-aye placed it in the squirrel genus Sciurus. Here, we aimed …


The Geotraces Intermediate Data Product 2017, Conwaygeotraces, Tim M. Conway Aug 2018

The Geotraces Intermediate Data Product 2017, Conwaygeotraces, Tim M. Conway

School of Geosciences Faculty and Staff Publications

The GEOTRACES Intermediate Data Product 2017 (IDP2017) is the second publicly available data product of the international GEOTRACES programme, and contains data measured and quality controlled before the end of 2016. The IDP2017 includes data from the Atlantic, Pacific, Arctic, Southern and Indian oceans, with about twice the data volume of the previous IDP2014. For the first time, the IDP2017 contains data for a large suite of biogeochemical parameters as well as aerosol and rain data characterising atmospheric trace element and isotope (TEI) sources. The TEI data in the IDP2017 are quality controlled by careful assessment of intercalibration results …


Flow Regime Influences On Stream And Riparian Soil Carbon Dynamics In The Ozark Highlands And Boston Mountains Of Arkansas, Allyn Dodd Aug 2018

Flow Regime Influences On Stream And Riparian Soil Carbon Dynamics In The Ozark Highlands And Boston Mountains Of Arkansas, Allyn Dodd

Graduate Theses and Dissertations

The natural flow regime exerts primacy over lotic ecosystem patterns and processes. However, little work has examined the influence of flow regime on instream and riparian carbon (C) dynamics in minimally-impacted, temperate forested systems. To date, most research efforts have focused on characterizing C movement and transformations across biomes and land use categories; however, flow regime represents an overlooked, finer level of detail that may drive differences in ecosystem function. My dissertation objective was to measure C fixation and movement within and across multiple environmental spheres (e.g. within stream channels, between stream surfaces and the atmosphere, and from riparian soils …


Stratigraphic Evaluation Of The St. Joe-Boone Boundary Interval, Kinderhookian-Osagean Series, Lower Mississippian System, Tri-State Region, Southern Midcontinent, Forrest Dalton Mcfarlin Aug 2018

Stratigraphic Evaluation Of The St. Joe-Boone Boundary Interval, Kinderhookian-Osagean Series, Lower Mississippian System, Tri-State Region, Southern Midcontinent, Forrest Dalton Mcfarlin

Graduate Theses and Dissertations

The Lower Mississippian interval comprises a single, third-order, eustatic cycle subdivided lithostratigraphically into the St. Joe Limestone (Hopkins 1893) and overlying Boone Formation (Branner 1891, Simonds 1891) with type areas in northern Arkansas. Coeval, homotaxial limestones occur in adjacent southwestern Missouri and northeastern Oklahoma. Missouri formation names for the St. Joe interval are recognized in Arkansas as members (ascending order): Bachelor, Compton, Northview, Pierson. The Boone interval in Missouri is represented by the (ascending order): Reeds Spring, Elsey, Burlington-Keokuk undifferentiated, but utilization of those names in Arkansas is problematic. in northern Arkansas, the Boone Formation is subdivided into informal lower …


Estimating Watershed Mercury Contribution To Lake Fort Smith State Park, Arkansas, Usa, William Miles Harmon Aug 2018

Estimating Watershed Mercury Contribution To Lake Fort Smith State Park, Arkansas, Usa, William Miles Harmon

Graduate Theses and Dissertations

Mercury contamination associated with human activities poses global human health and environmental risks. A fish-consumption advisory has been in effect at Lake Fort Smith in central west Arkansas for more than a decade due to observed methylmercury concentrations in fish tissue. Lake Fort Smith is an important municipal drinking water supply and recreational resource. Water samples from the majority contributing tributary stream, Frog Bayou creek, were collected periodically, under differing hydrologic conditions in order to quantify the allochthonous mercury load delivered to the lake. Temperature, specific conductance, and turbidity data were collected and used to estimate dissolved organic carbon, methylmercury …


Comparative Microbial Community Dynamics In A Karst Aquifer System And Proximal Surface Stream In Northwest Arkansas, Josue Rodriguez Aug 2018

Comparative Microbial Community Dynamics In A Karst Aquifer System And Proximal Surface Stream In Northwest Arkansas, Josue Rodriguez

