Physical Sciences and Mathematics Commons^™

Acremonium-Endophytes Of Perennial Ryegrass (Lolium Perenne) In France, C Ravel, C Astier, F Balfourier, G Charmet

IGC Proceedings (1997-2023)

Infection with endophytic fungi (Acremonium spp.) was detected in seeds of wild populations of perennial ryegrass (Lolium perenne) collected in France by private breeding companies and INRA. In total, 262 populations were examined and 70% contained Acremonium. It is worth noticing that most populations are endophyte infected but generally endophyte infection rates per population were low. Isolation of endophyte from each infected population is under progress and had already shown that the two taxonomic groups of endophytes of perennial ryegrass are present. This work lead to a view of the distribution of Acremonium endophytes from perennial …

Gis And Genetic Diversity- Case Studies In Stylosanthes, P G. Jones, M C. Sawkins, B L. Maass, P C. Kerridge

IGC Proceedings (1997-2023)

We present a new technique for mapping the potential occurrence of wild germplasm based in climate data and show its application to six important Stylosanthes species. The method can be used to develop hypotheses as to the distribution for purposes of collection and/or in situ conservation. It can also be used to investigate genetic diversity with a species. We present some first results based in isozyme data from S. guianensis.

The Plants Database: Providing Basic Plant Information, J S. Peterson, J F. Henson, W Oaks, J T. Kartesz

IGC Proceedings (1997-2023)

The PLANTS database provides basic plant information to the United States Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS), its clients, cooperators, and the general public via the World Wide Web (Fig. 1). The foundation of PLANTS is a taxonomic backbone (checklist) of the vascular and nonvascular plants of North America (north of Mexico) and United States territories in the Caribbean and Pacific regions. Attribute data are appended to this backbone pertaining to distribution, vegetative specifications, nativity, federal and state status, crop data, growth form, growth parameters, species abstracts, and images.

Identifying Taphonomic Distribution Patterns At The Gray Fossil Site, Shawn Haugrud

Electronic Theses and Dissertations

Since the early days of the discovery of the Gray Fossil Site (GFS), meticulous efforts to preserve the spatial data were a priority. Direct surveying of fossils prior to recovery, as well as grid mapping the site, provided relative spatial data within a square meter. Such efforts meant that even fragments and microfossils, recovered during the screening operations and eventual concentrate picking, maintained some spatial data. Available spatial data are used to identify smaller deposits within the greater system, as well as non-random distribution patterns among a number of GFS taxa. Patterns are particularly pronounced in the large-bodied taxa, Teleoceras …

Sturgeon Chub Distributional Patterns And Habitat Use And Benthic Fish Assemblage Structure In Missouri River Tributaries Of South Dakota, Mitchell R. Magruder

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

Native species of the Missouri River drainage inhabiting benthic habitats dominate state and federal lists of species at risk. Sicklefin Chub Macrhybopsis meeki and Sturgeon Chub Macrhybopsis gelida are two native Missouri River benthic minnows that are currently under review for federal listing under the Endangered Species Act (ESA) due to extensive population declines and local extirpations within their native range. Substantial alterations to the Missouri River threaten Macrhybopsis spp. and other benthic fishes; however, large, less impacted tributaries in South Dakota may act as refugia for native species. The extent of Sicklefin Chub and Sturgeon Chub populations is largely …

Moving On Up: Vertical Distribution Shifts In Rocky Reef Fish Species During Climate-Driven Decline In Dissolved Oxygen From 1995 To 2009, Erin L. Meyer-Gutbrod, Li Kui, Mary Nishimoto, Linda Snook, Milton Love

Faculty Publications

Anthropogenic climate change has resulted in warming temperatures and reduced oxygen concentrations in the global oceans. Much remains unknown on the impacts of reduced oxygen concentrations on the biology and distribution of marine fishes. In the Southern California Channel Islands, visual fish surveys were conducted frequently in a manned submersible at three rocky reefs between 1995 and 2009. This area is characterized by a steep bathymetric gradient, with the surveyed sites Anacapa Passage, Footprint and Piggy Bank corresponding to depths near 50, 150 and 300 m. Poisson models were developed for each fish species observed consistently in this network of …

Distribution Of Crude Fat For A Halophyte (Suaeda Glauca) Growing In The Songnen Grassland, H. X. Sun, Ch. L. Liu, Ch. Sh. L.

IGC Proceedings (1997-2023)

No abstract provided.

