Carbon Footprint of Masson Pine (Pinus massoniana) Seedlings in Southern China: A Life Cycle Inventory and Sensitivities

Masson pine is a crucial species for afforestation and timber production in China; it plays an important role in mitigating global climate warming and increasing carbon sinks. Previous studies have primarily focused on the carbon sequestration potential and carbon storage of mature Masson pine plantations, while studies on the carbon footprint have received little attention. China produces hundreds of millions of seedlings annually, and estimating the carbon footprint of seedling production is crucial for assessing the carbon sink of forestry. By surveying existing Masson pine nursery operations for primary data in Guangxi, southern China, a new process-based life cycle inventory (LCI) dataset per 4 × 8 cm seedling was created, covering all stages from seed collection to the transportation of seedlings to retailers. Incorporating the new LCI data into the life cycle assessment (LCA) method, the total global warming (GW) impact of Masson pine seedlings was estimated to be 0.0232 kg CO2eq, equivalent to 0.873 kg CO2eq per gallon seeding. In this case, the total environmental impact of the Masson pine seedling was dominated by energy consumption (25.76%), chemical fertilizer production and N₂O emissions generated from its application (34.84%), and woven bag use in seedling dispatch (10.77%). Our results indicated that optimizing energy structures and implementing efficient water and nutrient management strategies could significantly reduce carbon emissions during seedling cultivation. This study highlights the potential for optimizing Masson pine production as a model for low-carbon forestry practices globally.