Model simulation of isoprene emission flux in a tropical forest plantation of rubber trees

Continuous measurements on emission flux of isoprene were made by a fast isoprene system in a tropical forest in the middle of July 2002. Other parameters such as photosynthetically active radiation (PAR), air temperature, humidity, wind speed were also measured. The emission flux of isoprene in the rubber trees in wet season showed an obvious diurnal variation, and the clouds and precipitation could evidently decrease the emission flux of isoprene. The main energy processes related to biogenic isoprene emission were considered, according to the point of view of PAR energy transmission and conservation, and an empirical model for isoprene emission flux was established. The results show that the calculated values were close to the observed ones. Therefore, it is practical to build up a model for isoprene emission flux, based on physical principles and analysis of observational data measured under field conditions.