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Soil health is a key element in enhancing agricultural production, environmental sustainability, and food system resilience (Farnsworth 2015; Stevens 2018). The USDA Natural Resources Conservation Service (NRCS) defines soil health as “the continued capacity of soil to function as a vital living ecosystem that sustains plants, animals, and humans” (Pankhurst et al. 1997; Farnsworth 2015; Bowman et al. 2016). A common theme points to soil health as an indicator of the soil’s ability to support life, withstand environmental stresses, and endure as an important part of a resilient ecosystem. Because one of the key individual components of soil health is carbon (C) in organic matter (Idowu et al. 2009; Morrow et al. 2016), enhancing soil health also has a prominent role to play in addressing climate change (Stockmann et al. 2013; Schipanski et al. 2014; Paustian et al. 2016). Improving soil health is a natural climate solution (NCS) that increases C storage in soils (Poeplau and Don 2015; Griscom et al. 2017; Jian et al. 2020). Given soil health’s key role in sustaining agricultural productivity and enhancing C storage, there is significant interest in promoting …

The incorporation of swine manure with tillage effectively reduces ammonia (NH3) emissions and conserves crop available nitrogen (N) but is not compatible with no-till and many other conservation tillage programs. Rolling-tine aerators potentially provide a means to enhance manure infiltration with limited disruption of the soil surface; however, the impact of the range of aerator configurations and manure placements has not been widely studied. We measured NH3 emissions, conducted presidedress nitrate (NO3) tests (PSNT), monitored corn (Zea mays L.) grain yield when swine manure was incorporated with combinations of two aerator toolbar offset angles (0° and 10°) and two manure placements (broadcast before aeration and banded behind aerator), and compared those measurements to unincorporated surface application and an unmanured control. Additional plots were established with five rates of mineral N fertilization to determine N response curve and estimate fertilizer N equivalent of the applied manure. Measurement of cumulative NH3 emissions using a dynamic chamber method showed that offsetting the aerator toolbar by 10° reduced emissions by 65% to 75%, with both manure placements, compared to surface application. However, no consistent reductions in NH3 emissions were observed when the toolbar was not offset. While reduction in NH3 with the offset toolbar could conserve substantial amounts of plant available N, the soil disturbance caused by the offset tines would not be compatible with most conservation tillage programs. Presidedress NO3 test values increased when NH3 emissions were reduced. In 2009, both the angled and straight aerator treatments with manure banded behind the aerator resulted in significantly higher corn grain yield than all other treatments despite reductions in NH3 emissions only when the toolbar was angled. Correlation of yield from manure application treatments with the N response curve for multiple mineral N application rates showed a greater than expected response to manure application. Yield responses are an indication that aeration has benefits in addition to N conservation. We do not recommend the rolling-tine aerator if reducing NH3 emissions in conservation tillage is the primary goal, but future study into other yield-increasing benefits of aeration is needed.

Management decisions both at the field and off-site have the potential to contrib- ute to climate change mitigation and adaptation. Climate change threatens to increase the potential for soil erosion, reduce soil quality, lower agricultural productivity and negatively impact food security and global sustainability, making it one of the most severe challenges we will face in the 21st century. This paper looks at the potential of management to help us, not only mitigate climate change, but also to help us adapt to a changing climate. Different aspects of carbon management, nitrogen management, manure management, management in low-input systems (sustainable agriculture), and grazing land management are discussed as examples. Management decisions regarding conservation practices, such as no-till, con- servation agriculture, and returning crop residue to the field to increase nutrient cycling, can contribute to carbon sequestration and help us mitigate and adapt to climate change. Additionally, management of grasslands, restoration of degraded/desertified lands, nitrogen management to reduce greenhouse gas emissions, precision conservation management at a field and/or watershed level, and other management alternatives can also help us mitigate and/or adapt to climate change. Management for climate change mitigation and adaptation is key for environmental conservation, sustainability of cropping systems, soil and water quality, and food security. This paper suggests, based on a review of the literature, that management decisions that reduce soil erosion, increase carbon sequestration to improve soil functions, soil quality, and soil health, and contribute to the resilience of soils and cropping systems will be needed to respond to climate change and related challenges such as food security. Our review suggests that without management decisions that increase soil and water conservation, food security for the world's growing population will be harder to achieve.