Seminars – Fall 2020

Crop and Soil Sciences Fall 2020 Seminar Series

Nov 11, 2020 03:40 PM Eastern Time (US and Canada)
Dr. Natalie Nelson
Asst. Prof., Dept. of Biological and Agricultural Engineering/ NCSU
Innovations in sensing and computation have created new opportunities for machine learning to advance natural resources management towards data-driven prediction and decision-making. Yet, the use of machine learning for predictive modeling in natural resources management remains limited, particularly outside of academia. This talk will review findings from a stakeholder workshop in which a group of applied researchers and practitioners who analyze data or model environmental and agricultural system dynamics were engaged to identify the factors they perceived as barriers to using machine learning. Ideas as to how to overcome these barriers will be offered, as will a case study that highlights how machine learning can enhance and complement models currently used in practice.

Wed Nov 4, 2020 3:40pm – 4:40pm

 “Harnessing (Bio-) Electrochemical Technologies as Sustainable Sources for On-Demand Precision Agriculture

Dr. Katharina Staplemann
Asst. Prof., Plasma for Life Sciences, Department of Nuclear Engineering/NCSU:

The seminar talk will give an overview of the recently awarded GRIP4PSI project. Our team is rethinking how water- and nitrogen-based fertilizers are used in order to enable the next generation of sustainable and cost-effective farms. We have developed two game-changing bioelectrochemical technologies, which harness chemical and electrical energy to produce a more sustainable nitrogen-based fertilizer. Using advanced novel sensor and delivery systems, we will be able to precisely supply fertilizers for sustainable precision agriculture. Special focus of the seminar talk will be the introduction of non-thermal plasma as one of the bioelectrochemical technologies, and the application of potential of non-thermal plasmas in agriculture.


Wed Oct 28, 2020

Chris Moritz
M.S. Student: Soil Science
Dept. of Crop and Soil Sciences/NCSU

“Evaluating Restoration Sites in Carolina Bay Wetlands”

Over $500 million have been spent restoring wetlands in North Carolina, yet no agreed-upon methods exist to determine restoration success. Carbon accretion is proposed as one property that can be measured to evaluate restoration success. The study objectives were to determine the amounts of C accreting in restored Carolina Bay wetlands (CBWs) in soil organic C (SOC), the litter layer, and aboveground biomass. The main study site was Juniper Bay in Robeson County, a CBW that had been restored for 15 years following its use for agriculture. Sampling plots were placed where previous studies determined pre-restoration SOC, and post-restoration hydrology. We collected samples to determine SOC to 75 cm, litter layer thickness, and soil morphological characteristics. Vegetation at each plot was characterized by determining vegetation type, and tree basal area and height. Saturation durations and SOC concentrations were geointerpolated throughout the bay. Indicator of Reduction in Soils (IRIS) tubes were installed at selected plots. Hydrology indicators were collected at each sample location. Sampling plots were grouped by saturation duration within 30 cm of the soil surface: 14, 14-50, 51-100, or 101+ consecutive days during the growing season. The IRIS tube measurements confirmed that saturation and anerobic conditions occurred in all plots. The number of hydrology indicators increased 70% going from 14 to 101+ days of saturation. Soil OC within 30 cm decreased 44-58% in all soil plots compared to pre-restoration levels. Where saturation occurred for 101+ days, litter thickness increased 33-55%, and tree basal area and height decreased 40-69% compared to where saturation occurred for shorter periods. Analyses from eight other restored CBWs showed that litter thickness, and tree basal area and height could be used to evaluate restoration success for different ages of restored wetlands. Because SOC decreased following restoration, it provided little potential for evaluating restoration success.

