We used 352 published data points to develop multivariate linear regression, regression tree, and random forest models that predict the chemical composition of light oil from hydrothermal liquefaction of biomass. The mean absolute error calculated from ten-fold cross-validation indicates the random forest model had the best predictive ability, followed by regression tree and multivariate linear regression models. The random forest method is also more scalable than multivariate linear regression for data points outside the range of the dataset. The decision tree methods yield minimal information for improving understanding of the HTL process chemistry. Multivariate linear regression, on the other hand, identified previously unknown ternary interactions. For example, interactions involving lipid, lignin, and protein increase the abundance of N-containing compounds in the light oil. Further experimentation with lipid, lignin, and protein model compounds showed the formation of large amounts of undesirable long-chain amides in oil. This work shows that using multiple statistical models can further deepen the understanding of the HTL process in addition to providing tools that predict process outcomes.

The climate crisis has long been a looming threat. While focus has been on carbon dioxide, nitrous oxide is a potent greenhouse gas with 298 times the warming potential of carbon dioxide and deserves attention. Almost three quarters of nitrous oxide is emitted from agricultural soil management, including the use of nitrogenous fertilizers. The inherent connection between agriculture and climate not only reveals the problems but also the solutions. Managing soil health especially nitrogenous compounds can reduce nitrous oxide emissions, fertilizer input, and costs to farmers.Concerns about climate are directly tied to food production, and a growing population will only exacerbate the situation: approximately half of food production currently relies on fertilizers, and the expected doubling of food demand in the forthcoming years will augment this reliance on fertilizers for sustaining and increasing yields. Now, more than ever, understanding and preserving soil nutrient health with relation to fertilizer use is necessary.While conservation efforts have been made, there is a lack of attention toward fertilizers and nitrous oxide. This article explores the technological advancements of the field including biotechnology, electrochemistry, enhanced fertilizer products, and farming practices that have the potential to limit fertilizer use, reduce nitrous oxide emissions, and create greener fertilizer production processes. Policy and research gaps are unraveled to reveal that the federal government should address these issues through the following policy recommendations:1. Improving Current USDA Conservation Programs. Increasing access to current conservation programs and measuring effectiveness of these programs.2. Farm Bill Updates for 2023. Reauthorizing the Farm Bill to include appropriations for market creation and adaptation, increasing nutrient management plans, and standardized labeling.