Research Project: Sustainable Agricultural Systems for the Northern Great Plains

Location: Northern Great Plains Research Laboratory

2021 Annual Report

Objectives
Objective 1: Develop strategies to increase production and selected non-provisioning ecosystem services while increasing socio-economic performance of grazing, crop, and integrated crop/livestock systems. Objective 2: Develop options for integrated agricultural systems that reduce production risks, and enhance economic viability and ecosystem services under extreme weather conditions. Objective 3: Assess the effects of management strategies aimed at enhancing ecosystem services on the nutrient content of crop and livestock products. This objective will be enhanced by including research on the plant physiological changes that may affect nutrient density of crops, according to the following subobjective: Subobjective 3C: Evaluate the impact of management strategies including use of phytochemical-rich cover crops and pulse crops on soil and plant function and linkages to crop and meat nutrient density and functional quality. New Subobjective 3D: Identify and quantify plant responses to soil management and abiotic and biotic stresses that affect crop and forage productivity, nutrient density, and functional quality. Objective 4: Operate and maintain the Northern Great Plains LTAR network site using technologies and practices agreed upon by the LTAR leadership. Contribute to the LTAR working groups and common experiments as resources allow. Submit relevant data with appropriate metadata to the LTAR Information Ecosystem. Objective 5: Improve the social and economic sustainability of food production systems for current and future climates in the northern states.

Approach
Agriculture not only faces the challenge of meeting growing needs for food, feed, fuel, and fiber, but also providing non-provisioning ecosystem services while adapting to variable weather conditions. This project builds upon previous research at the Northern Great Plains Research Laboratory (NGPRL), by continuing and expanding research on how management scenarios can impact ecosystem services, but also evaluating the effect of management on nutrient concentrations and providing ways to scale the research to landscape and national levels. The project will continue to develop sustainable management strategies for crops and livestock while using this knowledge to develop more efficient crop-livestock systems (Objective 1). Through collaboration with other ARS locations, NGPRL will determine how different management strategies affect nutrient concentration in crops and carcass quality in livestock (Objective 3). Modelling will be used to scale findings at the plot or field scale to landscape or regional levels and to explore potential management options for producers under variable weather conditions (Objective 2). Finally, NGPRL is involved in multiple national networks, including the National Ecological Observatory Network (NEON) and the Long Term Agroecosystem Research (LTAR) network, which allow network collaborations to leverage local expertise and scale and share research findings at a national level. The NGPRL is uniquely suited to conduct this multitier research because it has a diversity of landscapes and disciplines in which conduct these multiple approaches to sustainably intensify agriculture. We anticipate that completing this project plan will produce contributions to network databases and also guidelines for developing sustainable integrated agricultural systems. Outcomes from the project will benefit producers, the scientific community and policy makers by producing guidelines and management options.

