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Earth News, V39, Spring 2016, University Of Northern Iowa. Department Of Earth Science.

Earth News

Inside this issue:
--From the Department Head Siobahn Morgan
--News From the Faculty and Staff: Alan Czarnetzki, Paula Even, Kyle Gray, Chad Heinzel, Mohammad Iqbal, Lee Potter, Thomas Hockey, Nora Janssen, Aaron Spurr, Alexa Sedlacek, Xinhua Shen, Mike Stevens, Steve Smith
--News From Emeritus: Wayne Anderson
--Biggs Award 2015-Kyle Gray
--Hydrology News
--Impact
--Sunday at the Quarry
--Iowa Geological Summer Workshop
--Alumni Spotlight
--SGE
--Yellowstone Field Trip
--Big Bend Field Trip
--The Biogeochemical Evolution of the Atmosphere: The BETA Project
--Summer Undergraduate Research: Honors Thesis
--Wilderness First Aid (WFA)
--2015-16 EDMAP Project
--Graduates
--Internships
--Scholarships
--Student Research
--Seminars
--News From …

Global And Regional Chitinozoan Biodiversity Dynamics In The Ordovician: Relationships To Sea-Level, Carbon Cycling And Tectonics, Jordan Watson

Honors Theses

Fossil species provide extensive information about the past history of life on Earth. This thesis focuses on the global and regional biodiversity dynamics of the extinct fossil group Chitinozoa, and analyzes the impact and influences of sea-level, global carbon cycling and tectonics on their biodiversity. Biodiversity curves were generated from three different paleo-continents, Laurentia, Baltica, and Gondwana using the automated graphic correlation computer program CONOP9. Traditional methods of biodiversity analysis count fossil taxa in individual intervals of geologic time. The results of these methods are highly dependent upon interval length and the relationship of taxon range to interval boundaries. CONOP9 …

Extent Of Capillary Rise In Sands And Silts, Rachel Lynn Salim

Masters Theses

The values reported in literature for the height of capillary rise in fine sands, silts, and clays are contradictory. Most of the values were based on mathematical models, which used estimated rather than measured input data. This work measured capillary rise values in laboratory experiments in fine-grained sands and silts.

Two uniform sands with grains 0.35--0.7 mm in diameter and 0.3-0.6 mm in diameter, silt with an average grain size below 40 microns, and 0.35--0.7 mm sand coated with a water-repellant spray were carefully packed into two-inch diameter glass columns. These columns were placed into clear plastic tanks with water …

Low-Temperature Artificial Maturation Studies Of Type Ii And Type Iii Kerogens: Implications For Biogenic Gas Production, Albert Willy Nguena Kamga

Chemistry & Biochemistry Theses & Dissertations

Ancient organic matter (OM) in shales and coals, known mainly as Type II and Type III OM are known to produce both biogenic, thermogenic gas and oil. In this dissertation, mild artificial maturation, via closed system pyrolysis, is employed to determine the thermal reactivity of Type II and Type III OM beyond diagenesis. We select three Type II kerogens: i) Type II kerogen isolated from recent cores (3.3 Ma, Ro = 0.28) recovered from an upwelling basin in Namibia, Africa referred to as ODP Sediment, ii) Type II-S isolated from sediments (150 Ma, Ro = 0.38) recovered from an outcrop …

The Marine Cyanate Cycle, Brittany Widner

OES Theses and Dissertations

Cyanate (OCN-) is a reduced nitrogen compound with the potential to serve as a nitrogen and carbon source for marine microbes. Evidence from genomes and culture studies indicated that several marine cyanobacterial groups, including representatives of the globally important genera Synechococcus and Prochlorococcus, might be capable of cyanate assimilation. However, prior to this study, the distribution, bioavailability, and production pathways of cyanate were unknown in natural systems due to the absence of a sensitive cyanate assay; and the ability of organisms to assimilate cyanate on relevant timescales was unknown because we lacked a suitable tracer for measuring uptake. I developed …

Arsenic Mobilization From Silicic Volcanic Rocks In The Southern Willamette Valley, Gabriela Ribeiro De Sena Ferreira

