Project Number: 3604-13000-010-00
Project Type: Appropriated

Start Date: Dec 22, 2011
End Date: Dec 21, 2016

Objective:
Objective 1 - Improve drainage water management practices through advancement in design and operational criteria, testing and modification of proximal soil sensing tools, better understanding of important nutrient transport processes in poorly drained soils, and development of innovative on-site drainage water treatment technologies. Sub-Objective 1a - Develop subsurface drainage water management system design and operational criteria that optimize environmental protection and crop production. I) Field research at Defiance Agricultural Research Association (DARA) site using different system design and water table management strategies. II) Collect, summarize, and interpret data from paired field experiments on private farms to compare the economic and environmental performance of unrestricted and restricted subsurface drainage treatments, and utilize the information to develop operating and maintenance guidelines for growers, crop advisors, and farm managers. Sub-Objective 1b - Evaluate/refine proximal soil sensing methods for use as tools to enhance the practice of subsurface drainage water management. Activities will include the following. I) Evaluation of near-surface geophysical methods to locate/assess subsurface drainage system infrastructure. II) Capability assessment of near-surface geophysical methods to provide valuable information needed for drainage system design. Sub-Objective 1c - Delineate and quantify important transport processes affecting nitrate (NO3-) mobility within poorly drained soils common throughout the Midwest U.S. I) Determination of soil water content effects on NO3- anion exclusion processes. II) Laboratory quantification of anion exclusion impacts on NO3- movement in a variety of poorly drained Midwest U.S. soils typically requiring subsurface drainage. III) Development of a soil NO3- transport semi-analytical model incorporating anion exclusion. Sub-Objective 1d - Develop effective and efficient filter treatment systems capable of removing nutrients and pesticides from waters discharged by small- and large-scale subsurface drainage systems. Objective 2 - Develop flooding tolerant crop cultivars and evaluate new agronomic practices to enhance agricultural sustainability and environmental protection for poorly drained soils in the Midwest U.S. Subobjective 2a - Evaluate no-till, soil amendment, and cover crop practices as compared to conventional management practices improving crop yield and soil/water quality in intermittently wet soils. Subobjective 2b - Identify the critical levels of microelement toxicity in soybeans and characterize the association of tolerance of microelement toxicity and tolerance of flooding in soybeans. Characterize soybean germplasm tolerant to flooding and element toxicities associated with intermittently wet soils.

Approach:
1a: Two separate field research studies. Based on similarity of subsurface drainage system infrastructure characteristics, there are a total of four replicated pairs of subplots. 1b:Ground penetrating radar (GPR) will be integrated with real-time kinematic (RTK) Global Positioning System (GPS) roving receivers and a continuously operated GPS reference station network to effectively and efficiently map buried drainage pipe networks on both small and large scales. 1c: Replicated transient, unsaturated horizontal column experiments have been used to quantify the effects on soil NO3- anion adsorption/exclusion due to clay mineralogy, soil solution ionic strength, and the type of dominant exchangeable cation present. Additional replicated transient unsaturated horizontal column experiments, approximately 20 in total, will be conducted on a typical Midwest U.S. soil to evaluate soil water content impacts on NO3- anion exclusion. 1d: Further laboratory investigation will be carried out to evaluate contaminant removal abilities for improved formulations of these porous iron-based materials, especially in regard to a wider range of pesticides (alachlor, atrazine, and 2,4-D). (Note: Laboratory determination of porous iron-based filter material effectiveness and efficiency will be established though the ability to maintain a sufficiently high hydraulic conductivity, the percent/amount of contaminant removal, and the longevity with respect to contaminant removal.) 2a: We will conduct field experiments at two locations in Ohio (Columbus and Piketon) to test the efficacy of no-tillage with (1) cover crops (cereal rye grass and oil seed radish in rotation) versus no cover crops. Oilseed radish (2 kg/ha), Alaskan winter pea (25 kg/ha), and cereal rye (13 kg/ha) will be planted as cover crops immediately after harvesting soybean; and (2) mined gypsum versus FGD gypsum and no gypsum on the tolerance of soybeans to flooding. 2b: To assess soybean tolerance to microelement toxicity, an experiment will be conducted in the growth chamber using the growth-pouch technique.