Wednesday October 21

Sydney Bufkin
M.S. Student
Dept of Crop & Soil Sciences / NCSU

Phosphorus-Optimal Wetlands: Operationalizing Systems for Maximum Nutrient Retention” 

The loss of P in runoff from agricultural fields has been linked to the increase of harmful algal blooms (HABs) and other water quality impairments in the Great Lakes region. Constructed and restored wetlands can be a solution to the P loading due to their natural capacity for P removal, however, P retention is finite, and some areas could be limited by soil legacy P resulting from past fertilization. In this study, the first project evaluated the P retention capacity of the surface and subsurface horizons of agricultural soils (Paulding clay) at a proposed wetland site within the Maumee River watershed in the Great Lakes region. Soil P isotherms were evaluated under cold (10˚C), warm (22˚C), aerobic, and anaerobic treatments. In general, higher temperatures and aerobic conditions increased P retention. Soil-amendment experiments using alum and Fe were also conducted to investigate their effectiveness for increasing P retention. The alum and Fe increased P sorption capacity up to 7 and 25%, respectively. At environmentally relevant added P concentrations (concentrations less than 10 mg/L), nearly 100% of P was retained by the soils without the addition of soil amendments. This suggests that the soils evaluated in this study are appropriate for construction of treatment wetland. A second project will scale up wetland processes in environmentally relevant conditions by creating mesocosms to study the effects of redox status, vegetation, and soil amendments on P retention over the lifecycle of wetland systems designed for nutrient retention. This information will be useful for improving the design, construction, and management of wetlands to maximize P retention and improve water quality.


Wednesday October 14

Dr. Arnab Bhowmik, Asst. Prof., Dept. of Natural Resources & Environmental Design, NC Agricultural and Technical State University, will present a seminar titled:

Biological Soil Health Management for Climate-Adaptive Agroecosystems

Climate-adaptive management practices have the potential to improve soil health and provide ecosystem services. However, if not properly managed these systems might contribute to increased greenhouse gas emissions thereby offsetting the benefits. Novel and potential biological soil health indicators were measured at field and lab scales in a wide range of agroecosystems in the United States. These included long-term experimental plots affiliated with North Dakota State University, Washington State University and the Pennsylvania State University. Our studies evaluate the effect of soil health management practices like reduced tillage, incorporation of animal wastes, cover cropping and crop rotations on soil microbial communities, their functions and greenhouse gas emissions. Results indicate that better understanding of the key microbial players involved in nitrogen cycling and their response to different soil conditions are crucial for soil health improvement and reduced greenhouse gas emission.


Thursday, October 1, 2020

Special Crop and Soil Sciences Post-Sabbatical Seminar

Dr. Dean Hesterberg, Prof., Dept. of Crop and Soil Sciences/NCSU,
will present via Zoom a seminar titled:
This seminar will give a retrospective of my synchrotron research work leading up to and including a 1-year study leave at the new Sirius synchrotron in Campinas, Brazil. This 4th-generation machine produces a unique combination of high-intensity and highly coherent X-rays. A number of complementary X-ray beamlines at Sirius show great promise for revealing novel insights into soils and other natural systems. My research work at Sirius mainly focused in two areas: (1) development of a “rhizomicrocosm” system for in-vivo 5-dimensional imaging of chemical elements in the soil-rhizosphere interface of plant roots, and (2) theoretical modeling of a system for high-resolution chemical species imaging in soils. In project 1, our team of physicists, biologists, engineers, a soil scientist, and a crop scientist developed a prototype system and collected computed tomography (CT) images of wheat roots growing into tapered capillaries filled with soil material sampled from a Brazilian Oxisol. Roots of ~450 µm diameter grew at overall rates of up to 700 µm/h through the tapered capillaries. Results provide insights to a planned work flow at Sirius that includes rapid CT imaging at the MOGNO beamline to image root habit, followed by submicron-scale 3D chemical imaging and X-ray absorption spectroscopy over time at the CARNAÚBA beamline to directly follow chemical movement from, for example, a fertilizer granule through soil to a living root. In project 2, we are assessing the potential gain in chemical species resolution by X-ray absorption spectroscopy using the CATERETÊ coherent-diffraction imaging beamline to spectroscopically isolate nanometer-sized volumes of soils. Success in these projects would provide novel tools at Sirius for research discoveries in soils and other hierarchical and heterogeneous materials that unpin a broad array of agricultural and environmental problems.