Progress Report
Objective 1. Subobjective 1A. All the treatments were implemented this year, including: 1) grazing at a moderate stocking rate, 2) mob-grazing with cattle only, 3) mob-grazing of cattle followed by browsing by goats, 4) fall fire, and 5) fall fire that is grazed by cattle the following spring, completing the initiation of the treatments. All plots were burned in October 2020 and grazing was implemented on all plots beginning in May 2021. All plots were burned in October 2020 and grazing was implemented on all plots beginning in May 2021. After discussions with the focus group for this objective, the area of the control plots was reduced to better reflect local practices. The extreme regional drought impacted forage production and therefore grazing times. This was most noticeable on the control treatments where livestock began to be removed 1 and ½ months before the previous year’s removal date. Collaborations continue with the Sidney, Montana, location to evaluate the impacts of the treatments on grasshopper and dung beetles. Subobjective 1.B. Research continued on experiment 1.B.1. after analyzing data from the first 12 years of the study and evaluating whether to continue the study, as was planned in the study design. After evaluation, it was determined that the experiment would be continued, but with modified treatments implemented in Fiscal Year (FY) 2021. The spring wheat - pea and spring wheat - pea/cover crop rotation plots were merged into a four-year rotation of spring wheat – pea – corn – canola. The spring wheat – pea – corn rotation was changed to a spring wheat – pea/canola – corn rotation. As mentioned in last year’s annual report, treatments in 1.B.2 were modified and the area was planted to perennials in FY 2019. Data continues to be collected off the perennials to determine the impact of previous cropping system on perennial establishment and productivity. Experiment 1.B.3 continued with monitoring the establishment of Kernza, which was planted in FY 2020. Due to continued extreme dry conditions, it was decided to delay alfalfa planting, which had been scheduled for FY 2021 to FY 2022. Research on experiment 1.C.1 was evaluated at the end of FY 2020 as was planned in the study design, and it was determined that the current treatments would not be continued. The site will be maintained in a wheat – corn – soybean rotation for at least two years to prepare the site for initiating new treatments. During this period micro-plots were established to investigate effects of previous management on wheat production and nutrient content, in support of Objective 3. Objective 2. Subobjective 2.A. Research on experiment 2.A.1 continued after calibrating Environmental Policy Integrated Climate (EPIC) on historical crop production data, and completing initial model simulations under climate projection scenarios. Growth curve data have been collected on rangelands for two years, one of which included a drought. Results have been simulated using the Rangeland Hydrology and Erosion Model (RHEM). The grazingland Agricultural Policy Environmental eXtender (APEX) model is no longer being supported so parameters were entered into the National Academies of Sciences, Engineering and Medicine (NASEM) – beef cattle nutrient requirements model instead to examine nutritional quality of Kentucky bluegrass relative to nutrient requirements of cow/calf pairs during the grazing season over 2 grazing seasons. Subobjective 2.B. Treatments have been maintained for an additional year and data collected. A North Dakota State University graduate student has begun to analyze the numbers of axillary buds under the different treatments and will continue to collect data through the fall. Objective 3. Subobjective 3.A. As mentioned in Objective 1.C, micro-plots were established in experiment 1.C.1 to investigate the genetics x management interaction on selected soil and plant quality aspects. The location continues its collaboration with Fargo and Grand Forks, North Dakota, focused on the Healthy Soils-Healthy Food-Healthy People Initiative. North Dakota State University is also collaborating on this project to provide expertise in soil microbiology. As mentioned in the FY 2020 annual report, Subobjective 3.B was discontinued because after multiple attempts, heifers could not reach a satisfactory weight for finishing prior to grazing them on the integrated crop-livestock experiment (Experiment 1.C.1). Two new subobjectives were added to Objective 3 with funding increases in the FY 2020 and FY 2021 cycles. The focus of Subobjective 3.C is to evaluate the impact of management strategies including use of phytochemical-rich cover crops and pulse crops on soil and plant function and linkages to crop and meat nutrient density and functional quality. Subobjective 3.D focuses on identifying and quantifying plant responses to soil management and abiotic and biotic stresses that affect crop and forage productivity, nutrient density, and functional quality. Objective 4: Research on the plot-scale and field-scale cropland common experiment continued as planned. Subobjective 4A. Assessments were conducted at both plot and field scales for the Long-Term Agroecosystem Research Network Croplands Common Experiment. Relevant plant, soil, air, and imagery samples were collected along with applicable metadata. Fields included in the experiment are part of the National Wind Erosion Research Network (NWERN) and site data were collected and shared with NWERN. Objective 5. New funding was received in FY 2021 and a new objective (Objective 5) was established focusing on improving the social and economic sustainability of food production systems for current and future climates in the northern states. ARS Mandan developed a position description to recruit a sociologist at its location.

Accomplishments
1. Nitrous oxide emission in integrated crop-livestock system. Integrated crop-livestock systems can improve profitability and production but their effect on environmental variables is less clear. Among the many important environmental attributes associated with agricultural production, nitrous oxide emission is prominent for its dual role as a strong greenhouse gas and its capacity to deplete ozone in the stratosphere. ARS scientists at Mandan, North Dakota, measured nitrous oxide emission from integrated crop-livestock and crop-only practices over a 3-year period. Cumulative nitrous oxide emission was not different between practices. However, nitrous oxide emission was greater in corn and spring wheat phases of the rotation compared to soybean and cover crop phases. Study outcomes suggest producers could reduce nitrous oxide emission by over 50% by growing grass dominant cover crops compared to corn and spring wheat in integrated crop-livestock systems.

