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Articles 9721 - 9750 of 14281

Full-Text Articles in Soil Science

Trace Element Imbalance In Vegetation As A Threat To Free Ranging Cattle In The Gilgel Gibe Valley, Ethiopia, Thomas Van Hecke, Veronique Dermauw, Kechero Yisehak, Gijs Du Laing, Luc Duchateau, Geert P. J. Janssens Jan 2020

Trace Element Imbalance In Vegetation As A Threat To Free Ranging Cattle In The Gilgel Gibe Valley, Ethiopia, Thomas Van Hecke, Veronique Dermauw, Kechero Yisehak, Gijs Du Laing, Luc Duchateau, Geert P. J. Janssens

IGC Proceedings (1977-2023)

As in many tropical countries, natural pastures are the main source of nutrients for cattle in Ethiopia. However, there is limited information available with regard to trace element concentrations in Ethiopian forages. In this study, 58 plants were sampled in the Gilgel Gibe valley based on the observed ingestion by zebu cattle (Bos indicus) herds, grazing at different elevation and soil types, and analysed for copper (Cu), cobalt (Co), iron (Fe), molybdenum (Mo), manganese (Mn), sulfur (S), selenium (Se) and zinc (Zn). The effect of elevation, soil type and plant type on the above trace element concentrations was …


Variations An Α-Tocopherol And Β-Carotene Concentrations In Forage Legumes And Grasses Harvested At Different Sites And Maturity Stages, Elisabet Nadeau, Hanna Lindqvist, Søren Krogh Jensen, Nilla Nilsdotter-Linde, Anne-Maj Gustavsson Jan 2020

Variations An Α-Tocopherol And Β-Carotene Concentrations In Forage Legumes And Grasses Harvested At Different Sites And Maturity Stages, Elisabet Nadeau, Hanna Lindqvist, Søren Krogh Jensen, Nilla Nilsdotter-Linde, Anne-Maj Gustavsson

IGC Proceedings (1977-2023)

Forage is a major source of natural α-tocopherol and β-carotene for dairy cows. This study examined vitamin concentrations of birdsfoot trefoil (Bft), red clover (Rc), timothy (Ti) and meadow fescue (Mf) at different sites, years and cutting dates. Mixtures of Bft+Ti, Rc+Ti and Rc+Mf were established at Skara (58°21’N; 13°08’E) and Umeå (63°45’N; 20°17’E) in Sweden. First-year leys were cut on three occasions in spring (Umeå 2005, Skara 2005 and 2007); one week before heading of timothy, at heading and one week after heading. Birdsfoot trefoil had higher α-tocopherol concentration at Skara than at Umeå in the first two cuts …


Comparing Drying Protocols For Perennial Ryegrass Samples In Preparation For Chemical Analysis, Marion Beecher, Deirdre Hennessy, Tommy M. Boland, Michael O’Donovan, Eva Lewis Jan 2020

Comparing Drying Protocols For Perennial Ryegrass Samples In Preparation For Chemical Analysis, Marion Beecher, Deirdre Hennessy, Tommy M. Boland, Michael O’Donovan, Eva Lewis

IGC Proceedings (1977-2023)

Diet formulation for animals requires accurate estimation of feed nutritive value. In order to determine the nutritive value of grass, the moisture in the samples must be removed, with minimum damage to cell structure, and then the dried samples milled, prior to chemical analysis. Generally samples are oven dried. The aim of this study was to verify if differing drying protocols gave diverging results when drying grass samples. The drying protocols investigated were 40°C for 48 hours, 60°C for 48 hours and 95°C for 15 hours in forced convection ovens. Four perennial ryegrass samples were cut to 4 cm from …


Remote Sensing Of Pasture Quality, Reddy R. Pullanagari, Robyn A. Dynes, Warren M. King, Ian Yule, Susanne Thulin, Nichola M. Knox, Abel Ramoelo Jan 2020

Remote Sensing Of Pasture Quality, Reddy R. Pullanagari, Robyn A. Dynes, Warren M. King, Ian Yule, Susanne Thulin, Nichola M. Knox, Abel Ramoelo

IGC Proceedings (1977-2023)

Worldwide, farming systems are undergoing significant changes due to economic, environmental and social drivers. Agribusinesses must increasingly deliver products specified in terms of safety, health and quality. Increasing constraints are being placed on them by the market, the community and by government to achieve a financial benefit within social and environmental limits (Dynes et al. 2003).

