Study of different types of mulch efficiency on soil retain moisture in planting seedlings in arid areas by black saxaul (Haloxylon ammodendron) in Semnan province

The most appropriate method of maintaining soil moisture in planting in dry areas is to cover the surface of the soil around the planted seedlings with natural and artificial mulches. To investigate the effect of different types of mulch in soil retain moisture, two types of natural and artificial mulch were used around the seedlings. This design is in the form of a complete random block with two main treatments including natural cover (gravel and sand) and artificial cover (light and black plastic) and four secondary treatments including pebbles, sand, light plastic, and black plastic and in three areas of Semnan, Ghoshe, and Damghan was performed. A control group was also considered. Each sub-treatment was planted in three replicates and 25 samples (black saxaul) were planted in each replicate. Immediately after planting the seedlings and irrigation, the mulch cover was placed around the seedlings. The soil moisture was measured by TDR device at a 10-day interval. The results related to the soil moisture showed that the level of the soil moisture in the black plastic treatment was significantly higher than other mulches. The results of the height of seedlings showed that the black plastic and control groups had the greatest effect on the soil retain moisture. Despite the difference in the soil moisture percentage in all types of natural and synthetic mulches, this difference did not show any significant change in the studied areas. The results of variance analysis of the seedling height showed that the differences in natural and artificial mulches and the control group were significant at the 99% level, but this was not significant in different areas. Examining the correlation between the seedling height and soil moisture percentage in different treatments showed that the highest correlation was in the sand treatment (R2 = 78.8).