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Mechanisms Of Nutrient Limitation And Nutrient Acquisition In Managed And Unmanaged Forest Ecosystems, Matthew A. Vadeboncoeur May 2013

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 …


Analysis Of The Blancan Procyonids Of Florida, Laura S. Gilmore May 2013

Analysis Of The Blancan Procyonids Of Florida, Laura S. Gilmore

Electronic Theses and Dissertations

Procyonids are well known biologically but knowledge of their fossil record is comparatively sparse. This study seeks to describe a sample of late Blancan procyonid fossils composed mostly of postcranial and dental material. Fossils are analyzed using linear and 2D geometric morphometrics and compared with a large sample of modern specimens from a wide geographic area to understand the range of intraspecific variation. The large Procyon species is described as a new taxon based on morphology of the postcrania and lower dentition, while another Procyon species is also described as new due to an apomorphy in the upper dentition. A …


Groundcover Management System And Nutrient Source Impact Physical Soil Quality Indicators In An Organically Managed Apple Orchard, Neal Mays May 2013

Groundcover Management System And Nutrient Source Impact Physical Soil Quality Indicators In An Organically Managed Apple Orchard, Neal Mays

Graduate Theses and Dissertations

In March 2006, four groundcover management systems (GMS) and two nutrient sources (NS) were implemented for their ability to alter the soil physical condition of a newly established, organically managed apple (Malus x domestica Borkh.) orchard. Annual applications of municipal green compost (GC), shredded office paper (SP), wood chips (WC), and mow-blow (MB) grass mulch were utilized as GMS, and NS supplied to trees were from composted poultry litter (PL), a commercial organic fertilizer (CF), or an untreated control (NF) in a 4x3 factorial study. An established, conventionally-managed orchard was located adjacent to the organic research orchard on the same …


A Latest Carboniferous Warming Spike Recorded By A Fusulinid-Rich Bioherm In Timor Leste: Implications For East Gondwana Deglaciation, Vladimir I. Davydov, David W. Haig, Eujay Mccartain Apr 2013

A Latest Carboniferous Warming Spike Recorded By A Fusulinid-Rich Bioherm In Timor Leste: Implications For East Gondwana Deglaciation, Vladimir I. Davydov, David W. Haig, Eujay Mccartain

Geosciences Faculty Publications and Presentations

During the late Paleozoic and early Mesozoic Timor lay in the northern part of the north–south East Gondwana rift system along which the western margin of Australia later developed. Discovery of a latest Gzhelian bioherm in the central highlands of Timor Leste has implications for latest Carboniferous–earliest Permian climate history and deglaciation in basins further south in the rift system.

Limestone outcrop of the Maubisse Formation near the village of Kulau is recognized as a bioherm with a massive lower unit, including reef framework at the base, and a bedded grainstone upper unit. The bioherm developed on a basalt substrate …


Cave Taphonomy, Amberly Rounds Apr 2013

Cave Taphonomy, Amberly Rounds

The Review: A Journal of Undergraduate Student Research

In lieu of an abstract, below is the first paragraph of the paper.

Savrda and Lewis Gastaldo define taphonomy as the paleontological subdiscipline which is concerned with the process responsible for any organism becoming part of the fossil record, and how these processes influence information in the fossil record (Gastaldo 1996, 1). Lee Lyman goes on to state that even more so it is the science dealing with the laws of burial or embedding (Lyman l). In this paper taphonomy will be discussed along with its use in cave settings mainly during the Pleistocene era. Mary C. Steiner makes it …


Fertilizer: How Much Is In Each Bale?, Dennis Hancock Feb 2013

Fertilizer: How Much Is In Each Bale?, Dennis Hancock

Kentucky Alfalfa and Stored Forage Conference

What do you see when you look at a bale? Certainly, many would say it is a source of feed for our livestock. Others see a commodity that is sold to their customers. These are the most important aspects of any forage. But, there is one other intrinsic value worth noting… its nutrient content. In a sense, it is a bale of fertilizer.