2. Residue retention and grazing increased soil carbon in cropland. Integrated crop-livestock systems have the potential to balance production and environmental goals by improving the soil. Soil organic carbon is a key indicator of the soil’s capacity to efficiently cycle nutrients, retain water, and support soil biota. However, few studies have evaluated integrated crop-livestock system effects on soil carbon in semiarid regions, where changes in soil properties occur slowly. Through a strategic investment in long-term research, ARS scientists at Mandan, North Dakota, found greater soil carbon in an integrated crop-livestock study where crop residue was grazed or left in place compared to where it was mechanically removed. Soil carbon also increased over time where crop residue was grazed or retained. Outcomes showed that retaining residues and livestock grazing are important strategies producers can use to increase soil carbon in integrated crop-livestock systems.

3. Grass pasture effective at protecting water quality in an integrated crop-livestock system. Integrated crop-livestock systems can enhance agricultural production, but their effects on water quality are unclear, particularly in semiarid regions. ARS scientists at Mandan, North Dakota, used rainfall simulations to examine water quality outcomes from wheat, cover crop, and grass pasture phases of a long-term integrated crop-livestock study. Surface runoff and percolation water had greater Nitrogen and Phosporus concentrations in cover crops and wheat compared to grass pasture. Nitrogen and phosphorus concentrations in water were greater before grazing compared to after grazing. Lower Nitrogen concentrations in water after grazing could be due to nutrient retention by vegetation, particularly in the cover crop and grass phases. These results are important for producers and policy makers to understand how adopting integrated crop-livestock systems could affect water quality in semiarid regions.

4. Net global warming potential from cropland increased with addition of beef cattle. Recent interest in integrated-crop livestock systems have prompted researchers to better understand ecosystem services associated with their management, but few studies have measured the effects on net global warming potential. ARS scientists at Mandan, North Dakota, conducted a multi-year study to determine the net global warming potential of integrated crop-livestock systems in a semiarid region. Net global warming potential was greater for grazed cropland compared to ungrazed cropland, due mostly to methane emissions from beef cattle in the former. However, both production systems resulted in net greenhouse gas emissions to the atmosphere. Results are useful to producers, researchers, and policy makers in showing that more efficient input use and practices that more rapidly store carbon in the soil will be necessary to reduce greenhouse gas emissions in integrated crop-livestock systems.

5. A review of how plant secondary metabolites may enhance agricultural sustainability. All plants produce primary and secondary compounds. Primary compounds are associated with the growth of plants, while secondary compounds have various roles which improve ecological resiliency. ARS researchers from Mandan and Fargo, North Dakota, and a researcher from Utah State University compiled literature highlighting various benefits of plant secondary metabolites to agroecological systems. There is relatively little research that encompasses the benefits of plant secondary metabolites to soil, plants, animals, and ultimately humans. Weaving together the synergistic effects of these metabolites in agroecological systems is important to producers as it allows additional tools and management strategies to enhance agricultural sustainability.

6. Perennial forages influence mineral and protein concentrations in annual wheat cropping systems. There is increasing interest in the potential impact of agricultural land management on food nutritional quality. Few studies have attempted to make connections between food quality and land management practices. A no-till experiment in Mandan, North Dakota, looked at continuous annual fertilized spring wheat and unfertilized spring wheat planted following 2-5 years of perennial forages such as alfalfa and intermediate wheatgrass. ARS scientists from Mandan, Fargo and Grand Forks, North Dakota, analyzed wheat grain from this study for minerals and protein to see if there was an influence on food quality. Protein concentration was greater when wheat followed alfalfa, but otherwise concentrations of protein and minerals in wheat grain were similar between cropping systems. Also, when wheat yield increased, protein and mineral concentration of zinc, sulfur, nickel, phosphorous, potassium, and magnesium decreased. Differences in mineral concentrations between years of harvest were generally greater than between cropping practices. This suggests that it is important to understand the interaction of management and varying weather and environment on grain quality. These results are useful to producers and researchers in targeting management to increase nutrient content of wheat.

