[Photosynthetic characteristics of Emmenopterys henryi seedlings and their relationships with environmental factors].
摘要
, net photosynthetic rate of E. henryi seedlings showed singlet diurnal variation in undercanopy and crown edge, and showed a bimodal pattern in forest gap and forest edge. Seedlings were shade-tolerant plants with the low shade-tolerant ability. The order of light saturation point, light compensation point, and dark respiration of their functional leaves in different habitats was the same as follows: forest edge ＞ forest gap ＞ crown edge ＞ undercanopy, and the order was inverse when sequenced by apparent quantum efficiency. Seedlings were highly adaptable to forest gap and crown edge, with higher transpiration rate, stomatal conductance, water use efficiency (WUE), and net photosynthetic rate. Seedlings in forest gap had lower leaf chlorophyll content, but they grew fast and therefore showed the maximum biomass. Net photosynthetic rate of the seedlings showed significant positive correlation with PAR and stomatal conductance. For undercanopy, seedling photosynthesis was facilitated by reducing canopy density and increasing light transmittance. For forest edge, vegetation cover should be increased with reducing light intensity to ensure rapid growth of the seedlings.