Joint Spacing In The Caples Lake Granodiorite Of The Sierra Nevada Batholith In Eldorado National Forest, California: A Comparative Analysis Of Joint Sets And Data Resolution, Jimmy Wood

Theses/Capstones/Creative Projects

Joints are the most common deformation structure in the Earth’s upper crust and exert a significant influence on structural stability, landscape morphology, and fluid flow . Therefore, a greater understanding of fracture parameters (e.g., length, aperture, etc.) allows us to more accurately predict their presence, persistence, and prevalence, in the subsurface . We study the fracture spacing of two sub-orthogonal joint sets—66 NE-246 SW and 330 NW-150 SE—in the Caples Lake granodiorite of the Sierra Nevada Batholith, California. Specifically, we investigate 1) their spacing distributions with a keen interest in power-law (fractal) spacing, 2) distribution comparisons between master and cross …

An Investigation On Some Ecological Characteristics Of Ziziphus Spina Chirsti (L.) In Southern Iran, A. R. Mahmoodi, Mansour Mesdaghi, Masoume Amirkhani, E. Kargari

IGC Proceedings (1997-2023)

No abstract provided.

Distribution And Occurrence Of Uranium In Coal And Its Migration Behavior During The Coal Utilization, Wang Wenfeng, Wang Wenlong, Liu Shuangshuang, Bai Hongyang, Wang Yulong, Duan Piaopiao, Qin Kemin, Chen Yilin

Coal Geology & Exploration

Coal and uranium resources are closely related in spatial disposition as well as mineralization, and the reasonable development, utilization and pollution control of them play an essential role in the sustainable development of our national economy and society. Based on a large number of literature research and the previous results of our research group, some conclusions were drawn with regard to the distribution and occurrence of uranium in coal `and its migration in the process of coal preparation, combustion and leaching:(1) The enrichment and mineralization of uranium in coal has reflected the evolution of coal-forming tectonics:The U-rich coal in Southwest …

Species Distribution Modeling For Arid Adapted Habitat Specialists In Zion National Park, Sam Driver, Daniel R. Unger, David L. Kulhavy, Chris M. Schalk

Student Publications

The Arizona toad (Anaxyrus microscaphus) and Jones’ waxy dogbane (Cycladenia humilis var. jonesii) are habitat specialists with historical ranges in the desert southwest and specifically, Zion National Park (ZION). The machine learning method, MaxEnt, constructed species distribution models (SDMs) in ZION for the two study species at 30 m and 900 m spatial resolutions using climate, topographic, and remotely sensed data. Additionally, 900 m forecasting models were constructed to observe the shifts in suitable habitat for the years 2050 and 2070, based off two representative concentration pathway scenarios. Results indicate promising predictive power for both high …

Forming Mechanism And Classification Standard Of "Black-Soil-Type" Degraded Grassland In Yangtze And Yellow River Headwater Region Of Qinghai-Tibetan Plateau, Y. S. Ma, Q. M. Dong, S. H. Yang, J. J. Shi, L. Sheng, Y. L. Wang, X. D. Sun

IGC Proceedings (1997-2023)

No abstract provided.

Distributed Overgrazing: A Key Cause Of Grassland Degradation In Inner Mongolia, Qian Zhang, Wenjun Li, Yina Xie, Changling Li, Yanbo Li

IGC Proceedings (1997-2023)

No abstract provided.

Thirty Years Of Data Sheds Light On Plastic Pollution In The Deep Sea, Adam Warren

Scientific Communication News

No abstract provided.

Manipulation Of The Spatial Grazing Behaviour Of Livestock In Extensive Grassland Systems, Derek W. Bailey, Mitch B. Stephenson, Milton G. Thomas, Juan F. Medrano, Gonzalo Rincon

IGC Proceedings (1997-2023)

Spatial behaviour of livestock is a critical factor in grassland management. Recent and ongoing research suggests that new approaches can be used to manipulate where cattle graze. The combination of strategic supplement placement and low-stress herding can be used to target cattle grazing and potentially may be useful for managing fine fuels. A phenotype to genotype association study of cattle spatial behavior suggests that use of rugged terrain and areas far from water is inherited. Although more research is needed, selection for animals specifically adapted for mountainous terrain or extensive paddocks may be an alternative for managing grasslands in the …

Factors Influencing The Spatial Distribution Of Southern Rust In Corn, Justin Bailey

Graduate Theses and Dissertations

Southern rust caused by the fungus Puccinia polysora (Underwood) is the most economically important foliar disease in corn (Zea mays) (Linnaeus) (Cyperales: Poaceae)) for Arkansas. The objective of this work was to determine distribution of southern rust in corn and to determine factors that may control its distribution.

