Digital Commons Network^™

Mercury And Cyanide Used As Indicators Of Sediment Transport In Ephemeral Washes At The Techatticup Mine And Mill Site, Nelson, Nevada (Usa), Douglas Brian Sims, Anthony Francis

International Journal of Soil, Sediment and Water

Mercury (Hg) and cyanide (CN-) are used as indicators of aquatic transport down gradient in ephemeral washes. The pattern of transport for Hg and CN- should mimic other metals (As, Cu, Cr, Pb, Ni, Ba) found in the soils. Hg and CN- were chosen to illustrate transport in surface soils because Hg and CN- are utilized in the milling process and Hg is available from the local geology. Stamp mills that utilize Hg and CN- flotation concentrate naturally occurring metals as byproducts. Soil samples collected from a wash system bisecting the mine waste site contained metal concentrations significantly above background …

Polycyclic Aromatic Hydrocarbons (Pahs) In Urban Soil: A Florida Risk Assessment Perspective, Christopher M. Teaf

International Journal of Soil, Sediment and Water

Over the past decade, polycyclic aromatic hydrocarbons (PAHs) have steadily climbed in importance on the CERCLA list of hazardous substances. Though the listing does not necessarily imply that these chemicals exhibit the greatest degree of toxicity, such recognition by ATSDR and USEPA is predicated at least in part on their demonstrated ubiquity, coupled with toxicity considerations. Regulatory agencies increasingly are under pressure to define and interpret data describing urban background levels, and to appropriately determine the relative importance of waste-producing activities and concentrations resulting from typical natural and/or human activity. Three case studies from Florida are presented that confirm the …

Identification Of Subsoil Compaction Using Electrical Conductivity And Spectral Data Across Varying Soil Moisture Regimes In Utah, Jay Murray Payne

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Subsoil compaction is a major yield limiting factor for most agricultural crops. Tillage is the most efficient method to quickly treat compacted subsoil, but it is also expensive, increases erosion, and accelerates nutrient cycling.

The use of real-time electrical conductivity (EC) and near-infrared (NIR) reflectance values to differentiate compacted areas from uncompacted areas was studied. This method has potential to reduce monetary and time investments inherent in traditional grid sampling and the resultant deep tillage of an entire field. EC and NIR reflectance are both very sensitive to spatial variability of soil attributes.

The objective of this research was to …

Solarization Effects On Chemical Properties Of Soils Under Kudu (Pueraria Montana) Invasion, Nicole Gilbert

All Theses

Solarization is an effective method for managing small areas with kudzu (Pueraria montana) invasions that may alter soil chemical properties. Conducted from 2005 to 2007 at the Clemson University Experimental Forest in Clemson, South Carolina on a Cecil clay loam (fine, kaolinitic, thermic Typic Kanhapludult), this study compares soil chemical properties under thermally-treated and non-treated plots at different depths invaded by Kudzu.
The experimental factors of treatment and depth were arranged in a factorial treatment design with 15 treatments arranged in a split plot design. The five thermal treatments were the whole plot factors which were arranged in a randomized …

Variations In Stomatal Traits Of 14 Bornean Tree Species Growing On Soils With Different Moisture Contents In Lambir Hills National Park, Whitney Logan Cannon

Department of Environmental Studies: Undergraduate Student Theses

The goal of this study was to look at variations in stomatal traits of tree species on soils with different moisture contents and fertility at Lambir Hills National Park. Stomates are important structures on the surface of leaves that mediate conduction of moisture and gassesin and out of the leaf. If stomatalt raits are important for regulation, then there should be variation in stomatal traits in regards to their soil specialization. The 14 Borneant ree speciess ampledi ncluded6 sandyl oam specialists6, clay specialistsa nd 2 generalistsfo und growing with equald istributionso n both sandyl oam and clay. Confocal microscopy was …

Mine Detonation Trailers: Stresses Induced By Wheels Below The Surface Of A Soil Road, Peter Renwick

The Journal of Conventional Weapons Destruction

This article examines the use of wheels to detonate mines buried in soil roads. Realistic pressure patterns and loading of the footprints of two types of detonation wheel were established. Solid modeling created typical tire footprints above a medium representing soil. Finite element analysis investigated stress patterns in the soil for two types of wheel at loads of both 1,800 and 5,000 kgf.