Tackling Change: Future-Proofing Water, Agriculture, And Food Security In An Era Of Climate Uncertainty, Peter G. Mccornick, Vladimir Smakhtin, Luna Bharati, Robyn Johnston, Matthew Mccartney, Fraser Sugden, Floriane Clement, Beverly Mcintyre Jan 2013

Tackling Change: Future-Proofing Water, Agriculture, And Food Security In An Era Of Climate Uncertainty, Peter G. Mccornick, Vladimir Smakhtin, Luna Bharati, Robyn Johnston, Matthew Mccartney, Fraser Sugden, Floriane Clement, Beverly Mcintyre

Daugherty Water for Food Global Institute: Faculty Publications

In 1950 the global population was just over 2.5 billion. Now, in 2013, it is around 7 billion. Although population growth is slowing, the world is projected to have around 9.6 billion inhabitants by 2050. Most of the population increase will be in developing countries where food is often scarce, and land and water are under pressure. To feed the global population in 2050 the world will have to produce more food without significantly expanding the area of cultivated land and, because of competition between a greater number of water users, with less freshwater. On top of land and water …


Ua12/13 Big Red, Small Planet, Christian Ryan-Downing , Editor, Leslie North , Editor Jan 2013

Ua12/13 Big Red, Small Planet, Christian Ryan-Downing , Editor, Leslie North , Editor

Sustainability Publications and Resources

At WKU, “The Spirit Makes the Master”. Our commitment to continuous improvement is clearly reflected in our sustainability efforts. WKU’s commitment to sustainability, whether demonstrated in campus operations or in educational programs, helps to ensure that our graduates are prepared to address the complicated environmental, social and economic issues we face today. They will be able to think critically, solve problems creatively and be engaged citizens. If that’s all we accomplish then we will have achieved great success. But our sustainability commitment pays dividends, as it also leads us to reduce our environmental footprint, practice social responsibility, and conserve natural …


Influence Of Organic Groundcovers On Mycorrhizal Colonization And Symbiosis Of Organically Managed Fruit Crops, Raven Anai Bough, Curt R. Rom Jan 2013

Influence Of Organic Groundcovers On Mycorrhizal Colonization And Symbiosis Of Organically Managed Fruit Crops, Raven Anai Bough, Curt R. Rom

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Ground covers have the potential to impact the crop rhizosphere biology, which includes organisms such as arbuscular mycorrhizal fungi (AMF), which in turn affect the crop host plant through symbiosis. There has been evidence that a ground cover that provides a suitable environment for colonization of AMF and subsequent symbiosis could be a tool in organic fruit production. The objective of this research was to compare colonization of AMF in strawberry plant (Frageria x ananassa cv. Radiance) and apple rootstocks (Malus x domestica, cv. M. 26) grown in a greenhouse affected by various ground cover treatments. Inoculation was achieved by …


The Influence Of Poultry Litter Biochar On Early Season Cotton Growth, Taylor D. Coomer, David E. Longer, Derrick M. Oosterhuis, Dimitra A. Loka Jan 2013

The Influence Of Poultry Litter Biochar On Early Season Cotton Growth, Taylor D. Coomer, David E. Longer, Derrick M. Oosterhuis, Dimitra A. Loka

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Cotton is known for being sensitive to cool, wet soils, especially in the early stages of growth. Amendments to soil can aid cotton seedlings in development and nutrient uptake. However, soil amendments can be costly and detrimental to the environment, and alternatives such as the addition of biochar have been considered. Biochar is produced from biomass that has gone through pyrolysis and has been shown to improve plant yield, microbial response, soil structure, soil cation–exchange capacity, and water use efficiency. This study was conducted to evaluate the effect of biochar on early season cotton growth. The aim of this study …


Phosphorus Cycling In The Sargasso Sea: Investigation Using The Oxygen Isotopic Composition Of Phosphate, Enzyme-Labeled Fluorescence, And Turnover Times, Karen Mclaughlin, Jill A. Sohm, Gregory A. Cutter, Michael W. Lomas, Adina Paytan Jan 2013

Phosphorus Cycling In The Sargasso Sea: Investigation Using The Oxygen Isotopic Composition Of Phosphate, Enzyme-Labeled Fluorescence, And Turnover Times, Karen Mclaughlin, Jill A. Sohm, Gregory A. Cutter, Michael W. Lomas, Adina Paytan

OES Faculty Publications

Dissolved inorganic phosphorus (DIP) concentrations in surface water of vast areas of the ocean are extremely low (<10 nM) and phosphorus (P) availability could limit primary productivity in these regions. We explore the use of oxygen isotopic signature of dissolved phosphate (δ18OPO4) to investigate biogeochemical cycling of P in the Sargasso Sea, Atlantic Ocean. Additional techniques for studying P dynamics including 33P-based DIP turnover time estimates and percent of cells expressing alkaline phosphatase (AP) activity as measured by enzyme-labeling fluorescence are also used. In surface waters, δ18OPO4 values were lower than equilibrium by 3–6%, indicative of dissolved organic phosphorous (DOP) remineralization by extracellular enzymes. An isotope mass balance model using a variety of possible combinations of …


