ENHANCEMENT OF NITROGEN USAGE EFFICIENCY AND MITIGATION OF NITROUS OXIDE EMISSION IN AGRICULTURAL FIELDS

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: AFRI COMPETITIVE GRANT
• Reporting Frequency: Annual
• Accession No.: 1009711
• Grant No.: 2016-67020-25275
• Cumulative Award Amt.: $493,500.00
• Proposal No.: 2015-08576
• Project Start Date: Jun 15, 2016
• Project End Date: May 15, 2020
• Grant Year: 2016
• Program Code: [A1401]- Foundational Program: Soil Health

Recipient Organization
FLORIDA A&M UNIVERSITY
(N/A)
TALLAHASSEE,FL 32307

Performing Department
Civil and Environmental Engr

Non Technical Summary
Expanded global population and the consequent need for more food production have inevitably led to both an increase in the usage of synthetic fertilizers and a wider application of animal waste in agricultural soils. Most importantly, the applications of such nitrogen-based fertilizers and animal waste in many areas are excessive, with large proportions of the added nitrogen providing no benefit to crop yield, but elevated nitrogen loss (i.e., leaching or N2 conversion) and environmental impact (i.e., N2O emission). This research will evaluate various approaches (i.e., biochar, hydrogel, nitrification inhibitor and slow-release fertilizer applications) in increasing the efficiency of nitrogen assimilation as measured by nutrient usage efficiency criteria in the production value chain and by improvement in impaired natural resources. A combination of laboratory and field approaches will be adopted in this research and prediction tools that can accurately estimate nitrogen assimilation and loss from agricultural soils as well as environmental impact under different nitrogen conservation conditions will be developed. This project is designed to (1) improve the nitrogen utilization efficiency of nitrogen fertilizers and animal waste in agricultural fields, while minimizing nitrogen loss and environmental impact and (2) increase the understanding of nitrogen cycling in agricultural processes.

Animal Health Component

20%

Research Effort Categories

Basic

80%

Applied

20%

Developmental

0%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
102	0110	1000	100%

Knowledge Area
102 - Soil, Plant, Water, Nutrient Relationships;

Subject Of Investigation
0110 - Soil;

Field Of Science
1000 - Biochemistry and biophysics;

Keywords

agricultural fields

efficiency

mitigation

nitrogen usage

nitrous oxide

Goals / Objectives
The goal of this project is to potentially provide long-range improvement in maintaining the sustainability of U.S. agriculture and food systems. Our objective of this project is to evaluate various approaches (i.e., biochar, hydrogel, nitrification inhibitor and slow-release fertilizer applications) in increasing the efficiency of nitrogen assimilation as measured by nutrient usage efficiency criteria in the production value chain and by improvement in impaired natural resources. We will develop prediction tools to accurately estimate nitrogen assimilation and loss from agricultural soils as well as environmental impact under different nitrogen conservation conditions. This project is designed to (1) improve the nitrogen utilization efficiency of nitrogen fertilizers and animal waste in agricultural fields, while minimizing nitrogen loss and environmental impact and (2) increase the understanding of nitrogen cycling in agricultural processes.

Project Methods
We intend to use three levels of experimentation and modeling methods to conduct the proposed research, ranging from laboratory mechanistic investigation to field-scale implementation. These methods are designed to accomplish the three major tasks individually, and thus accomplish our research goals. The laboratory approach will focus on mechanistic investigation and quantification of nitrogen fate and transport as well as mechanisms of N2O generation and emission in agricultural soils under different nitrogen conservation conditions using 15N isotopes. The field approach will evaluate the increased efficiency of nitrogen assimilation as measured by nutrient usage efficiency criteria in the production value chain and reduced environmental impact in terms of N2O emission in the agricultural field. Based on the laboratory and field experimental results, nitrogen loss, nitrogen transformation and N2O generation and emission modules will be developed and incorporated into the Denitrification-Decomposition (DNDC) model.