September 30, 2020

Dr. Andrew (Drew) Smith, Chief Operating Officer/Chief Scientist, Rodale Institute, Kutztown, PA,
Adoption of modern agricultural technology over the past 70 years or more has resulted in tremendous increases in crop production and reduced chronic malnourishment. However, this emphasis on yields has resulted in soil and environmental degradation and a decline in the nutritional concentrations of food. How this drop in nutritional quality has broadly affected human health is unknown but over that same time period the proportion of Americans with certain chronic diseases has risen whereby today close to half of all Americans have at least one chronic disease and half the global population suffers from “hidden hunger’ or nutritional deficiency despite caloric sufficiency. To explore the link between how food is grown, soil health, and human health, Scientists at Rodale institute have begun measuring the nutritional quality of grains grown in the Farming System Trial. The Farming Systems Trial is a 40-year long side-by-side comparison of organic and conventional grain cropping systems. In 2008, no-till was included as an additional treatment in all systems. While soil measurements indicate that tillage is not affecting soil health, recent nutrient testing in oats and wheat that included measurements of minerals, protein, amino acids, vitamin B6, calories, and a powerful nutraceutical – ergothioneine – suggest a relationship between tillage,  protein, and ergothioneine concentrations in grain.  Ergothioneine is exclusively biosynthesized by fungi and certain mycobacteria, actinobacteria and cyanobacteria in the soil and acquired in humans exclusively through the diet. The human health benefits of ergothioneine is currently an active area of research in the medical community and for those reasons we consider it a model compound to test the link between soil health and human health.

September 23, 2020

David Ramotowski, M.S. Student: SSC; Dept. of Crop & Soil Sciences, NCSU

The Effects of Nitrification Inhibitors on Nitrification and Associated Microbial Functional Guilds, Diversity, and Function


Nitrate is a major source of N nutrition for plant production, yet it is prone to losses from the soil via leaching and denitrification.  Chemicals that inhibit biological NO3 production, known as nitrification inhibitors (NIs) or N stabilizers, can be used to minimize soil NO3 accumulation; however, their efficacy and non-target effects vary. This experiment aimed to gauge the effectiveness of two NIs (VLS, an experimental NI from Verdesian Life Sciences and Instinct II, a commercially available NI from Corteva Agriscience) in inhibiting soil nitrification as well as influences on target and non-target microbial diversity and composition .  Two Hastings silt loams of different acidities from southern Seward County, NE, were evaluated in a microcosm incubation experiment over 63 days.  There were six treatments:  control soils; soils plus (NH4)2SO4 at 4 µg g-1 soil; soils with one of the two NIs; and soils with (NH4)2SO4 soil plus one of the two NIs.  Soil samples were taken at Days 0, 7, 14, 28, 42, and 63 to determine soil NH4 and NO3 concentrations.  Potential rates of nitrification were also measured at each interval. At the end of incubation, soil DNA was extracted, and population sizes of microbial guilds involved in nitrification and denitrification were measured by quantitative PCR.  Marker-gene high-throughput sequencing was also conducted to probe bacterial and fungal community composition.  The efficacy of VLS was comparable to Instinct II, as both retained about 80% of inorganic N in the form of NH4.  Based on the N mass balance, it seems that VLS might promote soil organic N mineralization or N loss via gaseous emissions, because NH4 was found to be greater in soils with VLS addition, and NO3 was very similar for both NIs.  Quantitative PCR and next-generation sequencing data are being processed and will contribute to comprehensive evaluation of the impacts of NIs on soil processes and sustainability.


September 16, 2020

Dr. Sierra Young, Asst. Prof., Dept. of Biological and Agricultural Engineering, NCSU,

From Farm to Takeoff: Aerial Robots for Visual and Physical Sensing in Agricultural Applications

(Due to technical difficulties the first part of the seminar is missing)

Biological and agricultural environments are dynamic, unstructured, and uncertain, posing challenges for data collection at the necessary spatial and temporal scales to enable meaningful systems analysis. Small unpiloted aerial systems (UAS), however, can overcome some of these challenges by enabling autonomous or human-assisted remote and in situ data collection. This talk will present a suite of technologies that leverage robotics, mechatronics, and computer vision to broaden sensing and sensemaking capabilities across different types of environments. Demonstrative case studies will be presented, including UAS-assisted hydrologic assessment, in situ soil moisture estimation, and aerial manipulation, with a focus on their potential in precision agriculture. The material covered in this talk will illustrate how the strategic, user-focused design of aerial robotics and automated systems to overcome unique data collection challenges can enable better understanding and decision-making for dynamic biological and agricultural systems.

