Abstract This study was conducted in order to determine energy consumption, model and analyze
the input–output, energy efficiencies and GHG emissions for watermelon production using artificial
neural networks (ANNs) in the Guilan province of Iran, based on three different farm sizes. For this
purpose, the initial data was collected from 120 watermelon producers in Langroud and Chaf region,
two small cities in the Guilan province. The results indicated that total average energy input for
watermelon production was 40228.98 MJ ha–1. Also, chemical fertilizers (with 76.49%) were the
highest energy inputs for watermelon production. Moreover, the share of non-renewable energy
(with 96.24%) was more than renewable energy (with 3.76%) in watermelon production. The rate
of energy use efficiency, energy productivity and net energy was calculated as 1.29, 0.68 kg MJ1
and 11733.64 MJ ha1, respectively. With respect to GHG analysis, the average of total GHG
emissions was calculated about 1015 kgCO2eq. ha1
. The results illustrated that share of nitrogen
(with 54.23%) was the highest in GHG emissions for watermelon production, followed by diesel fuel
(with 16.73%) and electricity (with 15.45%). In this study, Levenberg–Marquardt learning Algorithm
was used for training ANNs based on data collected from watermelon producers. The
ANN model with 11–10–2 structure was the best one for predicting the watermelon yield and
GHG emissions. In the best topology, the coefficient of determination (R2) was calculated as
0.969 and 0.995 for yield and GHG emissions of watermelon production, respectively. Furthermore,