In order to meet these goals, producers must know the quantity and quality of the inputs into their feeding systems, be able to reliably predict the products and by-products being generated, and have the skills to be able to manage their business accordingly. …


Infrastructure To Improve Beef Business Outcomes In The Queensland Gulf, Kiri C. Broad, Bernie H. English, Rebecca A. Gunther, Emma S. Hegarty, Joe W. Rolfe, Steven G. Bray Jan 2020

Infrastructure To Improve Beef Business Outcomes In The Queensland Gulf, Kiri C. Broad, Bernie H. English, Rebecca A. Gunther, Emma S. Hegarty, Joe W. Rolfe, Steven G. Bray

IGC Proceedings (1977-2023)

There are significant economic and environmental issues impacting on the short and long term viability of family-run breeding enterprises in the Queensland Gulf. Falling cattle prices and increased business costs threaten the social and financial well-being of many beef producers. Set stocking and overgrazing combine to reduce native 3P (productive, palatable and perennial) grass frequency and herd productivity. The Ryan family on Greenhills Station at George-town in the Queensland Gulf embarked on a 5 year water and fencing infrastructure development program aiming to improve pasture utilisation, land condition and long term carrying capacity.


A Technique For Measurement Of Cattle Form Using A Trail 3d Digital Camera, Tamaki Kida, Shigeki Tejima, Toshitaka Uchino, Fumihiko Tanaka Jan 2020

A Technique For Measurement Of Cattle Form Using A Trail 3d Digital Camera, Tamaki Kida, Shigeki Tejima, Toshitaka Uchino, Fumihiko Tanaka

IGC Proceedings (1977-2023)

Measurement of weight and form are important for the management of grazing cattle; however, form measurement is seldom carried out. Recently, use of 3D digital cameras has been increasing, and 3D-technology for reconstruction of 3D pictures has been developed. The measurement of withers and hip height of cattle from 3D pictures using the image-analysis technique has been reported (Kida et al. 2012). However, time and effort are required to obtain 3D images of grazing cattle in pastures.

Here, we examined an automatic photographic technique using a sensor camera.


Modelling Complex Sheep Systems Using Ausfarm, Susan M. Robertson, Michael A. Friend Jan 2020

Modelling Complex Sheep Systems Using Ausfarm, Susan M. Robertson, Michael A. Friend

IGC Proceedings (1977-2023)

Simulation modelling can be a valuable method for extrapolating experimental findings to different weather or management conditions. However, most of the decision support tools which are available for sheep grazing systems, for example GrassGro® (Donnelly et al. 1997), are limited to modelling of relatively simple sheep management. This makes validation of simulations against experimental results difficult where management changes from year to year, and where more complex sheep management is used. This study evaluated the use of the AusFarm® decision support tool (Moore et al. 2007) to model a split-joined sheep system, using different ram breeds against experimental …


Does Targeted Short-Term Grazing Of Lucerne Increase Twinning Rates In Unsynchronised Merino Ewes?, Jessica M. Rummery, Susan M. Robertson, Belinda J. King, Michael A. Friend Jan 2020

Does Targeted Short-Term Grazing Of Lucerne Increase Twinning Rates In Unsynchronised Merino Ewes?, Jessica M. Rummery, Susan M. Robertson, Belinda J. King, Michael A. Friend

IGC Proceedings (1977-2023)

