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Benefits And Costs Of Saltland Pastures On Moderately Salt-Affected Land, Justin Hardy, Arjen Ryder

Resource management technical reports

Summary The analyses in this report show that there could be significant economic benefits to the state, regions and affected farm businesses from establishing improved saltland pasture systems on moderately salt-affected land. The report clearly describes the methods of analysis and the assumptions about prices, productivity and adoption levels. The price of grain has been used as the key factor controlling the economic value of the saltland grazing because grain is the alternative supplementary feed for sheep over the summer and autumn period. Therefore, where yield is below break-even on moderately salt-affected land, it has a higher economic value and …

Distribution Of Soil Density At A Bottomland Hardwood Forest Wetland Restoration, Chicot County, Arkansas, B. E. Sleeper, Robert L. Ficklin

Journal of the Arkansas Academy of Science

Bottomland hardwood forest (BLHF) soils provide a myriad of ecosystem services, yet much information is lacking with respect to how soil physical properties influence biogeochemical cycling along topographic gradients. Current patterns of vegetation at a 149ha wetland restoration site in Chicot County, Arkansas, suggest the presence of ecologically significant variation in soil properties within the Perry Clay soil series. A study was initiated in the Lower Mississippi Alluvial Valley (LMAV) to map soil bulk density and texture as well as to identify the interrelationships between soil physical properties, soil organic carbon, and total nitrogen. A random grid was used to …

Slurry Seeding Cover Crops, Edwin Alexander Suarez

Open Access Theses

Cover crops improve soil quality through increased organic matter, biological activity, aggregate stability, water infiltration, and nutrient cycling. Slurry seeding, the co-application of cover crop seed and swine (Sus domesticus) manure, is a new practice that saves fuel, time and labor. High salinity and/or ammonia, among other components in swine manure, may reduce cover crop seed germination and limit the use of slurry seeding. Ten cover crop species were evaluated to compare the effects of swine manure components on cover crop seed germination. Seed germination percentages and rates were affected by swine manure but not by equivalent salinity levels established …

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 …

Evaluation Of Cover Crops In High Tunnel Vegetable Rotation, Tyler A. Patrick, Neal Mays, Jason Mcafee, Curt R. Rom

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

Organic vegetable production within high tunnels allows for an extended growing season, crop protection, and environmental control. The USDA National Organic Program (NOP) standards mandate evidence that the soil has been maintained and improved over the course of production. Previous studies have indicated the potential of cover crops for reducing competitive vegetation, and improving soil quality, thus resulting in greater plant growth, nutrient uptake, and yield. However, there has been limited work in the confines of high tunnels as part of a tunnel-system rotation. Ten nitrogen-fixing and ten non-legume cover crops were established under a high tunnel and evaluated for …

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 …

Managing Soil Microbial Communities With Organic Amendments To Promote Soil Aggregate Formation And Plant Health, Shawn T. Lucas

Theses and Dissertations--Plant and Soil Sciences

The effects of managing soil with organic amendments were examined with respect to soil microbial community dynamics, macroaggregate formation, and plant physio-genetic responses. The objective was to examine the possibility of managing soil microbial communities via soil management, such that the microbial community would provide agronomic benefits. In part one of this research, effects of three amendments (hairy vetch residue, manure, compost) on soil chemical and microbial properties were examined relative to formation of large macroaggregates in three different soils. Vetch and manure promoted fungal proliferation (measured via two biomarkers: fatty acid methyl ester 18:2ω6c and ergosterol) and also stimulated …

Transformations, Bioavailability And Toxicity Of Manufactured Zno Nanomaterials In Wastewter, Sewwandi Rathnayake

Theses and Dissertations--Plant and Soil Sciences

In order to properly evaluate the ecological and human health risks of ZnO Manufactured nanomaterials (MNMs) released to the environment, it is critical to understand the likely transformation products in the wastewater treatment process and in soils receiving biosolids. To address this critical knowledge gap, we examined the transformation reactions of 30 nm ZnO MNMs in single component and multi-component systems, with phosphate and natural organic matter (NOM). We also assessed the influence of nano ZnO transformation on the bioavailability, and toxicity of ZnO transformation products to Triticum aestivum. The data revealed that ZnO MNMs react with phosphate at …

