In order to monitor tree woody increment and measure plant growth yield, metal dendrometer bands have been installed on a sub-sample of 2762 trees in 285 species within the 20-ha tropical rainforest dynamics plot in Xishuangbanna. The equipment is aimed at better estimating diameter at breast height (DBH) of trees, so as to provide data for studies on tropical rainforest and biodiversity monitoring.

   The equipment installation was trained by Dr. Shirley Xiaobi Dong from Harvard University.

   The dendrometer bands wrap like a belt around a tree at breast height. A spring secures the ends and two measuring points are punched where the band overlaps. An initial diameter at breast height is recorded for each tree. As the tree grows, the spring stretches, and the measuring points are pulled apart. By measuring this increasing distance between points, we can accurately determine the increase in the tree’s diameter.

   The trees in 5cm<DBH<255cm are chosen to be equipped with dendrometer bands, among which almost all trees with DBH>80cm are included. A systematic census is planned to be carried out every quarter. Changes of the biomass of trees will be recorded.