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Articles 1 - 11 of 11

Full-Text Articles in Physical Sciences and Mathematics

United States Midwest Soil And Weather Conditions Influence Anaerobic Potentially Mineralizable Nitrogen, Jason D. Clark, Kristen S. Veum, Fabian G. Fernandez, James J. Camberato, Paul R. Carter, Richard B. Ferguson, David W. Franzen, Daniel E. Kaiser, Newell R. Kitchen, Carrie A.M. Laboski, Emerson D. Nafziger, John E. Sawyer, John F. Shanahan Sep 2019

United States Midwest Soil And Weather Conditions Influence Anaerobic Potentially Mineralizable Nitrogen, Jason D. Clark, Kristen S. Veum, Fabian G. Fernandez, James J. Camberato, Paul R. Carter, Richard B. Ferguson, David W. Franzen, Daniel E. Kaiser, Newell R. Kitchen, Carrie A.M. Laboski, Emerson D. Nafziger, John E. Sawyer, John F. Shanahan

Agronomy, Horticulture and Plant Science Faculty Publications

Nitrogen provided to crops through mineralization is an important factor in N management guidelines. Understanding of the interactive effects of soil and weather conditions on N mineralization needs to be improved. Relationships between anaerobic potentially mineralizable N (PMNan) and soil and weather conditions were evaluated under the contrasting climates of eight US Midwestern states. Soil was sampled (0–30 cm) for PMNan analysis before pre-plant N application (PP0N) and at the V5 development stage from the pre-plant 0 (V50N) and 180 kg N ha−1 (V5180N) rates and incubated for 7, 14, …


Distribution And Productivity Of Naturalized Alfalfa In Mixed-Grass Prairie, Lan Xu, Arvid Boe, Patricia Johnson, Roger N. Gates, Christopher G. Misar Jun 2019

Distribution And Productivity Of Naturalized Alfalfa In Mixed-Grass Prairie, Lan Xu, Arvid Boe, Patricia Johnson, Roger N. Gates, Christopher G. Misar

Natural Resource Management Faculty Publications

Alfalfa (Medicago sativa L.) is an important forage and conservation crop in North America but occurrences of naturalized alfalfa in rangelands are rare. A naturalized population of yellow-flowered alfalfa in mixed-grass prairie on the Grand River National Grassland in South Dakota has potential agricultural value for the region. Despite this value, the distribution pattern of this alfalfa among and within native plant communities in the northern Great Plains is unknown. Field studies were conducted from 2003 through 2006 along topographic positions at two sites where yellow-flowered alfalfa was naturalized to evaluate the relationships of yellow-flowered alfalfa on biomass production, cover, …


Chemical Amendments Of Dryland Saline–Sodic Soils Did Not Enhance Productivity And Soil Health In Fields Without Effective Drainage, Girma A. Birru, David E. Clay, Thomas M. Desutter, Cheryl L. Reese, Ann C. Kennedy, Sharon A. Clay, Stephanie A. Bruggeman, Rachel K. Owen, Douglas D. Malo Apr 2019

Chemical Amendments Of Dryland Saline–Sodic Soils Did Not Enhance Productivity And Soil Health In Fields Without Effective Drainage, Girma A. Birru, David E. Clay, Thomas M. Desutter, Cheryl L. Reese, Ann C. Kennedy, Sharon A. Clay, Stephanie A. Bruggeman, Rachel K. Owen, Douglas D. Malo

Agronomy, Horticulture and Plant Science Faculty Publications

A common restoration treatment for saline–sodic soils involves improving soil drainage, applying soil amendments (e.g., CaSO4, CaCl2, or elemental S), and leaching with water that has a relatively low electrical conductivity. However, due to high subsoil bulk densities and low drainable porosities, these treatments many not be effective in glaciated dryland systems. A 3-yr field study conducted in three model systems determined the impact of chemical amendments (none, CaCl2, CaSO4, and elemental S) on plant growth, microbial composition, temporal changes in electrical conductivity (ECe ), and the relative sodium content (%Na). …


Soil And Land- Use Change Sustainability In The Northern Great Plains Of The Usa, Deepak Raj Joshi, David E. Clay, Alexander Smart, Sharon A. Clay, Tulsi P. Kharel, Umakanta Mishra Mar 2019

Soil And Land- Use Change Sustainability In The Northern Great Plains Of The Usa, Deepak Raj Joshi, David E. Clay, Alexander Smart, Sharon A. Clay, Tulsi P. Kharel, Umakanta Mishra

Agronomy, Horticulture and Plant Science Faculty Publications

In the Northern Great Plains (NGP), the combined impacts of land-use and climate variability have the potential to place many soils on the tipping point of sustainability. The objectives of this study were to assess if the conversion of grassland to croplands occurred on fragile landscapes in the North America Northern Great Plains. South Dakota and Nebraska were selected for this study because they are located in a climate transition zone. We visually classified 43,200 and 38,400 points in South Dakota and Nebraska, respectively, from high-resolution imagery in 2006, 2012, and 2014 into five different categories (cropland, grassland, habitat, NonAg, …


Understanding Greenhouse Gases, Julie M. Mueller, Laura Edwards, Madhav P. Nepal, Larry B. Browning, Matthew L. Miller, P. Troy White Jan 2019

Understanding Greenhouse Gases, Julie M. Mueller, Laura Edwards, Madhav P. Nepal, Larry B. Browning, Matthew L. Miller, P. Troy White

iLEARN Teaching Resources

Students will conduct hands-on experiments to see how greenhouse gases interact with the Earth’s atmosphere and how greenhouse gases affect temperature. This lesson introduces National Geographic’s Geo-Inquiry Process, where students will identify a Geo-inquiry question, collect data, and create a project around the answer to their question. Students will then present their findings to their peers and evaluate their Geo-Inquiry process.


