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Effects Of Soil Management Practices On Water Infiltration And Maize Yield To Improve Mississippi River Valley Alluvial Aquifer Sustainability, Jacob Rix
Theses and Dissertations
Surface sealing and hardpans in loam soils are problematic in the Mid-South U.S. because of intense tillage. Two experiments quantified the effects of soil management practices on infiltration and maize yield in loam soils. The first study measured the impacts of in-row subsoiling frequency × furrow irrigation frequency. In-row subsoiling significantly improved the infiltration of irrigation but not the infiltration of precipitation. In-row subsoiling with low irrigation frequency is optimal to achieve profitable maize yields while encouraging groundwater conservation. In the second study, six soil management treatments were imposed. For single-ring infiltrometer tests, infiltration rates were different between the two …
Evaluation Of Alternate Wetting And Drying Irrigation Management In Rice, Richard Lee Atwill Ii
Evaluation Of Alternate Wetting And Drying Irrigation Management In Rice, Richard Lee Atwill Ii
Theses and Dissertations
Water level declines in the Mississippi River Valley Alluvial Aquifer (MRVAA) are attributed largely to withdrawals for rice (Oryza sativa L.) irrigation. This study was performed to determine if alternative irrigation strategies for rice could reduce withdrawal from the MRVAA without having an adverse effect on grain yield, grain quality, control of barnyardgrass, and profitability. Research was conducted in Stoneville, MS and 19 on-farm locations across the Delta region of Mississippi from 2014 through 2017 to determine the irrigation threshold for alternate wetting and drying (AWD) rice irrigation, the effect of AWD management on barnyardgrass control, and effects of …
Analysis Of Surface Water For Irrigation In The Big Sunflower River Watershed, Meredith Lynn Brock
Analysis Of Surface Water For Irrigation In The Big Sunflower River Watershed, Meredith Lynn Brock
Theses and Dissertations
Exploitation of groundwater and excess nutrient runoff are major issues plaguing agriculture and streams in the Lower Mississippi River Basin, and increased irrigation intensity has yielded a proportionate increase in water use. Quantifying the use and effects of conservation practices like on-farm water storage (OFWS) systems will justify continued adoption of these practices to mitigate groundwater decline and nutrient runoff. Since 2010, over 795 hectares of surface water storage has been added in the Big Sunflower River Watershed, and analysis of aquifer saturation shows a recent rise in the water table and a decrease in seasonal water table drawdowns. Modeling …
Understanding In-Field Soil Moisture Variability And Associated Impact On Irrigation, Blade Hodges
Understanding In-Field Soil Moisture Variability And Associated Impact On Irrigation, Blade Hodges
Theses and Dissertations
Site-specific irrigation decisions require information about variations in soil moisture within the rooting depth actively being used by the crop. Producers have been using soil moisture sensors to make irrigation decisions, and it has been shown that soil moisture sensors can reduce water usage without reducing yields. There are still unanswered questions on improving efficiency with soil moisture sensors based on density and location of sensors within a field. This three-year study uses sensors to evaluate the spatio-temporal variability of soil moisture across an 18-ha production field in a corn/soybean rotation. The IDW results show that when uniform irrigation applications …
Drought-Tolerant And Short-Season Corn Hybrids To Mitigate Risk, Optimize Yield And Profit, While Increasing Water Use Efficiency, John Joseph Williams
Drought-Tolerant And Short-Season Corn Hybrids To Mitigate Risk, Optimize Yield And Profit, While Increasing Water Use Efficiency, John Joseph Williams
Theses and Dissertations
The Mississippi River Valley Alluvial Aquifer (MRVAA) aquifer is the principal water source for Mid-South irrigators, but the current rate of withdrawal from the aquifer is not sustainable. Means to increase the sustainability of the MRVAA is to improve corn’s water use efficiency (WUE) while, concurrently, maintaining or improving profitability. The objectives of this experiment were to determine the effects of sensor-based irrigation threshold, planting date, and hybrid on corn grain yield, WUE, and net returns above seed and irrigation cost. Season long irrigation thresholds of -50 kPa full irrigation (FI) and -125 kPa limited irrigation (LI) were used, utilizing …
Phosphorus Occurrence And Origin In The Mississippi River Valley Alluvial Aquifer In Northwestern Mississippi, Claire Elise Rose
Phosphorus Occurrence And Origin In The Mississippi River Valley Alluvial Aquifer In Northwestern Mississippi, Claire Elise Rose
Theses and Dissertations
The median total dissolved phosphorus concentration (0.41 mg/L P) of groundwater from the Mississippi River Valley alluvial aquifer exceeded the U.S. Environmental Protection Agency’s stream nutrient criteria (of 0.1 mg/L P) and the national background for phosphorus in groundwater (0.02 mg/L P). A general association between elevated phosphorus and dissolved iron concentrations suggests that reducing conditions that mobilize iron in the aquifer also may facilitate transport of phosphorus. These elevated concentrations of phosphorus may indicate phosphorus in the study area may be concentrated through irrigation return flow and groundwater discharge, and may contribute to the Gulf of Mexico hypoxic zone. …
