Soil Science Commons^™

Audit Of Wa Agricultural Lime Quality 2013, Chris Gazey

Bulletins 4000 -

Applying agricultural lime is the most economical way of ameliorating low soil pH in broadscale agriculture in Western Australia (WA). In WA, agricultural lime is usually limesand from coastal sand dunes, crushed limestone from coastal deposits or crushed dolomitic lime (usually marketed as dolomite) from old lake and inland drainage systems. Other sources are Cretaceous chalk and lake bed marls.

WA agriculture is well serviced by lime suppliers, although the quality of lime varies markedly around the State, and cost does not always reflect quality as measured by neutralising value and fineness. Neutralising value and particle size distribution (fineness) are …

Establishment Guide For Sub-Tropical Grasses : Key Steps To Success, Geoff Allan Moore, Ronald J. Yates, Phil Barrett-Lennard, Phil Nichols, Brad Wintle, John Titterington, Chris Loo

Bulletins 4000 -

Sub-tropical perennial grasses are now widely sown in the Northern Agricultural region (NAR) and on the south coast of Western Australia (WA). Since 2000, more than 50 000 ha have been sown to perennial grasses in the NAR and about 150 000 ha on the south coast, mainly kikuyu.

Landslides Of Nebraska, Duane A. Eversoll

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Activated Carbon Preconditioning To Reduce Contaminant Leaching In Cement-Based Stabilization Of Soils, Renee Elizabeth Crane

Masters Theses

Powdered activated carbon (PAC) is often added with cement to enhance the stabilization and solidification (S/S) of materials contaminated with organic compounds. Adsorption of organic contaminants onto PAC can reduce leaching of organic contaminants. Simultaneous addition of PAC and cement reduces soil handling costs, but cement hydration reactions coat PAC with Ca(OH)2 before contaminants can be adsorbed onto PAC. Laboratory studies were done on four aged, contaminated soils from manufactured gas plant sites to compare the performance of S/S treatment with simultaneous addition of PAC and cement vs. cement addition after preconditioning with PAC to enhance contaminant adsorption. Performance was …

Microbial Ecology, Nitrogen, And Nitrous Oxide Trends In Marginal Soils Used For Cellulosic Biofuel Production In Eastern Nebraska, Carla M. Ahlschwede

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

There is a growing demand for diverse biofuels in the United States. Potential feedstocks for cellulosic ethanol include corn (Zea mays, L.) stover and switchgrass (Panicum virgatum, L). Lands used to provide for corn production can provide some cellulosic feedstock through corn stover, but crop residue removal can have negative impacts on soil quality. Furthermore, arable land must supply both fuel and food. To meet both demands, lands considered marginal for row-crop production will likely be used to produce dedicated bioenergy crops such as switchgrass. Marginal lands are typically placed in conservation programs because they are prone …

Accelerated Thermokarst Formation In The Mcmurdo Dry Valleys, Antarctica, Joseph S. Levy, Andrew G. Fountain, James L. Dickson, James W. Head, Marianne Okal, David R. Marchant, Jaclyn Watters

Geology Faculty Publications and Presentations

Thermokarst is a land surface lowered and disrupted by melting ground ice. Thermokarst is a major driver of landscape change in the Arctic, but has been considered to be a minor process in Antarctica. Here, we use ground-based and airborne LiDAR coupled with timelapse imaging and meteorological data to show that 1) thermokarst formation has accelerated in Garwood Valley, Antarctica; 2) the rate of thermokarst erosion is presently,10 times the average Holocene rate; and 3) the increased rate of thermokarst formation is driven most strongly by increasing insolation and sediment/albedo feedbacks. This suggests that sediment enhancement of insolation-driven melting may …

Water Track Modification Of Soil Ecosystems In The Lake Hoare Basin, Taylor Valley, Antarctica, Joseph S. Levy, Andrew G. Fountain, Michael N. Gooseff, John E. Barrett, Robert Vantreese, Kathleen A. Welch, W. Berry Lyons, Uffe N. Nielsen, Diana H. Wall

Geology Faculty Publications and Presentations

Water tracks are zones of high soil moisture that route shallow groundwater down-slope, through the active layer and above the ice table. A water track in Taylor Valley, McMurdo Dry Valleys, was analysed for surface hydrogeological, geochemical, and biological characteristics in order to test the hypothesis that water tracks provide spatial structure to Antarctic soil ecosystems by changing the physical conditions in the soil environment within the water tracks from those outside the water tracks. The presence of the water track significantly affected the distribution of biotic and abiotic ecosystem parameters: increasing soil moisture, soil salinity, and soil organic matter …

Climate Change And Plant Demography In The Sagebrush Steppe, Aldo Compagnoni

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.

