Influence of super absorbent polymer on soil water retention, seed germination and plant survivals for rocky slopes eco-engineering

To improve the utilization of water resources on rocky slopes eco-engineering, super absorbent polymer (SAP) with the function of water retention was applied. Super absorbent polymer in three levels, 0.15%, 0.3% and 0.45% were mixed with sandy loam soil. This study was aimed to evaluate the saturated water content, evaporation rate and water holding capability of SAP treated soils, determine seed germination rate and plant survivals in soil with SAP by absorbing and spraying experiments. The addition of SAP to the sandy loam soil resulted in a significant increase of the soil water retention compared to the controls. Also, the seed germination was significantly higher in SAP amended soil than in the soil without SAP, survival times of grass and woody were prolonged under water stress. 0.30% SAP treatment was the optimum selection for sandy loam soil improvement on steep rocky slopes. These studies indicated that SAP with good water retention properties, was very effective in enhancing water uptake and utilization of water for plants growth, and could be expected to have wide potential applications in rocky slopes eco-engineering.