Distribution And Impacts Of Petroleum Hydrocarbons In Louisiana Tidal Marsh Sediments Following The Deepwater Horizon Oil Spill, Rachel S. Hatch Jan 2013

Distribution And Impacts Of Petroleum Hydrocarbons In Louisiana Tidal Marsh Sediments Following The Deepwater Horizon Oil Spill, Rachel S. Hatch

Theses and Dissertations--Earth and Environmental Sciences

Following the 2010 Deepwater Horizon (DWH) spill, sediment cores were analyzed from marshes at various levels of oiling to determine how deeply oil penetrated sediment in these marsh environments, and if at these sites it had quantifiably affected benthic ecosystems. Minimum mixing depths were determined from penetration of the lithogenic radionuclide 234Th, which ranged from 0.25 to 4.5 cm. Sediment accumulation rates were determined using 210Pb, with verification from 137Cs in selected cores. Lead-210 profiles revealed long-term (decadal) mixing. Bay Jimmy, Louisiana was significantly affected by the DWH oil spill, as indicated by total polycyclic aromatic hydrocarbon …


Stress Features In Terra Rossa Soil Under Traditional Olive Cultivation: A Micromorphological And Mineralogical Characterization, Salvatore Madrau, Claudio Zucca, İhsan Akşi̇t, Valeria Fiori Jan 2013

Stress Features In Terra Rossa Soil Under Traditional Olive Cultivation: A Micromorphological And Mineralogical Characterization, Salvatore Madrau, Claudio Zucca, İhsan Akşi̇t, Valeria Fiori

Turkish Journal of Earth Sciences

This study analyzes the micromorphological and mineralogical properties of a Terra Rossa soil under a traditional Mediterranean olive grove. It highlights the microscopic and sub-microscopic features generated by the permanent crop cover. The study area, where the land use has remained unchanged for the last 150 years, is near Sassari (Sardinia, Italy) and is characterized by dominant Terra Rossa developed on Miocene marine limestone. Two soil profiles were opened and described in July 2009, 1 under the canopy of an olive tree and 1 between the trees. Chemical and physical analyses were carried out. Undisturbed aggregates were collected from all …


Impact Of Pb-Zn Mining Activity On Surficial Sediments Of Lake Kalimanci(Fyr Macedonia), Petra Vrhovnik, Nastja Rogan Smuc, Tadej Dolenec, Todor Serafimovski, Matej Dolenec Jan 2013

Impact Of Pb-Zn Mining Activity On Surficial Sediments Of Lake Kalimanci(Fyr Macedonia), Petra Vrhovnik, Nastja Rogan Smuc, Tadej Dolenec, Todor Serafimovski, Matej Dolenec

Turkish Journal of Earth Sciences

The activities of the Sasa mine have led to industrial discharge being released into Lake Kalimanci since the beginning of mining activity in 1954. For this reason, an ecological risk assessment is urgently required. In the present study, surficial lake sediments were analyzed using inductively coupled plasma mass spectrometry (ICP-MS), with all geochemistry data processed using Statistica 8. In order to assess the environmental pollution status, 2 environmental factors were established, while for the determination of chemical fractionation of toxic metals a sequential extraction procedure was carried out. Concentrations of As, Mo, Zn, Ni, Co, Pb, Cd, and Cu in …


Carbon Farming In Wa, Department Of Agriculture And Food, Western Australia, Department Of Regional Development And Lands, Western Australia Jan 2013

Carbon Farming In Wa, Department Of Agriculture And Food, Western Australia, Department Of Regional Development And Lands, Western Australia

Natural resources published reports

Fact sheets:

1. Applying biochar to improve soil quality and crop productivity

2. Reducing methane emissions from cattle using feed additives

3. Cattle breeding for lower greenhouse gas emissions

4. Managing genetic codes to reduce methane emissions from cattle

5. Managing pastures and stocking rate to reduce methane emissions from cattle

6. Claying as a method of increasing soil carbon content

7. Green and brown manuring as part of carbon farming

8. Permanent environmental plantings to earn carbon credits

9. Nitrous oxide emissions from agricultural soils

10. Sheep genetics in methane reduction

11. Managing sheep pastures to reduce methane production …


Palaeoecological Analysis Of The Decline In Stromatolite Abundance During The Ordovician Period, Noran Mhm El-Sherif Jan 2013

