Abstract: ObjectiveIn order to improve the ecological environment and sustainable development of vegetation in the Hutuo River Basin, this paper conducted in-depth research based on the poor soil structure and weak water and fertilizer retention capacity of the Hutuo River sandy land in Shijiazhuang City.MethodFive different soil water retention agents (attapulgite sodium polyacrylate water retention agent, biochar and bentonite water retention agent, humic acid water retention agent, polyacrylate water retention agent, and starch SAP) were selected as the research /t/nobjects to explore the improvement effect of different water retention agents on sandy soil. Furthermore, through orthogonal experiments, different proportions of water-retaining agents, corn straw and biochar were added to the soil to explore the water and fertilizer retention effects of soil under different substrate ratios.ResultWhen the dosage of water retention agent was 1%, the soil moisture content of the other water retention agents was more than 85%, and the soil conductivity was more than 1500 us/cm, except for humic acid water retention agent and polyacrylate water retention agent. However, soil compaction occurred when 0.1%-1% dose of humic acid water retention agent and starch-based SAP water retention agent was applied at a dose of 0.5%-1%. Therefore, attapulgite sodium polyacrylate water retention agent is more suitable for sandy soil in this area, and the water retention effect is better. The effects of water-retaining agent, corn straw and biochar on substrate soil moisture were arranged from largest to smallest: water-retaining agent>corn straw> biochar. The effects on the conductivity of substrate soil were as follows: water retention agent> biochar> corn straw. With the increase of the amount of water retention agent, the soil moisture and conductivity were significantly higher than those of the control group. However, with the addition of corn straw, its effect on soil moisture content and conductivity gradually decreased. When the water retention agent is 10g: 990g, corn straw 0g, and biochar 20g, the water retention performance of the soil is the best.ConclusionIn conclusion, attapulgite sodium polyacrylate water retention agent has the best effect. The optimal water-holding performance ratio of the substrate was as follows: water retention agent: 10g:990g of soil, 0g of corn straw per kg of substrate, and 20g of biochar per kg of substrate, which was suitable for ecological restoration and plant growth of sandy soil in the Hutuo River Basin.