7. Late-season cover crops, planted after a cash crop, did not reduce subsequent crop yield in a semiarid environment. Interest in cover crops is growing among producers but information on how to incorporate them into crop rotations in limited, especially in the relatively short growing season of the northern Great Plains. ARS scientists in Mandan, North Dakota, evaluated the effect 18 different cover crop monocultures and mixtures, seeded in August following dry pea harvest, had on spring wheat, corn, soybeans and dry peas, seeded the subsequent year. Cover crops grown after dry peas did not impact the yield of cash crops the following year. However, the yield of cover crops was dependent on whether timely precipitation was received after planting. Cool-season cover crop monocultures were more productive than warm-season monoculture and some cover crop mixtures. The study is useful to producers in showing that cover crops could be grown after a short-season cash crop without negatively affecting subsequent cash crop yield, and provides information for selecting cover crops that are likely to be the most productive in that situation.

8. Plant-based imitation meat and grass-fed beef have large nutritional differences despite comparable Nutritional Facts panels. Plant-based imitation meat has become more popular and is commonly available. There is growing interest in whether plant-based meat alternatives are nutritionally comparable to actual meat. An ARS scientist in Mandan, North Dakota, collaborated with scientists at Utah State University and Duke University to analyze a popular plant-based alternative to grass-fed ground beef, and provided an in-depth comparison of the metabolite profiles of the two foods. Despite apparent similarities based on the simple information in their Nutritional Facts panels, the metabolite abundances between the plant- and animal-based foods differed by 90% with several metabolites found exclusively or in greater quantities in ground beef or the imitation meat. For example, vitamin B3, glucosamine and the anti-oxidants allantoin, anserine, cysteamine, spermine, and squalene were only found in ground beef; whereas, vitamin C, phytosterols, and several phenolic anti-oxidants were only found in the plant-based meat alternative. The study was important because it showed that a popular plant-based meat alternative and grass-fed ground beef had large differences in nutrients within various nutrient classes such as amino acids, vitamins, and fatty acids. Therefore, these foods should not be considered nutritionally interchangeable but rather complementary. The study did not determine if either food is healthier than the other to consumers.

