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Genomic And Transcriptomic Evidence For Scavenging Of Diverse Organic Compounds By Widespread Deep-Sea Archaea, Meng Li, Brett J. Baker, Karthik Anantharaman, Sunit Jain, John A. Breier, Gregory J. Dick Nov 2015

Genomic And Transcriptomic Evidence For Scavenging Of Diverse Organic Compounds By Widespread Deep-Sea Archaea, Meng Li, Brett J. Baker, Karthik Anantharaman, Sunit Jain, John A. Breier, Gregory J. Dick

School of Earth, Environmental, & Marine Sciences Faculty Publications

Microbial activity is one of the most important processes to mediate the flux of organic carbon from the ocean surface to the seafloor. However, little is known about the microorganisms that underpin this key step of the global carbon cycle in the deep oceans. Here we present genomic and transcriptomic evidence that five ubiquitous archaeal groups actively use proteins, carbohydrates, fatty acids and lipids as sources of carbon and energy at depths ranging from 800 to 4,950 m in hydrothermal vent plumes and pelagic background seawater across three different ocean basins. Genome-enabled metabolic reconstructions and gene expression patterns show that …


Impact Of Natural Organic Matter On Particle Behavior And Phototoxicity Of Titanium Dioxide Nanoparticles, Shibin Li, Hongbo Ma, Lindsay K. Wallis, Matthew A. Etterson, Benjamin Riley, Dale J. Hoff, Stephen A. Diamond Oct 2015

Impact Of Natural Organic Matter On Particle Behavior And Phototoxicity Of Titanium Dioxide Nanoparticles, Shibin Li, Hongbo Ma, Lindsay K. Wallis, Matthew A. Etterson, Benjamin Riley, Dale J. Hoff, Stephen A. Diamond

United States Environmental Protection Agency: Publications

Due to their inherent phototoxicity and inevitable environmental release, titanium dioxide nanoparticles (nano- TiO2) are increasingly studied in the field of aquatic toxicology. One of the particular interests is the interactions between nano-TiO2 and natural organic matter (NOM). In this study, a series of experiments was conducted to study the impacts of Suwannee River natural organic matter (SRNOM) on phototoxicity and particle behaviors of nano-TiO2. For Daphnia magna, after the addition of 5 mg/L SRNOM, LC50 value decreased significantly from 1.03 (0.89–1.20) mg/L to 0.26 (0.22–0.31) mg/L. For zebrafish larvae, phototoxic LC50 values were …


Changes In Litter Quality Caused By Simulated Nitrogen Deposition Reinforce The N-Induced Suppression Of Litter Decay, Linda T. A. Van Diepen, Serita D. Frey, Christopher M. Sthultz, Eric W. Morrison, Rakesh Minocha, Anne Pringle Oct 2015

Changes In Litter Quality Caused By Simulated Nitrogen Deposition Reinforce The N-Induced Suppression Of Litter Decay, Linda T. A. Van Diepen, Serita D. Frey, Christopher M. Sthultz, Eric W. Morrison, Rakesh Minocha, Anne Pringle

Faculty Publications

Rates of nitrogen (N) deposition are increasing in industrialized and rapidly developing nations. Simulated N deposition suppresses plant litter decay rates, in particular for low quality (high lignin) litter. Litter quality is a primary driver of litter decomposition; however, it is not clear how changes in litter quality caused by long-term ecosystem exposure to chronic N additions interact with altered soil N-availability to influence litter decay dynamics. To document the effects of simulated N deposition on litter quality, we conducted a meta-analysis of available litter nutrient data from simulated N deposition experiments in temperate forests. To directly test whether changes …


A Bat-Guano-Derived Δ15N And Δ13C Record Of Paleoenvironmental Change: Zidită Cave, Romania, Daniel Martin Cleary Oct 2015

A Bat-Guano-Derived Δ15N And Δ13C Record Of Paleoenvironmental Change: Zidită Cave, Romania, Daniel Martin Cleary