Dissertations and Theses

Volcanic tuffs and tuffaceous sediments are frequently associated with elevated As groundwater concentrations even though their bulk As contents (~ 5 mg kg^-1; Savoie, 2013) are only marginally greater than the average crustal abundance of 4.8 mg g^-1 (Rudnick & Gao, 2003). Thus, As mobilization must be facilitated by conditions particular to these rocks. Alkaline desorption, anionic competition, reactive glass dissolution, and reductive dissolution of iron oxides are proposed processes of As release from volcanic rocks. Geogenic As contamination of groundwater in the southern Willamette Valley in western Oregon has been well-documented since the early 1960s, and …

Pengaruh Penambahan Arang Sekam Dan Jumlah Cabang Produksi Terhadap Pertumbuhan Tanaman, Hasil Dan Kualitas Buah Tomat Kultivar Doufu Hasil Sambung Batang Pada Inceptisol Jatinangor, Nasrulloh, Tino Mutiarawati, Wawan Sutari

Jurnal Kultivasi

Tomat beef merupakan salah satu jenis tomat yang mempunyai nilai ekonomis tinggi. Salah satu teknik budidaya yang dapat diguna-kan untuk meningkatkan produksi tanaman tomat yaitu perbaikan media tanam dengan penambahan arang sekam dan mengatur jumlah cabang produksi. Percobaan bertujuan untuk mempelajari berbagai dosis arang sekam dan jumlah cabang produksi yang baik untuk pertumbuhan, hasil dan kualitas tomat. Penelitian dilaksanakan di Laboratorium Kultur Terkendali, Fakultas Pertanian, Univer-sitas Padjadjaran di Jatinangor. Rancangan percobaan menggunakan Rancangan Petak Terbagi dengan tiga ulangan. Petak utama adalah penambahan arang sekam dengan empat taraf: 0%, 10%, 20%, 30% dan anak petak adalah jumlah cabang produksi dengan dua …

The Differing Biogeochemical And Microbial Signatures Of Glaciers And Rock Glaciers, Timothy S. Fegel, Jill S. Baron, Andrew G. Fountain, Gunnar F. Johnson, Ed K. Hall

Geology Faculty Publications and Presentations

Glaciers and rock glaciers supply water and bioavailable nutrients to headwater mountain lakes and streams across all regions of the American West. Here we present a comparative study of the metal, nutrient, and microbial characteristics of glacial and rock glacial influence on headwater ecosystems in three mountain ranges of the contiguous U.S.: the Cascade Mountains, Rocky Mountains, and Sierra Nevada. Several meltwater characteristics (water temperature, conductivity, pH, metals, nutrients, complexity of dissolved organic matter (DOM), and bacterial richness and diversity) differed significantly between glacier and rock glacier meltwaters, while other characteristics (Ca²+, Fe³+, SiO₂ concentrations, …

A Review Of Advances In The Identification And Characterization Of Groundwater Dependent Ecosystems Using Geospatial Technologies, Isabel C. Pérez Hoyos, Nir Y. Krakauer, Reza Khanbilvardi, Roy A. Armstrong

Publications and Research

Groundwater Dependent Ecosystem (GDE) protection is increasingly being recognized as essential for the sustainable management and allocation of water resources. GDE services are crucial for human well-being and for a variety of flora and fauna. However, the conservation of GDEs is only possible if knowledge about their location and extent is available. Several studies have focused on the identification of GDEs at specific locations using ground-based measurements. However, recent progress in remote sensing technologies and their integration with Geographic Information Systems (GIS) has provided alternative ways to map GDEs at a much larger spatial extent. This paper presents a review …

A Comparison Of Soil Hydrothermal Properties In Zonal And Uniform Tillage Systems Across The Us Corn Belt, Alwyn Williams, Adam S. Davis, Patrick M. Ewing, A. Stuart Grandy, Daniel A. Kane, Roger T. A. Koide, David A. Mortensen, Richard G. Smith, Sieglinde S. Snapp, Kurt A. Spokas, Anthony C. Yannarell, Nicholas R. Jordan

Faculty Publications

Zonal tillage (e.g. ridge tillage, RT) separates management of row and inter-row positions, while non-zonal tillage (e.g. chisel plough, CP) applies management uniformly across a field. This may have large effects on soil hydrothermal properties, affecting soil processes and crop development. We examined the effects of RT versus CP on soil hydrothermal conditions under maize (Zea mays L.) at four sites spanning the US Corn Belt over two growing seasons (2012–2013). We also investigated whether RT, as a result of changes in hydrothermal conditions, could stimulate greater soil nitrogen (N) availability during peak maize N demand. We captured wide variation …

