Abstract

Energy flow is an important criterion in assessment of sustainability in agroecosystems, as higher energy use efficiency and a better balance between energy inputs and outputs being desirable. In this study, energy input, energy output and energetic indices in tea agroecosystems located in Lahijan, Guilan province of Iran were evaluated in 2014–15 crop year. The results revealed that energy input and output in tea agroecosystems were 23113 and 9056 MJ/ha, respectively. Nitrogen fertilizer and manure were the most intensive inputs with 48.6 and 13.9% share in the total energy input, respectively. Energy efficiency and energy productivity in these agroecosystems were estimated as 0.25 and 0.49. The non-renewable energy sources had a contribution of 77.5% of the total energy used in tea farms. Our results showed that energy was not used efficiently in tea farms in this region. Improvement of agronomic management, especially nitrogen management, can notably improve the energy balance, thus; overall sustainability in these agroecosystems.