Project : USDA ARS

ARS Home » Southeast Area » Florence, South Carolina » Coastal Plain Soil, Water and Plant Conservation Research » Research » Research Project #431207

Research Project: Improvement of Soil Management Practices and Manure Treatment/Handling Systems of the Southern Coastal Plain

Location: Coastal Plain Soil, Water and Plant Conservation Research

2021 Annual Report

Objectives
1. Develop and test improved tillage and biomass management practices to enhance soil health and long-term agricultural productivity in the Southeastern Coastal Plain. 2. Develop manure treatment and handling systems that improve soil health and water quality while minimizing the emissions of greenhouse gases, odors and ammonia and the transport of phosphorus and pathogens. Subobjective 2a. Develop improved treatment systems and methods for ammonia and phosphorus recovery from liquid and solid wastes using gas-permeable membrane technology. Subobjective 2b. Develop improved biological treatment systems for liquid effluents and soils based on deammonification reaction using ARS patented bacterial anammox and high performance nitrifying sludge cultures. Subobjective 2c. Improve the ARS patented “Quick Wash” process for phosphorus recovery. Subobjective 2d. Assess treatment methods for their ability to reduce or eliminate pathogens and cell-free, microbially-derived DNA from agricultural waste streams. Subobjective 2e. Improved manure treatment and handling systems, and management strategies for minimizing emissions. Subobjective 2f. Assess the impact of manure treatment and handling systems on agricultural ecosystem services for soil, water, and air quality conservation and protection. 3. Develop beneficial uses of agricultural, industrial, and municipal byproducts, including manure. Subobjective 3a. Evaluate application of designer biochars to soils to increase crop yields while improving soil health, increasing carbon sequestration, and reducing greenhouse gas emissions. Subobjective 3b. Develop methods and guidelines to remediate mine soils using designer biochars. Subobjective 3c. Evaluate the agronomic value of byproducts produced from emerging manure and municipal waste treatment technologies.

Approach
New management practices and treatment technologies are required to help the nation’s crop and animal producers meet increasing economic and environmental challenges. These challenges include increasing soil productivity and health, as well as reducing unwanted atmospheric emissions, excessive nutrients, pathogens, and odors while concomitantly improving the affordability of animal waste treatment. To solve these challenges this research will pursue three complementary objectives. First, improved tillage and biomass management practices will be developed to enhance soil health and long-term agricultural productivity for Southeastern Coastal Plain soils. Long-term conservation tillage and crop management practices, including stover management and cover crops, will be evaluated to enhance soil productivity and limit the impact of climate change while enhancing nutrient cycling and carbon sequestration. Second, new manure treatment and handling technologies will be developed to improve soil health and water quality; to minimize emissions of greenhouse gases, odors, ammonia, and pathogens; and to maximize nutrient recovery. These technologies include: recovery of ammonia from manure using gas permeable membranes, enhanced biological nitrogen treatment via deammonification, biochar systems engineered to reduce odor, and new and improved methods of recovering phosphorus from manure. This research project will include covered anaerobic lagoons, thermal treatment, and acidification as technologies to reduce or destroy manure pathogens prior to land application. Third, we will develop beneficial uses for byproducts of manure treatments. This includes the use of biochars and hydrochars byproducts as soil amendments to improve physical and chemical properties, and as a fertilizer source for crop production. Research methods include laboratory, pilot-scale, and field-scale experiments using modern analytical equipment. Research products will advance the state of the science for more effective conservation and management of soil resources, innovative animal waste treatment technologies as environmentally-safe alternatives to traditional land application, and guidelines for beneficial byproduct utilization. Nationwide livestock producers, as well as Southeastern crop producers, will benefit from the findings of this research.