Progress 06/15/19 to 06/14/20

Outputs
Target Audience:(1) Students at Florida A&M University Research discoveries have been incorporated into classroom teaching. Research opportunities have been provided to undergraduate students to participate in the laboratory and field research, and present their discoveries at symposiums and workshops. (2) METER Group, Inc. We gave a seminar to share our research and discoveries with Meter Group, Inc. in August 2019. We discussed with professionals of Meter Group, Inc. for possible on site nutrient monitoring in the agricultural field. (5) Students at California State Polytechnic University Pomona Research discoveries have been incorporated into classroom teaching atCalifornia State Polytechnic University Pomona, a Hispanic serving institution. Undergraduate students are encouraged to participate in the laboratory and field research. (6) Leon County High Schools We have collaborated with the AEESP Foundation Grant project and presented our research discoveries to high school students in Leon High of Tallahassee. (7) Minority Student Training One minority and one female student from Florida A&M University were sent to Washington State University to receive training. Research discoveries are exposed to students of African American and Hispanic serving institutions. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Dr. Chen has been involved in the oragnization of the Food Nexus International Summit held at Florida A&M University from Nov 7 to Nov 8, 2019. The students involved in this project as well as students that have been exposed to by this project have participated in the summit. At the summit, Dr. Chen has initiated the collaboration with scientists from China, based on which a proposal has been submitted to NSF in response to Dear Colleague Letter: NSF/NSFC Joint Research on Environmental Sustainability Challenges. How have the results been disseminated to communities of interest?At the International Summit held at Florida A&M University from Nov 7 to Nov 8, 2019, the research of this project was presented to the audience of scientist and researchers from all over the worlds including World Ocean Council, Finland, China, Hungary, and Rwanda, etc. This research has also been disseminated to the local communities through college open house. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Use of hydrogel and slow-release fertilizers on nutrient retention and reduction of nitrous oxide emission has been investigated. Specifically, experiments have been conducted to monitor the swelling performance of hydrogel and nutrient release of polyacrylamide (PAM)-coated biochar-fertilizer composition. Rapid swelling and slow nutrient release were observed, which were fitted with the Korsmeyer-Peppas model and Gallagher-Corrigan model. Mechanical and chemical properties were found to play important roles for hydrogel and PAM-coated biochar-fertilizer composition agricultural applications. During this reporting time, improvement on biochar performance by using microwave-mediated pyrolysis has also been studied. The physiochemical properties and nutrients/water retention capacities of biochar produced by the conventional method and microwave-mediated method were compared. The microwave-mediated method reduced the long heating duration and the secondary reaction of biochar pyrolysis. Lastly, life cycle assessments (LCAs) of the different soil amendments have been conducted and optimum application conditions are recommended based on comprehensive evaluation of economic benefits and environmental impacts. The outcomes of this research provides guidelines of agricultural sustainability by improving the efficiency of nutrient use in the agricultural field.

Publications

• Type: Journal Articles Status: Published Year Published: 2020 Citation: Li, S. and Chen, G., 2020, Effectiveness of dicyandiamide as a nitrification inhibitor in biochar- amended soil, Pedosphere, 30, 352-362.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Li, S. and Chen, G., 2020, Agricultural waste-derived superabsorbent hydrogels: Preparation, performance and socioeconomic impacts, Journal of Cleaner Production, 251, 119669. doi: 10.1016/j.jclepro.2019.119669.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Li, R., Zhang, Z., Li, S., Tang, Y., Wei, C. and Chen, G., 2019, Cadmium-bacteria complexation and subsequent bacteria-facilitated cadmium transport in saturated porous media, Journal of Environmental Quality, 48, 1524-1533.
• Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Wu, Y., Li, S. and Chen, G., Impact of humic acids on phosphorus retention and transport, Soil Science.
• Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Brickler, C., Wu, Y., Li, S., Anandhi, A. and Chen, G., Environmental impacts and cost analysis of nitrification inhibitors (DCD, DMPP, and nitrapyrin): A meta-analysis study, Science of the Total Environment.
• Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Wu, Y., Li, S. and Chen, G., Applications of hydrogels as water and nutrient reservoirs in agricultural soils, Environment, Development and Sustainability.
• Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Wu, Y., Li, S. and Chen, G., Impacts of mechanical and chemical factors on water-holding capacity of polyacrylamide in sandy soils: Models and mechanisms, Water and Environment Journal.
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2020 Citation: Li, S., Cost-effectiveness of using microwave-treated dewatered biosolids for land application, WEF/IWA Residuals and Biosolids 2020, Minneapolis, MN, April 2020. (Meeting canceled amid coronavirus outbreak)
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2020 Citation: Wu, Y., Brickler, C., Li, S. and Chen, G., Low-cost synthesis of cellulose-biochar composites for enhanced water and nitrogen use efficiency in agricultural fields, The 258th ACS National Meeting & Expo, Philadelphia, CA, March 2020. (Meeting canceled amid coronavirus outbreak)

