Aggregate breakdown of two texturally different soils under different land-uses in semiarid tropical environments

The aggregate breakdown phenomenon under a land-use differs with changes in rainfall characteristics and aggregate size. Therefore, an attempt has been made through the present study to evaluate the aggregate breakdown dynamics using 4land-uses, 4-aggregate size classes, and 3-moisture contents following a completely Randomized Block Design using a simulated single raindrop technique. The natural aggregates were collected from two texturally different soils that is, sandy loam and loamy sand at DR Bhumbla Zonal Research Station for Kandi Area, Ballowal-Saunkhri, district SBS Nagar, Punjab. These different sized aggregates were exposed to simulated single raindrops of size 2.5, 3.5, and 4.5 mm respectively. Each sized aggregate breakdown by a single raindrop technique under a land-use follows the order: fallow>arable>forests>grasses. The kinetic energy of raindrop at impact was higher under land-use grasses at air-dry moisture content and minimum under land-use fallow at saturated moisture content in both types of soils. The interactive effect of land-use and aggregate size was significant in breakdown of the aggregate at known moisture content by a single raindrop technique. Further studies are needed to quantify the potential effects of plant root systems in breakdown of aggregate under a land-use.