Reproduction is one of the key profit drivers in the sheep industry and increased reproductive output is needed to address the decline in sheep numbers in Australia to maintain supply to export markets (Curtis 2009). Increased nutrition around mating, or ‘flushing’, is a well-known means of increasing twinning rates. Studies using synchronisation methods have shown that short-term (acute) supplementation can increase prolificacy if targeted at days 9-14 of the oestrous cycle (Stewart and Oldham 1986). However, synchronisation involves increased chemical and labour costs, so may not suit extensive production systems. This study aimed to test whether an increase in twinning …


Evaluating Rangeland's Grazing Capacity For Livestock And Wild Herbivores Using The Delta Diet Tool And Gis Technology, Sandra A. Santos, Arnaud L. J. Desbiez, Humberto L. Perotto-Baldivieso, Juliana M. Alvarez Jan 2020

Evaluating Rangeland's Grazing Capacity For Livestock And Wild Herbivores Using The Delta Diet Tool And Gis Technology, Sandra A. Santos, Arnaud L. J. Desbiez, Humberto L. Perotto-Baldivieso, Juliana M. Alvarez

IGC Proceedings (1977-2023)

Rangelands are dynamic and complex systems requiring appropriate adaptive decision-making to calculate grazing capacity integrating livestock and herbivore wildlife. This work describes the development and application of an integrated framework using the microhistological analysis (DeltaDiet tool) to identify key forage used by different herbivores from the same area associated with GIS technology to mapping landscape containing forage productivity and quality information. This study was conducted in a management unit, representative of the Nhecolândia sub-region landscape, Pantanal. During the dry period, representative fecal samples were collected from cows, capybaras and deer grazing in the same management unit for diet analysis, using …


Ftir Analysis Of Bacteria Biomass-Mineral Interactions In Soils, Finola Fung-Khee Jan 2020

Ftir Analysis Of Bacteria Biomass-Mineral Interactions In Soils, Finola Fung-Khee

Dissertations and Theses

Soil organic carbon (SOC) accounts for 70% of the carbon on Earth. It is therefore a key player in global carbon cycling and climate change (Smith et al., 2008). Soil organic matter (SOM) is an important component of organic matter in soils (SOC), and results from biogeochemical process involving net primary producers, soil biomass and soil mineralogy (Horwath and Kuzyakov, 2018). In this study, the interplay between soil bacterial biomass and reactive clay minerals in soils was investigated. The purpose of the research was to shed light into the stabilization of SOC in a bacterial biomass-soil/clay matrix. Soils characterized as …


A Comparison Of High-End Methods For Topographic Modelling Of A Coastal Dune Complex, Chen Suo, Eugene Mcgovern, Alan Gilmer, Conor Cahalane Jan 2020

A Comparison Of High-End Methods For Topographic Modelling Of A Coastal Dune Complex, Chen Suo, Eugene Mcgovern, Alan Gilmer, Conor Cahalane

Articles

In recent years, increasing tourism and development in the coastal dune area of the South East of Ireland have resulted in greater pressure on the environment, resulting in issues including soil erosion, flooding and habitat loss. Topographic mapping across a dune field is important for the development of targeted land management actions that maintain biodiversity and ecological functions. Developments in surveying technology, including LiDAR, terrestrial laser scanners (TLS) and aerial surveying from Remotely Piloted Aircraft Systems (RPAS), have enabled high-resolution and high-accuracy spatial data to be gathered quickly and relatively easily for 3D topographic modelling of a coastal dune complex. …


Interpretive Geologic Maps And Cross Sections For Phelps, Kearney, And Adams Counties In Nebraska, Dana Divine, Leslie M. Howard Jan 2020

Interpretive Geologic Maps And Cross Sections For Phelps, Kearney, And Adams Counties In Nebraska, Dana Divine, Leslie M. Howard

Conservation and Survey Division: Faculty and Staff Publications

Data from thousands of test-hole and well logs were interpreted to improve understanding and management of the High Plains aquifer in a three-county study area adjacent to the Big Bend reach of the Platte River. Five principal conclusions resulted from these interpretations: (1) the extent of Neogene Ogallala deposits beneath the study area is different than previously mapped; (2) a large paleovalley incised into Cretaceous bedrock probably cuts across Kearney and Adams counties and may be the course of the ancestral Platte River prior to formation of the Big Bend; (3) a groundwater mound created by irrigation canals artificially raises …


