Decomposition of organic materials is one of the essential processes of material cycling in ecosystems, which can serve some important ecosystem functions. It is said that ca. 70% of variation in decomposition is generally governed by the three major components: environmental condition (e.g., temperature, moisture), material's quality (e.g., plant functional traits such as nutrients, secondary compounds), and decomposer community (e.g., microbes, soil fauna), and their roles or relative importance on decomposition have been discussed in many previous studies. Especially, the relationships between plant functional traits and decomposition have been intensively studied, and the variation in a set of functional traits were found to control the decomposition processes.
In this talk, first I will briefly overview the relationships between plant functional traits and leaf litter decomposition at a several scales in terrestrial ecosystems. Then, I will show how the successional stages or biomes shift the relationships between plant functional traits and leaf litter decomposition by comparing the relationships between young secondary and old-growth forests in temperate, seasonal dry tropical and aseasonal moist tropical regions. Finally, which environmental factors affect the variation in functional traits relating to the decomposition will be shown to discuss the response of decomposition to environmental changes.