Fine root architecture, morphology, and biomass response to cutting in a Chinese cork oak (Quercus variabilis Blume) forest

摘要

This study aims to detect the variety of fine root growth with branch orders in response to forest cutting. The branching ratio (Rb), root morphological indices, and biomass of up to 3 branch orders of fine roots were investigated from 2 soil depths (0 cm to10 cm and10 cm to 20 cm) in Chinese cork oak (Quercus variabilis Blume) plots1and 3 years after forest cutting, compared with those of intact trees as the control. The number of fine roots was lower in the managed plots than in the control, particularly in the first-order roots. After1year of cutting, the proportion of the first-order roots decreased significantly, whereas the proportion of the second-order and third-order roots increased. Rb decreased significantly after forest management in the0-10 cm soil depth of plots after1year of cutting. The fine roots in the plots after cutting exhibited less root length density, lower specific root length, less surface area, and higher tissue density compared with those in control plots. The mean rootdiameter showed no significant change. The average biomass of the first 3 orders of roots in the plots1and 3 years after cutting was 72% and 83% of that of the control plot, respectively. The reduction of fine root growth was influenced mainly by the lack of photosynthesis in the managed forest.