Soil chemical properties under poplar-wheat agroforestry system in tarai lands of Uttarakhand

An investigation was carried out to study the chemical characteristics of soil under poplar-based agroforestry system at G.B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand during winter season of 2018. The poplar plants were about four and a half years old. Soil pH, soil electrical conductivity (EC), soil organic carbon (SOC) and contents of available macronutrients viz., N, P and K in surface soil (0–15 cm and 15–30 cm depth) were determined. Soil pH and EC were decreased whereas soil organic carbon, available nitrogen, phosphorous and potassium were higher under poplarbased agroforestry system as compared to open farming system. Highest nitrogen content was present under agroforestry system compared to open farming. At 0-15 cm the highest nitrogen measured was in treatment-1 plot (252.9 kg/ha) and lowest in treatment-8 plot (250.7 kg/ha). In open farming system the measured nitrogen content measured was 247.3 kg/ha. The maximum available phosphorus recorded was in treatment-2 plot (21.69 kg/ha) followed by treatment-4 plot (21.54 kg/ha). The agroforestry system recorded higher available potassium levels compared to the open farming system. Among the treatments, the treatment-5 plot showed the highest potassium content (219.6 kg/ha), followed by treatment-1 (219.3 kg/ha), while treatment-7 had the lowest (218.7 kg/ha); in contrast, the open farming system recorded 207.8 kg/ha. Therefore, the long-term adoption of poplar-based agroforestry system helps in improving the soil chemical properties as well as nutrient status.