Forest characteristics and population structure of Glyptostrobus pensilis, a globally endangered relict species of southeastern China

The Chinese water pine Glyptostrobus pensilis is the sole surviving species of the genus Glyptostrobus. It is endemic to southern China, central Vietnam, and eastern Laos, and today it is nearly extinct in the wild. Forest community characteristics and population structure of G. pensilis in China have remained un-known up to now. We investigated six swamp forest stands and analyzed their forest community characteristics (i.e. vertical stratification, species composition, and diversity) and population structure, including the frequency distribution of DBH (diameter at breast height) and age-classes as found in Fujian Province, southeastern China. The vertical stratifications of all the forest stands were rather simple. The remaining wild specimens ranged from roughly 15 to some 357 years for an average of ca. 85 years, with only a few individuals less than 20 years old. Compared with the stands and populations of G. pensilis in Vietnam, the taxonomic compositions of the stands in the two regions were different, except for the dominant species-G. pensilis. The Shannon-Wiener index showed the overstory of each stand had much lower diversity (0.26 on average) in Fujian Province than that (1.97 on average) in Vietnam, whereas the diversity indices were about the same (around 2.41) for the understories in the two regions. Furthermore, we discovered 18 G. pensilis seedlings at the study sites in Fujian Province. This discovery demonstrates that G. pensilis regeneration is extremely poor and its populations are declining, although these populations are rela-tively healthier than those in Vietnam.

Forest Structure and a Sustainable Management Solution at the Permanent Plot in Bidoup-Nui Ba National Park

Vietnam is one of the countries with high biological diversity in the world but also greatly influenced by climate change.Therefore,it is necessary to have a solution for sustainable forest management through field surveys in permanent plots to study forest ecology,combining advanced GIS(Geographic Information System)technologies such as Google Earth,Global Mapper,etc.to monitor changes in forest structure and dynamics.The paper is based on the inheritance of the first measurement data in 2012 and directly measures in the second time after 5 years in 2017 at a 10-ha plot with ten 1-ha subplots.The results show that the number of trees is the highest at the diameter class of 10-20 cm(<20 cm),accounting for about 60%of the total number of trees of each 1-ha sub-plot and the study site and at the height of<20 m,respectively 8,402 out of 10,261 in 2012 and 8,189 out of 10,013 in 2017 were measured.In addition,the result of this paper indicates that Google Earth software is one of the most effective GIS tools in planning biodiversity conservation strategies and natural resource management.