USF Tampa Graduate Theses and Dissertations

Because nitrogen isotopes are fractionated along the soil-plant-insect-bat-guano pathway, it may be possible to reconstruct environmental and climatic changes reflected in the nitrogen isotopic composition of guano. A 1.5-m core of bat guano from Zidită Cave (western Romania) provides a record of climatic and anthropogenic influence on the regional nitrogen cycle and paleoenvironmental controls on nitrogen transforming processes. Increasing and decreasing trends of nitrogen isotopic composition (δ15N values) correspond well with changes in the influence of farming practices, deforestation, and forest expansion. These influences likely had a significant effect on the openness of the nitrogen cycle, resulting in …


The Vulnerability Of Indo-Pacific Mangrove Forests To Sea-Level Rise, Catherine E. Lovelock, Donald R. Cahoon, Daniel A. Friess, Glenn R. Guntenspergen, Ken W. Krauss, Ruth Reef, Kerrylee Rogers, Megan L. Saunders, Frida Sidik, Andrew Swales, Neil Saintilan, Le Xuan Thuyen, Tran Triet Oct 2015

The Vulnerability Of Indo-Pacific Mangrove Forests To Sea-Level Rise, Catherine E. Lovelock, Donald R. Cahoon, Daniel A. Friess, Glenn R. Guntenspergen, Ken W. Krauss, Ruth Reef, Kerrylee Rogers, Megan L. Saunders, Frida Sidik, Andrew Swales, Neil Saintilan, Le Xuan Thuyen, Tran Triet

United States Geological Survey: Staff Publications

Sea-level rise can threaten the long-term sustainability of coastal communities and valuable ecosystems such as coral reefs, salt marshes and mangroves1,2. Mangrove forests have the capacity to keep pace with sea-level rise and to avoid inundation through vertical accretion of sediments, which allows them to maintain wetland soil elevations suitable for plant growth3. The Indo- Pacific region holds most of the world’s mangrove forests4, but sediment delivery in this region is declining, owing to anthropogenic activities such as damming of rivers5. This decline is of particular concern because the Indo-Pacific region is …


A Modern Gate For Ezells Cave, Texas, Jim "Crash" Kennedy Oct 2015

A Modern Gate For Ezells Cave, Texas, Jim "Crash" Kennedy

National Cave and Karst Management Symposia

No abstract provided.


Cave Research Projects Help Promote Diversity In The Geosciences, De'etra Young, Shannon Trimboli, Thomas Bly Oct 2015

Cave Research Projects Help Promote Diversity In The Geosciences, De'etra Young, Shannon Trimboli, Thomas Bly

National Cave and Karst Management Symposia

No abstract provided.


An Education Is Not All Derived From Textbooks”: A Century Of Interactions Between Mammoth Cave And Western Kentucky University, Chris Groves, Deana Groves, Weldon Hawkins Oct 2015

An Education Is Not All Derived From Textbooks”: A Century Of Interactions Between Mammoth Cave And Western Kentucky University, Chris Groves, Deana Groves, Weldon Hawkins

National Cave and Karst Management Symposia

No abstract provided.


Genus-Wide Assessment Of Bactrurus (Amphipoda: Crangonyctidae) Informs Conservation And Management Of Groundwater Habitats, Matthew L. Niemiller, Steven J. Taylor Oct 2015

Genus-Wide Assessment Of Bactrurus (Amphipoda: Crangonyctidae) Informs Conservation And Management Of Groundwater Habitats, Matthew L. Niemiller, Steven J. Taylor

National Cave and Karst Management Symposia

No abstract provided.


Cave And Karst Resource Management At Joint Base San Antonio-Camp Bullis, Chris Thibodaux Oct 2015

Cave And Karst Resource Management At Joint Base San Antonio-Camp Bullis, Chris Thibodaux

National Cave and Karst Management Symposia

No abstract provided.