Paleofloods And Landform Development Influence Carbon Storage In A Humid-Subtropical River Valley, Christopher Lance Stewart Jan 2020

Paleofloods And Landform Development Influence Carbon Storage In A Humid-Subtropical River Valley, Christopher Lance Stewart

Murray State Theses and Dissertations

Floodplains can store large amounts of soil organic carbon (SOC) despite covering a small fraction of the global land area. Since these valley-bottom landforms build through the action of flooding, the century to millennial-scale record of overbank deposition could be important in understanding controls on deep (>30 cm) SOC storage. Yet, the influence of flood history and landform development on carbon content is surprisingly not well known. I use a combined geological and pedological approach to characterize the sedimentation, soil development, and SOC of fluvial terraces along an impounded reach of the humid-subtropical Tennessee River valley, U.S.A. The standardized …


Crop Rotations, Tillage And Cover Crops Influences On Soil Health, Greenhouse Gas Emissions And Farm Profitability, Jasdeep Singh Jan 2020

Crop Rotations, Tillage And Cover Crops Influences On Soil Health, Greenhouse Gas Emissions And Farm Profitability, Jasdeep Singh

Electronic Theses and Dissertations

This study assessed the effects of three levels of crop rotation: [2-yr; corn (Zea mays L.)- soybean (Glycine max L.), 3-yr; corn-soybean-oat (Avena sativa L.) or 4-yr; cornsoybean- oat-winter wheat (Triticum aestivum L.)], two tillage [conventional-till (CT) and no-till (NT)], and two winter cover cropping systems [cover crop (CC) or fallow control (NC)] on soil biochemical and physical properties, greenhouse gas emissions (GHG), microbial community composition, crop yield and farm profitability under silty clay loam soil of south eastern South Dakota. Experimental design was a randomized complete block design in a split-split plot treatment arrangement with four replications. Rotations, tillage …


The Impact Of Subsurface Physical Characteristics On The Effectiveness Of Subsurface Drainage In The Northern Great Plains, Mehmet Emin Budak Jan 2020

The Impact Of Subsurface Physical Characteristics On The Effectiveness Of Subsurface Drainage In The Northern Great Plains, Mehmet Emin Budak

Electronic Theses and Dissertations

World-wide, salinity and sodicity problems are increasing in coastal, irrigated and dryland agricultural systems. Traditional reclamation techniques for saline sodic soils include improving soil drainage by installing subsurface drainage, leaching with high quality water, and applying a source of calcium. However, due to differences in the soil parent material these traditional approach treatments were ineffective in removing sodium and other salts out of the soil profile of South Dakota. Understanding how the surface and subsurface soil characteristics and management interact to affect the sustainability of these systems is the first step in remediation. Each region and soil have a slightly …


Understanding South Dakota Farmers’ Intentions To And Adoption Of Conservation Practices: An Examination Of The Theory Of Planned Behavior, Edem Avemegah Jan 2020

Understanding South Dakota Farmers’ Intentions To And Adoption Of Conservation Practices: An Examination Of The Theory Of Planned Behavior, Edem Avemegah

Electronic Theses and Dissertations

Conservation agriculture practice is a sustainable farming method based on three principle: crop diversification, minimal soil disturbance or movement and permanent or semi-permanent of soil cover. Government and stakeholders within the agricultural sector in the United States are promoting conservation farming practices but limited voluntary adoption still exists among producers at the farm level. This research study investigated the factors that influence the adoption of conservation practices among producers in the eastern and central parts of South Dakota (SD). A modified theory of planned behavior (TPB) is used as a framework alongside socioeconomic and demographic indicators to understand farmers’ current …


Soil Physical And Hydrological Properties, And Greenhouse Gas Emissions Under Integrated Crop-Livestock Agroecosystems, Navdeep Singh Jan 2020