Review Publications
Fuchs, K., Merbold, L., Buchmann, N., Bellocchi, G., Martin, R., Klumpp, K., Bindi, M., Brilli, L., Conant, R.T., Dorich, C.D., Ehrhardt, F., Soussana, J., Fitton, N., Smith, P., Grace, P., Liebig, M.A., Lieffering, M., Newton, P.C., Rees, R.M., Topp, C.F., Recous, S., Snow, V. 2020. Evaluating the potential of legumes to mitigate N2O emissions from permanent grassland using process-based models. Global Biogeochemical Cycles. 34. Article e2020GB006561. https://doi.org/10.1029/2020GB006561.
Clemensen, A.K., Provenza, F.D., Hendrickson, J.R., Grusak, M.A. 2020. Ecological implications of plant secondary metabolites - phytochemical correlations between soil, forages, herbivores and humans. Frontiers in Sustainable Food Systems. 4:233. https://doi.org/10.3389/fsufs.2020.547826.
Faust, D.R., Liebig, M.A., Toledo, D.N., Archer, D.W., Kronberg, S.L., Hendrickson, J.R., Bawa, A., Kumar, S. 2021. Water quality of an integrated crop–livestock system in the northern Great Plains. Agrosystems, Geosciences & Environment. https://doi.org/10.1002/agg2.20129
Hendrickson, J.R., Liebig, M.A., Archer, D.W., Schmer, M.R., West, M.S., Nichols, K.A., Tanaka, D.L. 2021. Late-seeded cover crops in a semiarid environment: Overyielding, dominance, and subsequent crop yield. Renewable Agriculture and Food Systems. 1-12. https://doi.org/10.1017/S174217052100020X.
Subhashree, S.N., Igathinathane, C., Liebig, M.A., Halvorson, J.J., Archer, D.W., Hendrickson, J.R., Kronberg, S.L. 2020. Biomass bales infield aggregation logistics energy for tractors and automatic bale pickers—a simulation study. Biomass and Bioenergy. 144:105915. https://doi.org/10.1016/j.biombioe.2020.105915.
Liebig, M.A., Faust, D.R., Archer, D.W., Christensen, R., Kronberg, S.L., Hendrickson, J.R., Lee, J., Tanaka, D.L. 2021. Integrating beef cattle on cropland affects net global warming potential. Nutrient Cycling in Agroecosystems. https://doi.org/10.1007/s10705-021-10150-9.
Sanderson, M., Liebig, M.A. 2020. Forages and the environment. In Moore, K.J., Collins, M., Nelson, J, Redfearn, D.D., editors. Forages, Volumne 2: The Science of Grassland Agriculture, 7th ed. John Wiley & Sons, West Sussex, UK. p. 249-259.
Liebig, M.A., Faust, D.R., Archer, D.W., Kronberg, S.L., Hendrickson, J.R., Aukema, K.D. 2020. Grazing effects on nitrous oxide flux in an integrated crop-livestock system. Agriculture, Ecosystems and Environment. 304:107146. https://doi.org/10.1016/j.agee.2020.107146.
Carr, P.M., Bell, J.M., Boss, D.L., DeLaune, P., Eberly, J.O., Edwards, L., Fryer, H., Graham, C., Holman, J., Islam, M.A., Liebig, M.A., Miller, P.R., Obour, A., Xue, Q. 2020. Annual forage impacts on dryland wheat farming in the Great Plains. Agronomy Journal. 113:1-25. https://doi.org/10.1002/agj2.20513.
Shrestha, P., Karim, R., Sieverding, H.L., Archer, D.W., Kumar, S., Nleya, T., Graham, C.J., Stone, J.J. 2020. Life cycle assessment of wheat production and wheat-based crop rotations. Journal of Environmental Quality. 49:1515– 1529. https://doi.org/10.1002/jeq2.20158.
Liebig, M.A., Faust, D., Archer, D.W., Kronberg, S.L., Hendrickson, J.R., Tanaka, D. 2020. Integrated crop-livestock effects on soil carbon and nitrogen in a semiarid region. Agrosystems, Geosciences & Environment. https://doi.org/10.1002/agg2.20098.
Van Vliet, S., Bain, J.R., Muehlbauer, M.J., Pieper, C.F., Kronberg, S.L., Provenza, F.D. 2021. A metabolomics comparison of plant-based meat and grass-fed meat indicates large nutritional differences despite comparable nutrition facts panels. Scientific Reports. 11:13828. https://doi.org/10.1038/s41598-021-93100-3.
Schillinger, W.F., Archer, D.W. 2020. Winter Triticale: A long-term cropping systems experiment in a dry Mediterranean climate. Agronomy Journal. 10(11):1777. https://doi.org/10.3390/agronomy10111777.
Clemensen, A.K., Grusak, M.A., Duke, S.E., Franco Jr, J.G., Hendrickson, J.R., Liebig, M.A., Roemmich, J.N., Archer, D.W. 2021. Perennial forages influence mineral and protein concentrations in annual wheat cropping systems. Crop Science. 61(3):2080-2089. https://doi.org/10.1002/csc2.20491.
Hosseini, M., McNairn, H., Mitchell, S., Dingle-Robertson, L., Davidson, A., Ahmadian, N., Bhattacharya, A., Borg, E., Conrad, C., Saliendra, N.Z. 2021. A comparison between support vector machine and the water cloud model for estimating crop leaf area index. Remote Sensing Reviews. 13:1348. https://doi.org/10.3390/rs13071348.