Evaluation Of An On-Farm Water Storage System As A Bmp For Sediment And Nutrient Reduction, Nutrient Recycling, And Irrigation In East Mississippi, Ritesh Karki
Theses and Dissertations
Evaluation of an On-Farm Water Storage (OFWS) system as a Best Management Practice (BMP) for nutrient and sediment loading control and irrigation in East Mississippi has shown that the system can effectively reduce sediment and nutrient loading as it was able to capture 46 tons of sediment and 558 kg of phosphorus over the monitoring period. The system was also able to decrease nitrogen loading as shown from the nitrogen concentration in the captured storm runoff events although an accurate estimate could not be made using AnnAGNPS because adequate model input data was not available. The system was able to …
Methodology To Predict Daily Groundwater Levels By The Implementation Of Machine Learning And Crop Models, Sandra Milena Guzman Gutierrez
Methodology To Predict Daily Groundwater Levels By The Implementation Of Machine Learning And Crop Models, Sandra Milena Guzman Gutierrez
Theses and Dissertations
The continuous decline of groundwater levels caused by variations in climatic conditions and crop water demands is an increased concern for the agricultural community. It is necessary to understand the factors that control these changes in groundwater levels so that we can better address declines and develop improved conservation practices that will lead to a more sustainable use of water. In this study, two machine learning techniques namely support vector regression (SVR) and the nonlinear autoregressive with exogenous inputs (NARX) neural network were implemented to predict daily groundwater levels in a well located in the Mississippi Delta Region (MDR). Results …
Impact Of Irrigation Applications At Soil Moisture Deficits On Plant Development And Yield Of Indeterminate And Determinate Soybean Varieties, Andy J. Brown
Theses and Dissertations
As the Mississippi River Alluvial Aquifer declines, it is the duty of soybean producers to become more efficient irrigators. Research was established in 2012 and 2013 in the Mississippi Delta to evaluate plant development and yield of an indeterminate soybean variety with irrigation initiated at the R1 producer standard and compared to initiation timings at the R2, R4, and R5 growth stages once a 2” deficit was reached according to the FAO-56 Penman-Monteith model. Research was also conducted to evaluate seeding rates in irrigated and non-irrigated systems in Starkville and Stoneville, MS in 2013 and 2014. These data indicate that …
Impact Of Irrigation, Leaf Pubescence, And Week Of Flowering On The Effect Of Tarnished Plant Bug On Cotton Yields, Clinton Wilks Wood
Impact Of Irrigation, Leaf Pubescence, And Week Of Flowering On The Effect Of Tarnished Plant Bug On Cotton Yields, Clinton Wilks Wood
Theses and Dissertations
The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is the most important insect pest of cotton, Gossypium hirsutum (L.), in Mississippi. This research project was initiated to gain a better understanding of selected crop production factors that can improve tarnished plant bug integrated pest management. Results suggest that irrigation strategies and varietal pubescence can significantly influence tarnished plant bug management in cotton. Most notably, delaying irrigation for as long as possible and planting hairy varieties can minimize the impact of tarnished plant bug on cotton yields and reduce the number of insecticides needed to manage this pest. Additionally, these …
Evaluation Of Water And Nitrogen Management Practices In Southern Us Rice (Oryza Sativa L.) Production, Richard Lee Atwill
Evaluation Of Water And Nitrogen Management Practices In Southern Us Rice (Oryza Sativa L.) Production, Richard Lee Atwill
Theses and Dissertations
Nitrogen (N) fertility and irrigation costs are the greatest input expenses required for rice production in Mississippi, therefore N management and irrigation should be conducted in efficiently. Field experiments were conducted at the Delta Research and Extension Center in Stoneville, MS, and the LSU AgCenter in Crowley, LA, to evaluate water and nitrogen management practices. Nitrogen use efficiency and yield were not different for alternate wetting and drying (AWD) systems compared to a traditional continuous flood. Additionally, experiments were conducted to test for differences comparing two experimental designs, randomized complete block (RCB) and split-plot (SP), for N-rate response trials in …
Modeling Effects Of Climatological Variability And Management Practices On Conservation Of Groundwater From The Mississippi River Valley Shallow Alluvial Aquifer In The Mississippi Delta Region, Robert Frank Thornton
Modeling Effects Of Climatological Variability And Management Practices On Conservation Of Groundwater From The Mississippi River Valley Shallow Alluvial Aquifer In The Mississippi Delta Region, Robert Frank Thornton
Theses and Dissertations
Ninety-eight percent of water taken from the Mississippi River Shallow Alluvial Aquifer, hereafter referred to as “the aquifer” or “MRVA,” is used by the agricultural industry for irrigation. Mississippi Delta agriculture is increasingly using more water from the MRVA and the aquifer has been losing about 300,000 acreeet per year. This research expands on previous work in which a model was developed that simulates the effects of climatic variability, crop acreage changes, and specific irrigation methods on consequent variations in the water volume of the MRVA. This study corrects an identified problem by replacing total growing season precipitation with an …