soil erosion risk mitigation and carbon sequestration potential of conservation agricultural practices in kandi region

Abstract

A study was carried out for two maize growing seasons in the kandi region of Jammu division to gauge and measure the influence of various conservation agricultural (CA) practices on seasonal runoff, soil erosion, soil carbon sequestration, aggregate stability and yield of maize. Three tillage variations i.e. conventional tillage (CA), minimum tillage (MT) and zero tillage (ZT) were employed, and were combined with management practices such as intercropping (i) with black gram, mulching (m) and residue retention (30%) (r). The total seasonal runoff during the year 2017 ranged between 1673 to 2264 m3/ha. The highest total runoff was recorded in treatment CT (2264 m3/ha) and the lowest total runoff was recorded in treatment ZTr (1673 m3/ha). During the year 2018 the total runoff values ranged between 630 to 851 m3/ha. Conventional tillage (CT) was at par with zero tillage and minimum tillage with respect to runoff. Runoff was significantly lowered with application of mulching, residue retention or intercropping. Sediment load varied widely among the different rainfall events as well as within the various treatments. Significant differences were observed among the different treatments for all the runoff causing events. Maximum sediment load was under conventional tillage (CT) and during many of the events it was closely followed by minimum tillage (MT). During the year 2017 the values of total seasonal soil erosion ranged from 2157 to 8013 kg ha-1, while in 2018 the values of total soil loss ranged from 710.9 to 3500.7 kg ha-1. It was clearly observed that maximum soil loss during both the seasons was observed in the conventional tillage (CT) treatment which was significantly higher than all other treatments. Both reduced tillage and soil cover could effectively reduce soil erosion. Organic carbon sequestration and aggregate stability were not significantly affected by CA practices, possibly because of the short nature of study. Grain yield of maize was significantly lowered in intercropping treatments. However, wh