Will Hubbard Brook Soils Be A Source Or Sink Of Carbon In A Changing Climate?, Chris E. Johnson

Civil and Environmental Engineering - All Scholarship

No abstract provided.

Soil Peels: Their Preparation And Presentation, Tim D. Overheu

All other publications

Soil peels are an exciting and inexpensive technique for collecting an exact reproduction of soil profiles. They are an excellent product for displays and soil extension activities. Introduced in the mid-1960s, the soil peel (lackfilm) technique was initially developed using a flexible glue product in combination with a cloth base, and was used to preserve soil stratigraphy at geo-archaeological excavations (Voight & Gittins 1977). The method described in this update introduces refinements to the technique for heavy and consolidated clay or duplex soils in Western Australia. Applying and removingtechnique was initially developed using a flexible glue product in combination with …

Responses Of Soil Respiration And Its Temperature/Moisture Sensitivity To Precipitation In Three Subtropical Forests In Southern China, H. Jiang, Qi Deng, Guoyi Zhou, Dafeng Hui, Deqiang Zhang, S. Liu, Guowei Chu, J. Li

Biology Faculty Research

Both long-term observation data and model simulations suggest an increasing chance of serious drought in the dry season and extreme flood in the wet season in southern China, yet little is known about how changes in precipitation pattern will affect soil respiration in the region. We conducted a field experiment to study the responses of soil respiration to precipitation manipulations – precipitation exclusion to mimic drought, double precipitation to simulate flood, and ambient precipitation as control (abbr. EP, DP and AP, respectively) – in three subtropical forests in southern China. The three forest sites include Masson pine forest (PF), coniferous …

Lower San Luis Obispo Creek Stewardship Plan, Raven Lukehart, Daniel Bohlman

Natural Resources Management and Environmental Sciences

No abstract provided.

Decomposition And Nutrient Release Of Different Cover Crops In Organic Farm Systems, Jianru Shi

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

Cover crops act as green manure adding organic matter to agricultural-soils. For legume green manures to be an effective nitrogen (N) source for organic farming systems, their N release must be in synchrony with crop N demand. The objectives of this study were 1) determine the decomposition rates of three common cover crops (white clover, (Trifolium repens,L ) red clover (Trifolium pratense L.) and soybean (Glycine max L) in order to determine when most N was released and its synchrony with subsequent corn crop uptake; 2) we focused on the effect of cover crops on soil …

Pushing The Envelope? Maize Production Intensification And The Role Of Cattle Manure In Recovery Of Degraded Soils In Smallholder Farming Areas Of Zimbabwe, Leonard Rusinamhodzi, Marc Corbeels, Shamie Zingore, Justice Nyamangara, Ken E. Giller

All Peer-Reviewed Publications

Soil fertility decline is a major constraint to crop productivity on smallholder farms in Africa. The objective of this study was to evaluate the long-term (up to nine years) impacts of nutrient management strategies and their local feasibility on crop productivity, soil fertility status and rainfall infiltration on two contrasting soil types and different prior management regimes in Murehwa, Zimbabwe. The nutrient management strategies employed in the study were: a control with no fertiliser, amendments of 100kg Nha-1, 100kg N+lime, three rates of manure application (5, 15 and 25tha-1) in combination with 100kg Nha-1, and three rates of P fertiliser …

Mechanisms Of Nutrient Limitation And Nutrient Acquisition In Managed And Unmanaged Forest Ecosystems, Matthew A. Vadeboncoeur

