Impact of Soil Tillage Systems on CO2 Emissions, Soil Chemical Parameters, and Plant Growth Physiological Parameters (LAI, SPAD) in a Long-Term Tillage Experiment in Hungary

Choosing the most sustainable and ecologically stable soil tillage techniques requires dependence on long-term field trials, which are essential for successful interventions and evidence-based decision-making. This research evaluated several factors, including soil biological activity (CO2 emission), soil chemical properties (pH (KCl), soil organic matter (SOM)), plant growth physiological indicators (Leaf Area Index (LAI), Soil and Plant Analysis Development (SPAD)), crop yield, and grain quality (Zeleny index, protein %, oil %, and gluten % content), under six soil cultivation methods that represent varying degrees of soil disturbance in a long-term (23 years) tillage experiment. Conventional tillage (ploughing (P)) and conservational tillage techniques (loosening (L), deep cultivation (DC), shallow cultivation (SC), disking (D), and no-till (NT)) were examined for three years (2022, 2023, and 2024) in a winter barley–soybean–winter wheat cropping system. Results indicate that tillage intensity has a differential influence on soil biological parameters, with minor variations in SPAD values across treatments. The findings show significant variations in CO2 emissions, LAI values, and grain quality in certain years, likely due to the influence of P and L tillage treatments. The novelty of this study lies in determining that, although the short-term effects of soil tillage on crop physiological parameters and grain yield may be minimal under fluctuating climatic conditions, long-term tillage practices significantly influence existing disparities, underscoring the necessity for site-specific and climate-resilient tillage strategies in sustainable crop production.