Potential of conservation tillage, cover crops, and digestate application as integrated C farming practices for processing tomato

• Published in: Soil & tillage research 2024-12, Vol.244, p.106213, Article 106213
• Main Authors: Ardenti, Federico, Capra, Federico, Santelli, Stefano, Lucini, Luigi, Tabaglio, Vincenzo, Fiorini, Andrea
• Format: Article
• Language: English
• Subjects: Carbon farming; Conservation agriculture; Minimum tillage; Processing tomato; Soil quality; Strip tillage
• ISSN: 0167-1987
• DOI: 10.1016/j.still.2024.106213

Conventional soil management — based on intensive tillage and low input of organic material – negatively impacts soil quality via carbon (C) losses as carbon dioxide emissions (CO2), exacerbating the effect of climate change on agriculture. Carbon farming practices (CFPs), such as minimum tillage (MT) and strip tillage (ST), offer promising solutions to maintain soil fertility, sustain crop yields, and mitigate environmental impacts. However, applying CFPs in processing tomato (Solanum lycopersicum L.) cropping presents unique challenges due to specific crop and tillage characteristics. Our two-year field study investigated the effects of conservation tillage practices (i.e., MT and ST), both combined with cover crops and digestate application, on soil quality parameters and processing tomato yield. The field studies were conducted in fields with varying soil textures (i.e., clay and silty clay loam), and aimed to evaluate responses in terms of soil C sequestration, nutrient concentrations, soil structure, and abundance of earthworms. We hypothesized that both MT and ST would enhance soil quality parameters also in tomato cropping systems, with ST potentially outperforming MT in C sequestration. Results revealed that CFPs significantly increased soil organic matter, total nitrogen, and available phosphorous compared with conventional tillage. Both MT and ST increased soil C sequestration (up to 1.06 Mg C ha−1 y−1 and 1.21 Mg C ha−1 y−1, respectively) compared with conventional tillage (CT), which lost around 0.88 Mg C ha−1 y−1 under silty-clay loam soil, and had negligible C sequestration (+0.02 Mg C ha−1 y−1) under clay soil. We found no significant difference between MT and ST when using the equivalent soil mass method for calculating C sequestration. Noteworthy, CFPs enhanced fertility parameters without a negative impact on yields, underscoring their potential for enhancing soil C sequestration, improving nutrient availability, and supporting processing tomato yield under adaptation scenarios to climate change. •Carbon farming practices enhance chemical, physical, and biological soil quality.•Combining digestate and cover crops with minimum tillage or strip tillage sequestered 0.83–1.63 Mg C ha−1 y−1.•ST outperforms MT for C sequestration potential with FD method, while not with ESM method.•Processing tomato yield was never negatively affected by carbon farming practices.