Estimation of the soil and plant nutrient budget of the traditional Eucalyptus based agroforestry system in different spacing

Abstract

Traditional tree-integrated farming systems are adopted for the security of food, fodder and fuelwood. Therefore, investigations were carried out to study the leaf litter, wood litter, miscellaneous litter and total litterfall in Eucalyptus based agri-silvicultural system. It was further observed from the analysis of the data that leaf component was the main contributor to the total above-ground biomass in all the planting spacings followed by woody and miscellaneous. The major nutrient pool was in leaves, branches and miscellaneous matter types of litter. The total return of nutrients during both the years study period was in6×1.5 m spacing returned the highest amount of N (54.04 kg/ha) through leaf litter followed by 3×3 m spacing (53.05 kg/ha), 17×1×1 m spacing (52.85 kg/ha) in 2014-15. Out of which the total amount of these nutrients used by the intercrops was 44.01 (kg/ha) of nitrogen, 9.96 (kg/ha) phosphorus and 68.65 (kg/ha) of potassium. Hence the remaining amount 45.31 (kg/ha) of nitrogen and 7.05 (kg/ha) of phosphorus. Which was ultimately left unused in the soil during seven and eighth year of Eucalyptus planted at 3×3 m spacing the farmers can take barley as an intercrop with the Eucalypts terticornis with a  spacing of 3×3 m without adding any additional amount of nitrogen and phosphorus into the system. Hence can save some additional cost of fertilizer, which otherwise they have to add to raise intercrops with Eucalyptus.