A Global Empirical Typology Of Anthropogenic Drivers Of Environmental Change In Deltas, Zachary D. Tessler, Charles J. Vorosmarty, Michael Grossberg, Irina Gladkova, Hannah Aizenman

Advanced Science Research Center

It is broadly recognized that river delta systems around the world are under threat from a range of anthropogenic activities. These activities occur at the local delta scale, at the regional river and watershed scale, and at the global scale. Tools are needed to support generalization of results from case studies in specific deltas. Here, we present a methodology for quantitatively constructing an empirical typology of anthropogenic change in global deltas. Utilizing a database of environmental change indicators, each associated with increased relative sea-level rise and coastal wetland loss, a clustering analysis of 48 global deltas provides a quantitative assessment …

Soft Robotic Grippers For Biological Sampling On Deep Reefs, Kevin C. Galloway, Kaitlyn P. Becker, Brennan Phillips, Jordan Kirby, Stephen Licht, Dan Tchernov, Robert J. Wood, David F. Gruber

Publications and Research

This article presents the development of an underwater gripper that utilizes soft robotics technology to delicately manipulate and sample fragile species on the deep reef. Existing solutions for deep sea robotic manipulation have historically been driven by the oil industry, resulting in destructive interactions with undersea life. Soft material robotics relies on compliant materials that are inherently impedance matched to natural environments and to soft or fragile organisms. We demonstrate design principles for soft robot end effectors, bench-top characterization of their grasping performance, and conclude by describing in situ testing at mesophotic depths. The result is the first use of …

Nanoparticles Composed Of Zn And Zno Inhibit Peronospora Tabacina Spore Germination In Vitro And P. Tabacina Infectivity On Tobacco Leaves, George Wagner, Victor Korenkov, Jonathan D. Judy, Paul M. Bertsch

Plant and Soil Sciences Faculty Publications

Manufactured nanoparticles (NPs) are increasingly being used for commercial purposes and certain NP types have been shown to have broad spectrum antibacterial activity. In contrast, their activities against fungi and fungi-like oomycetes are less studied. Here, we examined the potential of two types of commercially available Zn NPs (Zn NPs and ZnO NPs) to inhibit spore germination and infectivity on tobacco leaves resulting from exposure to the fungi-like oomycete pathogen Peronospora tabacina (P. tabacina). Both types of NPs, as well as ZnCl₂ and bulk ZnO control treatments, inhibited spore germination compared to a blank control. ZnO ENMs …

Temperature Sensitivity Of Mineral Soil Carbon Decomposition In Shrub And Graminoid Tundra, West Greenland, Julia I. Bradley-Cook, Chelsea L. Petrenko, Andrew J. Friedland, Ross A. Virginia

Dartmouth Scholarship

Background:

Shrub expansion is transforming Arctic tundra landscapes, but the impact on the large pool of carbon stored in high-latitude soils is poorly understood. Soil carbon decomposition is a potentially important source of greenhouse gases, which could create a positive feedback to atmospheric temperature. Decomposition is temperature sensitive, but the response to temperature can be altered by environmental variables. We focus on mineral soils, which can comprise a substantial part of the near-surface carbon stock at the landscape scale and have physiochemical characteristics that influence temperature sensitivity. We conducted a soil incubation experiment to measure carbon dioxide (CO₂) …

Developing Probability Maps For Locating And Scouting Unprotected Areas Of Gravel Hill Prairies On Rodman Soils Along The Wabash River Valley Near Lafayette, Indiana, Ryan W.R. Schroeder

Engagement & Service-Learning Summit

No abstract provided.

Agenda: A Celebration Of The Work Of Charles Wilkinson: Served With Tasty Stories And Some Slices Of Roast, University Of Colorado Boulder. Getches-Wilkinson Center For Natural Resources, Energy, And The Environment

A Celebration of the Work of Charles Wilkinson (Martz Winter Symposium, March 10-11)

Conference held at the University of Colorado, Wolf Law Building, Wittemyer Courtroom, Thursday, March 10th and Friday, March 11th, 2016.

