Exergoenvironmental damages assessment in a desert-based agricultural system: A case study of date production

Abstract

Developing countries, especially those in hot and dry areas, need more attention to achieve sustainable development as they apply excessive inputs in production processes. The present study aims to quantify the amount of environmental emissions and determine the most appropriate pattern of energy use in the date (Phoenix dactylifera L.) production process using thermodynamic analysis. The information was gathered through questionnaires and face-to-face interviews. From the results, cumulative exergy and energy demand for one Mg of date fruit production were calculated as 697 and 1640 MJ, respectively. Carbon dioxide emission was also measured at 197 kg Mg–1. Moreover, cumulative exergy consumption illustrated that manure and diesel fuel consumption is high, though diesel fuel and N consumption are given the most cumulative energy demand. Renewability indicator, cumulative degree of perfection, and the recoverable exergy ratio value of the date fruit production process were calculated as 0.62, 2.68, and 4.32, respectively. The date’s chemical exergy value was calculated to be 14.96 MJ kg–1. Dates have a high chemical exergy value because of their high carbohydrate content and low water content. As a result, crop chemical combinations have a direct impact on the production process. The total direct greenhouse gas emissions induced by the inputs consumption were 310.02 kg Mg–1. Emissions to air, soil, and water were 308.76, 5.60 × 10−1 and 6.96 × 10−1 kg Mg–1. In general, date production in Khuzestan province is partially renewable.