Regenerative soil treatments with alginite, mulch, and cover crops under minimum tillage: Impacts on soil organic matter content and quality in a 3-year study

The degradation of arable land globally, largely due to declining soil organic matter (SOM), is a pressing issue. SOM is essential for various soil functions and significantly influences soil quality and health. Our study aimed to compare soil regenerative management methods for soil quality and basic essential functions and their effectiveness. We focused on selecting methods suitable for effectively monitoring changes during soil management. Over 3 years, we employed core methods, including minimum-till practices and natural mineral applications, to enhance soil physical characteristics, using cover crops and mulch to enrich SOM content. We assessed chemical soil properties such as total organic carbon (TOC), labile-C (permanganate oxidizable carbon [POXC], dissolved organic carbon [DOC], NaOH-soluble fulvic acids), glomalin content, and plant productivity. Our findings revealed that minimum-till had a significant time-dependent effect, increasing surface soil TOC by 17.58%, NaOH-soluble humic acids by 40.85%, and POXC by 77.75% over 3 years. Mulch and cover crop treatments enhanced specific carbon parameters and crop production. Different methods of assessing carbon levels proved useful for tracking time-dependent changes in soil quality. Labile-C forms such as DOC and POXC were most effective for shorter experiments, while TOC, glomalin, and NaF-soluble humic acids were better indicators for more extended experiments. These findings provide valuable insights for sustainable soil management practices.