Managing agricultural vulnerability to phosphorus scarcity through bottom-up assessment of regional-scale opportunities

Many developing countries are dependent on imported phosphorus (P) fertilizers and therefore increasingly vulnerable to scarcity of non-renewable global phosphate supplies, including short-term disruptions. A combination of participatory approach with quantitative substance flow analysis was used for identifying strategies for strengthening preparedness of regional food systems towards potential P scarcity. A P vulnerability index (PVI) - the lower its value, the higher the vulnerability (or P insecurity) - was defined on a regional scale in consultation with local stakeholders including government officials and experts and with farmers seriously affected by relevant policies and programmes. Potential mitigation and adaptation strategies were developed based on the estimated PVI and regional P flows. Regional policy planning and implementation with participatory approach are critical, because national, top-down policies may not cater to local and regional challenges and aspirations. The participatory approach offered fresh insights hitherto unidentified in top-down approaches. The study region, Sonipat in Haryana, India, is highly vulnerable to potential P scarcity (PVI of 38.68) but can theoretically reduce its P requirements by 11,574 t annually (about 85% of the current requirements) through recovery and recycling of P from human waste and by adjusting the fertilizer dose. Crop diversification combined with recycling and recovery of P and better governance can increase the PVI to 60 and above, implying adequate P security. Soil fertility, farmers' income, and access to institutional credit had the maximum impact on P vulnerability. The proposed framework can be applied in other countries to contextualize challenges related to P management and to devise strategies for building P security at regional scale.