Professor Sharif on the future of agricultural irrigation
Professor Adel Sharif, Director of the Centre for Osmosis Research and Applications at University of
Surrey talks about how his research is helping to address world decline in fresh water sources.
Water is not just the essential ingredient for life, but also a fundamental factor in the economy of any country. Water has also a significant effect in the geopolitics around the world. While more than 70% of the earth’s surface is covered with water, only 0.1% of that is suitable for human use in streams, rivers and lakes; 97% is too salty in seas and oceans; 0.8% is underground and the remaining 2.1% is trapped in the ice caps. Of the 0.1% of fresh water, which is not evenly distributed, only 30% is accessible, with the rest running off to the seas. This means that only 0.03% of the water on earth is in use.
Fresh water sources are in continuous decline due to rapidly increased consumption as a result of population growth, expansion of irrigated agriculture, rising standards of living, industrial developments, climate change, global drying and salt rising. Water shortages affect 88 countries that are home to half the world’s population. The availability of fresh water is likely to drastically decrease unless improvements to the current desalination. This is also a critical problem for agriculture, where seawater is too salty for almost all forms of crops. Farming itself accounts for 70% of water use.
Based on ongoing research at the Centre for Osmosis Research and Applications at the University of Surrey, a new approach is being developed which provides a practical, low-cost option for making use of seawater in agriculture, thereby reducing the pressure on drinking water stocks and allowing previously arid regions to be used for producing food.
The accessibility of the technology means no need for investment in genetically modified crops or ongoing treatments for the soil. The solution, which makes seawater irrigation on a large scale a realistic and sustainable solution to food supply problems, does not require high pressure pumps or expensive distillation units. Instead, the new approach makes use of the natural process of evaporation alongside a membrane designed to retain the impurities in the water, including the salts, allowing only pure water to reach the plants.
The project has built on our work on Manipulated Osmosis Desalination (MOD) which is currently used in Gibraltar and Oman to produce drinking water for human consumption - and recently won the Queen’s Anniversary Prize for outstanding achievements in higher education. The MOD is currently the leading technology for desalination, reducing energy use by up to 30 per cent compared to conventional plants, reducing chemical consumption and carbon footprint.