Investigating the Influence of Pioneer Plants’ Stemflow on Soil and Concomitant Plants in Arid Zones

This study set out to investigate the influence of stemflow of Anabasis aphylla L. and Pteropyrum aucheri Jaub. & Spach on soil and concomitant plants in Central Iran. To this end, the stemflow was measured on ten mature plants with five replicates per species from March 21, 2014, to May 2, 2014. Moreover, the volume of collected flows was measured after each rainfall using measuring cylinders. Then, the volume was divided by the crown area to find the flow depth for each stem. On the other hand, to investigate the influence of stemflow on nursing understory plants, the plants were treated with and without stemflow at different depths. In this regard, the Lepidium sativum Linn was selected as the intended species to investigate the stemflow nursing effect of A. aphylla and P. aucheri.  The results of the study indicated that the average rate of stemflow in P.aucheri and A.aphylla ​​was 18.5% and 13.4% of gross rainfall, respectively. Furthermore, the average funneling ratio ​​was found to be 29 and 39.9 for A.aphylla and P.aucheri, respectively. The moisture, OM, and MWD obtained for the soil under A.aphylla and P.aucheri were significantly different when treated with stemflow in depths of 80 and 100 cm from the case when the underlying soil of the species was treated without streamflow. However, while the variations in soil’s pH were not significant at different depths in both treatments and bare soil, the variations showed a slight increase in A.aphylla compared to P.aucheri and bare soil. On the other hand, the investigation of the two treatments in terms of EC values ​​revealed that salinity was higher in the treatment without stemflow. It was also found that the efficiency of stemflow nursing was up to 10 cm and 7 cm in radius in P.aucheri and A.aphyll, respectively.