Progress Report
This project reached its term date and it was continued through a bridging project pending the completion review and implementation of the Location’s new 212 National Program Project. The results from this project advanced the state of the science for improved tillage and biomass management practices to improve soil health and agricultural productivity, animal waste treatment technologies, and beneficial uses of manure byproducts. The research of this project has been reported in 71 peer reviewed articles, 4 book chapters, and 5 U.S. Patents. Project summary report: 1) Develop and test improved tillage and biomass management practices to enhance soil health and long-term agricultural productivity in the Southeastern Coastal Plain. -Conservation tillage was documented to rebuild surface soil organic carbon (SOC) and nitrogen (N) contents. In sandy Coastal Plains top-soils, long-term (37 years) conservation tillage promoted a significant increase of 23 and 16% (24.7 and 2.3 Mg ha-1) of SOC and total N contents, respectively, compared to topsoil values under conventional tillage (20.0 and 2.0 Mg ha-1). We showed that the accumulation of SOC eventually reaches a saturation point where adding more crop residue doesn’t correspond to a joint increase in SOC. 2) Develop manure treatment and handling systems that improve soil health and water quality while minimizing the emissions of greenhouse gases, odors and ammonia and the transport of phosphorus and pathogens. -Novel anammox bacterium isolate for purification and recycling wastewater: A novel anammox bacterium isolate Brocadia caroliniensis (NRRL B-50286) was discovered using manures that thrives in high-ammonia environments. The anaerobic ammonium oxidation process (anammox) converts ammonia (NH3) and nitrite to dinitrogen gas under anaerobic conditions and provides a more energy-efficient alternative to conventional N removal systems. -Recovery of NH3 from wastes using gas-permeable membranes: A new technology was invented to recover gaseous ammonia from wastes using gas permeable membranes. The new process includes the passive passage of NH3 through micro-porous hydrophobic membranes and subsequent concentration in a clear fertilizer solution. The technology can be applied to N capture from liquid manure and N capture inside the barns. -Production of high-grade phosphates from animal effluents. New technologies were invented allowing separation and concentration of phosphorus (P) from animal effluents. It eliminates carbonate and NH3 buffers using biological means (nitrification with high performance nitrifying bacteria) or using physical means (gas-permeable membranes), yielding very-high phosphate grade products. -Innovative manure treatment reduces nutrient pollution and creates commercial products. Excess P found in manure applied as crop fertilizer can contaminate rivers, lakes, and bays through runoff. Researchers in ARS Florence, South Carolina, developed a new biorefinery process that recovers value-added P, proteins, amino acids, and leftover solids from manures. The process is more efficient by combining manure with wastes that contain sugars as acid precursors. -Recovery of calcium phosphates from swine lagoon sludge. The Quick Wash (QW) process developed by scientists at ARS Florence, South Carolina, uses a novel combination of acid, base, and organic polyelectrolytes to selectively extract and recover P from solid wastes. The QW process was combined with a geotextile bag dewatering in a system to extract and recover P from swine lagoon sludges. Products obtained had higher concentrations of P (33.2 to 35.5 % P2O5) than rock phosphate. -A vegetative environmental buffer (VEB) surrounding a broiler house removed 22% of NH3 emission and reduced downwind concentration due to dispersion. The NH3 removal by the VEB was estimated by the difference between the NH3 emission rates before and after the VEB using a backward Lagrangean stochastic inverse dispersion technique. -A commercial biochar made from pine chips was evaluated for its efficacy of removing malodor compounds and hydrogen sulfide using a pilot-scale biochar odor removal system (PSBORS) by placing it in a nursery pen continually treating the indoor air for 21 days. The results showed that the biochar was effective to reduce the concentration of hydrogen sulfide and all odorous compounds in the PSBORS effluent below their detection limits except for acetic acid. - Developed and tested hydrothermal carbonization (HTC) methods to determine pathogen antimicrobial resistance gene (ARG) removal from livestock mortality. Treatment conditions at temperatures between 150 and 200 degrees centigrade, at autogenic pressure, and times as short as 30 minutes resulted in complete pathogen kill and total removal of ARGs. -Development of an agriculturally focused new collection of Escherichia coli. ARS researchers assembled a publicly available collection (AgEc) that covers the four major animal production commodities – beef, dairy, poultry, and swine. This collection was the result of a collaborative effort that included researchers from ARS Florence and eight other ARS research units and covering 12 states. -Experimental data on constructed instream wetlands (ISWs) was used to model the large-scale impact of their implementation on water quality. The Soil and Water Assessment Tool (SWAT) was used to model nitrate export in a highly agricultural watershed located in the Coastal Plain of North Carolina. The results indicated that a watershed-wide implementation of ISWs is likely to reduce annual nitrate export by 49%. Implementation of ISWs on selected sub-basins can mitigate nitrate-N from non-point sources and enhance water quality in the watershed’s stream network. 3) Develop beneficial uses of agricultural, industrial, and municipal byproducts, including manure. -Engineered biochars were created to target specific soil deficiencies and their ability to improve corn (Zea mays L.) grain yields, soil fertility contents, soil microbial characteristics and enzymatic-mediated nutrient turnover processes. Although these engineered biochars enhanced nutrient uptake by corn stover, no grain yield or biomass improvement occurred. - Application of biochar to soil has emerged as an effective management strategy for sequestering carbon (C) in soils, reducing greenhouse gas emissions, and improving soil quality. A four-year field study was conducted to evaluate the changes in the C sequestration and C losses in highly weathered soils with one-time application of biochars under corn production. The average concentration of SOC and sequestered C increased by about 50% in highly weathered soils treated with biochar application when compared with the untreated control. - Municipal and agricultural waste byproducts were pyrolyzed to produce designer biochars possessing specific chemical characteristics targeting phytotoxic conditions at two USEPA superfund sites. Engineered biochars improved soil plant relationships by reducing heavy metal concentrations, raising soil pH and organic matter levels for improved plant phyto-stabilization.