Climatically Driven Loss Of Calcium In Steppe Soil As A Sink For Atmospheric Carbon, A. G. Lapenis, G. B. Lawrence, S. W. Bailey, B. F. Aparin, Alexander I. Shiklomanov, N. A. Speranskaya, M. S. Torn, M. Calef

Faculty Publications

During the last several thousand years the semi‐arid, cold climate of the Russian steppe formed highly fertile soils rich in organic carbon and calcium (classified as Chernozems in the Russian system). Analysis of archived soil samples collected in Kemannaya Steppe Preserve in 1920, 1947, 1970, and fresh samples collected in 1998 indicated that the native steppe Chernozems, however, lost 17–28 kg m−2 of calcium in the form of carbonates in 1970–1998. Here we demonstrate that the loss of calcium was caused by fundamental shift in the steppe hydrologic balance. Previously unleached soils where precipitation was less than potential evapotranspiration are …

Categorization Of Soil Suitability To Crop Switchgrass At Mississippi, Us Using Geographic Information System, Multicriteria Analysis And Sensitivity Analysis, Eduardo Fernando Arias

Theses and Dissertations

Switchgrass (Panicum virgatum) has been widely investigated because of its notable properties as an alternative pasture grass and as an important biofuel source. The goal of this study was to determine soil suitability for Switchgrass in Mississippi. A linear weighted additive model was developed to predict site suitability. Multicriteria analysis and Sensitivity analysis were utilized to optimize the model. The model was fit using seven years of field data associated with soils characteristics collected from NRCS-USDA. The best model was selected by correlating estimated biomass yield with each model’s soils-based output for Switchgrass suitability. Pearson’s r (correlation coefficient) was the …

Understanding Your Soil Test Report, Grant E. Cardon, Jan Kotuby-Amacher, Pam Hole, Rich Koenig

Gardening

No abstract provided.

Understanding Your Soil Test Report, Grant E. Cardon, Jan Kotuby-Amacher, Pam Hole, Rich Koenig

All Current Publications

Regular soil testing helps to develop and maintain more productive soils for farming, gardening, and landscaping. The purpose of this guide is to help you understand and interpret the results from a Utah State University soil test report. Additional Utah State University Extension bulletins are available, which address solutions to specific soil problems and offer guidance on fertilizer selection and use. See “Where to obtain additional information” at the end of this guide.

Application Of Time-Lapse Ert Imaging To Watershed Characterization, Carlyle R. Miller, Partha S. Routh, Troy R. Brosten, James P. Mcnamara

Geosciences Faculty Publications and Presentations

Time-lapse electrical resistivity tomography (ERT) has many practical applications to the study of subsurface properties and processes. When inverting time-lapse ERT data, it is useful to proceed beyond straightforward inversion of data differences and take advantage of the time-lapse nature of the data. We assess various approaches for inverting and interpreting time-lapse ERT data and determine that two approaches work well. The first approach is model subtraction after separate inversion of the data from two time periods, and the second approach is to use the inverted model from a base data set as the reference model or prior information for …

Geophysical Imaging Of Watershed Subsurface Patterns And Prediction Of Soil Texture And Water Holding Capacity, H. Abdu, D. A. Robinson, M. Seyfried, Scott B. Jones

Plants, Soils, and Climate Faculty Publications

The spatial distribution of subsurface soil textural properties across the landscape is an important control on the hydrological and ecological function of a watershed. Traditional methods of mapping soils involving subjective assignment of soil boundaries are inadequate for studies requiring a quantitative assessment of the landscape and its subsurface connectivity and storage capacity. Geophysical methods such as electromagnetic induction (EMI) provide the possibility of obtaining high-resolution images across a landscape to identify subtle changes in subsurface soil patterns. In this work we show how EMI can be used to image the subsurface of a ∼38 ha watershed. We present an …

Oyster Harbour Catchment Appraisal 2007, Ron Master, South Coast Agricultural Rca Team

Resource management technical reports

No abstract provided.

