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Groundwater Contamination At Coal Ash Deposit Sites In Kentucky, Brandon Rose 2018 Murray State University

Groundwater Contamination At Coal Ash Deposit Sites In Kentucky, Brandon Rose

Scholars Week

No abstract provided.


Kentucky Flood And Flash Flood Comparison Of 1996 And 2017 Using Gis, Harrison Kelly 2018 Murray State University

Kentucky Flood And Flash Flood Comparison Of 1996 And 2017 Using Gis, Harrison Kelly

Scholars Week

No abstract provided.


Postseismic Restoration Of The Ecological Environment In The Wenchuan Region Using Satellite Data, Zhibin Huang, Min Xu, Wei Chen, Xiaojuan Lin, Chunxiang Cao, Ramesh Singh 2018 Chinese Academy of Sciences

Postseismic Restoration Of The Ecological Environment In The Wenchuan Region Using Satellite Data, Zhibin Huang, Min Xu, Wei Chen, Xiaojuan Lin, Chunxiang Cao, Ramesh Singh

Mathematics, Physics, and Computer Science Faculty Articles and Research

Using Landsat remote-sensing data combined with geological information extracted from ALOS and Sentinel-1A radar data, the ecological environment was evaluated in the years 2007, 2008, 2013, and 2017 through gray correlation analysis on the basis of the construction of the pressure-state-response model. The main objective of this research was to assess the ecological environment changes in Wenchuan County before and after the earthquake, and to provide reference for future social development and policy implementation. The grading map of the ecological environment was obtained for every year, and the ecological restoration status of Wenchuan County after the earthquake was evaluated. The ...


Microbial Community Structure And Functions Differ Between Native And Novel (Exotic-Dominated) Grassland Ecosystems In An 8-Year Experiment, Aleksandra Checinska Sielaff, Racheal N. Upton, Kirsten S. Hofmockel, Xia Xu, H. Wayne Polley, Brian J. Wilsey 2018 Iowa State University

Microbial Community Structure And Functions Differ Between Native And Novel (Exotic-Dominated) Grassland Ecosystems In An 8-Year Experiment, Aleksandra Checinska Sielaff, Racheal N. Upton, Kirsten S. Hofmockel, Xia Xu, H. Wayne Polley, Brian J. Wilsey

Ecology, Evolution and Organismal Biology Publications

A Grasslands dominated by non-native (exotic) spe- cies have replaced purely native-dominated areas in many parts of the world forming ‘novel’ ecosystems. Altered precipitation patterns are predicted to exacerbate this trend. It is still poorly understood how soil microbial communities and their functions differ between high diversity native- and low diversity exotic-dominated sites and how altered precipitation will impact this difference.

Methods We sampled 64 experimental grassland plots in central Texas with plant species mixtures of either all native or all exotic species; half with summer irrigation. We tested how native vs. exotic plant species mixtures and summer irrigation affected ...


Groundwater Recharge Response To Reduced Irrigation Pumping In Western Nebraska, Justin Philip Gibson 2018 University of Nebraska-Lincoln

Groundwater Recharge Response To Reduced Irrigation Pumping In Western Nebraska, Justin Philip Gibson

Dissertations & Theses in Natural Resources

Given current and continued investment in irrigation scheduling technologies, a need exists to better estimate the longevity and magnitude of water savings at watershed level to avoid the paradox of irrigation efficiency. This paradox occurs within a watershed as not all irrigation inefficiencies lead to the system losing water. For example, irrigation pumping rates in excess of crop water demand may lead to enhanced groundwater recharge or surface runoff that migrates to a stream. Thus, increases in efficiency may not lead to similar magnitudes of water savings. I hypothesize that water savings longevities are short given previous work demonstrating rapid ...


