Soil Science Commons^™

The Influence Of Hydrogeomorphology, Soil Redox Conditions, And Salinity On The Spatial Zoning Of Saltgrass, Salt Rush, And Cattails In Scotts Creek Marsh, Swanton Pacific Ranch, Ca, Mark D. Gormley

Master's Theses

Scotts Creek Marsh (SCM) is a small coastal wetland ecosystem in Davenport, CA. The vegetation of SCM is dominated by three halophytic zones comprised of saltgrass, salt rush, cattails. The objectives of the study were (i) to investigate the variables that influence the zoning of the three dominant halophyte communities in SCM and (ii) to the test the effectiveness of Indicator of Reduction in Soil (IRIS) tubes to indicate the reduction of S. The study examined the following parameters from April 6 to July 21, 2013: (i) the HGM of Scotts Creek Marsh, (ii) soil oxidation and reduction (redox) conditions, …

Methylmercury Fate In The Hypersaline Environment Of The Great Salt Lake: A Critical Review Of Current Knowledge, Danielle Barandiaran

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Methylmercury (MeHg) is a highly potent neurotoxic form of the environmental pollutant Mercury (Hg). The processes that are responsible for the conversion of Hg to MeHg are known to be both biotic and abiotic in freshwater systems. Although MeHg contamination is well documented in Great Salt Lake (GSL), the conversion of Hg into MeHg is not well-understood in saline environments much less in hypersaline waters such as GSL. The GSL is a broad, shallow high altitude (1280 m above sea level) lake that is exposed to large amounts of ultraviolet radiation and evaporation, which lead to great volatilization losses of …

Integrated Soil Fertility Management: Aggregate Carbon And Nitrogen Stabilization In Differently Textured Tropical Soils, R. M. Gentile, B. Vanlauwe, J. Six

All Peer-Reviewed Publications

Soil organic matter is important to improve and sustain soil fertility in tropical agroecosystems. The combined use of organic residue and fertilizer inputs is advocated for its positive effects on short-term nutrient supply, but the effect of the integrated use on long-term stabilization of soil organic C and N is still unclear. We conducted a 1.5-y soil incubation experiment with maize (Zea mays) residue and urea fertilizer to examine the stabilization of C and N in four Sub-Saharan African soils differing in texture (sand, sandy loam, clay loam, and clay). The inputs were enriched with 13C and 15N in a …

Biome Q10 And Dryness, Chuixiang Yi, Daniel Ricciuto, George Hendrey

Publications and Research

Temperature sensitivity of soil respiration (Q₁₀) is a critical parameter in carbon cycle models with important implications for climate-carbon feedbacks in the 21st century. The common assumption of a constant Q₁₀, usually with a value of 2.0, was shown to be invalid by a previous model-data fusion study that reported biome-specific values of this parameter. We extend the previous analysis by demonstrating that these biome-level values of Q₁₀ also are a function of dryness (R² = 0.54). When tundra and cultivated lands are excluded, the correlation is much stronger (R² = 0.92). Therefore …

Improving The Efficiency Of Fall Applied N With Cover Crops, Corey Lacey

Theses and Dissertations

Nitrate loss studies in Midwestern tile-drained fields have found that fall applied nitrogen (N) resulted in elevated nitrate concentrations in tile water during both the corn and soybean year of a 2 year rotation. The effectiveness of cover crops to reduce nitrate leaching when N is spring applied has been well demonstrated, however there is a dearth of knowledge on the ability of cover crops to reduce nitrate leaching in a system where N is fall applied. Thus, the objectives of this research were to (i) investigate the efficacy of winter cover crops to reduce nitrate leaching from fall applied …

2014 Weed Control Recommendations For Kentucky Grain Crops, Jonathan D. Green, James R. Martin

Agriculture and Natural Resources Publications

The use of herbicides suggested in this publication is based on research at the Kentucky Agricultural Experiment Station and elsewhere. We have given what we believe to be the most effective herbicides, with the most suitable rates and times of application. Use of trade or brand names in this publication does not imply approval of the product to the exclusion of others which may be of similar or suitable composition.

Herbicide registrations and labels are constantly being revised and changed; therefore, herbicides recommended in this publication were registered for the prescribed uses when the publication was printed. If the registration …

Kentucky Forage Spokesperson Contest, Kentucky Forage And Grassland Council

Kentucky Grazing Conference

No abstract provided.

Can We Graze 300+ Days?, Glen Aiken

Kentucky Grazing Conference

Dependence on stored feeds during the winter months has been necessary in order to maintain body condition and meet nutrient requirements of cattle herds; unfortunately, cost of stored feeds typically are a major part of the farm budget. We know, all too well, that hay shortages and unstable feed ingredient markets have reduced profit potential in cattle production. This has further placed higher demands on supplies of co-product feeds to cause prices of these alternative feeds to rise and make them less cost effective. There will likely be less reliance on concentrate and co-product feeds as the forage-based livestock industry …

Pastures For Horses, Robert Coleman

Kentucky Grazing Conference

The horse evolved as a grazing animal. In order to consume enough forage to meet the horses’ nutritional needs a significant amount of time would be spent each day grazing. The pattern of selecting forage-moving to the next area starting to graze again can easily translate into 14 to 16 hours of grazing activity each day. The level of grazing activity will also be affected by the available forage and the daily access to pasture.

