Farm‐level variability in soil biological health indicators in Michigan is dependent on management and soil properties

Abstract

AbstractSoil biology is vital for maintaining productivity, enhancing soil health, and creating resilient agroecosystems. However, many questions remain on how microbial communities are impacted by different soil properties and management practices, especially on grower‐managed fields. This study examined soil biological health properties (0–15 cm) and field history data from 310 grower‐managed fields within Michigan between Fall 2019 and Spring 2021. The objectives were to evaluate the impact of soil texture, tillage, and crop diversity on microbial populations and examine the relationship between soil health indicators and microbial community. Phospholipid fatty acid analysis was used to estimate total microbial abundance and composition of broad taxonomic groups like bacteria, fungi, arbuscular mycorrhizal fungi, actinomycetes, and eukaryotes. Other soil health indicators measured were organic carbon, permanganate oxidizable carbon, potentially mineralizable nitrogen, phosphorus, calcium, potassium, magnesium, and water‐stable aggregation. Soil texture did not significantly influence microbial community except for actinomycetes, which were significantly higher in fine‐textured soils. Tillage had the largest influence on microbial communities, with significantly lower values for all microbes in tilled compared to no‐till fields. Crop diversity had a minimal impact, affecting only arbuscular mycorrhizal fungi and eukaryote populations. All measured soil health indicators were positively associated with microbial populations except for phosphorous, which had a negative correlation (r = −0.56 to −0.66). Overall, we conclude that tillage is the dominant driver of soil biological health on grower‐managed fields across Michigan. Consequently, adoption of no‐till management practices where possible can help restore soil health and long‐term sustainability in agroecosystems.