Progress 06/15/16 to 06/14/20

Outputs
Target Audience:(1) Minority college students: Research discoveries have been incoporated into classroom teaching and research opportunities have been provided to undergraduate students to participate in the laboratory and field research and present their discoveries at symposiums and workshops at Florida A&M University (HBCU) and California State Polytechnic University Pomona (Hispanic serving institution). One minority student and one female student from Florida A&M University have received training at Washington State University. (2) High school students: Research discoveries have been presented to high school students in Leon County High School to stimulate high school students' interest in the topic area. (3) Goverment agencies: Research disvoveries have been presented at Florida Department of Environmental Protection and St. Johns River Water Management District. (4) Research institutions: Research discoveries have been presented at Florida Institute of Technology and California State Polytechnic University Pomona. (5) Industries: We have worked with the Meter Group, Inc. to seek solutions of field applications. (6) The general public: Research of this project has been exposed to the general public through the college open house. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?(1) Two Ph.D. students and one undergraduate student were trained in this project. The students were trained in experimental design and operation as well as data collection and analysis. The undergraduate student worked closely with the Ph.D. students during experimental operation and data collection. The undergraduate student was also trained to run laboratory analytical instruments. Ten papers have been published in technical journals from this research with the Ph.D. students as the first authors. Four more papers are under review. The undergraduate student was involved in the paper published in Journal of Cleaner Production (impact factor 6.395). (2) The Ph.D. students and undergraduate student presented the results of this project in seminars, workshops and national and international meetings. Dr. Chen was involved in the organization of the Food Nexus International Summit held at Florida A&M University from Nov 7 to Nov 8, 2019. The students of this project as well as students that have been exposed to by this project participated in the summit. At the summit, Dr. Chen initiated the collaboration with scientists from China, based on which a proposal has been submitted to NSF in response to Dear Colleague Letter: NSF/NSFC Joint Research on Environmental Sustainability Challenges. (3) The two Ph.D. students working on this project have graduated with four years' support of this project. One Ph.D. student has taken an assistant professor position at California State Polytechnic University Pomona and the other Ph.D. student has taken a postdoctoral research associate position at Florida A&M University. How have the results been disseminated to communities of interest?(1) The research of this project has been disseminated by the following news media: http://www.famunews.com/2016/08/impactful-research-a-signature-component-of-proposed-strategic-plan/ https://theconversation.com/microwaving-sewage-waste-may-make-it-safe-to-use-as-fertilizer-on-crops-128776 https://phys.org/news/2019-12-microwave-treatment-inexpensive-heavy-metals.html https://thecounter.org/biosolids-sewage-sludge-fertilizer-heavy-metals-microwave/ https://www.eng.famu.fsu.edu/news/microwaving-sewage-waste-may-make-it-safe-to-use-as-fertilizer-on-crops https://news.fsu.edu/news/science-technology/2019/12/05/fsu-research-microwave-treatment-is-an-inexpensive-way-to-clean-heavy-metals-from-treated-sewage/ https://news.fsu.edu/news/2020/04/07/fsu-research-repurposing-straw-lets-farmers-grow-more-food-with-less-water-and-fertilizer/ https://www.eng.famu.fsu.edu/news/hydrogel-from-straw (2) A website has been created at Florida A&M University to disseminate the project information, progress, and major findings. (3) This project has been disseminated to the general public during the college open house. The general public including many k-12 students are exposed to this project and learned the fundamental theory of nitrogen cycling. (4) This project has been disseminated to govenment agencies including Florida Department of Protection Agency and St John River Water District. (5) At the International Summit held at Florida A&M University from Nov 7 to Nov 8, 2019, the research of this project was presented to the audience of scientist and researchers from all over the world including World Ocean Council, Finland, China, Hungary, and Rwanda, etc. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? (1) Biochar was produced from switchgrass, water oak and biosolids (dewatered wastewater sludge) under variable pyrolysis temperature. The produced biochar was fully characterized. Nutrient sorption to the produced biochar was investigated. The results provided the evidence of micro-scale structural differences of biochar produced at different pyrolysis temperature, which led to different nutrient sorption. This phenomenon was significantly pronounced at 600oC and higher as a consequence of complete carbon thermal degradation and strengthened aromatization. The performance of soil amendment with biochar was found to be a function of many factors, among which pyrolysis temperature and feedstock type were believed to be the most decisive because they were directly related to the physicochemical properties of biochar. An average 54% reduction of N2O emission in biochar-amended soil was observed when the biochar was applied to the agricultural field. Improvement on biochar production by using microwave-mediated biochar pyrolysis was also studied. The physiochemical properties and nutrient/water retention capacities of biochar produced by the conventional method and microwave-mediated method were compared. The microwave-mediated method reduced the long heating duration and the secondary reaction of biochar pyrolysis. (2) The ability of dicyandiamide (DCD) in inhibiting nitrification and subsequent N2O emission at different incubation temperature were explored. Although DCD was found to have a positive effect on N2O emission mitigation, DCD was readily to be decomposed in the agricultural soil. DCD degradation was found to be significantly influenced by the temperature. The half-life of DCD was around 50 days at 16oC, which dropped to 10 days at 30oC. At 25oC, most of the DCD was decomposed within 25 days. (3) Use of hydrogel and slow-release fertilizers on nutrient retention and reduction of nitrous oxide emission was investigated. Specifically, experiments were conducted to monitor the swelling performance of hydrogel and nutrient release of polyacrylamide (PAM)-coated biochar-fertilizer composition. Rapid swelling and slow nutrient release were observed, which were fitted with the Korsmeyer-Peppas model and Gallagher-Corrigan model. Mechanical and chemical properties were found to play important roles for hydrogel and PAM-coated biochar-fertilizer composition agricultural applications. (4) Life cycle assessments (LCAs) of the different soil amendment were conducted and optimum application conditions are recommended based on the comprehensive evaluation of economic benefits and environmental impacts. The outcomes of this research provides guidelines of agricultural sustainability by improving the efficiency of nutrient use and reduction of N2O emission in the agricultural soil.