Soil Physical And Hydrological Properties, And Greenhouse Gas Emissions Under Integrated Crop-Livestock Agroecosystems, Navdeep Singh

Electronic Theses and Dissertations

Cover crops (CCs) and grazing play a critical role in successful implementation of the integrated crop-livestock system (ICLS) because they can have a direct impact on soils and greenhouse gas emissions. The objectives of this study were to (i) evaluate the short-term impacts of CCs [grass dominated cover crops (GdC) and legume dominated cover crops (LdC)] and grazed CCs and corn (Zea mays L.) residue under oat (Avena sativa L.)–CC–corn rotation on soil physical and hydrological properties; (ii) quantify the architecture of soil pores using X-ray computed tomography (CT) for soils managed under long-term ICLS, native grazed pasture and corn-soybean …


Phytoremediation Of Saline-Sodic Soils In East Central South Dakota Utilizing Perennial Grass Mixtures, Douglas J. Fiedler Jan 2020

Phytoremediation Of Saline-Sodic Soils In East Central South Dakota Utilizing Perennial Grass Mixtures, Douglas J. Fiedler

Electronic Theses and Dissertations

Several decades of above average precipitation in South Dakota has increased the area of saline and sodic soils, which reduce crop yields and inhibit sensitive plant growth. Saline and sodic soils are difficult to remediate using traditional agricultural crops. Establishing salt tolerant perennial species may restore productivity to salt affected areas. Two perennial grass mixtures (mix 1: slender wheatgrass, beardless wildrye; mix 2: slender wheatgrass, western wheatgrass, green wheatgrass, creeping meadow foxtail) were dormant frost seeded along a topographic gradient in Clark Co., SD. Soils were Forman-Cresbard loam and a Cresbard-Cavour loam with surface electrical conductivity (EC1:1) that …


Correlating The Plant Height Of Wheat With Above-Ground Biomass And Crop Yield Using Drone Imagery And Crop Surface Model, A Case Study From Nepal, U. S. Panday, Nawaraj Shrestha, S. Maharjan, A. K. Pratihast, Shahnawaz, K. L. Shrestha, J. Aryal Jan 2020

Correlating The Plant Height Of Wheat With Above-Ground Biomass And Crop Yield Using Drone Imagery And Crop Surface Model, A Case Study From Nepal, U. S. Panday, Nawaraj Shrestha, S. Maharjan, A. K. Pratihast, Shahnawaz, K. L. Shrestha, J. Aryal

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


2019 Nebraska Water Leaders Academy Final Report, M.E. Burbach, R.M. Joeckel, G.S. Matkin Jan 2020

2019 Nebraska Water Leaders Academy Final Report, M.E. Burbach, R.M. Joeckel, G.S. Matkin

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Corn Response To Wastewater-Recycled Phosphorus Fertilizers, Shane R. Ylagan, Kristofor R. Brye Jan 2020

Corn Response To Wastewater-Recycled Phosphorus Fertilizers, Shane R. Ylagan, Kristofor R. Brye

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

The ability to recycle phosphorus (P) from wastewaters could provide a sustainable, continuous source of P that might also help protect surface water quality from P enrichment. The mineral struvite (MgNH4PO4 · 6H2O) is an understudied material that can be created from P- and nitrogen (N)-containing wastewater and has been shown to have agricultural fertilizer value. The objective of this study was to evaluate the effects of electrochemically precipitated struvite (ECST), chemically precipitated struvite (Crystal Green; CG), diammonium phosphate (DAP), monoammonium phosphate (MAP), rock phosphate (RP), and triple superphosphate (TSP) on corn (Zea mays) response in a greenhouse pot study. …


Microdialysis: A Method For Quantifying In Situ Nitrogen Fluxes In Soil Microsites, Srusti Maddala, Mary C. Savin, Julie A. Stenken, Lisa S. Wood Jan 2020

