Epiphytic lichens grow on branches and trunks of trees, sometimes with heavy cover, in many forest ecosystems. They are an important component in subtropical forests and contribute greatly to forest biodiversity and biomass. However, information on the biomass of epiphytic lichens is still deficient for many regions, e.g., the subtropics and the tropics. 

Researchers from Xishuangbanna Tropical Botanical Garden (XTBG) of the Chinese Academy of Sciences conducted a study to examine the vertical stratification pattern of epiphytic lichens associated coniferous forests in the subtropical forests in the Ailao Mountains in Yunnan Province, SW China.  

They present the first quantitative information on the vertical distribution of epiphytic lichen biomass in two primary and three secondary forests, on the basis of combined surveying of recent treefalls and standing trees. 

They found that lichen biomass was significantly influenced by forest type and host attributes. Although the primary forests conserve abundant lichen species, however, they have a lower biomass than secondary forests. 

They also found that tree species were unequally important as habitats for lichen colonization, and increasing tree diameter and height were associated with increased epiphyte biomass. The results indicate that the importance of tree attributes for lichen conservation is particularly noteworthy in forest practices. 

The distribution of epiphytic lichens was related to the environmental variations within, and among, forest types. Epiphytic lichens were non-uniformly distributed across forest type and tree species.

Moreover, their variable vertical distribution patterns appear to depend more on forest type and reflecting the different degrees of adaptation to light and humidity. 

The researchers thus emphasize the importance of epiphytes in subtropical forests, as well as sustainable forest management that integrates the conservation needs of lichens and their required ecological settings. 

The study entitled "Forest Type and Tree Characteristics Determine the Vertical Distribution of Epiphytic Lichen Biomass in Subtropical Forests" has been published in Forests.  

Epiphytic lichens in Ailaoshan subtropical forests. (Image by LI Su)