Life cycle assessment of Camellia (Camellia oleifera spp.) seed oil production in China for forestry sustainability and food security

Abstract

As China advances its National Woody Oilseed Strategy (2021–2035) to enhance edible oil self-sufficiency, reconciling camellia oil production with carbon neutrality goals demands precise emission diagnostics. In this study, a new forest-to-oil module was developed, utilizing operational data from 37 forest farms and processing plants in China. In accordance with the GHG Protocol Corporate Standard (Scope 1, 2 & 3), the LCA system for camellia oil spans from the nursery gate to the oil-mill gate, covering all direct (Scope 1), indirect energy (Scope 2) and upstream value-chain (Scope 3) greenhouse gas (GHG) emissions (assessed with global warming potential, GWP) associated with both forest farm operations and oil mill processes. Results show a carbon intensity of 3.91 t CO₂-eq per ton oil, translating to annual sectoral emissions of 7.81 Mt CO₂-eq based on China’s 2025 camellia oil output (2.00 million tons). Organic fertilizer (45.27% of total) and compound fertilizers (29.91% of total) dominate emission sources. Spatial analysis identifies three critical provinces—Hunan (29.46%), Jiangxi (22.43%), and Guangxi (12.83%)—collectively responsible for 64.72% of national production emissions, the disparity stems from regional grid emissions and interprovincial transport distance variations. Scenario modeling demonstrates 4.16–14.57% emission reduction potential through: (1) precision fertilization targeting 25%–30% nitrogen efficiency improvement, (2) renewable energy integration in processing (40% solar/wind penetration), and (3) intermodal logistics optimization. These findings provide spatially explicit mitigation pathways, emphasizing the necessity of province-specific policies balancing oil security and decarbonization targets. These insights not only guide forestry units in lowering their greenhouse gas emissions but also highlight the importance of sustainability in the camellia oil industry, offering essential support for its enhancement.