Life cycle impact assessment of a seaweed product obtained from Gracilaria edulis e A potent plant biostimulant

Increasing crop productivity for food security is a challenging task without compromising the environmental integrity. In this scenario, seaweed based plant biostimulants are one of the potential sources for sustainably improving crop productivity and mitigating climate change. However, in order to quantitatively express the environmental benefits it becomes imperative to estimate the impacts resulting from their production. Thus the present study was undertaken to determine the various impacts across nineteen environmental categories that resulted from production of 1000 L of Gracilaria seaweed extract-a potent plant biostimulant by using life cycle assessment methodology. The environmental impacts were apportioned between seaweed extract and downstream product (agar) on the basis of price allocation. Among the three different steps involved in production of the extract, the processing module contributed to higher proportion of impacts across different evaluated environmental impact categories and it ranged from 65 to 99% of the total impacts. Electricity requirement, shed and blowmoulding sub-processess within the processing step contributed to bulk of the evaluated environmental impact categories. Plastics used in packaging of the extract as well as those used in cultivation module contributed to more than 50% of impacts across 8 out of the 19 evaluated environmental impact categories. Thus, in order to render the product even more sustainable we would recommend the use of biodegradable products for making the raft as well as for packaging. In addition, marketing of the extract as a concentrate would further lower the environmental burden associated with the transport and packaging, thus rendering the SWE even more sustainable.