Evaluation of Current Freshwater Requirement in Asia Based on Global Food Trade and Food Supply-Demand Balances

Abstract

This study aims to evaluate the current freshwater requirement in Asia based on global food trade balance and food supply-demand balance matrices. The concept of a water footprint was adopted to estimate both supply and demand side freshwater requirements along with water transportation resulting from food import and export. Rain-fed (green water) and irrigation (blue water) consumption were considered. For blue water, irrigation efficiency was also considered to convert water consumption into water withdrawal because the former did not include irrigation water losses resulting from irrigation technology and management systems. It was concluded that as Eastern Asia mainly imports oil crops and oils (190 km³), cereals (69 km³), and meats and eggs (59km³), it is Asia’s largest importer of imported freshwater volume, with a total volume of 397km³, mainly from Asia (117km³), North America (129km³), and South America (94km³). In contrast, South-Eastern Asia is the largest exporting area in Asia, exporting predominantly oil crops and oils (180km³), rice (105km³), and beverages (53km³) with a total exported freshwater volume of 421km³. Moreover, an additional analysis of palm oil in Malaysia and Indonesia was implemented to show the utility of our simulation data.