Opportunities to implement manureshed management in the Iowa, North Carolina, and Pennsylvania swine industry

Abstract

The U.S. swine industry is diverse, but opportunities exist to strategically improve manure management, especially given much of the industry's vertical integration. We investigate opportunities for improving manureshed management, using swine production examples in Iowa, North Carolina, and Pennsylvania as a lens into historical trends and the current range of management conditions. Manure management reflects regional differences and the specialized nature of hog farms, resulting in a large range of land bases required to assimilate manure generated by these operations. Selected representative farm scenarios were evaluated on an annual basis; farm‐level manuresheds were largest for Pennsylvania sow farms and smallest for North Carolina nursery farms. Compared with nitrogen‐based manuresheds, phosphorus‐based manuresheds were up to 12.5 times larger. Technology advancements are needed to promote export of concentrated nutrients, especially phosphorus, from existing “source” manuresheds to suitable croplands. The industry is dynamic, as revealed by historical analysis of the siting of hog barns in Pennsylvania, which are currently trending toward the north and west where there is greater isolation to prevent the spread of disease and a larger land base to assimilate manure. Industry expansion should focus on locating animals in nutrient “sink” areas.

Envisioning the manureshed: Toward comprehensive integration of modern crop and animal production

“…Similarly, Meinen et al. (2022) identify distinctly regional patterns in the geographic migration of hog farms to the interspaces between poultry hotspots, with hog farms moving to places where productive lands can best use their manure and where regional residents are more supportive of their presence. Examples such as these exploit the regional organization of transportation networks (Day‐Farnsworth & Miller, 2014), as well as the “sense of place” (Jorgensen & Stedman, 2001) by which residents within a region can envision opportunities for manure recycling.…”

“…(2022) and Meinen et al. (2022) document opportunities for implementing manuresheds in systems where grazing is absent. Through standardization, coordination, and contracts, poultry and hog industries offer predictability and scalability that has great potential for deliberate, strategic management needed to maintain manuresheds.…”

“…An overarching challenge facing manureshed implementation is standardization, required to achieve goals of scaling as a predictable input into crop production systems. Because animal production systems are in a constant state of evolution and vary widely within individual industries, there are limits to easy generalization of approaches to implement manureshed management (Dell et al., 2022; Meinen et al., 2022; Spiegal et al., 2022b). Even definitions of animal manure types can be difficult to pin down, as exemplified by the terms “dry,” “liquid,” “slurry,” “solid,” and “semi‐solid” that may be defined consistently within certain contexts but lack universal consensus (e.g., Lorimor et al., 2004).…”

Toward a Robust Land Suitability Framework for Manure Management: Modeling Impacts and Evaluating Biophysical Characteristics

“…A detailed assessment of nutrient loss from manure application is required to evaluate the potential of manure as the right nutrient source and the effectiveness of the LSF (Saha et al 2018(Saha et al , 2020. Quantitative estimates of nutrient loss from various landscapes also provide opportunities to design sustainable livestock systems with optimal manure utilization and implement circular nutrient conceptbased agricultural systems (Meinen et al 2022).…”

“…Quantitative estimates of nutrient loss from various landscapes also provide opportunities to design sustainable livestock systems with optimal manure utilization and implement circular nutrient concept‐based agricultural systems (Meinen et al. 2022).…”