Morphological and Physiological Responses of Acer mono and Quercus liaotungensis Seedlings to a Forest Light Gradient
To investigate the acclimation of Mono Maple (Acer mono) and East-liaoning Oak (Quercus liaotungensis) seedlings under the forest light gradient and the relationship of the acclimation to seedling banks in the oak forests,two-week-old seedlings of these two species were assigned to four various radiance levels:100％,51％,22％,and 12.8％ of natural light in the forest environment.We measured their survival,photosynthesis,photosynthetic pigment content,growth,root morphology and biomass accumulation and allocation after one growing season to provide evidences for dynamics of understory seedling bank and succession of temperate oak forests.The results showed that the survival of Mono Maple and East-liaoning Oak seedlings was similar after germination.However,Mono Mample seedlings had smaller maximum photosynthetic capacity,light saturation point and pigment content than that of East-liaoning Oak seedlings,but higher seedling height,total root length,secondary root length,root surface area and biomass accumulations of all organs.Mono Maple seedlings invested more biomass to foliage while East-liaoning Oak seedlings invested more biomass to underground.At 22％ and 12.8％ relative transmittance levels,survival of Mono Maple seedlings decreased significantly compared with those growing under 100％ transmittance level.Under the lower radiation regimes,survival of East-liaoning Oak seedlings increased.However,there was similar survival of two seedlings under 12.8％ transmittance condition.When growing under shades,mono maple seedlings lowered light compensation point and dark respiration rate and increased chlorophyll contents significantly,and they had relatively greater physiological responses and but relatively smaller morphological responses,such as biomass accumulation and allocation,than East-liaoning Oak seedlings.
Acer monoQuercus liaotungensislight responselight acclimationseedlingssurvival and growth strategies
国家科技期刊平台
NSTL
万方数据
维普
