Effect of natural and artificial moisture absorbents on delay of permanent wilting point coefficient

Management practices and applying advanced techniques for conserving soil moisture is an appropriate way to exploit water resources. In this research, the effect of some organic wastes and a superabsorbent on soil available water and delay in permanent wilting point of a soil in steep slopes of Roodbar, Guilan province was investigated. Treatments including 10, 20 and 50% volumetric of tea waste, olive waste and municipal waste compost with the values 1, 2, 4, 8 and 16 g of a super absorbent (A200) in a completely randomized design were used in a roofed outdoor of Islamic Azad University at temperature range of 28-26 °C. In order to provide moisture retention curve and determination of field capacity (FC) and wilting point (PWP) in treatments from filter paper method was used. After soil saturation, the time to reach a saturated soil to PWP was calculated. Results showed that the effect of treatments on the moisture coefficients of FC and PWP was significant at 1% level. The most significant delays in PWP coefficient (at 1% level) in 50% municipal wastes compost and 16 g/kg superabsorbent respectively with a delay of 19 and 30 days were obtained. In general, the use of agricultural wastes (10%) in combination of superabsorbent (a rate of 5 g/kg) is associated with favorable outcomes.