Palaeoecological Analysis Of The Decline In Stromatolite Abundance During The Ordovician Period, Noran Mhm El-Sherif

Browse all Theses and Dissertations

A stromatolite is a laminated benthic microbial deposit. Its uniqueness arises from being present since the Precambrian to the present. Stromatolites recorded a peak time during the Mesoproterozoic, subsequently they witnessed abrupt rises and falls in abundance with the steepest decline in the Ordovician period, from which it never recovered from. There is no consensus yet regarding the reasons behind the decline of stromatolites. Thus the decline of these microbial deposits remains an enigma. Additionally, a literature gap exists regarding the reasons that specifically led to the Ordovician decline. Accordingly, the focus of this literature-based MSc. thesis is to find …


Putting Local Knowledge And Context To Work For Gunnison Sage-Grouse Conservation, Corrine Noel Knapp, James Cochran, F. Stuart Chapin Iii, Gary Kofinas, Nathan Sayre Jan 2013

Putting Local Knowledge And Context To Work For Gunnison Sage-Grouse Conservation, Corrine Noel Knapp, James Cochran, F. Stuart Chapin Iii, Gary Kofinas, Nathan Sayre

Human–Wildlife Interactions

Successful conservation requires adequate understanding of focal species and ecology, practices that may assist species survival, and a community of people willing and able to conserve the species. For many species at risk, we operate with imperfect knowledge in complex conservation contexts. In this case study involving the Gunnison sage-grouse (Centrocercus minimus), we interviewed 26 community-defined local experts, including both those with and without related academic degrees, to assess the utility of local knowledge for understanding and informing conservation opportunities.This project suggests several benefits of integrating local knowledge that apply specifically to rare and endemic populations, including the …


Response Of A Small Population Of Greater Sage-Grouse To Tree Removal: Implications Of Limiting Factors, S. Nicole Frey, Rachel Curtis, Kevin Heaton Jan 2013

Response Of A Small Population Of Greater Sage-Grouse To Tree Removal: Implications Of Limiting Factors, S. Nicole Frey, Rachel Curtis, Kevin Heaton

Human–Wildlife Interactions

In Utah, greater sage-grouse (Centrocercus urophasianus; hereafter, sage-grouse) range has been reduced to 50% of what is considered historical availability due to habitat degradation and loss. In an effort to improve sage-grouse habitat in southern Utah, the U.S. Bureau of Land Management (BLM) conducted a tree-removal treatment in 2005. We conducted a study to determine if (a) the tree-removal treatment was effective at creating new sage-grouse habitat, and (b) if characteristics of used habitat were similar to those reported in previous literature. The treatment resulted in increased abundance of grasses and forbs. Additionally, shrub percentage cover and height …


Factors Influencing Survival And Productivity Of Pronghorn In A Semiarid Grass-Woodland In East-Central New Mexico, Louis C. Bender, Jon C. Boren, Heather Halbritter, Shad Cox Jan 2013

Factors Influencing Survival And Productivity Of Pronghorn In A Semiarid Grass-Woodland In East-Central New Mexico, Louis C. Bender, Jon C. Boren, Heather Halbritter, Shad Cox

Human–Wildlife Interactions

Pronghorns (Antilocapra americana) are an important source of revenue and recreation for property managers throughout New Mexico, but have been declining in number. We documented body condition, survival, production of fawns, and trends in population size of pronghorns on the Corona Range and Livestock Research Center (CRLRC), a working research ranch and wildlife enterprise located in east-central New Mexico, from 2006 through 2011. Accrual of all indices of condition and size of both adult female and adult male pronghorns was positively associated with precipitation during June to July, August to September, and annually. Annual survival rates of females …


Computational Prediction Of The Sporulation Network In Clostridium Thermocellum, Changyi Jiang Jan 2013

Computational Prediction Of The Sporulation Network In Clostridium Thermocellum, Changyi Jiang

Dissertations, Master's Theses and Master's Reports - Open

Sporulation is a process in which some bacteria divide asymmetrically to form tough protective endospores, which help them to survive in a hazardous environment for a quite long time. The factors which can trigger this process are diverse. Heat, radiation, chemicals and lacking of nutrition can all lead to the formation of endospores. This phenomenon will lead to low productivity during industrial production. However, the sporulation mechanism in a spore-forming bacterium, Clostridium theromcellum, is still unclear. Therefore, if a regulation network of sporulation can be built, we may figure out ways to inhibit this process. In this study, a …