Factors Influencing The Establishment And Survival Of Native Hardwood Tree Seedlings Of The Kentucky Inner Bluegrass Blue Ash-Oak Savanna-Woodland, James D. Shaffer

Theses and Dissertations--Biology

Historically, the Kentucky Inner Bluegrass blue ash-oak savanna-woodland was the primary ecosystem of the Inner Bluegrass Region (IBR) of Kentucky. After European settlement, the majority (>99%) of Bluegrass savanna was converted to agricultural and urban land uses. Currently remnant savanna tree species are failing to recruit. Therefore, a long-term restoration ecology project researching competition and disturbance on seedling establishment, survival, and growth has been established at Griffith Woods (the largest remaining savanna in Kentucky) in Harrison Co., KY. Fourteen native hardwood tree species (a total of 6,168 seedlings) have been experimentally planted. Light, soil, surrounding vegetation, and herbivory, factors …

Abiotic Nitrate And Nitrite Reactivity With Iron Oxide Minerals, Prakash Dhakal

Theses and Dissertations--Plant and Soil Sciences

Under iron (Fe³⁺)-reducing conditions where aqueous Fe²⁺ and unreduced solid Fe³⁺-oxides commonly coexist, soil Fe²⁺ oxidation has been shown to be coupled with nitrate (NO₃^-) reduction. One possible secondary reaction is the involvement of NO₃^- and nitrite (NO₂^-) with Fe-oxide minerals found in many natural environments. Yet, spectroscopic measurements and kinetic data on reactivity of NO₃^- and NO₂^- with Fe-containing oxide minerals such as goethite (a-FeOOH), and magnetite (Fe₃O­₄) are not found in the literature. The reactivity of …

Cave Ventilation Is Influenced By Variations In The Co2-Dependent Virtual Temperature, Enrique P. Sánchez-Cañete, Penélope Serrano-Ortiz, Francisco Domingo, Andrew S. Kowalski

International Journal of Speleology

Dynamics and drivers of ventilation in caves are of growing interest for different fields of science. Accumulated CO₂ in caves can be exchanged with the atmosphere, modifying the internal CO₂ content, affecting stalagmite growth rates, deteriorating rupestrian paintings or creating new minerals. Current estimates of cave ventilation neglect the role of high CO₂ concentrations in determining air density – approximated via the virtual temperature (T_v) –, affecting buoyancy and therefore the release or storage of CO₂. Here we try to improve knowledge and understanding of cave ventilation through the use of T …

Phosphorus Transport And Distribution In Kentucky Soils Prepared Using Various Biochar Types, Anvesh Reddy

Masters Theses & Specialist Projects

Conserving the environment is an issue that is gaining popularity day by day. Phosphorus transfer from agricultural soils is an important environmental issue that is being closely observed as the transport of phosphorous to water bodies is adversely affecting water quality due to accelerated eutrophication. It is important to establish phosphorous models that accurately account for soil test phosphorous. Standard models like SWAT (Soil and Water Assessment Tool) and EPIC (Environmental Policy Integrated Climate) were designed for serving this purpose. They are now used as the basis for developing new models that can more accurately account for the phosphorus transport, …

Long-Term Effects Of Rice Rotation, Tillage, And Fertility On Near-Surface Soil Carbon And Nitrogen Cycling, Jill Marie Motschenbacher

Graduate Theses and Dissertations

Rice (Oryza sativa L.)-based cropping systems are different from other row crops due to the flood-irrigation scheme used from about one month after planting to a few weeks prior to harvest. The frequent cycling between anaerobic (i.e., flooding during the growing season) and aerobic (i.e., generally, the remainder of the year) conditions can influence the rate of soil organic matter (SOM) decomposition, which can greatly influence carbon (C) and nitrogen (N) storage and sequestration in the soil over time. Therefore, a study was conducted on a silt-loam soil (fine, smectitic, thermic, Typic Albaqualf) at the Rice Research and Extension Center …