Karst Wreckage: Subterranean Fauna As Collateral Damage, Julian J. Lewis, Salisa L. Lewis Oct 2015

Karst Wreckage: Subterranean Fauna As Collateral Damage, Julian J. Lewis, Salisa L. Lewis

National Cave and Karst Management Symposia

No abstract provided.


Managing The Spread Of Pseudogymnoascus Destructans And Conserving Bats Threatened By White-Nose Syndrome In North America, Jeremy Coleman, Jonathan D. Reichard, Richard Geboy, Christopher Servheen, Christina Kocer, Mike Armstrong Oct 2015

Managing The Spread Of Pseudogymnoascus Destructans And Conserving Bats Threatened By White-Nose Syndrome In North America, Jeremy Coleman, Jonathan D. Reichard, Richard Geboy, Christopher Servheen, Christina Kocer, Mike Armstrong

National Cave and Karst Management Symposia

No abstract provided.


Strip Adaptive Cluster Sampling With Application To Cave Crickets, Kurt Lewis Helf Oct 2015

Strip Adaptive Cluster Sampling With Application To Cave Crickets, Kurt Lewis Helf

National Cave and Karst Management Symposia

No abstract provided.


Monitoring In-Cave Resources With Reduced Impact And Increased Quantitative Capacity: Developing Photogrammetry Methodologies For In Cave Environments, Robyn L. Henderek, John R. Wood, Benjamin W. Tobin Oct 2015

Monitoring In-Cave Resources With Reduced Impact And Increased Quantitative Capacity: Developing Photogrammetry Methodologies For In Cave Environments, Robyn L. Henderek, John R. Wood, Benjamin W. Tobin

National Cave and Karst Management Symposia

No abstract provided.


The Extirpation Of A Population Of The Endangered Illinois Cave Amphipod (Gammarus Acherondytes) By An Exotic Species: The Wednesday Cave Debacle, Julian J. Lewis, Salisa L. Lewis Oct 2015

The Extirpation Of A Population Of The Endangered Illinois Cave Amphipod (Gammarus Acherondytes) By An Exotic Species: The Wednesday Cave Debacle, Julian J. Lewis, Salisa L. Lewis

National Cave and Karst Management Symposia

No abstract provided.


White-Nose Syndrome Response At Mammoth Cave National Park, Rickard S. Toomey Oct 2015

White-Nose Syndrome Response At Mammoth Cave National Park, Rickard S. Toomey

National Cave and Karst Management Symposia

No abstract provided.


Improving Stormwater Treatment Efficiency Based On Runoff Properties At Mammoth Cave National Park, Hung-Wai Ho, Rickard Toomey Oct 2015

Improving Stormwater Treatment Efficiency Based On Runoff Properties At Mammoth Cave National Park, Hung-Wai Ho, Rickard Toomey

National Cave and Karst Management Symposia

No abstract provided.


Finding Springs In The File Cabinet, Mason Johnson, Ashley Ignatius Oct 2015

Finding Springs In The File Cabinet, Mason Johnson, Ashley Ignatius

Sinkhole Conference 2015

The Minnesota Pollution Control Agency (MPCA), in partnership with other agencies, is currently undertaking comprehensive sub-basin assessments statewide over a ten-year period. Southeast Minnesota has over 17,500 kilometers of perennial and intermittent streams, making the task of comprehensive sub-basin assessment challenging; the task is further complicated by karst geology. In the summer of 2014, a pilot project began between the MPCA and Minnesota Department of Natural Resources (DNR) to digitally preserve paper documents which capture qualitative and quantitative data about the hydrology, water chemistry, geomorphology, biology, land use and karst features of southeast Minnesota streams. The paper documents in file …


