Impact of Different Land Use Practices on Size of Soil Aggregates and Its Mean Weight Diameter under Vertisols of Central India

The present study was carried out at JNKVV, Jabalpur (23010’ N latitude, 79057’ E longitudes and at elevation 393.0 meters above mean sea level). This study was carried out in 2019 that laid out in split plot design with nine main treatments of land use practices (forest land, perennial forage land, uncultivated land, aonla orchard, rice-wheat system, soybean-wheat system, guava orchard, mango orchard and citrus orchard) and three sub-plot treatments of soil depths (0-20, 20-40 and 40-60 cm) which were replicated three times. A total of 81 soil samples were subjected to determination of different size (> 5.0, 2.0-5.0, 1.0-2.0, 0.50-1.0, 0.25-0.50, 0.10-0.25 and <0.10 mm) water stable soil aggregates and mean weight diameter of soil aggregates. Results revealed that land use practices and soil depths significantly affect the mean weight diameter of soil aggregates, distribution of different size soil aggregates. It was noted that irrespective of soil depths, proportions of macro-aggregates (>0.50 mm size) and mean weight diameter were highest under forest land and lowest in soybean-wheat system. However, number of micro-aggregates (< 0.50 mm) increased with soil depths and macro-aggregates and mean weight diameter of soil aggregates were highest at 0-20 cm depth. It can be concluded that extent of soil disturbance significantly alters the proportion of macro-aggregates (>0.50 mm size) and mean weight diameter of water stable soil aggregates with higher in undisturbed (forest, uncultivated and perennial forage) land uses and lower in crop lands which decreased with increase in soil depths.