Evaluation Of The Effects Of Absorption Field Product Architecture Type On Effluent Dispersal And Soil Chemical Properties In A Profile-Limited Soil, Nina J.M. Prater

Graduate Theses and Dissertations

On-site wastewater treatment systems (OWTSs) are commonly used by households in areas of low population density to treat household wastewater and recycle it back to the environment. The traditional absorption field product used in OWTSs is a pipe-and-gravel architecture type, which has been used for decades and is the basis for most design regulations. However, new products of differing architecture types including chambers, polystyrene-aggregate, pipe-and-tire-chip, and gravel-less-pipe systems have recently become available. A three-year field study was conducted in Bethel Heights, AR to assess the performance of several newer products and to compare different architecture types to the traditional pipe-and-gravel …

Restoration Of Biological Soil Crust On Disturbed Gypsiferous Soils In Lake Mead National Recreation Area, Eastern Mojave Desert, Lindsay P. Chiquoine

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biological soil crusts (BSCs) are sensitive to anthropogenic disturbances. Natural recovery takes many years. Active restoration decreases recovery time. Native BSC inocula, which included lichens and mosses, salvaged from gypsiferous soil habitats in Lake Mead National Recreation Area (LMNRA) in the eastern Mojave Desert were stored dry for two years and applied to disturbed soil after a road reconstruction in LMNRA and also used in laboratory experiments to test inoculation technique effectiveness. After 18 months, field results revealed positive relationships between inoculation and the presence of macroscopic BSC cover, cyanobacteria abundance, soil stability, and ammonium concentrations. Chlorophyll fluorescence monitoring of …

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

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 …

Geogram 2012, David J. Keeling, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Nebraska's Wetlands: Their Wildlife And Ecology, Paul A. Johnsgard

Conservation and Survey Division: Faculty and Staff Publications

1 An Overview of Nebraska's Wetlands

2 The Missouri Valley • Natural History Profiles of Some Missouri Valley Wetland Species • The Missouri Valley Wetlands

3 The Niobrara Valley Region • Natural History Profiles of Some Niobrara Valley Wetland Species • The Niobrara Valley Wetlands

4 The Platte Valley Region • Natural History Profiles of Some Platte Valley Wetland Species • The Central Platte Valley Wetlands • The North Platte Valley Wetlands

5 Other River Valley Wetlands • Natural History Profiles of Some Typical Riverine Species • The Elkhorn Valley Wetlands • The Loup Valley Wetlands • The Republican Valley …

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 …

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 …

Effects Of Precipitation Increase On Soil Respiration: A Three-Year Field Experiment In Subtropical Forests In China, Qi Deng, Dafeng Hui, Deqiang Zhang, Guoyi Zhou, Juxiu Liu, Shizhong Liu, Guowei Chu, Jiong Li

Biology Faculty Research

Background

The aim of this study was to determine response patterns and mechanisms of soil respiration to precipitation increases in subtropical regions.

Methodology/Principal Findings

Field plots in three typical forests [i.e. pine forest (PF), broadleaf forest (BF), and pine and broadleaf mixed forest (MF)] in subtropical China were exposed under either Double Precipitation (DP) treatment or Ambient Precipitation (AP). Soil respiration, soil temperature, soil moisture, soil microbial biomass and fine root biomass were measured over three years. We tested whether precipitation treatments influenced the relationship of soil respiration rate (R) with soil temperature (T) and soil …

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 …

The Effects Of Biochar Age And Concentration On Soil Retention Of Phosphorus And Infiltration Rate, Emilie Schneider

Natural Resources Management and Environmental Sciences

Changes in land use and land management practices are regarded as one of the main factors in altering the hydrogeological system, causing changes in runoff, surface supply yields, and the quality of receiving water (Tong and Chen, 2002). Phosphorus is a significant contributor to accelerated eutrophication of fresh water and is largely sourced from agricultural runoff (Sharpley et al., 1994). The dominant processes controlling solution composition in agricultural soils are primarily ‘chemical’ for P (i.e. adsorption/desorption and dissolution/precipitation) (Edwards and Withers, 1998). Biochar has chemical characteristics that have the potential to adsorb P or influence precipitation of P insoluble pools …

