Impact of forest product manufacturers on forestland attributes across South Carolina, United States

• Identifies the hotspots of the forest industries and carbon, volume, and harvest removals. • Used a mixed-effects modeling approach to quantify the effects of forest industries. • Observed the harvest volume increment and shift temporally. • Increased effect of biomass industries on harvest volume observed between the two periods. Intensive resource consumption and competition change the spatial distribution of forest product manufacturers (FPM). While raw material utilization is crucial for economic growth, intensive consumption often conflicts with the carbon stock levels of forests. Moreover, expanding harvesting rates driven by concentrated resource extraction may have a disproportionate impact on forestland attributes. This study assessed the decadal, 2011-2021, change in the spatial distribution of four types of primary FPMs and quantified the effect on the forestland attributes such as trees, volume, removals, and aboveground carbon across three ecoregions of South Carolina. Kernel density analysis identified two clusters of FPMs across South Carolina, one overlapping the Piedmont and Southern Plains and another overlapping the Southern Plains and Coastal Plains, with the latter migrating towards the urban areas of the Coastal Plains. The total production capacity of biomass FPMs increased by 822 metric tons, with the Piedmont region experiencing the most significant growth between the years. Meanwhile, the production capacity of the pulp & paper industry decreased by 641 metric tons between 2011 and 2021. Conversely, the overall production capacity of other FPM industries has shifted across the ecological regions of South Carolina. As expected, northwestern counties in the Piedmont region were identified as hotspots for aboveground carbon (AGC). Interestingly, hotspots of harvest volume (HV) shifted from counties in the Coastal Plains to the Piedmont region, suggesting an increase in harvesting intensity with the growth of FPM capacity. Our mixed model observed increased effects of biomass mills on HV (estimate = 0.32; confidence interval = [0.1, 0.55]). Additionally, live tree density declined by more than 10% despite an increase in merchantable volume (MV) across the state, indicating the aging of wood and lower recruitment in the region. Newer FPMs around high MV areas will minimize transportation costs, while the establishment of FPMs may limit the co-benefits of carbon markets in areas with high AGB. Given the uncertainty over the carbon and climate policies, landowners may prioritize forest harvesting for higher-bidding mills over carbon sequestration in the future. Moreover, the purchasing power of mills should be analyzed, given the evolving dynamics of harvesting patterns across the Piedmont.