Perennial Biomass Crop Establishment, Community Characteristics, And Productivity In The Upper Us Midwest: Effects Of Cropping Systems Seed Mixtures And Biochar Applications, Catherine L. Bonin, Rivka B. Fidel, Chumki Banik, David A. Laird, Robert Mitchell, Emily A. Heaton 2018 Iowa State University

Perennial Biomass Crop Establishment, Community Characteristics, And Productivity In The Upper Us Midwest: Effects Of Cropping Systems Seed Mixtures And Biochar Applications, Catherine L. Bonin, Rivka B. Fidel, Chumki Banik, David A. Laird, Robert Mitchell, Emily A. Heaton

Agronomy Publications

Native perennial plants have potential as bioenergy feedstocks, but their use is currently limited by relatively long establishment times and low biomass yields. Some research suggests that incorporating plant species diversity and applying biochar as a soil amendment might alleviate these limitations by creating a more resilient crop and soil system. The objective of this research was to investigate how 1) seeded plant diversity and 2) biochar soil amendments interact to affect the establishment, yield, and plant species composition of biomass cropping systems during the first four years of growth on productive soils. We measured species emergence, cover, peak and ...


Examining Patterns In Nest Predation Using Artificial Nests, Victoria L. Simonsen 2018 University of Nebraska-Lincoln

Examining Patterns In Nest Predation Using Artificial Nests, Victoria L. Simonsen

Dissertations & Theses in Natural Resources

The use of artificial nests to study the predation of avian nests has faced disregard by ecologists due to inconsistencies found between the survival rates of real and artificial nests across studies and reviews. The negative perception of artificial nests providing an inconsistent assessment of survival has thus fostered the perception that artificial nests are a secondary option to be used to overcome logistical hurdles associated with achieving sufficient sample sizes in systems where study species are rare or elusive, or as merely a preliminary method to study predation across gradients. We argue that the greatest mistake ecologists have made ...


Turning Grass Into Cash With Small Ruminants, Kenneth Andries 2018 Kentucky State University

Turning Grass Into Cash With Small Ruminants, Kenneth Andries

Kentucky Grazing Conference

As agriculture continues to change, it is important to consider sustainability before starting or expanding any enterprise. One critical factor in any animal agriculture enterprise is controlling feeding costs. Most research indicates feeding is the largest expenses in any livestock enterprise. However, nutrition is critical to overall productivity and the income of the enterprise. Because of this, producers need to find ways to improve nutrient availability while minimizing costs to optimize production and profitability for their livestock enterprise.


Grazing Dairies: Challenges And Opportunities, Howard Straub III 2018 Michigan State University

Grazing Dairies: Challenges And Opportunities, Howard Straub Iii

Kentucky Grazing Conference

No abstract provided.


Considerations For Making A Profit With Stocker Cattle, Jeff Lehmkuhler 2018 University of Kentucky

Considerations For Making A Profit With Stocker Cattle, Jeff Lehmkuhler

Kentucky Grazing Conference

The southeast is home to more than 7.3 million beef cows (USDA 2018). At an estimated 80% weaning rate and 20% heifer retention, the southeast region would be expected to produce more than 4.6 million feeder calves that would go to market in 2018. The cow-calf industry in the region provides an opportunity for the stocker and backgrounding operations to co-exist. Much of the land in the region is best suited for forage and pasture production, which at the current moment, provides a low cost feed for adding pounds to light weight feeder cattle. Yet, the stocker and ...


Measuring Profitability In Grazing Operations, Kenneth H. Burdine 2018 University of Kentucky

Measuring Profitability In Grazing Operations, Kenneth H. Burdine

Kentucky Grazing Conference

When producers make investments in extending their grazing season, they do so in order to obtain an economic benefit. These benefits usually include a reduction in the number of days that stored feed (typically hay) is fed, an increase in carry capacity or stocking rate, or an increase in production level (rates of gain, weaning weights, etc). While all of these are potential benefits of improved grazing systems, a reduction in winter feeding days is often the simplest way to start. When the grazing season is extended, winter feeding days are reduced, and this cost savings can be weighed against ...