Doctoral Dissertations

Understanding the interactions between global change, human and natural disturbances, and other factors on biogeochemical processes in forests is necessary to ensure the sustainability of forest management. Here I report the results of several investigations into nutrient acquisition processes in the forests of New Hampshire. I begin with a meta-analysis of fertilization studies showing that phosphorus (P) and calcium (Ca) as well as nitrogen (N) may limit primary production in deciduous forests of the region. Because these limiting nutrients are all removed from the ecosystem when trees are harvested, I compared nutrient budgets under a range of harvesting scenarios with …

Variability In The Hydraulic Conductivity Of A Test Pad Liner System Using Different Testing Techniques, Matthew Jonathan Nanak

Graduate Theses and Dissertations

Historic methods (the time lag approach, the velocity approach, and the Z-t approach), utilized to reduce two stage borehole test data, were evaluated. Two of the historic methods provided viable results and were used for this research project. Additionally, these two methods are recommended for reducing two stage borehole test data in the future.

Flexible wall permeameter and soil index laboratory testing were conducted on the soil used to construct three environmentally controlled compacted clay liners (test pads) to develop a zone of acceptance (placement window). Using the results from the laboratory testing, two acceptance criterions were evaluated, while one …

Biodiesel Transesterification Byproducts As Soil Amendments, Solomon Parker

Graduate Theses and Dissertations

For every ten kilograms of biodiesel that is produced from the transesterification of vegetable oil, approximately 1 kg of glycerol is produced as a byproduct. Also known as glycerin, it is a chemical used in many products including cosmetics, foods, and desiccants. However, the crude glycerol created during biodiesel production is tainted with potassium hydroxide and methanol making it unsuitable for commercial use without costly refinement. With increase in production of biodiesel driven by rising fuel prices, the market has become glutted with glycerol and it is on the threshold of becoming a waste product. Common methods for disposing glycerol …

Subsurface Stratigraphy And Characterization Of Mississippian (Osagean To Meramecian) Carbonate Reservoirs Of The Northern Anadarko Shelf, North-Central Oklahoma, Brett Robert Wittman

Graduate Theses and Dissertations

Mississippian carbonate strata of the midcontinent contain prolific oil and gas reservoirs. Production from these carbonates has been primarily from two reservoir types, the Mississippi "chat" and recently denser chert-rich mudstone intervals. The"chat" interval is a high porosity chert residuum associated with the both the Osagean and basal Pennsylvanian unconformity. The distribution of the "chat" reservoir is discontinuous and heterogeneous. Recent horizontal drilling successes have reinvigorated academic and industry interest in the Lower Mississippian. Much of the activity is now targeting lower porosity, cherty, mudstone intervals of the Reeds Spring and Cowley Formations, which were previously considered to be non-economic. …

Initial Elastic Modulus Degradation Using Pressuremeter And Standard Penetration Test Results At Two Sites, Dustin Robbins

UNLV Theses, Dissertations, Professional Papers, and Capstones

In-situ testing was performed at two sites consisting of pre-bored pressuremeter testing, seismic surface wave testing to develop a shear wave velocity profile, and Standard Penetration testing during the soil boring phase in order to evaluate the feasibility of using large shallow foundations for a project. This study focuses on a comparison of the in-situ direct measurements of soil stiffness obtained from this testing program. The small strain modulus obtained from the seismic surface wave test results is compared to the intermediate strain modulus obtained from both the initial loading pressuremeter modulus and reload pressuremeter modulus. The modulus calculated from …

Soil Moisture Recognition And The Spatial Distribution Of Storm Activity In The Mojave Desert Using High-Resolution Aster And Modis Imagery For Thermophysical Mapping, Russell J. Skuse

UNLV Theses, Dissertations, Professional Papers, and Capstones

Climate models suggest that the Mojave Desert ecoregion is vulnerable to becoming drier in the future, and as the human population grows and development increases, environmental stresses will likely increase. Determining the spatial distribution and variation of soil moisture on a regional scale is an essential component to climate change, hydrologic, and habitat analyses. Soil permeability and sediment stability are characteristics that have been shown to be measurable from remote sensing observations. The primary objective of this project is to map the mechanical composition of the surface materials in the Mojave Desert ecoregion with implications for soil permeability, sediment stability, …