Caneberry Irrigation, Brent Black, Robert Hill, Grant Cardon

All Current Publications

No abstract provided.

Determination Of Trace Elements In Siliceous Samples By Icp-Ms After Precipitation Of Silicon As Sodium Fluorosilicate, Z Arslan, Jf Tyson

Chemistry Department Faculty Publication Series

No abstract provided.

Long-Term Tillage Frequency Effects On Dryland Soil Physical And Hydraulic Properties, Andrew W. Lenssen, J. D. Jabro, U. M. Sainju, W. B. Stevens, R. G. Evans

Andrew W. Lenssen

Soil tillage is considered one of most important practices in agricultural production due to its influence on physical, chemical, and biological properties of the soil environment. The effect of a long-term tillage [no-till (NT), spring till (ST), and fall and spring till (FST)] was investigated on soil penetration resistance (PR), bulk density (BD), gravimetric water content (GWC) and saturated hydraulic conductivity (Ks) under dryland conditions. Tillage effects on these physical properties were tested after 22 years on a Dooley sandy loam (fine-loamy, mixed Typic Argiborolls) derived from glacial till parent material. The statistical design used was a randomized complete block …

Spatiotemporal Variation In Soil Moisture And Hydraulic Properties And Their Impacts On Rainfall -Runoff And Infiltration Processes, Jun Yin

UNLV Retrospective Theses & Dissertations

In arid and semi-arid regions such as in the southwestern United States, soil moisture is an essential component of desert ecosystems. Gaining better knowledge of moisture dynamics through appropriate numerical modeling will help us understand physical mechanisms that influence soil hydrologic processes in these regions. Moreover, numerical modeling of these processes is often emphasized because most desert watersheds are ungauged, and thus field observations are either not readily available or difficult to simulate. In this dissertation, three modeling studies were conducted to investigate the temporal and spatial soil moisture variation and hydraulic properties, and their effect on rainfall-runoff and infiltration …

Effects Of Elevated Carbon Dioxide On Soil Microbial Communities Of The Mojave Desert, Linh M. P Nguyen

UNLV Retrospective Theses & Dissertations

The objective of this study is to determine soil microbial community structure in the framework of increased atmospheric carbon availability associated with global change. Since arid ecosystems make up a considerable fraction of our biosphere, their response to global change will be of significance. Further, implication for plant and ecosystems productivity in arid environments may be linked to changes in diversity among microbial communities, since the cycling of essential elements in the soil is often mediated by microbes. The following are three sets of experiments designed to examine the changes in microbial diversity associated with a global change factor, an …

Heavy Metal Content In Soils Under Different Wastewater Irrigation Patterns In Chihuahua, Mexico, V. M. Maldonado, H. Q. Rubio-Arias, R. Quintana, R. A. Saucedo, Melida Gutierrez, J. A. Ortega, G. V. Nevarez

College of Natural and Applied Sciences

An area near the city of Chihuahua has been traditionally irrigated with wastewater to grow forage crops. It has been hypothesized that metal levels could be found in these soils high enough to cause potential health problems to the population. The objective of this study was to determine heavy metal concentrations in different soils due to irrigation practices. Four soil types were evaluated; a soil with a past and present history of wastewater irrigation (S1), a soil with a history of wastewater irrigation until 2003 (S2), a soil with no irrigation history (S3), and a soil similar to S1 and …

Assessing Soil Remobilisation In Catchments Using A 137 Cs-Sediment Hillslope Model, Ava D. Simms, Colin D. Woodroffe, Brian G. Jones, Henk Heijnis, Jennifer Harrison, Rob Mann

