Investigation of the gravel filters effect's in influence optimization and the increasing of Soil moisture storage in Rainwater catchment system levels

Prolonged recently drought in East Azerbaijan has significantly been caused decreasing in the availability of water resources. In this time, gardens and cultivated area has been increased as irregular and disproportional in terms of climate changes. As the highest rates of water consumption is in the agricultural sector, it is very necessary to investigate the alternative water resources and optimization methods in water supplying. Now day, Rainwater harvesting is one of the practical methods for this mean. This research project was executed(in1ha area) with aims to apply gravel filter to infiltration and optimization as well as increasing water storage of harvested rain water into plant root zone. Research area is located in southwest hillslope of Own-Eb neh-ali mountain of Tabriz city. This project was conducted as Randomized Complete Block with five treatments and four replications. Treatments included: Treatment A, control, Treatment B, system by collecting pebbles and vegetation cover from its area with gravel filter, Treatment C, system by collecting pebbles and vegetation cover from its area without gravel filter, Treatment D, system by semi isolated area and gravel filter and Treatment E, system by semi isolated area without gravel filter. The effect of Gravel filter on the penetration rate and increasing of the water storage, were measured in 20 and 50 cm depths using TDR after each rainfall event. Results showed that mean soil moisture rate in Treatment D (semi-isolated system with gravel filter) in both 20 and 50 cm depth are 35.94 and 30.56 respectively and significantly higher than other treatments (p