Impact of Planting Eucalyptus Species on Floodwater Spreading: a Case study of Kowsar Aquifer Station, Fasa, Iran

Kowsar Floodwater Spreading, Aquifer Management, Training and Extension Station was established in 1982 on the Gareh Bygone Plain at 1140 m above sea level. The area has an arid climate and is located 190 km southeast of Shiraz, Iran. Thirteen floodwater spreading systems, covering 2445 ha, were designed and constructed during the 1983-2003 period to artificially recharge groundwater. Eucalyptus and Acacia species have always been considered for plantation in arid areas due to their drought resistance, flexibility in harsh habitat conditions, and the use of their wood and other by-products. Results of previous field experiments showed that E. microtheca, A. salicina, A. victoriae, E. oleosa, and E. camaldulensis were very successful, with more than 80% survival at the station. Therefore, more than 600 hectares of extensive and 100 hectares of intensive forest plantations with Eucalyptus and Acacia species have been established in the region.  Using the clipping and weighing method and organic carbon measurements in the laboratory, carbon storage capacity in Eucalyptus and Acacia forests at the station was estimated to be 7.8 tonnes/haannually. The average total dry biomass of E. camaldulensis trees in this area during the study period (16 years) was 247.07 tonnes/ha, of which 136.66 tonnes were trunk timber, 46.72 tonnes were leaved branches, and 39.94 tonnes were bark. Eucalyptus species flower twice a year in this area, providing  a source of pollen and nectar throughout the year for beekeeping. The average honey production at this station was 11 kilograms/hive. Moreover, the area attracts many eco-tourists, particularly during the holidays because of the beautiful landscape of the forest in a desert region. As Eucalyptus species use large amounts of water, it is proposed to replace these species with less water-demanding trees.