Graduate Theses and Dissertations

Northwest Arkansas has well-developed karst systems, with numerous sinking streams and springs. Karst conduits make it easy for contaminants to enter groundwater systems, degrading the water quality and destroying fragile karst ecosystems. With the increase of urbanization, potential threats in the form of fecal contamination may prove to be more of a problem. The purpose of this research is to compare the difference between microbial communities within two different settings, a karst aquifer and a surface stream. The microbial communities within Blowing Spring Cave and Little Sugar Creek were detected and identified in water and sediment samples. Samples were also …


Distribution And Habitat Association Of The Northern Long-Eared Bat, Zachary A. Warren Aug 2018

Distribution And Habitat Association Of The Northern Long-Eared Bat, Zachary A. Warren

School of Natural Resources: Dissertations, Theses, and Student Research

Because of white-nose syndrome, the northern long-eared bat (Myotis septentrionalis) is experiencing rapid population declines across the majority of its range. This decline has prompted increased regulatory protection and thus an increased need for effective habitat management strategies. Insight into the species habitat associations, however, is a prior necessity to ensure management practices are biologically relevant. Understanding these relationships requires a holistic approach that addresses the multiple ways in which the species is interacting with its environment. The objective of my thesis was to address these relationships following a multi-scale approach that assessed the factors associated with roost …


A Comparison Of Vnir And Mir Spectroscopy For Predicting Various Soil Properties, Joshua R. Gates Aug 2018

A Comparison Of Vnir And Mir Spectroscopy For Predicting Various Soil Properties, Joshua R. Gates

School of Natural Resources: Dissertations, Theses, and Student Research

Soil plays an important role in our daily lives, namely producing food, cleaning water and storing carbon. The ability to rapidly and cost-effectively quantify the various components of soils can help us understand and better manage this important resource. This study aims to compare the ability of visible near-infrared (VNIR) spectroscopy and mid-infrared (MIR) spectroscopy to quickly and accurately predict various important soil properties (electrical conductivity, soil pH, cation exchange capacity, exchangeable cations, phosphorus, carbon, beta-glucosidase enzyme activity and nitrogen). Prediction models were developed using partial least squares regression (PLSR) techniques. Three different calibration sampling methods were tested along with …


Nutrient Transport And Storage In A Karst Spring-Reservoir System During Baseflow, Missouri Ozarks, Heather A. Moule Aug 2018

Nutrient Transport And Storage In A Karst Spring-Reservoir System During Baseflow, Missouri Ozarks, Heather A. Moule

Graduate Theses/Dissertations

Urban and agricultural land uses are important sources of nitrogen and phosphorus which, if in excess, can cause eutrophication in lakes and rivers. There have been few studies of nutrient transport and storage in karst spring and reservoir connected stream systems draining the Missouri Ozarks. This study aims to link the baseflow nutrient contributions of Sanders Spring to downstream reservoir outflow and the Headwaters South Dry Sac River Watershed in Springfield, Missouri. Water samples were collected seasonally and analyzed for total nitrogen (TN), total phosphorus (TP), and several other water quality parameters. Discharge was also monitored to calculate water and …


Evaporation Depth Controls The Relationship Between Soil Water Mobility And Soil Water Isotopic Composition, John Byars Shuler Aug 2018

Evaporation Depth Controls The Relationship Between Soil Water Mobility And Soil Water Isotopic Composition, John Byars Shuler

Boise State University Theses and Dissertations

Recent studies of plant water uptake assume that soil water isotopic composition can be used to infer soil water mobility. However, the strength of the relationship between mobility and isotopic composition remains poorly constrained. In addition, many ecohydrologic investigations are restricted by low sampling frequencies and insufficient soil moisture and matric potential data to support assumptions of soil water mobility. We sampled bulk soil water every 14 to 21 days in hillslope and riparian profiles during the 2016 and 2017 growing seasons in a semi-arid watershed outside Boise, ID. We collected twig samples of four tree and shrub species concurrently. …


Testing An Improved Method For Estimating The Unsaturated Hydraulic Conductivity Of Moderately Dry Soils, Sara Gedo Aug 2018

Testing An Improved Method For Estimating The Unsaturated Hydraulic Conductivity Of Moderately Dry Soils, Sara Gedo