Publications

• Type: Journal Articles Status: Published Year Published: 2020 Citation: Li, S. and Chen, G., 2020, Effectiveness of dicyandiamide as a nitrification inhibitor in biochar- amended soil, Pedosphere, 30, 352-362.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Li, S. and Chen, G., 2020, Agricultural waste-derived superabsorbent hydrogels: Preparation, performance and socioeconomic impacts, Journal of Cleaner Production, 251, 119669. doi: 10.1016/j.jclepro.2019.119669.
• Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Wu, Y., Li, S. and Chen, G., Impact of humic acids on phosphorus retention and transport, Soil Science.
• Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Brickler, C., Wu, Y., Li, S., Anandhi, A. and Chen, G., Environmental impacts and cost analysis of nitrification inhibitors (DCD, DMPP, and nitrapyrin): A meta-analysis study, Science of the Total Environment.
• Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Wu, Y., Li, S. and Chen, G., Applications of hydrogels as water and nutrient reservoirs in agricultural soils, Environment, Development and Sustainability.
• Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Wu, Y., Li, S. and Chen, G., Impacts of mechanical and chemical factors on water-holding capacity of polyacrylamide in sandy soils: Models and mechanisms, Water and Environment Journal.
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2020 Citation: Li, S., Cost-effectiveness of using microwave-treated dewatered biosolids for land application, WEF/IWA Residuals and Biosolids 2020, Minneapolis, MN, April 2020. (Meeting canceled amid Coronavirus outbreak)
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2020 Citation: Wu, Y., Brickler, C., Li, S. and Chen, G., Low-cost synthesis of cellulose-biochar composites for enhanced water and nitrogen use efficiency in agricultural fields, The 258th ACS National Meeting & Expo, Philadelphia, CA, March 2020. (Meeting canceled amid Coronavirus outbreak)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Li, R., Zhang, Z., Li, S., Tang, Y., Wei, C. and Chen, G., 2019, Cadmium-bacteria complexation and subsequent bacteria facilitated cadmium transport in saturated porous media, Journal of Environmental Quality, 48, 1524-1533.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Li, S., Harris, S., Anandhi, A. and Chen, G., 2019, Predicting biochar properties and functions based on feedstock and pyrolysis temperature: A review and data syntheses, Journal of Cleaner Production, 215, 890-902.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Li, S. and Chen, G., 2019, Contemporary strategies for enhancing nitrogen retention and mitigating nitrous oxide emission in agricultural soils: Present and future, Environment, Development and Sustainability, 22, 2703-2741.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Li, S., Chen, G. and Anandhi, A., 2018, Applications of Emerging Bioelectrochemical Technologies in Agricultural Systems: A Current Review, Energies, 11, 2951. doi:10.3390/en11112951.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Li, S. and Chen, G., 2018, Using hydrogel-biochar composites for enhanced cadmium removal from aqueous media, Material Science & Engineering International Journal, 2, 294-298.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Li, S. and Chen, G., 2018, Factors affecting the effectiveness of bioelectrochemical system applications: Data synthesis and meta-analysis, Batteries, 4, 34. doi: 10.3390/batteries4030034.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Li, S., Barreto, V., Li, R., Chen, G. and Hsieh, Y.P., 2018, Nitrogen retention of biochar derived from different feedstocks at variable temperatures, Journal of Analytical and Applied Pyrolysis, 133, 136-146.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Li, S. and Chen, G., 2018, Thermogravimetric, thermochemical, and infrared spectral characterization of feedstocks and biochar derived at different pyrolysis temperatures, Waste Management, 78, 198-207.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Li, S. and Chen, G., 2019, Biochar production from biosolids, WEF/IWA Residuals and Biosolids Conference, May 7  May 10, Fort Lauderdale, Florida, USA.
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Li, S., Li, R. and Chen, G., Fate and transport of dicyandiamide (DCD) and its nitrification inhibition in agricultural soils, 255rd ACS National Meeting, New Orleans, LA, March 18-22, 2018.
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Li, S., Barreto, V., Li, R., Chen, G. and Hsieh, Y., Nitrogen sorption by biochars derived from different feedstocks and at different pyrolysis temperatures: Affecting factors and mechanisms, 255rd ACS National Meeting, New Orleans, LA, March 18-22, 2018.
• Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Li, S. and Chen, G., Mechanistic investigation of nitrification inhibition and subsequent nitrous oxide (N2O) emission, 253rd ACS National Meeting, Division of Agricultural and Food Chemistry, San Francisco, California, April 2-6, 2017.