Conference moderators, panelists and speakers included University of Colorado Law School professors Phil Weiser, Sarah Krakoff, William Boyd, Kristen Carpenter, Britt Banks, Harold Bruff, Richard Collins, Carla Fredericks, Mark Squillace, and Charles Wilkinson

"We celebrate the work of Distinguished Professor Charles Wilkinson, a prolific and passionate writer, teacher, and advocate for the people and places of the West. Charles's influence extends beyond place, yet his work has always originated in a deep love of and commitment to particular places. We …

Prediction Of The Export And Fate Of Global Ocean Net Primary Production: The Exports Science Plan, David A. Siegel, Ken O. Buesseler, Michael J. Behrenfeld, Claudia R. Benitez-Nelson, Emmanuel Boss, Mark A. Brzezinski, Adrian Burd, Craig A. Carlson, Eric A. D'Asaro, Scott C. Doney, Mary J. Perry, Rachel H. R. Stanley, Deborah K. Steinberg

Faculty Publications

Ocean ecosystems play a critical role in the Earth's carbon cycle and the quantification of their impacts for both present conditions and for predictions into the future remains one of the greatest challenges in oceanography. The goal of the EXport Processes in the Ocean from Remote Sensing (EXPORTS) Science Plan is to develop a predictive understanding of the export and fate of global ocean net primary production (NPP) and its implications for present and future climates. The achievement of this goal requires a quantification of the mechanisms that control the export of carbon from the euphotic zone as well as …

Biomass Offsets Little Or None Of Permafrost Carbon Release From Soils, Streams, And Wildfire: An Expert Assessment, Benjamin W. Abbott, Jeremy B. Jones, Edward A.G. Schuur, F Stuart Chapin |||, William B. Bowden, Syndonia Bret-Harte, Nancy H.F. French, Et Al.

Michigan Tech Research Institute Publications

As the permafrost region warms, its large organic carbon pool will be increasingly vulnerable to decomposition, combustion, and hydrologic export. Models predict that some portion of this release will be offset by increased production of Arctic and boreal biomass; however, the lack of robust estimates of net carbon balance increases the risk of further overshooting international emissions targets. Precise empirical or model-based assessments of the critical factors driving carbon balance are unlikely in the near future, so to address this gap, we present estimates from 98 permafrost-region experts of the response of biomass, wildfire, and hydrologic carbon flux to climate …

Designing A Suite Of Measurements To Understand The Critical Zone, Susan L. Brantley, Roman A. Dibiase, Tess A. Russo, Yuning Shi, Henry Lin, Kenneth J. Davis, Margot Kaye, Lillian Hill, Jason Kaye, David M. Eissenstat, Beth Hoagland, Ashlee L.D. Dere, Andrew L. Neal, Kristen M. Brubaker, Dan K. Arthur

Geography and Geology Faculty Publications

Many scientists have begun to refer to the earth surface environment from the upper canopy to the depths of bedrock as the critical zone (CZ). Identification of the CZ as an integral object worthy of study implicitly posits that the study of the whole earth surface will provide benefits that do not arise when studying the individual parts. To study the CZ, however, requires prioritizing among the measurements that can be made – and we do not generally agree on the priorities. Currently, the Susquehanna Shale Hills Critical Zone Observatory (SSHCZO) is expanding from a small original focus area (0.08 …

Upscaling Methane Emission Hotspots In Boreal Peatlands, Fabio Cresto Aleina, Benjamin R. K. Runkle, Tim Brucher, Thomas Kleinen, Victor Brovkin

Biological and Agricultural Engineering Faculty Publications and Presentations

Upscaling the properties and effects of small-scale surface heterogeneities to larger scales is a challenging issue in land surface modeling. We developed a novel approach to upscale local methane emissions in a boreal peatland from the micro-topographic scale to the landscape scale. We based this new parameterization on the analysis of the water table pattern generated by the Hummock–Hollow model, a microtopography resolving model for peatland hydrology. We introduce this parameterization of methane hotspots in a global model-like version of the Hummock–Hollow model that underestimates methane emissions. We tested the robustness of the parameterization by simulating methane emissions for the …

Fire Disturbance Effects On Land Surface Albedo In Alaskan Tundra, Nancy H. F. French, Matthew A. Whitley, Liza K. Jenkins