Seasonal Dimorphism In The Horny Bills Of Sparrows, Russell Greenberg, Matthew Etterson, Raymond M. Danner Dec 2012

Seasonal Dimorphism In The Horny Bills Of Sparrows, Russell Greenberg, Matthew Etterson, Raymond M. Danner

United States Environmental Protection Agency: Publications

Bill size is often viewed as a species-specific adaptation for feeding, but it sometimes varies between sexes, suggesting that sexual selection or intersexual competition may also be important. Hypotheses to explain sexual dimorphism in avian bill size include divergence in feeding niche or thermoregulatory demands, intrasexual selection based on increased competition among males, or female preference. Birds also show seasonal changes in bill size due to shifts in the balance between growth rate and wear, which may be due to diet or endogenous rhythms in growth. Insight into the function of dimorphism can be gained using the novel approach of …


Interactions Of Zoo Plankton And Phytoplankton With Cyanobacteria, Rebecca J. Alexander Dec 2012

Interactions Of Zoo Plankton And Phytoplankton With Cyanobacteria, Rebecca J. Alexander

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

Cyanobacteria are a major concern in Nebraska reservoirs and are capable of producing toxins that can cause skin irritations and gastrointestinal problems, as well as affect the nervous system. It is important to determine the mechanisms that can cause cyanobacteria blooms due to the effect they can have on human health. The interaction of zooplankton and other phytoplankton groups with cyanobacteria is important because there is a biological component in surface waters that should be taken into consideration along with the physical and chemical parameters that have been noted to promote cyanobacteria. For example, zooplankton have the ability to alter …


Interactions Of Zooplankton And Phytoplankton With Cyanobacteria, Rebecca Alexander Dec 2012

Interactions Of Zooplankton And Phytoplankton With Cyanobacteria, Rebecca Alexander

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

Cyanobacteria are a major concern in Nebraska reservoirs and are capable of producing toxins that can cause skin irritations and gastrointestinal problems, as well as affect the nervous system. It is important to determine the mechanisms that can cause cyanobacteria blooms due to the effect they can have on human health. The interaction of zooplankton and other phytoplankton groups with cyanobacteria is important because there is a biological component in surface waters that should be taken into consideration along with the physical and chemical parameters that have been noted to promote cyanobacteria. For example, zooplankton have the ability to alter …


The Impact Of Creosote Bush (Larrea Tridentata) And Biological Soil Crust On Ca Distribution In Arid Soils Of The Mojave Desert, Brittany Myers Dec 2012

The Impact Of Creosote Bush (Larrea Tridentata) And Biological Soil Crust On Ca Distribution In Arid Soils Of The Mojave Desert, Brittany Myers

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ca is an important nutrient that plays a role in membrane stability and cell repair in plant life. This study examines the impact of creosote bush (Larrea tridentata) and biological soil crust on calcium cycling and distribution in desert soils in order to explore the use of Ca as a biosignature. Samples of creosote bush, biological soil crust and eolian dust were taken at two field sites in the Mojave Desert. The first site is located in Eldorado Valley, NV, a soil formed on a young (800-1200 years) alluvial fan deposit; the second site is located on a late Holocene-aged …


Examining The Impact Of Pau Jacaré (Piptadenia Gonoacantha) Growth On Soil Fertility In The Brazilian Atlantic Rainforest, Aleksandra Ponomareva Oct 2012

Examining The Impact Of Pau Jacaré (Piptadenia Gonoacantha) Growth On Soil Fertility In The Brazilian Atlantic Rainforest, Aleksandra Ponomareva

Environmental Analysis Program Mellon Student Summer Research Reports

The Atlantic Rainforest of Brazil is an area of astounding diversity in both flora and fauna, taking its place among the top five “biodiversity hotspots” in the world. However, in the past 40 or 50 years the area has been increasingly threatened by the presence of humans – approximately 93% of the Rainforest has disappeared as a result of exploitation (Turner 2004). Unsustainable farming practices, as well as logging, cattle ranching and mining activities have caused soil infertility, water depletion, erosion and destruction of ecosystems. This project examines the effects of the Pau Jacaré, Piptadenia gonoacantha, tree on soil health …


Trace Element Soil Contamination At Urban Community Gardens In Washington, Dc, Adam J. Long Aug 2012

