Horizontal and vertical variations in soil properties under different pruning regimes in Albizia procera based agroforestry system

Abstract

Trees' canopy pruning is one of the most important management strategies in agroforestry that allows understory crops to receive adequate sunlight for better growth and productivity. The effect of pruning on the productivity of intercrops is well known; however, information on its effect on soil properties is scanty. Hence, a study was conducted to determine whether canopy pruning has any effect on soil properties and what level of pruning should be adopted in agroforestry systems. The study was conducted in a 10-year-old Albizia procera (commonly known as white siris) based agroforestry system which included three factors: pruning level (0, 50, and 75%), sampling location (under and outside canopy), and soil depth (0–15 and 16–30 cm), replicated three times in a completely randomized block design. Canopy pruning, sampling location, and soil depth yielded varying effects on the studied soil parameters. The findings revealed that unpruned trees of A. procera caused maximum improvement in soil, followed by trees subjected to 50 and 75% crown pruning. Improvement under 75% pruning over 50% was not so prominent, implying that heavy pruning (75%) should be avoided to keep evapotranspiration under control. The study concludes that a moderate level of pruning (50%) is desirable in A. procera based agroforestry under semi-arid conditions for efficient use of above- and below-ground resources and improved soil health.