Environmental assessments of fast-growing plantations often begin with a deceptively simple assumption: that the plantation replaces an average cereal field. Yet, a realistic baseline is not a technical detail. It is part of the system being assessed. Whether willow, poplar or hybrid aspen replaces winter wheat, spring barley, temporary grassland or fallow land can substantially influence estimates of greenhouse-gas balances, soil carbon, nutrient losses, biodiversity effects and opportunity costs. For this reason, understanding where plantations are established, and what they replace, is essential for credible life-cycle assessment, land-use modelling and bioeconomy planning.
A 30-year assessment of fast-growing plantations in Sweden provides one of the most detailed empirical baselines currently available. The study traced the development of willow, poplar and hybrid aspen plantations between 1986 and 2017, combining plantation records, agricultural land-register data and spatial analysis. The results showed that willow remained the dominant system, but its area declined from approximately 14,000 ha around 2001 to 7,785 ha in 2017. Poplar and hybrid aspen partly offset this decline, reaching 1,738 ha and 676 ha, respectively, by 2017. In total, Sweden still maintained approximately 10,200 ha of fast-growing woody plantations, although their composition, location and agricultural context changed markedly over time. The full analysis is available here.
The results also showed that plantation establishment cannot be separated from changing policies and agricultural markets. Willow expansion was initially linked to Swedish policy support for energy crops, whereas its subsequent decline coincided with reduced incentives and rising cereal prices after 2007. Average cereal prices increased sharply relative to the 1990–2006 period, by approximately 49% for wheat, 40% for barley and 22% for oats. At the same time, many former willow plantations returned to cereal cultivation. However, new plantations were not established only on cereal land. In 2016, new willow plantations were commonly associated with former spring barley, winter wheat, temporary grassland and fallow land. Poplar plantations showed an even clearer association with lower-intensity agricultural land uses, particularly fallow land and temporary grass. These replacement patterns provide a practical basis for defining differentiated reference scenarios.
This distinction matters greatly for LCA. A plantation replacing intensively managed cereal land may generate different environmental trade-offs than one established on fallow land or temporary grassland, where fertiliser use, machinery inputs and baseline carbon dynamics are already lower. Treating all plantation establishment as a cereal-to-wood transition may therefore overestimate some environmental benefits or overlook relevant impacts. Rather than relying on a single generic counterfactual, future assessments could use a weighted portfolio of agricultural reference systems, reflecting the observed shares of cereals, grasses and fallow land replaced by each plantation type. Such an approach would make evaluations of short-rotation woody crops more spatially realistic, more transparent and more relevant for policy.
The study also illustrates that plantation systems are dynamic rather than uniform. Willow plantations increasingly concentrated in southern and more productive agricultural areas, whereas poplar tended to expand on less productive land. Smaller plantation units became more frequent, particularly those below one hectare, while large systems above ten hectares became relatively uncommon. These patterns reflect not only land availability, but also changing farmer preferences, local biomass markets, management choices and wider agricultural conditions. For researchers seeking robust baseline scenarios for plantations, the central message is clear: the environmental performance of a plantation cannot be assessed independently from the land-use trajectory that made it possible.
Further information: Research on biomass production, plantation forestry and land-use dynamics is available through the Biomass Production research group at the University of Eastern Finland. Further publications and activities can also be found at sites.uef.fi/biopro.
Reference
Xu, X., & Mola-Yudego, B. (2021). Where and when are plantations established? Land-use replacement patterns of fast-growing plantations on agricultural land. Biomass and Bioenergy, 144, Article 105921. https://doi.org/10.1016/j.biombioe.2020.105921
For related research, visit the Biomass Production research group, University of Eastern Finland.
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