Towards sustainable food production and climate change mitigation: an attributional life cycle assessment comparing industrial and basalt rock dust fertilisers

PurposeFood production is set to double by 2050 to feed the increasing world population. This poses a global challenge to minimise environmental impacts from intensified production and use of chemical fertilisers. The study investigates whether basalt rock dust fertiliser can be an environmentally sustainable close substitute to expensive conventional rock-derived P and K fertilisers.MethodThe study uses the attributional life cycle assessment method to estimate and compare 15 environmental impacts between basalt rock dust fertiliser, a potential source of phosphorus (P) and potassium (K), and five widely used industrial P and K fertilisers. In addition, we model hypothetical basalt substitution rates for PK fertilisers to highlight potential ecological savings in terms of carbon capture.ResultsBasalt rock dust fertiliser has minimal embodied environmental impacts across all 15 impact categories, including global warming, compared to industrial P and K fertilisers.ConclusionOur results suggest that transitioning to milled basalt as a natural geo-fertiliser to support food production may help address several UN Sustainable Development Goals such as 'Responsible consumption and production' and 'Climate Action and Zero Hunger'.