We are doing science for policy
The Joint Research Centre (JRC) is the European Commission's science and knowledge service which employs scientists to carry out research in order to provide independent scientific advice and support to EU policy.
A recent JRC-led article quantifies the water footprints of different types of nut production, and discusses options for water-sustainable nut production.
It finds that 74% of irrigated (as opposed to rainfed) nuts are produced under water stress.
Nuts are a great source of nutrients and protein.
They contain mainly unsaturated fatty acids, fibre, vitamins, minerals, antioxidants and phytosterols. Groundnuts (peanuts) contain about 257g/kg of protein, while the protein content of treenuts ranges from 18g/kg (chestnuts) to 200 g/kg (almonds).
They are therefore recommended as a healthy food group by many dietary guidelines, including the recent EAT-Lancet reference diet, which could lead to a substantial increase in future global nut production.
However, nuts require large amounts of water to produce.
In a new publication in Global Food Security, scientists from the JRC, the University of Twente and the University of Nebraska quantify the amount of global irrigated nut production under water stress.
They find that 74% of irrigated nuts are produced under water stress (of which 63% are under severe water stress), throughout many regions of the world, most notably in India, China, Pakistan, the Middle East, the Mediterranean region and the USA.
Groundnuts account for the largest quantity (8.7 million tons per year) produced under water stress, with hotspots in China and India.
Of the treenuts, almonds account for the largest quantity (1 million tons per year) produced under water stress, of which 60% are produced in California, followed by walnuts (0.67 tons per year), pistachios (0.36 tons per year) and hazelnuts (0.28 tons per year).
In the Mediterranean basin, large amounts of almonds and hazelnuts are produced under water stress, including in Spain, Italy, Greece, Turkey, Israel, Lebanon, Libya, Tunisia and Morocco.
The authors calculate that, if the global population in 2050 were to adhere to the recommendations of the EAT-Lancet reference diet, global treenut production would have to increase more than 11-fold, and groundnut production almost 7-fold.
As many nuts are already being produced under water stress, such an increase in production should be done in a water-sustainable way.
The authors identify 5 considerations to address in order to ensure water-sustainable nut production:
Such considerations could help reach Sustainable Development Goal (SDG) 2 – Zero Hunger (End hunger, achieve food security and improved nutrition and promote sustainable agriculture), in harmony with SDG 6 - Clean Water and Sanitation (Ensure availability and sustainable management of water and sanitation for all).