WOODY SPECIES WITH HIGH WOOD DENSITY ARE MORE VULNERABLE TO GLOBAL CHANGE IN SOUTH CHINA

Abstract

Background: To cope with global change, plants shift their distributions. Rare species tend to shift their distribution more. Over 30% of the land is covered with woody species, which because of their longevity offer unique opportunities to monitor distribution shifts. The study addresses the following questions (1) how the distribution range of eight rare woody species is changing and how effectively the plants cope with the shift; (2) whether plant traits could predict those parameters. Maxent Distribution Modelling, was carried out for this purpose, on species observation records prior to 1980 under present climatic conditions and four future (CMIP5) scenarios. To assess how effectively plants cope with migration species observations after 1980 were assessed. Relationships with plant trait data on three traits were finally assessed.

Results: The distribution ranges for four out of the eight species expanded northwards. Temperature driven (mostly through mean annual temperature which was ranked first for six out of the eight species) rather than precipitation (mean annual precipitation was ranked first only in two cases and in one case precipitation of the driest month was ranked third) driven variables described distribution shifts best. Wood density summarized well the susceptibility of those plants to climate change. There are many woody species in tropical and subtropical areas for which we have very little information available.

Conclusion: Subject to the small pool of species, a plant trait was identified, wood density, that could summarize responses to global change that could potentially be used as a tool in conservation ecology to prioritize conservation efforts.