Legacy Data In The Minnesota Spring Inventory, Greg Brick Oct 2015

Legacy Data In The Minnesota Spring Inventory, Greg Brick

Sinkhole Conference 2015

Past spring inventories have covered certain parts of Minnesota reasonably well, notably, the springs of the Minneapolis-St. Paul metropolitan area and the southeastern Minnesota karst. But hitherto, there has not been a systematic effort to create a uniform statewide inventory. The first step, before hunting down new springs, was to compile existing data and the most fruitful source of hydrological legacy data for the Minnesota spring inventory was the DNR Fisheries files. Once entered into a GIS-capable database, these spring locations can help “seed the ground” so that when crews finally do take to the field to map more springs, …


Using Nitrate, Chloride, Sodium, And Sulfate To Calculate Groundwater Age, Kimm Crawford, Terry Lee Oct 2015

Using Nitrate, Chloride, Sodium, And Sulfate To Calculate Groundwater Age, Kimm Crawford, Terry Lee

Sinkhole Conference 2015

Regression analysis is used to identify monotonic trends to assign water age using ion data from two large well water databases from southeast Minnesota (SE MN). Nitrate (NO3-N), chloride (Cl), sodium (Na), and sulfate (SO4) ions in the commonly used aquifers in SE MN can be used as groundwater tracers since they are either entirely or partly anthropogenic in their sources, their loading occurs on a regional scale, and they are almost entirely conserved. Ion concentrations over time are used to establish six trend patterns. Two patterns are unchanging (background and stable above background), and four are changing (linear up, …


Hydrologic And Geochemical Dynamics Of Vadose Zone Recharge In A Mantled Karst Aquifer: Results Of Monitoring Drip Waters In Mystery Cave, Minnesota, Daniel H. Doctor, E. Calvin Alexander Jr., Roy Jameson, Scott C. Alexander Oct 2015

Hydrologic And Geochemical Dynamics Of Vadose Zone Recharge In A Mantled Karst Aquifer: Results Of Monitoring Drip Waters In Mystery Cave, Minnesota, Daniel H. Doctor, E. Calvin Alexander Jr., Roy Jameson, Scott C. Alexander

Sinkhole Conference 2015

Caves provide direct access to flows through the vadose zone that recharge karst aquifers. Although many recent studies have documented the highly dynamic processes associated with vadose zone flows in karst settings, few have been conducted in mantled karst settings, such as that of southeastern Minnesota. Here we present some results of a long-term program of cave drip monitoring conducted within Mystery Cave, Minnesota. In this study, two perennial ceiling drip sites were monitored between 1997 and 2001. The sites were located about 90 m (300 ft) apart along the same cave passage approximately 18 m (60 ft) below the …


Management Options For Water-Repellent Soils In Australian Dryland Agriculture, M. M. Roper, S. L. Davies, P. S. Blackwell, D. J. M. Hall, D. Bakker, R. Jongepier, P. R. Ward Oct 2015

Management Options For Water-Repellent Soils In Australian Dryland Agriculture, M. M. Roper, S. L. Davies, P. S. Blackwell, D. J. M. Hall, D. Bakker, R. Jongepier, P. R. Ward

Natural Resources Research Articles

Water-repellent (‘non-wetting’) soils are a major constraint to agricultural production in southern and south-west Australia, affecting >10 Mha of arable sandy soils. The major symptom is dry patches of surface soil, even after substantial rainfall, directly affecting agricultural production through uneven crop and pasture germination, and reduced nutrient availability. In addition, staggered weed germination impedes effective weed control, and delayed crop and pasture germination increases the risk of wind erosion. Water repellency is caused by waxy organic compounds derived from the breakdown of organic matter mostly of plant origin. It is more prevalent in soils with a sandy surface texture; …


Modeling Micro-Topographic Controls On Boreal Peatland Hydrology And Methane Fluxes, F. Cresto Aleina, Benjamin R. K. Runkle, T. Kleinen, Lars Kutzbach, J. Schneider, V. Brovkin Oct 2015