During the 2017 and 2018 season, seven corn fields in Arkansas were rated for southern rust. After disease confirmation, fields were marked with GPS sample point locations in a grid pattern across the entire field. Ratings for disease severity were taken below, at, and above the ear leaf at each point every …

Assessment Of The Ponderosa Woodlands In Nebraska's Wildcat Hills: Implications For Juniperus Encroachment And Management, Allie Victoria Schiltmeyer

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

Ponderosa pine (Pinus ponderosa) is a dominant tree species across western North America. Its eastern distribution includes three populations in western Nebraska. This study assesses the distribution, structure and age of ponderosa pine woodlands in one of those regions, the Wildcat Hills. The Wildcat Hills have escaped severe wildfires seen in recent decades in other ponderosa pine regions. Nevertheless, the Wildcat Hills woodlands face multiple threats including climate change, wildfire, drought, pine beetles, and invasive species. Key to these threats is the stand structure of pine woodlands, which have increased in density across much of ponderosa pine’s range. …

Sensitivity Of Mangrove Range Limits To Climate Variability, Kyle C. Cavanaugh, Michael J. Osland, Remi Bardou, Gustavo Hinojosa-Arango, Juan M. Lopez-Vivas, John D. Parker, Andre S. Rovai

United States Geological Survey: Staff Publications

Aim: Correlative distribution models have been used to identify potential climatic controls of mangrove range limits, but there is still uncertainty about the relative importance of these factors across different regions. To provide insights into the strength of climatic control of different mangrove range limits, we tested whether temporal variability in mangrove abundance increases near range limits and whether this variability is correlated with climatic factors thought to control large scale mangrove distributions.

Location: North and South America.

Time period: 1984–2011.

Major taxa studied: Avicennia germinans, Avicennia schuaeriana, Rhizophora mangle, Laguncularia racemosa.

Methods: We characterized temporal variability in the enhanced …

Dentine Oxygn Isotopes (Δ18o) As A Proxy For Odontocete Distributions And Movements., Cory J.D. Matthews, Fred J. Longstaffe, Steven H. Fergispm

Earth Sciences Publications

Spatial variation in marine oxygen isotope ratios ( δ¹⁸O) resulting from differential evaporation rates and precipitation inputs is potentially useful for characterizing marine mammal distributions and tracking movements across δ¹⁸O gradients. Dentine hydroxyapatite contains carbonate and phosphate that precipitate in oxygen isotopic equilibrium with body water, which in odontocetes closely tracks the isotopic composition of ambient water. To test whether dentine oxygen isotope composition reliably records that of ambient water and can therefore serve as a proxy for odontocete distribution and movement patterns, we measured δ¹⁸O values of dentine structural carbonate (δ^{18 …}

Small-Scale Biogeographic Patterns Of Benthic Bacterial And Ciliate Communities In The Saline Ponds Of Lake Macleod, North-Western Australia, Christopher Kavazos

Theses: Doctorates and Masters

This biogeographical thesis tests for the presence of taxa-area and distance-decay relationships, which are common among macrobionts, in prokaryotic (bacterial) and micro-eukaryotic (ciliate) communities. Microbial biogeographical patterns may be distinct because of the high abundances, diversity and dispersal capabilities of microbes, in comparison to macrobionts. The Northern Ponds of Lake MacLeod, north-western Australia, provide an ideal location to address this topic, because the ponds are effectively hydrogeomorphologically identical, other than in surface area, and biotic histories can be assumed to differ only according to distance of separation. This means that hypotheses concerning species-sorting and neutral processes on microbial assemblages can …

Global Warming And Population Responses Among Great Plains Birds, Paul A. Johnsgard

Zea E-Books Collection

Based on an analysis of 47 years (1967–2014) of Audubon Christmas Bird Counts (CBC), evidence for population changes and shifts in early winter (late December) ranges of nearly 150 species of birds in the Great Plains states is summarized, a region defined as including the Dakotas, Nebraska, Kansas, Oklahoma, and the Texas panhandle. The rationale for this study had its origins in Terry Root’s 1988 Atlas of North American Wintering Birds. Root’s landmark study provided a baseline for evaluating the nationwide winter distributions of 253 North American birds in the mid-20th century, using data from the National Audubon Society’s …

Chapter Two: Chromium Contamination And Its Risk Assessment In Complex Environmental Settings, Girish Choppala, Nanthi Bolan, Jin Hee Park

Dr Girish Choppala

Chromium reaches the soil environment through waste disposal emanating from a number of industrial activities, including coal-fired power production, electroplating, leather tanning, timber treatment, pulp production, and mineral ore and petroleum refining. Of the heavy metals, chromium (Cr) is a major pollutant, poses a great threat to flora and fauna and persists for long time. The most abundant species of Cr—Cr(III) and Cr(VI)—have very different properties. The toxicity, mobility, and bioavailability of Cr mainly depend on its speciation. In the natural environment, Cr(III) is most immobile, less soluble and stable, whereas Cr(VI) is highly mobile, soluble and bioavailable. Redox reactions …

Algal Quality Controls The Distribution, Behavior And Growth Of Algivorous Cichlids In Lake Tanganyika, Renalda Nanziga Munubi