Progress 06/15/16 to 05/15/20

Outputs
Target Audience:(1) Minority college students: Research discoveries have been incoporated into classroom teaching and research opportunities have been provided to undergraduate students to participate in the laboratory and field research and present their discoveries at symposiums and workshops at Florida A&M University (HBCU) and California State Polytechnic University Pomona (Hispanic serving institution). One minority student and one female student from Florida A&M University have received training at Washington State University. (2) High school students: Research discoveries have been presented to high school students in Leon County High School to stimulate high school students' interest in the topic area. (3) Goverment agencies: Research disvoveries have been presented at Florida Department of Environmental Protection and St. Johns River Water Management District. (4) Research institutions: Research discoveries have been presented at Florida Institute of Technology and California State Polytechnic University Pomona. (5) Industries: We have worked with the Meter Group, Inc. to seek solutions of field applications. (6) The general public: Research of this project has been exposed to the general public through the college open house. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?(1) Two Ph.D. students and one undergraduate student were trained in this project. The students were trained in experimental design and operation as well as data collection and analysis. The undergraduate student worked closely with the Ph.D. students during experimental operation and data collection. The undergraduate student was also trained to run laboratory analytical instruments. Ten papers have been published in technical journals from this research with the Ph.D. students as the first authors. Four more papers are under review. The undergraduate student was involved in the paper published in Journal of Cleaner Production (impact factor 6.395). (2) The Ph.D. students and undergraduate student presented the results of this project in seminars, workshops and national and international meetings. Dr. Chen was involved in the organization of the Food Nexus International Summit held at Florida A&M University from Nov 7 to Nov 8, 2019. The students of this project as well as students that have been exposed to by this project participated in the summit. At the summit, Dr. Chen initiated the collaboration with scientists from China, based on which a proposal has been submitted to NSF in response to Dear Colleague Letter: NSF/NSFC Joint Research on Environmental Sustainability Challenges. (3) The two Ph.D. students working on this project have graduated with four years' support of this project. One Ph.D. student has taken an assistant professor position at California State Polytechnic University Pomona and the other Ph.D. student has taken a postdoctoral research associate position at Florida A&M University. How have the results been disseminated to communities of interest?(1) The research of this project has been disseminated by the following news media: http://www.famunews.com/2016/08/impactful-research-a-signature-component-of-proposed-strategic-plan/ https://theconversation.com/microwaving-sewage-waste-may-make-it-safe-to-use-as-fertilizer-on-crops-128776 https://phys.org/news/2019-12-microwave-treatment-inexpensive-heavy-metals.html https://thecounter.org/biosolids-sewage-sludge-fertilizer-heavy-metals-microwave/ https://www.eng.famu.fsu.edu/news/microwaving-sewage-waste-may-make-it-safe-to-use-as-fertilizer-on-crops https://news.fsu.edu/news/science-technology/2019/12/05/fsu-research-microwave-treatment-is-an-inexpensive-way-to-clean-heavy-metals-from-treated-sewage/ https://news.fsu.edu/news/2020/04/07/fsu-research-repurposing-straw-lets-farmers-grow-more-food-with-less-water-and-fertilizer/ https://www.eng.famu.fsu.edu/news/hydrogel-from-straw (2) A website has been created at Florida A&M University to disseminate the project information, progress, and major findings. (3) This project has been disseminated to the general public during the college open house. The general public including many k-12 students are exposed to this project and learned the fundamental theory of nitrogen cycling. (4) This project has been disseminated to govenment agencies including Florida Department of Protection Agency and St John River Water District. (5) At the International Summit held at Florida A&M University from Nov 7 to Nov 8, 2019, the research of this project was presented to the audience of scientist and researchers from all over the world including World Ocean Council, Finland, China, Hungary, and Rwanda, etc. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? (1) Biochar was produced from switchgrass, water oak and biosolids (dewatered wastewater sludge) under variable pyrolysis temperature. The produced biochar was fully characterized. Nutrient sorption to the produced biochar was investigated. The results provided the evidence of micro-scale structural differences of biochar produced at different pyrolysis temperature, which led to different nutrient sorption. This phenomenon was significantly pronounced at 600oC and higher as a consequence of complete carbon thermal degradation and strengthened aromatization. The performance of soil amendment with biochar was found to be a function of many factors, among which pyrolysis temperature and feedstock type were believed to be the most decisive because they were directly related to the physicochemical properties of biochar. An average 54% reduction of N2O emission in biochar-amended soil was observed when the biochar was applied to the agricultural field. Improvement on biochar production by using microwave-mediated biochar pyrolysis was also studied. The physiochemical properties and nutrient/water retention capacities of biochar produced by the conventional method and microwave-mediated method were compared. The microwave-mediated method reduced the long heating duration and the secondary reaction of biochar pyrolysis. (2) The ability of dicyandiamide (DCD) in inhibiting nitrification and subsequent N2O emission at different incubation temperature were explored. Although DCD was found to have a positive effect on N2O emission mitigation, DCD was readily to be decomposed in the agricultural soil. DCD degradation was found to be significantly influenced by the temperature. The half-life of DCD was around 50 days at 16oC, which dropped to 10 days at 30oC. At 25oC, most of the DCD was decomposed within 25 days. (3) Use of hydrogel and slow-release fertilizers on nutrient retention and reduction of nitrous oxide emission was investigated. Specifically, experiments were conducted to monitor the swelling performance of hydrogel and nutrient release of polyacrylamide (PAM)-coated biochar-fertilizer composition. Rapid swelling and slow nutrient release were observed, which were fitted with the Korsmeyer-Peppas model and Gallagher-Corrigan model. Mechanical and chemical properties were found to play important roles for hydrogel and PAM-coated biochar-fertilizer composition agricultural applications. (4) Life cycle assessments (LCAs) of the different soil amendment were conducted and optimum application conditions are recommended based on the comprehensive evaluation of economic benefits and environmental impacts. The outcomes of this research provides guidelines of agricultural sustainability by improving the efficiency of nutrient use and reduction of N2O emission in the agricultural soil.