UNLV Theses, Dissertations, Professional Papers, and Capstones

Prediction of water movement in the vadose zone requires knowledge of either the unsaturated hydraulic conductivity, K(θ), or the hydraulic diffusivity, D(θ), of the soil as a function of the moisture content. However, both K(θ) and D(θ) are difficult to obtain for moderately dry soils because the tests are time consuming and expensive. In order to address this issue, Globus and Gee (1995) developed a “heat pipe” method that allowed for the direct estimation of D(θ) and K(θ) for moderately dry soils on relatively short time scales. They proposed that exposing a sealed horizontal soil column to a steady thermal …


Improvement Of Soil Structure Through Organic Crop Management, Conservation Tillage And Grass-Clover Ley, Viviana Loaiza Puerta, Engil Isadora Pujol Pereira, Raphaël Wittwer, Marcel G. A. Van Der Heijden, Johan Six Aug 2018

Improvement Of Soil Structure Through Organic Crop Management, Conservation Tillage And Grass-Clover Ley, Viviana Loaiza Puerta, Engil Isadora Pujol Pereira, Raphaël Wittwer, Marcel G. A. Van Der Heijden, Johan Six

School of Earth, Environmental, & Marine Sciences Faculty Publications

Highlights

  • Organic crop management combined with reduced tillage improved soil structure.
  • The ley period improved soil structure for conventional intensive tillage.
  • The ley period increased total carbon in organic crop management at 0–6 cm soil depth.

Abstract

Conventional intensive tillage is a widespread soil management practice that controls weeds and promotes nutrient mineralization at the expense of a degraded soil structure and soil carbon (C) loss. Alternative soil management practices such as no tillage, reduced tillage and temporary leys, however, can minimize the negative effects of intensive tillage on soil structure. To improve understanding of these management practices on …


The Effect Of An Historical Geology Course On Students’ Attitudes Towards Science And Their Knowledge Of Deep Time As A Threshold To Their Knowledge Of Evolution, Allan Nolan Aug 2018

The Effect Of An Historical Geology Course On Students’ Attitudes Towards Science And Their Knowledge Of Deep Time As A Threshold To Their Knowledge Of Evolution, Allan Nolan

Dissertations

In America there exists a conflict between a small group of its citizens and the concept of evolution. Researchers have studied this conflict and the ways in which teachers might approach educational methodologies that not only address evolution in a sensitive manner, but also remain legally acceptable.

This research was designed to address teaching evolution in the context of deep time – the concept that time is vast and that geology and biology operate in a timescale of hundreds of millions to billions of years. In previous peer-reviewed works, it has been stated that deep time acts as a threshold …


Managing Herbicide Resistance: Listening To The Perspectives Of Practitioners. Procedures For Conducting Listening Sessions And An Evaluation Of The Process, Jill Schroeder, Michael Barrett, David R. Shaw, Amy B. Asmus, Harold Coble, David Ervin, Raymond A. Jussaume Jr., Micheal D. K. Owen, Ian Burke, Cody F. Creech, A. Stanley Culpepper, William S. Curran, Darrin M. Dodds, Todd A. Gaines, Jeffrey L. Gunsolus, Bradley D. Hanson, Prashant Jha, Annie E. Klodd, Andrew R. Kniss, Ramon G. Leon, Sandra Mcdonald, Don W. Morishita, Brian J. Schutte, Christy L. Sprague, Phillip W. Stahlman, Larry E. Steckel, Mark J. Vangessel Aug 2018

Managing Herbicide Resistance: Listening To The Perspectives Of Practitioners. Procedures For Conducting Listening Sessions And An Evaluation Of The Process, Jill Schroeder, Michael Barrett, David R. Shaw, Amy B. Asmus, Harold Coble, David Ervin, Raymond A. Jussaume Jr., Micheal D. K. Owen, Ian Burke, Cody F. Creech, A. Stanley Culpepper, William S. Curran, Darrin M. Dodds, Todd A. Gaines, Jeffrey L. Gunsolus, Bradley D. Hanson, Prashant Jha, Annie E. Klodd, Andrew R. Kniss, Ramon G. Leon, Sandra Mcdonald, Don W. Morishita, Brian J. Schutte, Christy L. Sprague, Phillip W. Stahlman, Larry E. Steckel, Mark J. Vangessel

