Minimal soil disturbance and increased residue retention on aggregates carbon storage potential and energy relations in Typic Ustochrept soil of Uttar Pradesh: A review

Abstract

The conservation treatments were found to significantly improve soil health. The review paper revealed that, all the conservation tillage systems recorded significantly higher soil organic carbon at 0-15 cm depth and 15-30 cm depth higher soil carbon sequestration over conventional systems. However, biological soil quality such as soil microbial biomass carbon and nitrogen were significantly higher in all the tillage systems except conventional tillage without crop residue. Irrespective of the treatments, micro-aggregates were found to be poorer in carbon content, but richer in their capacity to retain it by way of larger activation energies. In surface soil (0–15 cm), the maximum proportion of total aggregated carbon was retained with 0.25–0.106 mm aggregates, and conservation tillage had the greatest ability to hold the organic carbon. However, different forms occurred at higher levels in the 15–30 cm soil layer under the conventional tillage. Compared to conventional tillage, macro-aggregates in conservation tillage was increased by 50.13% and micro-aggregates of the later decreased by 10.1% in surface soil. 50% surface residue retention caused a significant increment of 15.65% in total aggregates in surface soil (0–5cm) and 7.53% in sub-surface soil (5–10 cm). In surface soil, the maximum (19.2%) and minimum (8.9%) proportion of total aggregated carbon was retained with >2mm and 0.1–0.05 mm size fractions, respectively. Conservation agriculture practices secure good soil health by improving soil aggregation (53.8%) and increased energy output with respect to the conventional tillage.