Trace Element Soil Contamination At Urban Community Gardens In Washington, Dc, Adam J. Long

Environmental Analysis Program Mellon Student Summer Research Reports

In recent years, urban gardening has become a popular form of environmental, food, and social justice. Urban community gardens such as those in Washington, DC can reduce the environmental footprint of food production, provide access to healthy produce in “food deserts,” and provide other social, educational, and even financial benefits. However, the rising popularity of urban gardening has put many people in close contact with urban soils, which are likely to contain various contaminants due to concentrated human activity over extended periods of time. This study investigates heavy metal soil contaminants found in community gardens located in Washington, DC. 45 …


Pastoral Lease Assessment Using Geospatial Analysis, T P. Robinson, P E. Novelly, R Corner, Philip Thomas, A Russell-Browm Aug 2012

Pastoral Lease Assessment Using Geospatial Analysis, T P. Robinson, P E. Novelly, R Corner, Philip Thomas, A Russell-Browm

Resource management technical reports

Seven remote sensing based Vegetation Indices (NDSVI, STVI-3, NDVI, Green + Red, Red, Land Monitor and STVI-1) were tested for their potential to discriminate between “poor” and “good” range condition assessments in Western Australia’s pastoral rangelands. Indices were computed using the Australian Greenhouse Office National Carbon Accounting System (AGO NCAS) repository of calibrated Landsat TM/ETM+ mosaics. Discrimination potential was assessed at two levels of stratification – station level (identical to the stratification used to collect the traverse data), and functional group level (an aggregation of similar land systems);


Selenium Removal In Nutrient-Amended Pilot-Scale Constructed Wetland Treatment Systems, Peter Van Heest Aug 2012

Selenium Removal In Nutrient-Amended Pilot-Scale Constructed Wetland Treatment Systems, Peter Van Heest

All Theses

ABSTRACT
In a year-long study, pilot-scale constructed wetland treatment systems (CWTSs) targeted removal of selenium (Se) from a simulated impaired water through dissimilatory Se reduction. Effects of temperature and precipitation on the treatment of Se in the CWTSs were investigated. The experimental design consisted of CWTSs amended with a fermented yeast product (AquaSmartTM, Diamond V¨, Cedar Rapids, IA), which served as a nutrient source for Se-reducing bacteria, at mass loadings of 1.75, 3.5, 5.25, 7, and 8.75 mg/min. The 5 µg/L treatment goal for CWTS outflow concentration was measured in 69 of 378 samples taken from all CWTSs. Of the …


Soil Biochemical Changes Induced By Poultry Litter Application And Conservation Tillage Under Cotton Production Systems, Regine Mankolo, Chandra Reddy, Zachary Senwo, Ermson Nyakatawa, Seshadri Sajjala Jul 2012

Soil Biochemical Changes Induced By Poultry Litter Application And Conservation Tillage Under Cotton Production Systems, Regine Mankolo, Chandra Reddy, Zachary Senwo, Ermson Nyakatawa, Seshadri Sajjala

Agricultural and Environmental Sciences Faculty Research

Problems arising from conventional tillage (CT) systems (such as soil erosion, decrease of organic matter, environmental damage etc.) have led many farmers to the adoption of no-till (NT) systems that are more effective in improving soil physical, chemical and microbial properties. Results from this study clearly indicated that NT, mulch tillage (MT), and winter rye cover cropping systems increased the activity of phosphatase, β-glucosidase and arylsulfatase at a 0–10 cm soil depth but decreased the activity of these enzymes at 10–20 cm. The increase in enzyme activity was a good indicator of intensive soil microbial activity in different soil management …


The Spatial Distribution Of K-Factor Values Across A Toposequence And A Soil Survey Map Unit, Jacqueline Elizabeth Tilligkeit Jul 2012

The Spatial Distribution Of K-Factor Values Across A Toposequence And A Soil Survey Map Unit, Jacqueline Elizabeth Tilligkeit

Master's Theses

Rivers and streams are adversely affected by an increase in sedimentation in their waters from eroding land. High sediment loads in streams can bury fish eggs and prevent hatching, increasing nutrients in the water causing algae blooms, or even contaminating the water with heavy metals carried in or on the aggregates. The erodibility of soil is valuable knowledge to all land users so that we may predict soil loss and its potential to pollute streams. This is done by using the Revised Universal Soil Loss Equation (RUSLE). By predicting soil loss from a given landscape, land managers can take mitigation …