Plant and Soil Sciences Faculty Publications

Seven half-day regional listening sessions were held between December 2016 and April 2017 with groups of diverse stakeholders on the issues and potential solutions for herbicide-resistance management. The objective of the listening sessions was to connect with stakeholders and hear their challenges and recommendations for addressing herbicide resistance. The coordinating team hired Strategic Conservation Solutions, LLC, to facilitate all the sessions. They and the coordinating team used in-person meetings, teleconferences, and email to communicate and coordinate the activities leading up to each regional listening session. The agenda was the same across all sessions and included small-group discussions followed by reporting …


Characterizing Polychlorinated Biphenyl Degradation Potential In Surface Water Bacteria From Rio Grande Valley, Texas Reservoirs, Alisha M. Janiga Aug 2018

Characterizing Polychlorinated Biphenyl Degradation Potential In Surface Water Bacteria From Rio Grande Valley, Texas Reservoirs, Alisha M. Janiga

Theses and Dissertations

The Donna Reservoir in Donna, Texas is contaminated with polychlorinated biphenyl (PCB) pollution. This reviews the current understanding of PCBs and investigate the potential of PCB degradation by native bacteria communities in the Donna Reservoir. The metabolic diversity, biphenyl tolerance, bphA1 presence were tested on surface water samples from the Donna Reservoir. The Ecoplate data suggest that the communities have a diverse metabolic capacity and the degree of plant life may interact with carbon type metabolism but not the rate of growth. Biphenyl growth curves showed that all the samples from the Donna Reservoir are tolerant to the average PCB …


Coastal Wetland Dynamics Under Sea-Level Rise And Wetland Restoration In The Northern Gulf Of Mexico Using Bayesian Multilevel Models And A Web Tool, Tyler Hardy Aug 2018

Coastal Wetland Dynamics Under Sea-Level Rise And Wetland Restoration In The Northern Gulf Of Mexico Using Bayesian Multilevel Models And A Web Tool, Tyler Hardy

Master's Theses

There is currently a lack of modeling framework to predict how relative sea-level rise (SLR), combined with restoration activities, affects landscapes of coastal wetlands with uncertainties accounted for at the entire northern Gulf of Mexico (NGOM). I developed such a modeling framework – Bayesian multi-level models to study the spatial pattern of wetland loss in the NGOM, driven by relative RSLR, vegetation productivity, tidal range, coastal slope, and wave height – all interacting with river-borne sediment availability, indicated by hydrological regimes. These interactions have not been comprehensively investigated before. I further modified this model to assess the efficacy of restoration …


Kinetic Processes And Stable Isotopes In Cave Dripwaters As Indicators Of Winter Severity, Vasile Ersek, Bogdan P. Onac, Aurel Perșoiu Aug 2018

Kinetic Processes And Stable Isotopes In Cave Dripwaters As Indicators Of Winter Severity, Vasile Ersek, Bogdan P. Onac, Aurel Perșoiu

School of Geosciences Faculty and Staff Publications

We examine how the stable isotope composition of meteoric water is transmitted through soil and epikarst to dripwaters in a cave in western Romania. δ2H and δ18O in precipitation at this site are influenced by temperature and moisture sources (Atlantic and Mediterranean), with lower δ18O in winter and higher in summer. The stable isotope composition of cave dripwaters mimics this seasonal pattern of low and high δ18O, but the onset and end of freezing conditions in the winter season are marked by sharp transitions in the isotopic signature of cave dripwaters of …


Universities Shaken By Earthquakes A Comparison Of Faculty And Student Experiences In Nepal And New Zealand, Rajendra Joshi, Jooyoung Kong, Heidi Nykamp, Herb Fynewever Aug 2018

Universities Shaken By Earthquakes A Comparison Of Faculty And Student Experiences In Nepal And New Zealand, Rajendra Joshi, Jooyoung Kong, Heidi Nykamp, Herb Fynewever

University Faculty Publications and Creative Works

The authors compare the experiences of faculty and students at universities in Nepal and New Zealand following earthquakes in 2015 and 2011, respectively. Questionnaire data from students at Kathmandu University are analyzed and compared with previously published data from the University of Canterbury. Prominent themes are developed within the context of the cultural and socioeconomic differences between the two settings. Both similarities and contrasts are described, detailing scheduling changes, the role of students in their community’s response to natural disaster, flexibility of faculty, psychological trauma and treatment, and use of online-learning as a substitute for classroom learning. Lessons learned from …