Impact of Tephrosia candida alley cropping on soil fertility in Ranchi district of Jharkhand

Abstract

A field trial was conducted at the Agroforestry Research Field, Faculty of Forestry, BAU, Ranchi, under a subtropical humid climate in Northeast India during 2023-2024 to assess the physico-chemical properties of soil in alley cropping and sole cropping systems at two depths (0-15 cm and 15-30 cm). The study involved four-year-old hedgerows of Tephrosia candida (Hoary Pea) intercropped with arable crops (during both Kharif and Rabi seasons) in a Randomized Block Design with four replications and ten treatments, viz., T1 (T. candida + Soybean/Linseed), T2 (T. candida + Finger millet/Field pea), T3 (T. candida + Peanut/Lentil), T4 (T. candida + Black gram/Mustard), T5 (T. candida + Sesame/Chickpea), and sole cropping without hedgerows: T6 (Soybean/Linseed), T7 (Finger millet/Field pea), T8 (Peanut/Lentil), T9 (Black gram/Mustard), and T10 (Sesame/Chickpea).The results revealed that soil under T. candida-based alley cropping exhibited a considerable increase in pH across all treatments at both depths. Electrical conductivity also showed an improving trend under intercropping. Soil Organic Carbon (OC,%) significantly improved in alley cropping compared to sole cropping at both depths. A marked increase in the availability of nitrogen, phosphorus, and potassium was recorded in the soil across all treatments under alley cropping, particularly within the 0-15 cm soil depth. However, a consistent decline in the availability of essential nutrients (N, P, K, and OC) was observed in the subsoil layer (15-30 cm) under both alley and sole cropping systems. In contrast, soil pH exhibited a progressive increase with depth, indicating depth-dependent variation in soil chemical properties. The study clearly indicates that T. candida-based alley cropping serves as an effective and sustainable agroecological strategy for maintaining and improving soil health over extended periods.