Faculty of Science - Papers (Archive)

Soil redistribution studies are important, especially in water supply catchments, because the rate at which denudation is occurring has implications for offsite water quality. However, the extent to which soil is redistributed within the landscape can be difficult to determine. This challenge can be overcome using fallout caesium-137 (¹³⁷Cs). This paper describes the rates of soil loss and remobilisation in two sub-catchments within the Sydney Basin region, namely Kembla and Kentish Creeks, which drain to the Cordeaux reservoir. The total inventories of ¹³⁷Cs in catchment soils were determined, a 137Cs-regression equation and a theoretical diffusion and migration …

Finite Element Simulation Of Mandrel Penetration In A Normally Consolidated Soil, Cholachat Rujikiatkamjorn, Ali Ghandeharioon, Buddhima Indraratna

Faculty of Engineering - Papers (Archive)

In this paper, a finite element simulation of the mandrel penetration in normally consolidated soils is presented using a commercial finite element code (ABAQUS). A coupled analysis with large-strain frictional contact is used to simulate the soil-mandrel interface during mandrel penetration. The modified Cam clay model is used to represent the soft soil. The numerical predictions are then compared with the results obtained from the large scale laboratory tests to predict the extent of the smear zone. A large scale consolidation test was conducted with the rate-controlled device used to install the mandrel. The associated excess pore pressures at various …

Non-Linear Consolidation Of Soil With Vertical And Horizontal Drainage Under Time-Dependent Loading, Xueyu Geng

Faculty of Engineering - Papers (Archive)

This paper presents a nonlinear theory for sand drain consolidation of clayey soils under time dependent loading. The solution is obtained using the method of separation of variables. Using the solutions obtained, some diagrams are prepared and the relevant consolidation behavior of soil with vertical and horizontal drainage under time-loadings is discussed. For nonlinear material properties, average degree of consolidation can be defined either in terms of settlement or in terms of effective stress. And consolidation will be slower when compared to the cases with constant material properties. And the difference depends on the external loading pressure N, and the …

Impact Of Long-Term Application Of Treated Tannery Effluents On The Emergence Of Resistance Traits In Rhizobium Sp. Isolated From Trifolium Alexandrinum, Mohd. Musheer Altaf, Farhana Masood, Abdul Malik

Turkish Journal of Biology

A total of 35 Rhizobium sp. were isolated from the root nodules of Trifolium alexandrinum (Egyptian clover) irrigated with treated tannery effluents and characterised on the basis of morphological, cultural and biochemical characteristics. Rhizospheric soils and plant parts were also analysed for metal concentrations by atomic absorption spectrophotometry. The test soil samples were contaminated with a high level of chromium and also with other heavy metals, i.e. Ni, Zn, Cu, and Cd. The heavy metal analysis of Trifolium alexandrinum plant parts revealed different accumulation of these metals in different plant parts, such as root, stem, and leaf. Trifolium alexandrinum roots …

New And Current Microbiological Tools For Ecosystem Ecologists: Towards A Goal Of Linking Structure And Function, Rebecca E. Drenovsky, Kevin P. Ferris, Katharine M. Batten, Krassimira Hristova

Biology

Interest in the relationships between soil microbial communities and ecosystem functions is growing with increasing recognition of the key roles microorganisms play in a variety of ecosystems. With a wealth of microbial methods now available, selecting the most appropriate method can be daunting, especially to those new to the field of microbial ecology. In this review, we highlight those methods currently used and most applicable to ecological studies, including assays to study various aspects of the carbon and nitrogen cycles (e.g., pool dilution, acetylene reduction, enzyme analyses, among others), methods to assess microbial community composition (e.g., phospholipid fatty acid analysis …

Soil Temperatures During Autumn Prescribed Burning: Implications For The Germination Of Fire Responsive Species?, Trent D. Penman, A L. Towerton

Faculty of Science - Papers (Archive)

