Focus on the use of water for food production.

 

Although global food production has kept pace with population growth, close to 750 million people (or 10% of the global population) were exposed to severe levels of food insecurity in 2019. Unfortunately, this number has increased even further over the course of 2020 due to the COVID-19 pandemic and its economic impacts worldwide.Rainfed agriculture covers 80% of the world’s cropland and accounts for the major part (60%) of food production. Rainfed agriculture has a global water footprint of5,173 km3 per year. Irrigated agriculture covers about 20% of cultivated lands, yet it accounts for 40% of food production, and has a global water footprint of 2,230 km3 per year. The global water footprint related to crop production in the period 1996–2005 was 7,404 km3 per year, representing 92% of humanity’s water footprint.

Despite striking economic growth in the past, there are still 2.1 billion poor people, of whom 767 million people live in extreme poverty. Of all people living in poverty, 80% live in rural areas, where agriculture continues to be the mainstay of their livelihoods. Estimates based on comprehensive national and subnational data indicate that 40% of actually irrigated area in the world is serviced by groundwater sources. With proper water accounting and the enforcement of strict withdrawal regulations, the adoption of highly efficient irrigation systems could reduce non-beneficial water consumption at the river basin level with more than 70% while maintaining the current level of crop yields, enabling the reallocation of water to other uses, including environmental restoration (Jägermeyr et al., 2015). The global economic value of the ecosystem services provided by wetlands only was estimated at US$26 trillion per year in 2011. However, much of the irrigation development worldwide that occurred in the last decades was considered a priority over environmental flows. The full nutrient recovery from wastewater would offset more than 13% of the global demand for these nutrients in agriculture. The recovery of these nutrients could result in a revenue generation of US$13.6 billion globally (Qadir et al., 2020). Beyond the economic gains ofreusing wastewater to maintain or improve agricultural productivity, there are critical human health and environmental benefits. The use of treated wastewater is becoming particularly appealing for agriculture in peri-urban and urban settings. It is estimated that 380 km3 of wastewater is produced annually across the world, which equals about 15% of agricultural water withdrawals. The irrigation potential of this volume of wastewater stands at 42 million ha. Globally around 14%, in terms of economic value, of the food produced is lost from postharvest up to, but not including, the retail level. Researchers found that the global production of lost and wasted food crops accounts for 24% of Total freshwater resources used in food crop production. Sustainable diets are those that are healthy, have a low environmental impact, are affordable and culturally acceptable. Such diets involve a limited consumption of meat, added sugars and highly processed foods, and eating a diversity of plant-based foods. Shifts towards sustainable diets could also reduce the use of water for food production by about 20% compared to current diets.