Pastures For Goats And Sheep, Greg Brann

Kentucky Grazing Conference

Pasture for sheep is not that different than that for cattle but pasture for goats is very different. Sheep are grazers like cattle whereas goats are browsers like deer. Even though grass and clover are not a goats preference if all of the forage present is grass and clover goats will eat it. Due to goats and sheep being more prey animals than cattle they don’t like to wade off into tall vegetation, also it takes more energy for them to move through tall growth. Many plants that we traditionally consider weeds become desirable forbs when goats or sheep are …

The Role Of Weed Control In Profitable Pastures, Scott Flynn, Pat Burch

Kentucky Grazing Conference

Pasture weeds compete for resources such as space, water, and nutrients. This competition reduces forage yield which in turn reduces the carrying capacity of a pasture. Although herbicide applications are needed to gain a quick upper hand on weed control most producers are deterred due to cost, the potential loss of pasture legumes, labor, or the belief that herbicide applications are required frequently to keep weed population under control. However, herbicide use in pastures should not be looked at in this manner but instead as an investment that can pay for itself very quickly and easily, and be long-term especially …

Role Of Legumes In Pastures, Garry D. Lacefield

Kentucky Grazing Conference

Successful livestock production is dependent on forage programs which supply large quantities of adequate quality, homegrown feed. A major percentage of the feed units for beef (83%) and dairy (61%) cattle come from forages. In addition, forages supply an estimated 91%, 72%, 15% and 99% of the nutrients consumed by sheep and goats, horses, swine and ruminant wildlife, respectively.

(How I Think About) Kentucky's Pastures: One Of Kentucky's Untapped Resources, Jimmy C. Henning

Kentucky Grazing Conference

One of the privileges of old(er) age is the prerogative to take liberties with assigned tasks. At the risk of confusing producers and offending more scientifically-current forage scientists, the topic of pasture as an untapped resource presented an opportunity to address task from an unexpected angle. Certainly, Kentucky’s pastures are a resource with untapped potential. But the idea that their value as a resource depends on how we think about them is one worth pursuing.

Foreword And Kfgc Award Winners [2013], Garry D. Lacefield, Christi L. Forsythe

Kentucky Grazing Conference

No abstract provided.

Geogram 2013, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Nitrogen And Potassium Dynamics Of Selected Indiana Soils, Chun Zhao

Open Access Dissertations

Nitrogen (N) is the most limiting essential nutrient for crop growth. Numerous studies have been performed to improve N fertilizer recommendations. Accurate prediction of soil N supply has been found to be one of the most important factors that determine optimum fertilizer N rates. Seven soils collected from various locations across Indiana at four different depths were tested for N mineralization potential. Results showed that laboratory mineralizable N in the top layer (0-15 cm) of the seven soils ranged from 50 to 68 mg N kg-1 soil. In addition, more than 50% of the total mineralizable N was contributed from …

Hydrogeologic Variations Across A Barrier Island That Influence Inter-Dune Wetlands False Cape State Park, Virginia, Matthew Collier Richardson

OES Theses and Dissertations

False Cape State Park in southeastern Virginia Beach, Virginia contains a transgressive barrier island complex. Inter-dune swales located on the eastern coast of the barrier island contain soils that experience hydric conditions. However, these swales lack the prolonged presence of hydric soil indicators that are necessary for a site to be officially recognized as a jurisdictional wetland. The appearance and subsequent disappearance of redoximorphic wetland soil features in the young, sandy soils of the inter-dune swales here may stem from changes in the patterns of groundwater recharge and discharge across the island. These soils are being monitored by the Mid …

Report Card On Sustainable Natural Resource Use In Agriculture, Robert Summers, David Weaver

All other publications

Condition and trend Nutrients, such as phosphorus (P), are essential for profitable agriculture in the south-west of WA; however, excess P – more than is required for optimal production – is stored in many agricultural soils. On average, pasture soils and arable soils contain 1.3 times and 1.6 times respectively, as much P as is required for optimal production. Production in P-enriched soils is more likely to be constrained by soil acidity (50–60% of pasture and arable soils), potassium (K) (50% of pasture soils and less than 10% of arable soils), and sulphur (S) (30% of pasture soils). Management implications …

Report Card On Sustainable Natural Resource Use In Agriculture : Status And Trend In The Agricultural Areas Of The South-West Of Western Australia, Department Of Agriculture And Food, Western Australia

Books & book chapters

This report card summarises our current knowledge of the status and trend in the natural resource base in the agricultural areas of the south-west of Western Australia (WA) and provides a discussion of the implications for agricultural industries.

The condition of our natural resources is a complex interaction of numerous processes. In simple terms however, the performance of the land is driven by three primary factors: climate, land characteristics and land management. The first two factors are largely out of the control of land managers, and in a drying and variable climate, land management practices need to be able to …

The Influence Of Soil Organic Matter Stabilization Mechanisms On Carbon Mean Residence Time Within Various Ecosystems In The United States, Vicky Lynn Giese, Kate Heckman Phd

STAR Program Research Presentations

Some terrestrial ecosystems and soils serve as carbon sinks, partially offsetting rising atmospheric CO₂ levels. Physiochemical mechanisms of soil organic matter (SOM) stabilization affect how carbon stocks respond to global warming. In order to clarify the variance in SOM stabilization mechanisms across different soil types, SOM abundance, distribution and mean residence time (MRT) were compared for thirty-two soil samples from six ecosystems across the United States. Soils were previously described, collected and archived by the United States Geological Survey. Samples were processed by LLNL at the Center for Accelerator Mass Spectrometry (CAMS) using density fractionation to separate particulate organics …