Prescribed fire is a widely applied management tool in native forests. There have been concerns raised about the ecological impacts of prescribed fire on native flora. One aspect of the debate is the extent towhich prescribed fire heats the soil to levels reported to trigger germination in the soil seed banks.We used Thermochrons to test soil temperatures at 2 and 5 cm in prescribed burns in dry sclerophyll forests. Soil temperatures during the burns were generally low (<40◦C) with less than 5% of sites being exposed to temperatures necessary for the germination of fire-dependent shrub species. High temperatures were associated with high fuel consumption and large woody debris. This information suggests that prescribed fires, carried out according to standard practices, in these forests are unlikely to trigger germination in the majority of the soil-stored seed banks. If ecological burns in these forests are aimed at promoting populations of senescing obligate seeder species, they need to be hotter than standard practice if they are to achieve their objectives, although we acknowledge that there are inherent risks associated with hotter burns.

Germination Responses Of A Dry Sclerophyll Forest Soil-Stored Seedbank To Fire Related Cues, Trent D. Penman, D Binns, R Allen, R Shiels, S Plummer

Faculty of Science - Papers (Archive)

Fire is an integral component of many ecosystems worldwide. Many plant species require fire-related cues, primarily heat and smoke, to trigger germination. Despite the importance of this process, the responses of many Australian species to these cues are unknown. Without this knowledge fire management strategies may be developed that are inappropriate for individual species and vegetation communities. In this study we examined the responses of a dry sclerophyll forest seed bank to heat and smoke germination cues. Analysis was possible for 48 taxa within the soil seedbank with 34 of these showing a response to one or both of the …

Qushion: Earthquake Protection By Rubber-Soil Mixtures, Hing H. Tsang, M Neaz Sheikh, S H. Lo, Nelson Lam

Faculty of Engineering - Papers (Archive)

This paper presents a promising earthquake protection method by placing rubber-soil mixtures (RSM) around the foundation of structures for absorbing seismic energy and exerting a function similar to that of an earthQuake cUSHION, named hereafter as "QUSHION". The validity of the method has been demonstrated by numerical simulations. A parametric study was carried out to evaluate the effectiveness and robustness of this method. The use of scrap tires as the rubber material can provide an alternative way of consuming huge stockpiles of scrap tires from all over the world. Moreover, the low cost of this proposed seismic isolation methods can …

Laterally Loaded Rigid Piles In Cohesionless Soil, Wei-Dong Guo

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, limiting force profile for laterally loaded rigid piles in sand and is differentiated from the on-pile force profile, from which elastic-plastic solutions are established and presented in explicity expressioins. Nonlinear responses of the piles are characterized by slip depths mobilized from mudline and the pile-tip. At the states of tip-yield and rotation point yield, expressions for some critical depths are developed, which allow the on-pile force profiles to be constructed. The solutions and the expressions are developed concerning a constant subgrade modulus (k) and a linearly incresing modulus with depth (Gibson k), respectively. capitalized on three measurable …

Lead Concentration Of Soils In Sorby Hills Area Of Proposed M2 Irrigation Area, East Kimberley, Edward (Ted) Arnold Griffin, Noel R. Schoknecht, Ross Brennan, Jane Speijers, Dave Allen, Mike Freeman

Resource management technical reports

No abstract provided.

Shifts In The Magnitude And Partitioning Of Atmospheric Versus Aquatic Carbon Export In Response To Changing Climatic Conditions, Andrew P. Rams

Digitized Theses

The average annual temperature measured at the Turkey Lakes Watershed has increased significantly (p=0.004) over the past 27 years. The effects of increasing annual temperatures and changing precipitation patterns on the export of carbon (C) from forests within this region are not fully understood. The aim of this thesis was to determine whether changes in meteorological conditions have caused changes in the magnitude and partitioning of atmospheric vs. aquatic C export form a forested catchment in the Turkey Lakes Watershed during the growing seasons (May 1 to October 31) over a five year period (2003 to 2007). Soil samples were …