Publications

• Type: Journal Articles Status: Published Year Published: 2020 Citation: Li, S. and Chen, G., 2020, Effectiveness of dicyandiamide as a nitrification inhibitor in biochar- amended soil, Pedosphere, 30, 352-362.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Li, S. and Chen, G., 2020, Agricultural waste-derived superabsorbent hydrogels: Preparation, performance and socioeconomic impacts, Journal of Cleaner Production, 251, 119669. doi: 10.1016/j.jclepro.2019.119669.
• Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Wu, Y., Li, S. and Chen, G., Impact of humic acids on phosphorus retention and transport, Soil Science.
• Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Brickler, C., Wu, Y., Li, S., Anandhi, A. and Chen, G., Environmental impacts and cost analysis of nitrification inhibitors (DCD, DMPP, and nitrapyrin): A meta-analysis study, Science of the Total Environment.
• Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Wu, Y., Li, S. and Chen, G., Applications of hydrogels as water and nutrient reservoirs in agricultural soils, Environment, Development and Sustainability.
• Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Wu, Y., Li, S. and Chen, G., Impacts of mechanical and chemical factors on water-holding capacity of polyacrylamide in sandy soils: Models and mechanisms, Water and Environment Journal.
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2020 Citation: Li, S., Cost-effectiveness of using microwave-treated dewatered biosolids for land application, WEF/IWA Residuals and Biosolids 2020, Minneapolis, MN, April 2020. (Meeting canceled amid Coronavirus outbreak)
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2020 Citation: Wu, Y., Brickler, C., Li, S. and Chen, G., Low-cost synthesis of cellulose-biochar composites for enhanced water and nitrogen use efficiency in agricultural fields, The 258th ACS National Meeting & Expo, Philadelphia, CA, March 2020. (Meeting canceled amid Coronavirus outbreak)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Li, R., Zhang, Z., Li, S., Tang, Y., Wei, C. and Chen, G., 2019, Cadmium-bacteria complexation and subsequent bacteria facilitated cadmium transport in saturated porous media, Journal of Environmental Quality, 48, 1524-1533.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Li, S., Harris, S., Anandhi, A. and Chen, G., 2019, Predicting biochar properties and functions based on feedstock and pyrolysis temperature: A review and data syntheses, Journal of Cleaner Production, 215, 890-902.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Li, S. and Chen, G., 2019, Contemporary strategies for enhancing nitrogen retention and mitigating nitrous oxide emission in agricultural soils: Present and future, Environment, Development and Sustainability, 22, 2703-2741.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Li, S., Chen, G. and Anandhi, A., 2018, Applications of Emerging Bioelectrochemical Technologies in Agricultural Systems: A Current Review, Energies, 11, 2951. doi:10.3390/en11112951.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Li, S. and Chen, G., 2018, Using hydrogel-biochar composites for enhanced cadmium removal from aqueous media, Material Science & Engineering International Journal, 2, 294-298.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Li, S. and Chen, G., 2018, Factors affecting the effectiveness of bioelectrochemical system applications: Data synthesis and meta-analysis, Batteries, 4, 34. doi: 10.3390/batteries4030034.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Li, S., Barreto, V., Li, R., Chen, G. and Hsieh, Y.P., 2018, Nitrogen retention of biochar derived from different feedstocks at variable temperatures, Journal of Analytical and Applied Pyrolysis, 133, 136-146.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Li, S. and Chen, G., 2018, Thermogravimetric, thermochemical, and infrared spectral characterization of feedstocks and biochar derived at different pyrolysis temperatures, Waste Management, 78, 198-207.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Li, S. and Chen, G., 2019, Biochar production from biosolids, WEF/IWA Residuals and Biosolids Conference, May 7  May 10, Fort Lauderdale, Florida, USA.
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Li, S., Li, R. and Chen, G., Fate and transport of dicyandiamide (DCD) and its nitrification inhibition in agricultural soils, 255rd ACS National Meeting, New Orleans, LA, March 18-22, 2018.
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Li, S., Barreto, V., Li, R., Chen, G. and Hsieh, Y., Nitrogen sorption by biochars derived from different feedstocks and at different pyrolysis temperatures: Affecting factors and mechanisms, 255rd ACS National Meeting, New Orleans, LA, March 18-22, 2018.
• Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Li, S. and Chen, G., Mechanistic investigation of nitrification inhibition and subsequent nitrous oxide (N2O) emission, 253rd ACS National Meeting, Division of Agricultural and Food Chemistry, San Francisco, California, April 2-6, 2017.