Browse all Theses and Dissertations

The nutritional value of primary producer is dependent on the concentrations of C, N and P. These elements are the building blocks for protein, carbohydrates, lipids, nucleic acids and other biochemical compounds. The balance between the supply of dietary elements and the herbivore's demand is crucial for the growth of algivorous organisms, including fish. However, anthropogenic changes in primary producer quality due to sediments may alter the value and quantity of food in the littoral zone of Lake Tanganyika, which may affect both herbivorous near shore and pelagic fisheries. This dissertation focuses on the influence of algae food on herbivore …

The Effects Of Invasive Earthworm Species On Salamanders In The Grand Valley State University Ravine Ecosystem, Hunter J. Brunges, James Dunn

Student Summer Scholars Manuscripts

Earthworms are an invasive species that are causing ecological damage to northern forest ecosystems. The disruption to soil nutrient cycling and litter decomposition can negatively impact organisms that live within the leaf litter, such as salamanders. To test this hypothesis, we sampled earthworms within three ravines at thirty-six sites using the mustard extraction method. We surveyed salamander populations on two dates in 2015 at each site using cover boards. We also collected data on slope aspect, altitude, soil moisture, leaf litter coverage, canopy cover, and coarse woody debris at each site to determine their effects on earthworm and salamander populations. …

Quantitative Analysis Of The Polarity Reversal Pattern Of The Earth's Magnetic Field And Self-Reversing Dynamo Models, Patrick Shane Craig

Browse all Theses and Dissertations

The geologic record documents that the Earth's magnetic field has reversed 284 times over the past 160 Myr. This study uses two methods to analyze the scaling properties of the pattern of geomagnetic reversals and to analyze the scaling properties of reversals output by two mathematical self-reversing dynamo models, the Rikitake (1958) two-disk dynamo and the magnetohydrodynamic (MHD) model of Driscoll and Olson (2011). The first analysis method plots the duration versus cumulative probability for geomagnetic polarity intervals ranging between 0.01 and 35 Myr. The Kolmogorov-Smirnov statistic is used to determine the optimal minimum value of xmin at which power …

Major Elements Geochemistry Of The Breiner Baiut Ore Deposit (Gutai Mountains, Eastern Carpathians), Dan Costin

Studia UBB Geologia

The Breiner Băiuţ epithermal vein – type deposit is basically a base metal ore body with important amounts of gold and silver. The frequency distribution pattern of the major elements (Au, Ag, Pb, Zn, Cu, S) is complex in many cases, but at some mining levels it is lognormal. The correlation coefficient "r" has been calculated for six pairs of major elements. The values are positive and indicate strong correlations between these elements. The average grades values for each major element at all levels have been used to highlight the vertical variation of chemistry of the mineralization. The ore body …

Development Of Functional Indices Of Facility Occurrence Towards The Distribution Of Social Services In Lagos Island Nigeria., Augustus O. Atubi

Confluence Journal Environmental Studies (CJES), Kogi State University, Nigeria

Proper coordination of transport and public facilities provision is vital to any balanced regional development strategy. The central aim of this study, therefore, is to find out what the relationship is between access to the transport network and the provision of functional indices of facility occurrence towards the distribution of social services in Lagos Island, Nigeria. In particular it seeks to find out areas that have below or above average level of facility occurrences relative to the level of accessibility. However, a pair wise correlation matrix of the eleven (11) variables employed in the index construction was carried out. The …

Spatial Distribution Of Commercial Banks In Ilorin Metropolis, Kwara State, Nigeria, I B. Abdullahi, M A. Ijaiya, A Abdulraheem, R I. Abdulkadir, R O. Ibrahim

Confluence Journal of Environmental Studies (CJES), Kogi State University, Nigeria

The spatial distribution of banks in any geographic entity determines the level of accessibility to its services by the public. This study examined the pattern of banks distribution in Ilorin metropolis. Field survey was employed in determining the number of available commercial banks and their respective distances between each other. The spatial analysis technique such as the nearest neighbour analysis as used ascertain the degree of clustering, density and the average distance taken to access these services. The study revealed that about 96% of the total number of banks are situated in the Central Business District which exhibited a very …

Colorado River Water: Mexico's Perspective On The Ongoing Negotiations, Mario López Pérez

US-Mexico Negotiations on Improved Colorado River Management: An Update (February 19)

Presenter: Mario López, Engineering and Technical Standards Manager, National Water Commission of México

53 slides

Slides: Water Footprints: Consciousness Raising Meets Risk Management, Steve Malloch

Western Water Law, Policy and Management: Ripples, Currents, and New Channels for Inquiry (Martz Summer Conference, June 3-5)

Presenter: Steve Malloch, Senior Western Water Program Manager, National Wildlife Federation, Seattle, WA

38 slides