Brassica Carinata Growth And Yield Response To Nitrogen And Sulfur Fertilizers And Impacts On Selected Soil Parameters And Ghg Fluxes, Dwarika Bhattarai Jan 2019

Brassica Carinata Growth And Yield Response To Nitrogen And Sulfur Fertilizers And Impacts On Selected Soil Parameters And Ghg Fluxes, Dwarika Bhattarai

Electronic Theses and Dissertations

Carinata (Brassica carinata A. Braun), a non-food oilseed crop and an alternative bio-jet fuel feedstock, has received attention for its potential as a low-input option for production in the semi-arid regions of the Northern Great Plains of USA. The crop has a lower N fertilizer requirement as compared to the other oilseeds, suggesting less negative impact on soils and GHGs emissions. Carinata is a new crop to South Dakota (SD), thus, the best management practices have yet to be developed. In addition, no sufficient research to address the impact of growing carinata on soils and GHG emissions has been …


Estimating Soil Organic Carbon In Cultivated Soils Using Soil Test Data, Remote Sensing Imagery From Satellites (Landsat 8 And Plantscope), And Web Soil Survey Data, Muhammed Halil Koparan Jan 2019

Estimating Soil Organic Carbon In Cultivated Soils Using Soil Test Data, Remote Sensing Imagery From Satellites (Landsat 8 And Plantscope), And Web Soil Survey Data, Muhammed Halil Koparan

Electronic Theses and Dissertations

Soil organic carbon (SOC) is an important soil parameter of cultivated soils that needs to be monitored and mapped regularly to enhance soil health and productivity. SOC levels in cultivated areas is difficult to monitor for farmers and is costly to analyze using traditional methods. The objective of this study was to estimate surface SOC distribution in selected soils of Major Land Resource Areas (MLRA) 102A (Rolling Till Plain, Brookings County, SD) and 103 (Central Iowa and Minnesota Till Prairies, Lac qui Parle County, MN) using soil sample data, Web Soil Survey (WSS) data, and satellite imagery (Landsat 8 and …


Mob Grazing Results In High Forage Utilization And Reduced Western Snowberry Size, Heidi Reed, Sharon Clay, Alexander Smart, David Clay, Michelle Ohrtman Jan 2019

Mob Grazing Results In High Forage Utilization And Reduced Western Snowberry Size, Heidi Reed, Sharon Clay, Alexander Smart, David Clay, Michelle Ohrtman

Agronomy, Horticulture and Plant Science Faculty Publications

Mob-grazing strives to maximize forage utilization and minimize selective grazing by using high stocking densities in small paddocks for short durations (12–24 hr). Rotational-grazing uses low stocking densities for a longer time period, retaining about half of the original available forage; although selective grazing can occur. Three cattle (Bos taurus × Bos indicus) grazing intensities: mob- (stocking densities from 32,000 to 67,000 kg ha−1; duration—24 hr); rotation (stocking density—2500 kg ha−1; duration—35 d); and non-grazed systems were compared based on forage utilization and changes to western snowberry (Symphoricarpos occidentalis) (WS) patch volume in a 2-year South Dakota study. …


Long-Term Impacts Of Manure And Inorganic Fertilization On Soil Physical, Chemical And Biological Properties, Asmita Gautam Jan 2019

Long-Term Impacts Of Manure And Inorganic Fertilization On Soil Physical, Chemical And Biological Properties, Asmita Gautam

Electronic Theses and Dissertations

The intensive use of mineral fertilizers to achieve high crop yield has led to soil degradation and poor soil health. Thus, manure application as an alternative to mineral fertilizers can be an effective fertilization strategy to improve soil health and biodiversity. This study aims to assess the impacts of long-term manure and mineral fertilizers on soil physical, chemical and biological properties. The experimental site was initiated in 2003 near Beresford, South Dakota on Egan soil under a randomized complete block design with four replications and six treatments. The study treatments included: three manure rates [low manure (LM), manure application based …


Diversifying Cornfields By Interseeding Cover Crops: Practical Implications And The Response Of Invertebrate Communities, Michael Bredeson Jan 2019

Diversifying Cornfields By Interseeding Cover Crops: Practical Implications And The Response Of Invertebrate Communities, Michael Bredeson

Electronic Theses and Dissertations

The lack of suitable habitat conditions for beneficial organisms in simplified agroecosystems leads to unstable invertebrate communities and overreliance on chemical control of herbivores. It is possible to manage pest populations without agrichemicals by manipulating farmland so that herbivores are impaired by plant-driven bottom-up and enemy-driven top-down antagonisms. Interseeding cover crops between established crop rows is a method used by farmers to improve habitat suitability for natural enemies and hinder host-finding, feeding and movement by herbivores. Here I address three important research gaps related to interseeding cover crops. A calcium carbonate seed coating, used to improve seed-broadcasting efficiency, was tested …


Isolation And Identification Of Potential Bioinoculants Based On Phosphate Solubilizing And Plant Growth Promoting Benefits, Rachel Raths Jan 2019

Isolation And Identification Of Potential Bioinoculants Based On Phosphate Solubilizing And Plant Growth Promoting Benefits, Rachel Raths

Electronic Theses and Dissertations

Conservative models have shown that as populations rise, food production needs to double by 2050. Population increase and the green revolution have caused fertilizer inputs to increase since the 1960’s, increasing environmental issues and production costs. These intensive practices have led to degraded arable land and there has been an increase in urbanization meaning we need to make best use of the farming land that is available and ensure it is sustainable for future food production. Due to this, there has been a higher demand for research on more environmentally and economically friendly approaches to food production. Plant growth promoting …