Epiphytic lichens play important roles in many forest ecosystems. In different forest ecosystems, epiphytic lichens are influenced by various factors at different spatial scales. Previous studies have shown that host trees had an important influence on the on the distribution of epiphytic lichens in forests. However, the importance of non-dominant trees for lichen conservation is still unclear in many forest ecosystems.
Researchers from Xishuangbanna Tropical Botanical Garden (XTBG) conducted a study to determine the importance of overall tree species richness for conserving epiphytic lichens in Ailaoshan subtropical forests.
The researchers divided the tree species into dominant and non-dominant groups to reveal the effect of tree species difference on lichen diversity as much as possible at the local scale.
They observed that t both dominant and non-dominant trees were important in shaping the epiphytic lichen community in the subtropical Ailao Mountains, although the different tree groups supported distinct lichen species assemblages.
Dominant trees were not always more important than non-dominant trees for total lichen species richness, while non-dominant trees significantly influenced lichen species richness on all individual trees as well as across the two tree groups.
Dominant trees indeed influence lichen assemblages and tend to support more abundant lichen species. However, total lichen species richness was affected negatively by a higher number of dominant individuals in the four mono-dominant forests, possibly because they provided a higher number of homogeneous microhabitats for lichens.
The researchers thus concluded that not only dominant but also non-dominant tree species provide suitable habitats for epiphytes.
“Non-dominant trees cannot be ignored in forest conservation in the subtropical forests of southwest China”, said Dr. LI Su, first author of the study.