Foreword And Conference Information [2018], S. Ray Smith, Christopher D. Teutsch 2018 University of Kentucky

Foreword And Conference Information [2018], S. Ray Smith, Christopher D. Teutsch

Kentucky Grazing Conference

No abstract provided.


The Cyrilka Cave—The Longest Crevice-Type Cave In Czechia: Structural Controls, Genesis, And Age, Jan Lenart, Martin Kašing, Petr Tábořík, Natalia Piotrowska, Jacek Pawlyta 2018 University of Ostrava

The Cyrilka Cave—The Longest Crevice-Type Cave In Czechia: Structural Controls, Genesis, And Age, Jan Lenart, Martin Kašing, Petr Tábořík, Natalia Piotrowska, Jacek Pawlyta

International Journal of Speleology

The Cyrilka Cave is the second longest pseudokarst cave and the longest crevice-type cave in Czechia. Developed within the headscarp area of a deep-seated landslide, the cave became a focus of scientific research in recent years when new passages were discovered. Structural analysis provided a general tectonic plan of the cave, as well as more detailed data on geometry and kinematics of the relaxed rock massif. The primary structure of NNE- to ENE-striking bedding is broken by a system of NNE-striking fissures interconnected by two continuous ENE-striking dextral fracture zones. Abundant signs of recent sinistral strike-slips within the rock massif ...


A Sub-Millennial Sediment Record Of Ice-Stream Retreat And Meltwater Storage In The Baltic Ice Lake During The Bølling-Allerød Interstadial, April Lynn Kelly, Sandra Passchier 2018 Montclair State University

A Sub-Millennial Sediment Record Of Ice-Stream Retreat And Meltwater Storage In The Baltic Ice Lake During The Bølling-Allerød Interstadial, April Lynn Kelly, Sandra Passchier

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The rapid retreat of the Baltic Ice Stream and the development of the Baltic Ice Lake is assessed using data from sediment cores retrieved from three sub-basins in the southern Baltic Sea. Hydraulic piston coring by the International Ocean Discovery Program (IODP) recovered for the first time intact glacial lake sequences overlying diamictons and other ice-contact deposits at Sites M0063, M0064 and M0065. Based on the particle size and bulk sediment chemical composition the glacial lake sediments were subdivided into a proximal and a distal varve sequence. The origin of a dark, lithologically distinct horizon between the proximal and distal ...


Theory On Thermodynamic Constraints To Biogeochemical And Metabolic Diversity, Jordan Okie, Everett Shock 2018 Arizona State University

Theory On Thermodynamic Constraints To Biogeochemical And Metabolic Diversity, Jordan Okie, Everett Shock

Annual Symposium on Biomathematics and Ecology: Education and Research

No abstract provided.


P-T-X Constraints On Ilmenite Unit Cell And Relationship To Kimberlitic And Non-Kimberlitic Sources, Mitchell R. Galarneau 2018 The University of Western Ontario

P-T-X Constraints On Ilmenite Unit Cell And Relationship To Kimberlitic And Non-Kimberlitic Sources, Mitchell R. Galarneau

Electronic Thesis and Dissertation Repository

This research investigates the mineral ilmenite, focusing on the relationship between crystal structure and geochemical and/or pressure data. Ilmenites were obtained from diamond-rich and diamond-poor kimberlites and non-kimberlitic localities, to discriminate between these populations. Crystallographic results showed a delineation between kimberlitic and non-kimberlitic ilmenites at a c-axis value of 14.02 (±0.01) Å. Adding geochemistry and pressure enhances the separation of kimberlitic and non-kimberlitic samples; however, this isn’t the case for diamond-rich versus diamond-poor kimberlites, even with three-dimensional and cluster analyses. A subset of kimberlitic ilmenites (manganese rich) were found with c-axis values and geochemical concentrations similar ...