Progress 06/15/18 to 06/14/19

Outputs
Target Audience:(1) Students at FAMU-FSU College of Engineering We have incorporated our research discoveries into our class teaching and provided research opportunities for undergraduate students to participate in the laboratory and field research and present their discoveries at on-campus symposiumsand workshops. (2) Florida Department of Environmental Protection We gave a seminar to share our research and discoveries atFlorida Department of Environmental Protection in April 2019. (3) St. Johns River Water Management District We gave a seminar to share our research and discoveries at St. Johns River Water Management District in April 2019. (4) Florida Institute of Technology We gave a seminar to share our research and discoveries at Florida Institute of Technology in April 2019. (5) California State Polytechnic University Pomona We gave a seminar to share our research and discoveries at Cal Poly Pomona in February 2019. (6) Leon County High Schools We have collaborated with the AEESP Foundation Grant project and presented our research discoveries to high school students in the metropolitan area of Tallahassee. (7) Industry We have worked with Meter Group to seek engineering field applications. (8) Minority Student Training One minority and one female student from Florida A&M University were sent to Washington State University to receive training. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Two Ph.D. students and one undergraduate are trained in this project. Specifically, the Ph.D. students are trained in experimental design and operation as well as data collection, analysis and manuscript writing. The undergraduate student works closely with the Ph.D. students during experimental operation and data collection. The undergraduate student is also trained to run laboratory analytical instruments and in technical writing. The undergraduate student is the co-author of one of the journal publications during this reporting period. How have the results been disseminated to communities of interest?This project is disseminated to the general public by presentations at Florida Department of Protection Agency, St John River Water District, Florida Institute of Technology, California State Polytechnic University Pomona, college open house, and high school classroom demonstration. Above general public are exposed to this project and learn the fundamental theory of nitrogen cycling. A website has been created at Florida A&M University to disseminate project information, progress, and major findings. Important project outcomes have been disseminated through college and university newsletters and other news media. What do you plan to do during the next reporting period to accomplish the goals?For the next reporting period, use of hydrogel and slow-release fertilizer on nutrient retention and reduction of nitrous oxide emission will be reported.

Impacts
What was accomplished under these goals? This project examines the increase of nitrogen usage efficiency and reduced environmental impact of fertilizer and animal waste practices under biochar, hydrogel, nitrification inhibitor and slow-release fertilizer application conditions across soil-air-water interfaces. The expected outcome of this proposed research is to provide guidelines to improve agricultural sustainability and efficiency of the usage of nitrogen-based fertilizers and animal waste in agricultural fields by developing predictive tools to evaluate nitrogen assimilation and N2O emission. This research focuses on the fundamental understanding of the processes. During this research period, we continued to investigate the use of biochar and dicyandiamide (DCD) on mitigating N2O emission. We found that an average 54% reduction of N2O emission in biochar-amended soils can be achieved. The performance of biochar amendment is a function of many factors, among which the production method, pyrolysis temperature and feedstock type are believed to be the most decisive because they are directly related to the physicochemical properties of biochar. Although DCD was found to have a positive effect on N2O emission mitigation, DCD was readily to be decomposed in the agricultural soil. At 25oC, most of the DCD can be decomposed within 25 days. DCD degradation was found to be significantly influenced by the temperature. The half-life of DCD was around 50 days at 16oC, which dropped to 10 days at 30oC. We have also conducted the testing of mechanical stress on hydrogel and water infiltration experiments of hydrogel as a function of ionic strength.

Publications

• Type: Journal Articles Status: Published Year Published: 2019 Citation: Li, S., Harris, S., Anandhi, A. and Chen, G., 2019, Predicting biochar properties and functions based on feedstock and pyrolysis temperature: A review and data syntheses, Journal of Cleaner Production, 215, 890-902.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Li, S. and Chen, G., 2019, Contemporary strategies for enhancing nitrogen retention and mitigating nitrous oxide emission in agricultural soils: Present and future, Environment, Development and Sustainability, https://doi.org/10.1007/s10668-019-00327-2.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Li, S., Chen, G., Anandhi, A., 2018, Applications of Emerging Bioelectrochemical Technologies in Agricultural Systems: A Current Review, Energies, 11, 2951; doi:10.3390/en11112951.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Li, S., Li, R., Barreto, V., Chen, G. and Hsieh, Y., 2018, Nitrogen retention of biochars derived from different feedstocks at variable pyrolysis temperatures, Journal of Analytical and Applied Pyrolysis, 133, 136-146.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Li, S. and Chen, G., 2018, Thermogravimetric, thermochemical, and infrared spectral characterization of feedstocks and biochar derived at different pyrolysis temperatures, Waste Management, 78, 198-207.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Li, S. and Chen, G., 2019, Biochar production from biosolids, WEF/IWA Residuals and Biosolids Conference, May 7  May 10, Fort Lauderdale, Florida, USA.