Using Environmental Variables And Soil Processes To Forecast Denitrification Potential And Nitrous Oxide Fluxes In Coastal Plain Wetlands Across Different Land Uses, Jennifer L. Morse, Marcelo Ardón, Emily S. Bernhardt

Environmental Science and Management Faculty Publications and Presentations

We examined relationships between denitrification (DNF) and nitrous oxide (N2O) fluxes and potentially important chemical and physical predictors to build a predictive understanding of gaseous N losses from coastal plain wetlands. We collected soil, gas, and pore water samples from 48 sampling locations across a large (440 ha) restored wetland, an adjacent drained agricultural field, and nearby forested wetlands every two months over two years. In summer and fall 2007, we measured soil DNF potential (21.6-3560 mg N m-3 d-1) and N2O efflux (-4.36-8.81 mg N m -2 d-1), along with 17 predictor variables. We developed statistical models for the …

North Central Region Soil Survey Conference Field Tour

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

A Chemical And Morphological Study Of Soils At The Cal Poly Vineyard, Glade A. Dlott

Natural Resources Management and Environmental Sciences

Despite cultivation for close to a decade, the soils at the Cal Poly vineyard have never been studied in detail. This study was designed to gain a better understanding of the soils for better management. Soil pits and auger holes were dug throughout the site to accurately classify soils. Soils were classified using USDA-NRCS Soil Taxonomy, and samples were taken from each horizon of each soil pit for chemical analysis. Four soil map units were delineated on the site. The pH, EC, total percent carbon and nitrogen, and plant available nitrate, sulfate, phosphate, base cations, and metal micronutrients of each …

Evaluation Of Hydraulic Conductivity Of Non Aqueous Phase Liquids In Partially Saturated Soils, Chijioke Ekeleme Akamiro

Civil & Environmental Engineering Theses & Dissertations

This study seeks to investigate a problem of predicting the hydraulic conductivity of NAPLs in partially saturated soils and to relate the hydraulic conductivity to basic soil parameters that are either easy to determine or are in wide use. To evaluate hydraulic conductivity in partially saturated soils, previous researchers have focused on flow geometry, soil and chemical properties, etc. used in CHEMFLO program by Nofziger et al., (1989) and saturation equations by such authors as Van Genutchen (1980) and Brooks and Corey (1964). Among those, the soil-water characteristic curve (SWCC) is the most widely used constitutive relations for unsaturated soils …

Implications For Old-Field Restoration: Diversity And Abundance Of Arbuscular Mycorrhizal Fungi In Soils Of Restored York Gum (Eucalyptus Loxophleba Subsp. Loxophleba) Sites Vs. Remnants., Jessica Wong

Independent Study Project (ISP) Collection

Arbuscular mycorrhizal fungi (AMF) may be critical to the restoration of ecosystem function in old-fields. Whether the diversity of the plant community is promoted by the AMF community or is the driving force of AMF diversity is unknown. We investigated two questions in the context of old-field restoration in southwestern Australia: 1) Does restoration of the plant community achieve the restoration of AMF and 2) Is AMF species diversity and abundance influenced by the plant species composition? Our study sites were located in the Ridgefield Experiment in the University of Western Australia’s “Future Farm”. Soil samples were collected from beneath …

Strawberry Growth, Yield, Fruit Nutrition, And Control Of Verticillium Wilt With Pre-Plant Soil Fumigants, Ozone, And Biological Control, Justin J. Scurich

Master's Theses

Verticillium wilt is a widespread soilborne disease of strawberry historically controlled by soil fumigation with methyl bromide (MB). MB was banned by the United Nations in 1995 and will be completely phased out by 2015. Research has concentrated on alternative methods of disease control without finding a single alternative able to replace MB in widespread disease control and yield increase. For the current study, strawberries were greenhouse grown in container pots filled with soil from both infested and non-infested areas of a commercial strawberry field in Watsonville, CA. Treatments included pre-plant soil fumigation with commercially available formulations of methyl bromide, …