Traders in Food Systems are Keystone Actors for Water Stewardship

Unaltered biosphere is the main mankind ally in mitigating climate changes. Biosphere stewardship indicates traders, identified as Transnational Corporations (TNCs), as a keystone actor of the global Production Ecosystem and a major driver of the outsized impact on the biosphere. Yet, despite water is the blood of the biosphere, efforts to analyse the role of TNCs in reallocating global water resources have been poor. Capitalizing on the high-resolution data by the Trase initiative and by focusing on the paradigmatic case of the Brazilian soy, we found that major soy traders displace on average twice as much virtual water as top-importing countries- except for China. Bunge virtual water export in 2018 reached 15 Gm³, almost twice the export of Thailand (7.8 Gm³)  and that of Louis Dreyfus more than twice the one of Netherlands (4.6 Gm³). Results also show that companies face local water risk through the exposure to drought (30-45% probability of occurrence), which can disrupt along the whole supply-chain. Countries, which have been considered as far the main player to achieve sustainable supply chains, are strongly tied to companies and thus are not able to properly act without joint efforts with traders. In strong analogy with the ocean stewardship we argue that TNCs should be recognized as Keystone Actors for water resources conservation and should cooperate with science, local authorities and communities to assure the integrity of water reserves and the hydrological cycle, global commons of the biosphere.