Progress 06/15/17 to 06/14/18

Outputs
Target Audience:We discuss and share the knowledge of this project with Florida Department of Environmental Protection, Florida Department of Agriculture & Consumer Services, and Center for Forest Watershed Research of USDA Forest Service. We present the research discovery at international and national meetings to exchange ideas with scientists and professionals. Graduate and undergraduate students, including African America students are trained in the laboratory. The general public also learns this project in our laboratory through the college open house. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Two Ph.D. students and one undergraduate are trained in this project. Specifically, the Ph.D. students are trained in experimental design and operation as well as data collection and analysis. The undergraduate student works closely with the Ph.D. students during experimental operation and data collection. The undergraduate student is also trained to run laboratory analytical instruments. The Ph.D. students also present the results of this project in seminars organized by the department and college. How have the results been disseminated to communities of interest?This project is disseminated to the general public during the college open house. The general public including many k-12 students are exposed to this project and learn the fundamental theory of nitrogen cycling. What do you plan to do during the next reporting period to accomplish the goals?For the next reporting period, increase of the efficiency of nitrogen retention by hydrogel and slow-release fertilizer will be evaluated, including the reduction of nitrous oxide emission.

Impacts
What was accomplished under these goals? This project examines the increase of nitrogen usage efficiency and reduced environmental impact of fertilizer and animal waste practices under biochar, hydrogel, nitrification inhibitor and slow-release fertilizer application conditions across soil-air-water interfaces. The expected outcome of this proposed research is to provide guidelines to improve agricultural sustainability and efficiency of the usage of nitrogen-based fertilizers and animal waste in agricultural fields by developing predictive tools to evaluate nitrogen assimilation and N2O emission. This research focuses on the fundamental understanding of the processes. During this research period, we characterized the physiochemical properties of three feedstocks (switchgrass, water oak and biosolid) using different techniques to understand the influence of the pyrolysis temperature and feedstock type on the biochar performance. This research provided the evidence of micro-scale structural differences of biochar produced at different pyrolysis temperatures, which led to different nitrogen sorption capacities. This phenomenon was significantly pronounced at 600oC and higher as a consequence of complete carbon thermal degradation and strengthened aromatization. We also studied the ability of dicyandiamide (DCD) in inhibiting nitrification and subsequent N2O emission at different incubation temperatures. The effectiveness of DCD was found to decrease with the increase of incubation temperature.

Publications

• Type: Journal Articles Status: Under Review Year Published: 2018 Citation: Li, S., Chen, G., Li, R., Barreto, V. and Hsieh, Y., Nitrogen retention of biochars derived from different feedstocks at variable pyrolysis temperatures, Journal of Analytical and Applied Pyrolysis, under revision.
• Type: Journal Articles Status: Under Review Year Published: 2018 Citation: Li, S. and Chen, G., Effectiveness of dicyandiamide as nitrification inhibitor in mitigating nitrous oxide emission during nitrification, Journal of Environmental Quality, under review.
• Type: Journal Articles Status: Under Review Year Published: 2018 Citation: Li, S. and Chen, G., Contemporary strategies for enhancing nitrogen retention and mitigating nitrous oxide emission in agricultural soils: Present and future, Science of the Total Environment, under review.
• Type: Journal Articles Status: Under Review Year Published: 2018 Citation: Li, S. and Chen, G., Thermogravimetric, thermochemical, and infrared spectral characterization of feedstocks and biochar derived at different pyrolysis temperatures, Waste Management, under review.
• Type: Conference Papers and Presentations Status: Awaiting Publication Year Published: 2018 Citation: Li, S., Li, R. and Chen, G., Fate and transport of dicyandiamide (DCD) and its nitrification inhibition in agricultural soils, 255rd ACS National Meeting, New Orleans, LA, March 18-22, 2018.
• Type: Conference Papers and Presentations Status: Awaiting Publication Year Published: 2018 Citation: Li, S., Barreto, V., Li, R., Chen, G. and Hsieh, Y., Nitrogen sorption by biochars derived from different feedstocks and at different pyrolysis temperatures: affecting factors and mechanisms, 255rd ACS National Meeting, New Orleans, LA, March 18-22, 2018.

Progress 06/15/16 to 06/14/17

Outputs
Target Audience:Florida Department of Environmental Protection, Florida Department of Agriculture & Consumer Services, Center for Forest Watershed Research of USDA Forest Service, college students, and the general public. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Two Ph.D. students have been trained in this project. How have the results been disseminated to communities of interest?The research of this project has been disseminated by FAMU new media: http://www.famunews.com/2016/08/impactful-research-a-signature-component-of-proposed-strategic-plan/ What do you plan to do during the next reporting period to accomplish the goals?Hydrogel and slow-release fertilizer applications, Nitrous oxide emission from nitrification and denitrification.

Impacts
What was accomplished under these goals? 1. Biochar has been produced from switchgrass under varibale temperatures and has been fully characterized. 2. Experiments of nutrient soprtion to the produced biochar is ongoing. 3. Nitrification inhibation experiments are underway.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Li, S. and Chen, G., Mechanistic investigation of nitrification inhibition and subsequent nitrous oxide (N2O) emission, 253rd ACS National Meeting, Division of Agricultural and Food Chemistry, San Francisco, California, April 2-6, 2017.