Michigan Tech Research Institute Publications

The study uses satellite Moderate Resolution Imaging Spectroradiometer albedo products (MCD43A3) to assess changes in albedo at two sites in the treeless tundra region of Alaska, both within the foothills region of the Brooks Range, the 2007 Anaktuvuk River Fire (ARF) and 2012 Kucher Creek Fire (KCF). Results are compared to each other and other studies to assess the magnitude of albedo change and the longevity of impact of fire on land surface albedo. In both sites there was a marked decrease of albedo in the year following the fire. In the ARF, albedo slowly increased until 4 years after …

Michigan Geology: A Bibliography, March 2016, Peter Voice

MGRRE News

The Michigan Geological Survey produced a historic Index of Michigan Geology with an extensive bibliography in 1956. This current bibliography is an update of the bibliography in the Martin and Straight compilation. It is not comprehensive, but provides a starting place for anyone interested in Michigan Geology. The Michigan Geological Survey plans to update this bibliography periodically with newly published citations as well as other older citations we find.

Trace Element Inputs From Natural And Anthropogenic Sources In An Agricultural Watershed, Middle Provo River, Utah, Timothy Holman Goodsell

Theses and Dissertations

Water chemistry in rivers is impacted by a variety of natural and anthropogenic processes including agricultural runoff, urban runoff, storm runoff, groundwater inputs, and the built environment. In this study we used trace element concentrations (including As, B, Ce, Co, Cu, Li, Mn, Rb, Sb, Sr, Tl, V, and Zn) and continuous measurements of flow rates and specific conductance to investigate dynamic processes affecting water quality in a rapidly urbanizing agricultural area typical of the western U.S. The middle Provo River, located in northern Utah, USA, was selected as the study area because it is well instrumented with water quality …

Taphonomy Of Sediments: Bioturbation In The Triassic Moenkopi Formation In Southwestern Utah, James Vernon Bird Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

Measurement of bioturbation reflects physical and biological processes operating over time and can be used to reveal information about paleo-environments. The purpose of this study was to determine the intensity of bioturbation in Triassic Moenkopi Formation at Hurricane Mesa in Southwestern Utah. This formation is interpreted as having been deposited mostly in large ancient river channels, tidal flats, delta and shallow marine environments. Five stratigraphic sections measured in the Virgin Limestone Member provided the basis for this study. Detailed descriptions and quantification of bioturbation were recorded in each of the sections. Similar treatment was given to additional study sites in …

Comparative Transcriptome And Proteome Analysis To Reveal The Biosynthesis Of Gold Nanoparticles In Arabidopsis, Manish Tiwari, Sneha Krishnamurthy, Devesh Shukla, Jeffrey Kiiskila, Ajay Jain, Rupali Datta, Nilesh Sharma, Shivendra V. Sahi

Michigan Tech Publications, Part 1

© 2016, Nature Publishing Group. All rights reserved. A large number of plants have been tested and exploited in search of a green chemistry approach for the fabrication of gold or other precious metal nanomaterials. Despite the potential of plant based methods, very little is known about the underlying biochemical reactions and genes involved in the biotransformation mechanism of AuCl4 into gold nanoparticles (AuNPs). In this research, we thus focused on studying the effect of Au on growth and nanoparticles formation by analyses of transcriptome, proteome and ionome shift in Arabidopsis. Au exposure favored the growth of Arabidopsis seedling and …

A High-Resolution Mid-Pleistocene Temperature Record From Arctic Lake El'gygytgyn: A 50 Kyr Super Interglacial From Mis 33 To Mis 31?, Gregory De Wet, Isla S. Castañeda, Robert M. Deconto, Julie Brigham-Grette

Geosciences: Faculty Publications

Previous periods of extreme warmth in Earth's history are of great interest in light of current and predicted anthropogenic warming. Numerous so called "super interglacial" intervals, with summer temperatures significantly warmer than today, have been identified in the 3.6 million year (Ma) sediment record from Lake El'gygytgyn, northeast Russia. To date, however, a high-resolution paleotemperature reconstruction from any of these super interglacials is lacking. Here we present a paleotemperature reconstruction based on branched glycerol dialkyl glycerol tetraethers (brGDGTs) from Marine Isotope Stages (MIS) 35 to MIS 29, including super interglacial MIS 31. To investigate this period in detail, samples were …

Science Ama Series: Antarctic Peninsula Paleontology Project, Matt Lamanna, Julia Clarke, Pat O'Connor, Ross Macphee, Erik Gorscak, Abby West, Chris Torres, Kerin M. Claeson, Meng Jin, Steve Salisbury, Eric Roberts, Zubair Jinnah

PCOM Scholarly Works

Transcript of an online colloquium between members of the APPP expedition and readers of the online bulletin board Reddit.