On Biospeleothems From A Venezuelan Tepui Cave: U-Th Dating, Growth Rates, And Morphology, Joyce Lundberg, Charles Brewer-Carías, Donald A. McFarlane 2018 Carleton University

On Biospeleothems From A Venezuelan Tepui Cave: U-Th Dating, Growth Rates, And Morphology, Joyce Lundberg, Charles Brewer-Carías, Donald A. Mcfarlane

International Journal of Speleology

Seven silica biospeleothems from Cueva Charles Brewer, Chimantá Plateau, Venezuela have been successfully U-Th dated despite very low U and high detrital Th concentrations. Growth rates are low, between ~100 to ~800 µm/ka, and are greater closer to water level. Dates in unaltered material are in good stratigraphic order, but secondary silicification may compromise the U-Th system, yielding unreliable sequences of ages. Detritally-enriched layers correlate with global climate cycles of the Late Quaternary, in particular the cooler, drier phases of MIS 5d, 5a, and 4. SEM studies indicate that the peloidal material is made up of silica nano-particles assembled ...


Clustering Data Of Mixed Categorical And Numerical Type With Unsupervised Feature Learning, Dao Lam, Mingzhen Wei, Donald C. Wunsch 2018 Missouri University of Science and Technology

Clustering Data Of Mixed Categorical And Numerical Type With Unsupervised Feature Learning, Dao Lam, Mingzhen Wei, Donald C. Wunsch

Donald C. Wunsch

Mixed-type categorical and numerical data are a challenge in many applications. This general area of mixed-type data is among the frontier areas, where computational intelligence approaches are often brittle compared with the capabilities of living creatures. In this paper, unsupervised feature learning (UFL) is applied to the mixed-type data to achieve a sparse representation, which makes it easier for clustering algorithms to separate the data. Unlike other UFL methods that work with homogeneous data, such as image and video data, the presented UFL works with the mixed-type data using fuzzy adaptive resonance theory (ART). UFL with fuzzy ART (UFLA) obtains ...


Spatial Structuring Of Cellulase Gene Abundance And Activity In Soil, Jinlyung Choi, Elizabeth Bach, Jaejin Lee, Jared Flater, Shane Dooley, Adina Howe, Kirsten S. Hofmockel 2018 Iowa State University

Spatial Structuring Of Cellulase Gene Abundance And Activity In Soil, Jinlyung Choi, Elizabeth Bach, Jaejin Lee, Jared Flater, Shane Dooley, Adina Howe, Kirsten S. Hofmockel

Agricultural and Biosystems Engineering Publications

Microbial mechanisms controlling cellulose degradation in soil habitats remains a critical knowledge gap in understanding and modeling terrestrial carbon-cycling. We investigated land management and soil micro-habitat influences on soil bacterial communities and distribution of cellulose-degrading enzyme genes in three bioenergy cropping systems (corn, prairie, and fertilized prairie). Within the soil, aggregates have been examined as potential micro- habitats with specific characteristics influencing resource partitioning and regulation, thus we also investigated genes associated with cellulose degradation within soil aggregate fractions from the fertilized prairie system. Soil bacterial communities and carbon-cycling gene presence varied across land management and soil microhabitats. Examination of ...


Improving International Development Evaluation Through Geospatial Data And Analysis, Malte Lech, Juha Ilari Uitto, Sven Harten, Geeta Batra, Anupam Anand 2018 German Institute for Development Evaluation, DEval

Improving International Development Evaluation Through Geospatial Data And Analysis, Malte Lech, Juha Ilari Uitto, Sven Harten, Geeta Batra, Anupam Anand

International Journal of Geospatial and Environmental Research

Increasing availability of new types of data strengthens geospatial research in different scientific fields and opens up opportunities to better measure results and evaluate the impacts of development interventions. This article presents examples where geospatial approaches have been applied in evaluations and thus demonstrate the potential use in informing policy design through scientifically sound evidence as well as learning.

The authors illustrate innovative ways of employing geospatial data and analysis in impact evaluations of international development cooperation. These interventions are concerned with topics such as biodiversity conservation, land degradation, sustainable use of natural resources, and disaster risk management. Recent methodological ...


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