Modeling Micro-Topographic Controls On Boreal Peatland Hydrology And Methane Fluxes, F. Cresto Aleina, Benjamin R. K. Runkle, T. Kleinen, Lars Kutzbach, J. Schneider, V. Brovkin

Biological and Agricultural Engineering Faculty Publications and Presentations

Small-scale surface heterogeneities can influence land-atmosphere fluxes and therefore carbon, water and energy budgets on a larger scale. This effect is of particular relevance for high-latitude ecosystems, because of the great amount of carbon stored in their soils. We introduce a novel micro-topographic model, the Hummock-Hollow (HH) model, which explicitly represents small-scale surface elevation changes. By computing the water table at the small scale, and by coupling the model with a process-based model for soil methane processes, we are able to model the effects of micro-topography on hydrology and methane emissions in a typical boreal peatland. In order to assess …


Interannual And Subdecadal Variability In The Nutrient Geochemistry Of The Cariaco Basin, Mary I. Scranton, Gordon T. Taylor, Robert Thunell, Claudia R. Benitez-Nelson, Frank Muller-Karger, Kent Fanning, Laura Lorenzoni, Enrique Montes, Ramon Varela, Yrene Astor Oct 2015

Interannual And Subdecadal Variability In The Nutrient Geochemistry Of The Cariaco Basin, Mary I. Scranton, Gordon T. Taylor, Robert Thunell, Claudia R. Benitez-Nelson, Frank Muller-Karger, Kent Fanning, Laura Lorenzoni, Enrique Montes, Ramon Varela, Yrene Astor

Faculty Publications

The CARIACO Ocean Time Series program has made monthly measurements of oxygen, nutrients, and carbon system parameters (∑CO2, alkalinity, pH) in the Cariaco Basin since 1996. At the same time, sediment traps have collected settling particles at four to five depths ranging from 150 to 1,200 m. The depth of the transition from oxic to anoxic conditions has fluctuated dramatically over the time series due to changes in the occurrence of Caribbean water intrusions into the deep basin. Nutrient concentrations in the deep basin have increased steadily with time in a proportion reflective of the elemental ratios in the settling …


Long-Term Manure Amendments Reduced Soil Aggregate Stability Via Redistribution Of The Glomalin-Related Soil Protein In Macroaggregates, Hongtu Xie, Jianwei Li, Bin Zhang, Lianfeng Wang, Jingkuan Wang, Hongbo He, Xudong Zhang Oct 2015

Long-Term Manure Amendments Reduced Soil Aggregate Stability Via Redistribution Of The Glomalin-Related Soil Protein In Macroaggregates, Hongtu Xie, Jianwei Li, Bin Zhang, Lianfeng Wang, Jingkuan Wang, Hongbo He, Xudong Zhang

Agricultural and Environmental Sciences Faculty Research

Glomalin-related soil protein (GRSP) contributes to the formation and maintenance of soil aggregates, it is however remains unclear whether long-term intensive manure amendments alter soil aggregates stability and whether GRSP regulates these changes. Based on a three-decade long fertilization experiment in northeast China, this study examined the impact of long-term manure input on soil organic carbon (SOC), total and easily extractable GRSP (GRSPt and GRSPe) and their respective allocations in four soil aggregates (>2000 μm; 2000–250 μm; 250–53 μm; and <53 μm). The treatments include no fertilization (CK), low and high manure amendment (M1, M2), chemical nitrogen, phosphorus and potassium fertilizers (NPK) and combined manure and chemical fertilizers (NPKM1, NPKM2). Though SOC, GRSPe and GRSPt in soil and SOC in each aggregate generally increased with increasing manure input, GRSPt and GRSPe in each aggregate showed varying changes with manure input. Both GRSP in macroaggregates (2000–250 μm) were significantly higher under low manure input, a pattern consistent with changes in soil aggregate stability. Constituting 38~49% of soil mass, macroaggregates likely contributed to the nonlinear changes of aggregate stability under manure amendments. The regulatory process of GRSP allocations in soil aggregates has important implications for manure management under intensive agriculture.


