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Farmers and policy makers pursue management practices that enhance water quality, increase landscape flood resiliency, and mitigate agriculture's contribution to climate change, all while remaining economically viable. This study presents a holistic assessment of how two practices influence the supply of these ecosystem services—the use of an aerator prior to manure application in haylands, and the stacked use of manure injection, cover crops, and reduced tillage in corn silage production. Field data are contextualized by semi-structured interviews that identify influences on adoption. Causal loop diagrams then illustrate feedbacks from ecosystem services onto decision making. In our study, unseen nutrient pathways are the least understood, but potentially the most important in determining the impact of a practice on ecosystem services supply. Subsurface runoff accounted for 64% to 92% of measured hydrologic phosphorus export. Average soil surface greenhouse gas flux constituted 38% to 73% of all contributions to the equivalent CO2 footprint of practices, sometimes outweighing carbon sequestration. Farmers identified interest in better understanding unseen nutrient pathways, expressed intrinsic stewardship motivations, but highlighted financial considerations as dominating decision making. Our analysis elevates the importance of financial supports for conservation, and the need for comprehensive understandings of agroecosystem performance that include hard-to-measure pathways. [ABSTRACT FROM AUTHOR]

Reference 1 Porterfield K.K., Joblin R., Neher D.A., Curtis M., Dvorak D., Curtis M., Dvorak S., Rizzo D.M., Faulkner J.W., Roy E.D. Upcycling Phosphorus Recovered from Anaerobically Digested Dairy Manure to Support Production of Vegetables and Flowers. The changes are as follows: Replacing Figure 4 Graph: Figure 4 Seedling dry biomass by amendment and application rate (mean ± 1 SD). Upcycling Phosphorus Recovered from Anaerobically Digested Dairy Manure to Support Production of Vegetables and Flowers. [Extracted from the article]

Dissolved air flotation (DAF) separates phosphorus (P)-rich fine solids from anaerobically digested dairy manure, creating opportunities to export surplus P to the marketplace as a bagged plant food product. Seedlings of tomato and marigold were amended at various volume per volume (v/v) ratios with plant foods consisting of fine solids upcycled (i.e., transformed into a higher quality product) by drying and blending with other organic residuals. A plate competition assay was conducted to assess the fine solids' potential to suppress the plant pathogen Rhizoctonia solani. Plant foods were comprised of 2.0–2.1% N, 0.8–0.9% P and 0.6–0.8% K. Extractions indicated that plant foods contained a mixture of plant-available and slow-release P. At 6% v/v plant food, dry biomass of marigold and tomato were six-times greater than the unamended control and not significantly different from a market alternative treatment. Fine solids exhibited negligible potential to suppress R. solani. This study indicates that DAF-separated fine solids could be used to support horticulture, providing information for design of a circular economy approach to dairy manure nutrient management. Life cycle assessment and business model development for this nutrient recovery strategy are necessary next steps to further guide sustainability efforts. [ABSTRACT FROM AUTHOR]