Evaluation of Rainwater harvesting Methods in Increasing Soil Moisture and Pistachio Seedling Growth

Rain water harvesting is a utilized method to develop surface water resources in dry regions، which can provide water for domestic، livestock and agriculture uses in small scales. To evaluate the impact of the rainwater harvesting systems on soil moisture and pistachio seedling growth، an experiment was conducted as a randomized complete block design with four treatments and three replications during the years 1388 to 1389 in Khaje Research Station، East Azerbaijan province، Iran. Each rain harvesting plot acted as a watershed system and its runoff was conducted to runoff collection pit. Treatments at each watershed were established with changing of soil texture and putting water harvesting fictiles. Treatments included: Treatment A، Control، in this treatment the excavated pit was filled only with the soil obtained from there; Treatment B، inside of the excavated pit was filled with a mixture of perlite; decomposed organic matter and soil، with volume ratio of 1-1-2; Treatment C، the excavated pit was equipped with three fictiles (10 cm diameter and 70 cm height) which are installed at three equal intervals; Treatment D، with two columns of gravel which were created in the vicinity of the excavated pit by distance of 10 cm from its wall. In each pit، a pistachio seedling was planted and also a pair of TDR sensors was placed to measure soil moisture. Results showed that soil moisture capacity in comparison to control increased significantly. The soil،s mean volumetric water content for the gravel treatment during the two years was the highest and those of the fictile، perlite and control treatments were in the next levels، respectively. Also، the effects of the treatments on plant height، leaf area and collar diameter were statistically significant (p<0. 01). The Maximum values of seedling height، collar diameter and leaf area belonged to the gravel treatment and the minimum of them were for control.