Xibei zhiwu xuebao (Apr 2024)
Effects of tree species composition on species diversity of different plantation communities in Chengdu ring expressway
Abstract
Abstract [Objective] The study aims to explore the effects of tree species composition and other stand factors on species diversity of plantation communities in different road areas, and provide reference for the construction and management of plantation communities in Chengdu. [Methods] By using the typical plot method, the stand factors and understory vegetation species diversity of 5 different tree species in the plantation community (Ⅰ, poplar pure forest. Ⅱ, camphor and poplar mixed forest. Ⅲ, pure camphor forest. Ⅳ, mixed forest of camphor and eucalyptus. Ⅴ, eucalyptus grandis forest) of Chengdu Ring Expressway were investigated. [Results] (1) A total of 190 species of understory plants belonging to 71 families and 131 genera were recorded in the study area. The number of species of plant families recorded under the forest was more in the herbaceous layer than in the shrub layer, among which the number of understory species recorded in the pure camphor forest was the highest. (2) The important values of Broussonetia papyrifera and Humulus scandens dominated the shrub layer and herb layer of different plantation communities, respectively. (3) The shrub species richness index (D ) of pure camphor forest was significantly higher than that of the other communities (P Ⅳ > Ⅰ > Ⅱ > Ⅴ, of which H of pure camphor forest was significantly higher than that of the other communities, except mixed forest of camphor and eucalyptus (P <0.05). (4) The average crown width in the tree layer was significantly positively correlated with D index and H index in shrub layer, H index, H' index, D index, and Pielou uniformity index (Jsw) in herbaceous layer (P <0.01), and negatively correlated with H' index and Jsw index in shrub layer (P <0.01). The average height under branches in the tree layer was significantly positively correlated with H index, H' index, D index, and Jsw index in shrub layer (P <0.01). [Conclusion] The tree species composition, average undershoot height, and average crown width of the tree layer significantly affect the species diversity of plantation communities in the road area, and the selection of appropriate tree species and regular pruning management would be conducive to the formation of good tree and shrub community structure and the maintenance of understory vegetation species diversity in road plantations.
Keywords
