Anabasis aphylla & Pteropyrum aucheri Canopy Cover Effect on Generating Stemflow in Arid Regions

Stemflow is a part of precipitation which enters in to the soil through stem and branches. In this paper, we studied the stem flow features of Anabasis aphylla as a bush and Pteropyrum aucheri as a shrub in Northwest of Isfahan. Stemflow production mechanism as well as the effects of canopy cover on this system was investigated during precipitation seasons in 2013 and 2014. A rain simulator was used to achieve this aim. Three individual for each species with different canopy coverage were selected. The results showed 13.4% of gross precipitation as stemflow for A. aphylla. However, it is 18.4 for P. aucheri. Furthermore the mean funneling ratio were calculated 29 and 40 for A. aphylla and P. aucheri, respectively. Totally, results clearly showed the positive role of stems and brunches in producing stemflow for both species. In addition, small and large plant showed significant different amounts of stemflow for both species indicating the effect of crown canopy on stem flow. Concerning bushes and shrubs, this study proves that stemflow changes in a large amount inter and intra various vegetative forms with different canopy cover.