Comparative environmental analysis of sugar beet production using a solar-driven robot and conventional systems from a sustainability perspective

In the context of rapid global population growth and climate change, balancing agricultural productivity with environmental sustainability has never been more important. Precision farming technologies, including robotics, are touted as having huge potential to increase farm productivity, reduce energy and resource use and compact soil, while reducing the overall environmental impact of on-farm production. This comprehensive study presents, for the first time, a detailed analysis and environmental benchmarking of two organic sugar beet production (SBP) systems, conventional (CONV) and robotic (RBT), based on field experiments in Lithuanian conditions where a solar-powered robot is integrated into the production system to carry out sowing and weeding operations. In order to reduce the potential environmental impact and to understand the consequences of using the robot in agriculture, a Life Cycle Assessment (LCA) of the entire SBP process up to the factory gate was carried out. The results of the analysis show that the conventional system has higher total GHG emissions than the robotic system, 36.98 and 27.18 kg CO2eq t-1, respectively, with poultry manure being the largest contributor. The higher beet yield in the RBT system, mainly due to effective weed control, resulted in a higher GHG emissions ratio (14.72) and a higher sustainability index (13.72). The LCA results showed that the CONV system had a higher negative environmental impact than the RBT in all eleven environmental impact categories assessed, with the most pronounced difference in the Ozone Depletion (OD) category. Diesel fuel was identified as the most important environmental factor for organically growing sugar beet in all considered impact categories, with the most notable environmental impact (about 94%) in the terrestrial ecotoxicity category in both systems. Normalization of the results showed that marine aquatic ecotoxicity (ME) had the greatest (78%) influence of all exposure categories for both cultivation systems, CONV - 22079.82, and RBT 18121.61 kg 1.4-DBeq per ton of produced sugar beet. The study found that increasing yields and reducing fossil fuel use in organic farming are the two most promising strategies for achieving sustainability and efficiency in food production.