Establishment and two-year growth of a bio-energy plantation with fast-growing Populus trees in Flanders (Belgium): Effects of genotype and former land use

摘要

In April 2010, a large-scale Short Rotation Coppice (SRC) plantation was established with mainly poplar (Populus spp.) on a former agricultural site (cropland and pasture) in Flanders. The 12 selected genotypes planted were assessed on establishment and production characteristics during the first two years of growth and were found highly productive, with a volume index ranging between 1.00 (±0.68) and 1.93 (±0.97) dm~3 in growing season 1 (GS1) and between 2.75 (±1.70) and 11.91 (±6.33) dm~3 in growing season 2 (GS2). Despite high survival rates of the cuttings after planting, competitive weeds and management operations increased tree mortality during the growing season from 3.4 % up to 18.2 % averaged over the entire plantation. Weed control therefore turned out to be the key factor in the establishment success. Only a minor influence of former land use was observed during GS1, which is explained by the non-limiting nutrient conditions on both former cropland and pasture, and which disappeared during GS2. These productive soils also explained the high growth rates, with an average tree height of 247 cm and 445 cm and stem diameter (at 22 cm height) of 25.21 mm and 40.73 mm after GS1 and GS2, respectively. Genotypic and parentage variations were found to be less pronounced during GS1, and increased during GS2 as expected. The maximum leaf area index and total leaf area duration were shown to be good indicators of production and growth performance. The results of this paper confirm the high potential of SRC with poplar on agricultural land for bio-energy purposes.