Soil Functional Zone Management: A Vehicle For Enhancing Production And Soil Ecosystem Services In Row-Crop Agroecosystems, Alwyn Williams, Daniel A. Kane, Patrick M. Ewing, Lesley W. Atwood, Andrea Jilling, Meng Li, Yi Lou, Adam S. Davis, A. Stuart Grandy, Sheri C. Huerd, Mitchell C. Hunter, Roger T. Koide, David A. Mortensen, Richard G. Smith, Sieglinde S. Snapp, Kurt A. Spokas, Anthony C. Yannarell, Nicholas R. Jordan

Faculty Publications

There is increasing global demand for food, bioenergy feedstocks and a wide variety of bio-based products. In response, agriculture has advanced production, but is increasingly depleting soil regulating and supporting ecosystem services. New production systems have emerged, such as no-tillage, that can enhance soil services but may limit yields. Moving forward, agricultural systems must reduce trade-offs between production and soil services. Soil functional zone management (SFZM) is a novel strategy for developing sustainable production systems that attempts to integrate the benefits of conventional, intensive agriculture, and no-tillage. SFZM creates distinct functional zones within crop row and inter-row spaces. By incorporating …

Sediment Loads And Transport At Constructed Chutes Along The Missouri River-Upper Hamburg Chute Near Nebraska City, Nebraska, And Kansas Chute Near Peru, Nebraska, Brenda K. Densmore, David L. Rus, Matthew T. Moser, Brent M. Hall, Michael J. Andersen

United States Geological Survey: Water Reports and Publications

The United States Geological Survey (USGS), in cooperation with the United States Army Corps of Engineers, monitored suspended sediment within constructed Missouri River chutes during March through October 2012. Chutes were constructed at selected river bends by the US Army Corps of Engineers to help mitigate aquatic habitat lost through the creation and maintenance of the navigation channel on the Missouri River. The restoration and development of chutes is one method for creating shallow-water habitat within the Missouri River to meet requirements established by the amended 2000 Biological Opinion. Understanding geomorphic channel-evolution processes and sediment transport is important for the …

Cone-In-Cone And Beef Mineralization Associated With Triassic Growth Basin Faulting And Shallow Shale Diagenesis, Edgeøya, Svalbard, Harmon D. Maher Jr., Kei Ogata, Alvar Braathen

Geography and Geology Faculty Publications

Cone-in-cone (CIC) and beef (BF) carbonate lenses ornament detachment zone faults underlying Triassic growth basins on Edgeøya. Field relationships place CIC and BF growth as during early diagenesis and a transition from hydroplastic to a later brittle-style of faulting that is marked by coarser calcite veining. Deformation is constrained to have occurred at<300 mdepth. Multiple models exist for CIC formation. For the Edgeøya example, textural analysis of thin-sections suggests that small tensile fractures and carbonate shell fragments nucleated development of calcite aggregates with CIC and BF morphology within unconsolidated to poorly consolidated sediment to form asymmetric antitaxial tensile aggregates subparallel to bedding and fault surfaces. The conical forms result from differential growth on stepped, cleavage-parallel faces of fibres facing host sediment, with preferential inclusion incorporation at inner corners. The preferred directions of calcite growth are attributed to local stresses and seepage flow associated with pore pressure gradients. Substantial framboidal pyrite in the sediments represents an early phase of microbially driven sulphate reduction, which may have induced calcite mineralization. The transition to brittle-style faulting was marked by development of deformation twins in CIC/BF fibres, and a transition to coarse, blocky calcite growth in relay arrays of steeply oriented microveins. This indicates local fault-related stresses substantially changed during shallow diagenesis and lithification, an evolution attributed to changing pore pressures, seepage forces and material moduli. Calcite mineralizations at Edgeøya track the very significant changes in mechanical properties and stress states that occur during synlithification deformation at very shallow crustal levels.