Issue link: https://www.e-digitaleditions.com/i/1413164
Soil Health: Deriving Benefits From the Ground Up The concept of "healthy soil" has become increasingly popular over the last decade as researchers, government agencies, organizations like the Almond Board and farmers continue learning more about the essential role soil plays in crop productivity, air and water quality, climate regulation and human health. Soils are complex and living ecosystems capable of supporting a wide range of functions through the activities of soil organisms (Figure 1). Among other benefits, a well-functioning soil ecosystem can: promote the retention and availability of crop nutrients, build soil structure to reduce topsoil loss, alleviate compaction, improve infiltration and soil water holding capacity and build and sequester carbon. Additional benefits for healthy soils Healthy soils have the potential to not only play a central role in individual almond orchards but also support industry-wide efforts to achieve Almond Orchard 2025 Goals. A healthy soil ecosystem in the orchard can help growers collectively advance toward specific goals such as improving water and nutrient use efficiency, recycling almond coproducts and reducing dust to improve air quality. And these numerous benefits that ultimately contribute to long- term orchard sustainability goals often do not come at the expense of productivity. In fact, a growing number of studies suggest we can build healthy soils that support multiple benefits while maintaining or, in some cases, improving crop yields. Spreading the word about healthy soil ecosystems Identifying the strategies for how to build healthy soils and enhance soil ecosystem functions are still being established for almond orchards. To address this knowledge gap and start developing best management practices for growers, a collaborative team of UC Davis researchers and a UC Agriculture and Natural Resource extension specialist are aiming to better define healthy almond orchard soil in the Sacramento Valley and identify practices already being used to improve orchard soil health. Although the research was explicitly conducted in the Sacramento Valley region, more regional work to explore soil health best management practices is needed across California as almond producing regions vary widely in regards to soil types and climates. The research team selected 23 orchards across the Sacramento Valley region that represent a variety of management, scales of operation and farm goals (Figure 2) to capture the diverse challenges and innovative solutions used by California almond growers. RESEARCH UPDATE Soil supports a wide range of organisms Pill bugs help build soil structure and promote nutrient cycling by shredding & decomposing residue. Soil microbial communities, including fungi and bacteria, are the main engines of soil ecosystem as they contribute substantially to many functions. Finally, earthworms are engineers of the soil because they build soil structure. In addition, they promote nutrient cycling by decomposing plant residues. Figure 1 Written by Krista Marshall, PhD Candidate, UC Davis 17