| Popis: |
Increasing atmospheric carbon dioxide concentration, [CO2], has profound effects on growth and development of trees. Adoubling of [C02] generally stimulates photosynthesis (Murray 1995; Saxe, Ellsworth & Heath 1998) and can lead to a substantial increase in tree growth (Poorter 1993). For example, doubling [C02] increased the rate of photosynthesis per unit leaf area (A) of Pinus taeda by 14-146% (Ellsworth 1999; Liu & Teskey 1995; Thomas, Lewis & Strain 1994; Tissue et al. 1996; Tissue et al. 1997), and increased relative growth by 40-233% (DeLucia et al. 1999; Sionit et al. 1985; Thomas et al. 1994), we suggest that in very young seedlings, elevated [C02] effects may interact with internal factors such as seed N or C reserves. Thus internal and external factors that regulate growth atthe seedling stage may act acooectively to regulate subsequent seedling growth (Corbineau & Come 1995). |
Plný text