Calfapietra Carlo, Gielen Birgit, Sabatti Maurizio, De Angelis Paolo, Miglietta Franco, Scarascia-Mugnozza Giuseppe, Ceulemans Reinhart
Università degli Studi della Tuscia, Department of Forest Environment and Resources (DISAFRI), Via S. Camillo de Lellis, I-01100 Viterbo, Italy.
University of Antwerpen, UIA, Department of Biology, Universiteitsplein 1, B-2610 Wilrijk, Belgium.
New Phytol. 2003 Nov;160(2):305-318. doi: 10.1046/j.1469-8137.2003.00899.x.
• In a free-air CO enrichment (FACE) study, above-ground growth of Populus alba, Populus nigra and Populus×euramericana was followed continuously during the first rotation cycle of a short rotation culture (SRC) plantation to test possible changes in the response to elevated CO occurring from planting until canopy closure. • Height, stem basal area, stem volume index, branch production, and bud phenology were monitored for 3 yr. Moreover the coefficient of variation and a competition index were calculated to analyse the onset and the typology of competition. • Volume index was higher under elevated CO by 77%, 24% and 22%, as mean value for the three species, in the first, second and third years, respectively. The stimulating response, although univocal, differed in extent among species. Branch production was stimulated only in the first year, whereas bud phenology was unaffected. • The analysis of these results show that growth was stimulated by elevated CO only in the first year, although differences in volume index remained significant even in the second and third years. In the third year, under canopy closure, only competitively advantaged individuals profited by the FACE treatment.
• 在一项自由空气CO₂浓度升高（FACE）研究中，在短轮伐期栽培（SRC）人工林的第一个轮伐周期内，持续跟踪了银白杨、黑杨和欧美杨的地上部分生长情况，以测试从种植到林冠郁闭期间对CO₂浓度升高的响应可能发生的变化。• 连续3年监测了树高、树干基部面积、树干体积指数、侧枝生长量和芽物候。此外，还计算了变异系数和竞争指数，以分析竞争的开始和类型。• 作为三年生树木平均值考虑，第一、第二和第三年中，CO₂浓度升高条件下的体积指数分别比对照高77%、24%和22%。CO₂浓度升高的促进作用虽无明显差异，但因树种而异。侧枝生长量仅在第一年受到促进，而芽物候不受影响。• 这些结果分析表明，CO₂浓度升高仅在第一年刺激了树木生长，尽管在第二年和第三年体积指数差异仍然显著。在第三年林冠郁闭时，只有具有竞争优势的个体从FACE处理中受益。
