Location: Soil Drainage Research2012 Annual Report
1a. Objectives (from AD-416):
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.
1b. Approach (from AD-416):
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.
3. Progress Report:
A fourth year of data collection, continuing from the preceding expired project 3604-13000-008-00D, is underway at a field research facility in northwest Ohio that is fully instrumented to compare restricted (controlled) subsurface drainage versus conventional, unrestricted subsurface drainage with respect to differences in crop yield, discharged drainage water quality, drainage water discharge volume, and shallow water table response. Data collected at this site is also being utilized to improve design criteria for subsurface drainage systems. Three previous years of comparison data have now been fully tabulated. Drain flow volume, drainage water quality, precipitation, and crop yield data collection also continued at eight on-farm paired fields comparing the application of restricted drainage to conventional drainage. Ground penetrating radar (GPR) integrated with real-time kinematic (RTK) Global Positioning System (GPS) technologies has been tested at six golf course sites in Ohio for the purpose of mapping subsurface drainage pipe systems and soil layer thicknesses. An equipment sled, to be towed behind an all terrain vehicle, has been designed and constructed so that GPR-RTK/GPS surveys can be carried out on farm fields to map buried drainage pipe networks. Laboratory testing results are now being evaluated with respect to the soil water content impact on the anion exclusion processes that in turn affect nitrate mobility in saturated and unsaturated soil. A laboratory testing program evaluated four iron-based filter materials for water treatment of phosphate and organochloride pesticides (2,4-D, alachlor, and atrazine). Field research sites established at Hoytville and Piketon, OH, for evaluation of innovative agronomic management systems including cover crops and gypsum soil amendments. Soil samples for baseline physical and biological assessment acquired, and cropping sequences initiated. Fifty lines of wild soybean (Glycine soja) and the 50 parental lines of the Nested Association Mapping (NAM) population planted to repeat flooding trials conducted in 2011. Laboratory study initiated to determine varietal differences for manganese toxicity thresholds.
1. Four iron-based filter materials evaluated for phosphate and organochloride pesticide water treatment. Phosphate and organochloride pesticides released into the environment from farm fields can degrade ground and surface waters. Filter treatment systems containing iron-based materials can potentially remove these agricultural contaminants from water. A laboratory study (hydraulic conductivity, batch, and column experiments) was therefore conducted to evaluate the phosphate and organochloride pesticide (2,4-D, alachlor, and atrazine) removal capabilities of four iron-based filter materials. The four iron-based filter materials evaluated were a zero valent iron (ZVI), a porous iron composite (PIC), a sulfur modified iron (SMI), and an iron oxide/hydroxide. Results indicate that each of the four iron based filter materials can remove substantial amounts of phosphate, even with high initial phosphate concentrations and high water flow rates. Furthermore, PIC was found to work extremely well by quickly removing almost all 2,4-D, alachlor, and atrazine initially present at high concentrations. Consequently, filter systems containing iron-based materials may be feasible for treatment of agricultural waters containing phosphate and organochloride pesticides, thereby providing environmental and health benefits to the public.
2. Soybean seed quality index (SQI) developed. In order to effectively compare the response of soybean seed quality to flooding stress in different environments, we developed the Seed Quality Index (SQI), the single composite integrator of seed quality based on protein, oil, oleic acid, linoleic acid, linolenic acid, and isoflavones content. We found that SQI increased in the flood-tolerant plant introductions in response to flooding stress, but decreased in the flood-susceptible check cultivar Williams. Soybean breeders can use this information to assist in the development of new varieties to meet specific nutritional and alternative energy goals.
3. Innovative agronomic management system established to improve yield and soil quality in soybean production systems. Research trials were initiated on four University research farms in Alabama, Indiana, and Ohio to examine the combined effects of no-till, cover crop, and gypsum soil amendment on production, economic efficiency, and soil quality parameters. Demonstration plots were also initiated at Farm Show locations in Iowa, Ohio, and Pennsylvania to expose this system to soybean growers. Documenting the performance of this system will be important in developing food security and sustainability guidance for growers.
Allred, B.J. 2011. Laboratory evaluation of zero valent iron and sulfur modified iron filter materials for agricultural drainage water treatment. Ground Water Monitoring and Remediation. 32(2):80-95. DOI: 10.1111/j.1745-6592.2011.01379.x.