Assessing the capability of SDGs in achieving sustainable development from Nexus and global perspectives concerning water-food security

While SDGs have become a common ground to address global sustainability systematically, neither the existing synergies and tradeoffs among the different SDGs nor the magnitude of their compound effects at global versus national scales are well understood. Although introducing two indices of Spillover Index and Global Commons Stewardship (GCS) shed light on these issues, the capability of these widely agreed SDGs in fulfilling every nation's needs and dedication to protecting global sustainability is yet questionable. The SDGs' shortcomings are most evident when there are interdependencies and contradictory requirements among SDGs, becoming critical when SDGs at the national level protect one country at the expense of another one. The impact of achieving food security (often in water rich countries) through the import of agricultural products from their trade partner countries (often in water scarce countries) is one of the examples.

Here we aim to understand whether and how lacking a global nexus perspective that takes into account the synergies and tradeoffs among the different SDGs can counteract other nations and SDGs. We investigate the connection between SDG 2 and 6 in the context of water and food security; particularly, the impact of food security strategies of an importing country on the water security of its trade partner countries. The findings present that although neglecting the tight links between SDGs of 2 and 6 may have a positive sectoral effect at a country level, it fails global sustainability as it impacts the involved countries unevenly and often antipodally. it emphasizes the need for a revision of SDG2, as it inadequately captures the perspective of food security from the standpoint of hunger. This study advocates for inclusion of  NEXUS and system thinking in the reformulation of the SDGs, their targets, and the associated indicators.