Microdialysis: A Method For Quantifying In Situ Nitrogen Fluxes In Soil Microsites, Srusti Maddala, Mary C. Savin, Julie A. Stenken, Lisa S. Wood

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

Microdialysis, a diffusion-based sampling technique commonly used in biomedical research, has recently been recognized as a candidate for monitoring chemical changes in the rhizosphere. The information it provides about nutrient diffusion may improve nitrogen use efficiency, leading to enhanced management and success of restoration projects. The objective of this study was to determine the efficacy of microdialysis sampling to quantify the relative recoveries (RR%) of nitrate-N and ammonium-N, the two inorganic nitrogen compounds typically found in soil. The effects of microdialysis flow rate, sample medium concentration, and the presence of both analytes in solution on the relative recoveries obtained from …


Assessing The Climate Water Balance Model’S Ability To Predict Soil Moisture Variability And Species Distribution Of A Forested Watershed In The Northern Cumberland Plateau, Katherine J. Love Jan 2020

Assessing The Climate Water Balance Model’S Ability To Predict Soil Moisture Variability And Species Distribution Of A Forested Watershed In The Northern Cumberland Plateau, Katherine J. Love

Theses and Dissertations--Forestry and Natural Resources

Spatial patterns of moisture and tree species have been studied using environmental gradients, often represented by terrain attributes in GIS. With climate change, GIS terrain variables, which are static as long as the elevation remains unchanged, will not reflect alterations in temperature, water cycle, and atmospheric conditions. In this thesis, the commonly used terrain variables and climate water balance variables were evaluated and compared for their ability to explain soil moisture and tree species distributions in a forested watershed in the Northern Cumberland Plateau. The results suggest that GIS terrain variables generally perform better than climate water balance variables, however, …


The Impact Of Ryegrass On A Fragipan Soil, Keegan Patrick Smith Jan 2020

The Impact Of Ryegrass On A Fragipan Soil, Keegan Patrick Smith

Theses and Dissertations--Plant and Soil Sciences

Fragipans are soil horizons which negatively impact row crop yields due to their cemented nature. Annual ryegrass has been proposed as a cover crop to help remediate these dense horizons. The objectives of this study were to (1) evaluate potential ryegrass root exudates and their ability to solubilize proposed fragipan cementing agents, aluminum (Al), iron (Fe), and silica (Si) in stirred-batch reactor studies; and (2) evaluate annual ryegrass’ ability to remediate the fragipan through an 8-week greenhouse growth study using non-destructive, mini-rhizon samplers installed on soil cores for in situ pore water sampling, and non-invasive soil porosity calculations using X-ray …


Internet Of Things For Sustainable Forestry, Abdul Salam Jan 2020

Internet Of Things For Sustainable Forestry, Abdul Salam

Faculty Publications

Forests and grasslands play an important role in water and air purification, prevention of the soil erosion, and in provision of habitat to wildlife. Internet of Things has a tremendous potential to play a vital role in the forest ecosystem management and stability. The conservation of species and habitats, timber production, prevention of forest soil degradation, forest fire prediction, mitigation, and control can be attained through forest management using Internet of Things. The use and adoption of IoT in forest ecosystem management is challenging due to many factors. Vast geographical areas and limited resources in terms of budget and equipment …


Soil Carbon Dynamics And Greenhouse Gas Emissions In Conservation Tillage Systems At Multiple Scales, Yawen Huang Jan 2020

Soil Carbon Dynamics And Greenhouse Gas Emissions In Conservation Tillage Systems At Multiple Scales, Yawen Huang

Theses and Dissertations--Plant and Soil Sciences

Conservation tillage practices like no-tillage and reduced tillage have been widely implemented worldwide, with expectations they would provide multiple benefits (e.g., yield enhancement and soil carbon sequestration) for food security and climate adaptation and mitigation. However, the adoption of conservation tillage faces both opportunities and challenges. A knowledge gap still exists regarding the effects of conservation tillage on the carbon cycle in agroecosystems. This dissertation reflects a comprehensive evaluation of conservation tillage at multiple scales using an integrated systems approach, a combination of data synthesis, the agriculture ecosystem model, and field observations and measurements. I first conducted a meta-analysis to …