Accomplishments
1. Biochar amendment improves soil health and revegetation in mining-impacted soils. The ongoing cleanup and remediation of the Oronogo-Duenweg Mining Belt area in Missouri, with most of the land privately owned, consists of removing and disposing of all heavy metal-contaminated soil materials. The cleanup process removed the soil's top layers, leaving a barren landscape with the soil's parent material exposed and no vegetation cover. Such undesirable terrain dissuaded landowners against costly but necessary remediation efforts to reduce the environmental impact of lead, zinc, and cadmium contamination. Therefore, the United States Environmental Protection Agency (USEPA) established an inter-agency agreement with ARS researchers in Florence, South Carolina, to investigate the use of biochar and compost as soil amendments to improve landscape restoration and management of revegetation of the mine-impacted soils. ARS researchers at Florence, South Carolina, developed and utilized an engineered blend of manure-based biochar and compost effective for binding residual heavy metals. The management practice of applying this engineered soil amendment improved the heavy metal-contaminated soils' physical, chemical, and biological properties, increasing soil health and fertility. This research showed that using the engineered biochar-compost blend to treat mine-impacted soils allowed the growth of prairie grasses in vegetation covers. This management practice provides USEPA with an additional tool to assist private landholders in restoring and revegetating mining-impacted land.

2. Enhancement of biogas production with ammonia recovery. Among the alternatives for improving manure management, anaerobic digestion and biogas production is considered a solution. However, the high ammonia concentration in manure reduces the potential production of biogas due to ammonia inhibition of the microorganisms (methanogens). ARS researchers in Florence, South Carolina, applied a new technology that separates ammonia from wastes with gas-permeable membranes to evaluate if the ammonia capture could improve biogas production from swine manure. Results showed that, by coupling the ammonia recovery technology with anaerobic digestion, the methane yield increased up to 28 % compared to a control treatment without ammonia recovery. In addition, the percentages of methane in biogas were higher. Therefore, the new treatment configuration enhances the quantity and quality of the biogas produced from manure and recovers ammonia nitrogen in a marketable ammonium salt.

3. Use of plastic mulch waste and animal manure to detoxify contaminated soils. Due to the lack of reuse of plastic mulch film (PMF) in agricultural production, recycling technologies are needed to avoid the wasteful, expensive, and environmentally unsustainable accumulation of plastic debris in landfills and natural ecosystems. ARS researchers in Florence, South Carolina, converted blends of PMF waste and animal manure into energy and a solid byproduct called “plastichar” via the thermal process of pyrolysis. The potential use of plastichar to treat pesticide-contaminated soil included plastichar’s enzymatic activation by soil incubation with earthworms (Lumbricus terrestris). The earthworms acted as biological vectors to facilitate the retention of enzymes onto the plastichar surface. Results revealed that plastichar-treated soils increased soil enzyme activity compared to plastichar-free soils, with the highest enzyme activity in the presence of earthworms. Because plastichar did not have lethal effects on earthworms, this finding strongly suggests the potential use of plastichar in tandem with earthworms to detoxify pesticide-contaminated soils.

U.S. DEPARTMENT OF AGRICULTURE

Coastal Plain Soil, Water and Plant Conservation Research: Florence, SC