Energy flow modeling and economic analysis of olive production based on different orchard size in Guilan province of Iran

ABSTRACT: This research was carried out on use of energy inputs and economic analysis of olive production under three main orchard sizes in Rudbar area of Guilan province, the origin of olive plant in Iran. Data were collected from 83 gardeners by face to face questionnaire method. The research result revealed that average yield was 1.8 ton ha-1 and total energy consumed in olive production calculated as 20.6 GJ ha-1. The share of energy forms were 42.37%, 57.63%, 12.82 and 87.18% for direct, indirect, renewable and non-renewable energies respectively. The energy productivity was calculated as 0.06 kg MJ-1, 0.12 kg MJ-1 and 0.14 kg MJ-1 for small, medium and large orchards respectively. Cobb-Douglas production function was used to determine a relation between energy inputs and yield. Sensitivity analysis presented among the energy inputs chemical biocides had the highest impact on yield followed by human labor and farmyard manure. The economic analysis indicated that benefit to cost ratio were 1.40, 1.44 and 1.52 for small, medium and large size of orchards respectively. Although the large orchards (bigger than 15 ha) had best management in energy usage and highest benefit to cost ratio, but they had high consumption rate of chemical fertilizers and biocides to product maximum level of olive yield and it is not go along sustainable agriculture. In order to exclusion of environmental pollution, management of inputs usage need to improved in small, medium and large olive orchards, so that the yield changes could be explainable.