September 9, 2020

Dee Webb, State Statistician for NC, NC Field Office, USDA National Agricultural Statistics Service (NASS),

will present via Zoom a seminar titled:

NASS – Statistics in Service of U.S. Agriculture

As the statistical agency for the USDA for more than 150 years, the National Agricultural Statistics Service (NASS) is the official source of primary, comprehensive, current information on the farms and people who provide food, feed, and fiber to our nation and the world. NASS conducts hundreds of surveys every year and prepares reports covering virtually every aspect of U.S. agriculture. And NASS is committed to providing timely, accurate and useful statistics in service to U.S. agriculture. To uphold this mission statement NASS publishes reports on agriculture across the U.S., provides objective and unbiased statistics, conducts the Census of Agriculture every five years, serves local needs through State field offices, and safeguards privacy of producers with a guarantee that confidentiality and data security are top priorities. This seminar presented by Dee Webb, USDA/NASS NC State Statistician will provide an overview of NASS, highlight the Quick Stats tool available to search the NASS database and discuss the Talking about NASS guide developed to help partners communicate more effectively about the NASS mission and the value of the data


September 2, 2020

Dr. Nidhi Rawat, Assist. Prof., Dept. of Plant Sciences and Landscape Architecture, University of Maryland,  presented a seminar via Zoom titled:

“Developing Multi-Pronged Strategies to Overcome the Fungal Pathogens of Wheat”

Crop diseases challenge the yield and quality of agricultural produce worldwide. To meet the increasing demand on crop production due to rising global population, losses due to diseases need to be reduced. Working with wheat, a major global food crop, we are developing multi-pronged approaches to overcome fungal pathogens. Research on some of these strategies will be presented in the talk.


August 27, 2020

Dr. Matthew Vann, Asst. Prof., Dept. of Crop and Soil Sciences/NCSU,

“From Seed to Smoke – My Journey to Sustain North Carolina’s Oldest Cash Crop”

North Carolina has a longstanding reputation for producing the highest quality tobacco in the world; however, this notoriety is not earned absent of grand challenges. Since 2015, the Tobacco Research and Extension Program in the Department of Crop and Soil Sciences, led by Dr. Matthew Vann, has invested significant effort into sustaining this industry by conducting applied research that addresses the many needs of the modern tobacco farmer, educates the next generation of tobacco farmers and scientists, and readily shares new information with the current body of commercial farmers and Extension Agents. This seminar will outline Dr. Vann’s efforts to sustain North Carolina’s oldest and most economically important crop.


August 26, 2020

Hannah Frank, M.S. Student: Soil Science; Dept. of Crop and Soil Sciences, NCSU,

“Involvement of the Ectomycorrhizal Fungi Hebeloma cylindorosporum and Paxillus ammoniavirescens in Potassium Uptake of Loblolly Pines.”

Ectomycorrhizal relationships are critical ecological mutualisms involving plant hosts and soil fungi. Both organisms utilize their respective advantages to obtain necessary nutrients from their symbiotic partner; the plant provides C to the fungus in exchange for water and/or nutrients. The role of ectomycorrhizal fungi in plant K uptake has yet to be investigated as thoroughly as N and P uptake. The aim of this research is to better understand the role of two ectomycorrhizal fungi, Hebeloma cylindrosporum and Paxillus ammoniavirescens, in K transport to loblolly pines (Pinus taeda). This project has three components. First, using Rb, an effective K tracer, to track K transport to the plants through the fungal hyphae. Preliminary data shows extremely high colonization rates of both fungi and no significant differences in biomass. Forthcoming nutrient analysis will reveal more. The second component is tracking C allocation from the plant to the fungus through 13C. We’ve developed a split-root system to have two separate sections of root colonized by fungi with access to different levels of K. The final part of the project is performing RNA sequencing of seedling roots colonized with each fungus and grown in high/low K conditions. The purpose of the sequencing is to identify putative K transporter candidates from P. taeda differentially regulated during the symbiosis. Thoroughly understanding how naturally occurring plant-fungal relationships in the soil improve plant nutrition offers opportunity for tapping into these networks more to decrease the need for fertilizer inputs. A better understanding of these relationships and their mechanisms holds potential for respecting their ecological significance and utilizing their nutrient optimization