Burning With Potential: Understanding The Relationship Between Biochar And Agriculture Of The Northern Glaciated Plains Ecoregion, Kaitlyn Abrahamson Jan 2020

Burning With Potential: Understanding The Relationship Between Biochar And Agriculture Of The Northern Glaciated Plains Ecoregion, Kaitlyn Abrahamson

Electronic Theses and Dissertations

Achieving global sustainable agriculture is one of the most incredible challenges of this century, yet many continue to try to solve this problem through the development of precision technologies. Biotechnologies, such as biochar, can perform like a precision technology while protecting agricultural land from soil erosion and fertility loss. The Northern Glaciated Plains ecoregion of the United States is little researched in the benefits from the use of biochar through improved soil nutrient capture and water retention, crop health improvements, and yield increases. The study plot has four sections of corn stover biochar and eight sections of control sections. This …


Management Implications Of A Rye Cover Crop On Nutrient Cycling And Soybean Production In Southeast South Dakota: Focus On Rye Seeding Rates And Termination Timing, Benjamin Brockmueller Jan 2020

Management Implications Of A Rye Cover Crop On Nutrient Cycling And Soybean Production In Southeast South Dakota: Focus On Rye Seeding Rates And Termination Timing, Benjamin Brockmueller

Electronic Theses and Dissertations

Winter rye (Secale cereale L.) has become an important cover crop in South Dakota; yet, concerns over negative impacts on cash crop yields is one important limitation to the widespread adoption of winter rye in cropping systems. Two field studies were implemented at the Southeast Research Farm near Beresford, SD investigating the impacts of five seeding rates (0-90 kg ha-1) and termination timings (April 19th- May31st) with the objectives of examining the roles of winter rye management practices on soybean production and yield from nutrient cycling of nitrogen (N) and sulfur (S) in the agroecosystem. Plant, residue, …


Dissolved Organic Matter Movement Across Lake Superior’S Terrestrial-Stream-Coastal Interface, Karl M. Meingast Jan 2020

Dissolved Organic Matter Movement Across Lake Superior’S Terrestrial-Stream-Coastal Interface, Karl M. Meingast

Dissertations, Master's Theses and Master's Reports

Dissolved organic matter (DOM) represents a carbon pool that can be easily translocated between ecosystems with the movement of water. This study examines the controls on DOM quantity and character delivered to Lake Superior primarily during the snowmelt period. We employed long-term stream dissolved organic carbon (DOC) data to determine quantity as well as absorption and fluorescence spectroscopy to analyze DOM structure. Our results indicate that an increasing trend in DOC concentrations, likely driven by decreases in acidity of precipitation, combined with slightly less annual runoff have resulted in relatively constant fluxes of DOM to Lake Superior. Additionally, our study …


The Limits Of Lead (Pb) Phytoextraction And Possibilities Of Phytostabilization In Contaminated Soil: A Critical Review, Sara Perl Egendorf, Peter M. Groffman, Gerry Moore, Zhongqi Cheng Jan 2020

The Limits Of Lead (Pb) Phytoextraction And Possibilities Of Phytostabilization In Contaminated Soil: A Critical Review, Sara Perl Egendorf, Peter M. Groffman, Gerry Moore, Zhongqi Cheng

Advanced Science Research Center

This review article focuses on lead (Pb), one of the most ubiquitous and harmful toxicants found in soil. Our objective is to address misconceptions regarding the ability of plants to uptake Pb through their roots and translocate it to above-ground tissues, and their ability to act as hyperaccumulators and thereby phytoextract Pb. In accordance with a number of cited definitions, we suggest that species capable of Pb phytoextraction can be rated with the following three criteria: (1) root uptake above a nominal threshold of 1,000 mg Pb/kg, (2) bioconcentration factor (BCF or shoot/soil concentration) >1, and (3) translocation factor (TF …