Impact of conventional, organic and regenerative vineyard management on soil quality

Abstract

Soil health plays a critical role in sustainable vineyard management, influencing both productivity and long-term ecological resilience. This study compared soil chemical and biological properties across three vineyards in the Columbia Gorge AVA, United States: conventionally managed (CV), organically managed (OR), and regeneratively/biodynamically managed (RG) with additional insights on variation between Row and Inter-row zones. Composite soil samples (n = 3 per vineyard) were collected and analyzed for nutrient availability (P, K, Ca, Mg, Cu, etc.), microbial activity (CO₂ burst, PMN, microbial biomass), and organic matter (OM). Due to small sample sizes and non-normal distributions, nonparametric statistical tests were applied (Kruskal–Wallis, Mann–Whitney U, and Wilcoxon Signed-Rank). Results indicated significantly higher OM, Cu, and P in the OR and RG systems compared to CV, with Inter-row zones generally exhibiting greater microbial activity and OM content than Rows. These findings suggest that soil biological and chemical properties are shaped by management practices, with organic and regenerative systems enhancing key indicators of soil health. The results provide evidence that ecologically focused management may support more resilient and functionally active vineyard soils in semi-arid, Mediterranean type growing conditions.