Droughtscape, Fall 2015, Kelly Smith Oct 2015

Droughtscape, Fall 2015, Kelly Smith

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

Director’s column.

NDMC 20th anniversary 2

Employment opportunity

Third quarter 2015 climate summary

Third quarter 2015 impacts summary

Workshop in Ethiopia

San Antonio multi-hazard tournament

Healthy soil is drought buffer

U2U Award

Cost-benefit analysis for utilities managing drought

NDMC helps with rural poll questions on climate

Introducing our post-docs

South Korean visitors


Water Quality In The Río Pastaza Watershed A Comparative Study Of Ríos Topo, Zuñag, And Pastaza And The Impact Of The Topo Hydroelectric Project Using Macroinvertebrates As Bioindicators, Jesse Vega-Perkins Oct 2015

Water Quality In The Río Pastaza Watershed A Comparative Study Of Ríos Topo, Zuñag, And Pastaza And The Impact Of The Topo Hydroelectric Project Using Macroinvertebrates As Bioindicators, Jesse Vega-Perkins

Independent Study Project (ISP) Collection

Ríos Zuñag, Pastaza, and Topo flow through one of the rainiest and water-rich places in Ecuador. Río Zuñag is a relatively small, pristine montane river and Río Pastaza is a relatively large, contaminated river that receives the untreated wastewater of many communities. Río Topo’s unique watershed and gradient allow it to be home to many plants that have adapted to its unique environment, including the hyperendemic liverwort Myriocolea irrorata. However, in recent years, all of the water of Río Topo has been sold by the state of Ecuador to be developed for hydroelectric projects (HEP). The first of these …


The Rise Of Fire: Fossil Charcoal In Late Devonian Marine Shales As An Indicator Of Expanding Terrestrial Ecosystems, Fire, And Atmospheric Change, Susan M. Rimmer, Sarah J. Hawkins, Andrew C. Scott, Walter L. Cressler Iii Oct 2015

The Rise Of Fire: Fossil Charcoal In Late Devonian Marine Shales As An Indicator Of Expanding Terrestrial Ecosystems, Fire, And Atmospheric Change, Susan M. Rimmer, Sarah J. Hawkins, Andrew C. Scott, Walter L. Cressler Iii

Earth & Space Sciences Faculty Publications

No abstract provided.


North-Central Nebraska Geology: Niobrara River Valley In Brown, Cherry, And Keya Paha Counties, R. M. Joeckel, L. M. Howard, S. T. Tucker Oct 2015

North-Central Nebraska Geology: Niobrara River Valley In Brown, Cherry, And Keya Paha Counties, R. M. Joeckel, L. M. Howard, S. T. Tucker

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Aulacoseira Stevensiae Sp. Nov. (Coscinodiscophyceae, Bacillariophyta), A New Diatom From Ho Ba Bê, Bac Kan Province, Northern Viêt Nam, D. Marie Weide Oct 2015

Aulacoseira Stevensiae Sp. Nov. (Coscinodiscophyceae, Bacillariophyta), A New Diatom From Ho Ba Bê, Bac Kan Province, Northern Viêt Nam, D. Marie Weide

Department of Earth and Atmospheric Sciences: Faculty Publications

A new species of Aulacoseira Thwaites is described from piston core samples from Ho Ba Bê in the karst region of northern Viêt Nam. Although it closely resembles Aulacoaseira subborealis (Nygaard) Denys, Muylaert & Krammer, A. stevensiae Weide sp. nov. is designated a new species based mainly on morphological differences in the spines, including invariably inclined spines that are rounded, differences in the Ringleiste, areola pattern and overall size. Aulacoseira stevensiae is present throughout a core that spans the last 500 years. It was a major component of the diatom community, but the populations have recently decreased, possibly being outcompeted …