Study On The Improvement Of Aeolian Sandy Soil By Vermicompost,Water Retention Agent And Water-fertilizer Intercropping

Aeolian sandy soil is a type of soil with a wide distribution and large quantity in the north of China.With the increasing conflict between human and land,there is an increasing demand for the development and management of sandy soils.In order to study the effect of different soil modification materials on the improvement of windy sandy soil,this study conducted a soil improvement and planting experiment in the flowing sandy land of Chengchuan Town,Etuokeqian Banner,Ordos City,the southwest edge of Mu Us Sandy Land,and applied vermicompost,water retention agent and NPK compound fertilizer and irrigation amount to windy sandy soil according to L₁₆（4⁵）experimental design.The soil quality was evaluated by the soil quality index based on the principle of minimum data set construction,and then combined with the comprehensive evaluation of plant growth and development TOPSIS to select the optimal combination of soil modification materials.The main findings of the study are as follows:（1）The soil moisture content increased significantly（p<0.5）with the increase in the amount of vermicompost and water retention agent applied,and the organic matter and nitrogen,phosphorus and potassium content increased significantly（p<0.5）with the increase in the amount of vermicompost and water retention agent applied,and increased significantly（p<0.5）with the increase in the amount of vermicompost and water retention agent applied,and decreased significantly（p<0.5）with the Soil conductivity decreased significantly（p<0.5）with increasing application of vermicompost and water retention agent.Vermicompost was best applied at the Q₃（22,500kg/hm²）treatment level and water retention at the B₁（75kg/hm²）treatment level.（2）Based on the principle of minimum data set construction,soil water content and meal content were the limiting and critical factors in the evaluation of soil quality of the ginseng fruit substrate,while total phosphorus and clay content were the limiting and critical factors in the evaluation of soil quality of the sour date substrate.The soil quality index of the soil modification material combination was improved compared with the lowest soil quality index,and Q?B₂F₃S₁（vermicompost:22,500kg/hm²;water retention agent:75kg/hm²;compound fertilizer:600 kg/hm²;irrigation:70%of maximum field water holding capacity）had the best effect on soil quality improvement.（3）Plant growth and development were closely correlated with the selected soil physicochemical indicators,which explained more than 90%of the plant growth and development,and the results of the comprehensive evaluation of plant growth and the results of the TOPSIS evaluation showed that Q?B₂F₃S₁（vermicompost:22,500kg/hm²;water retention agent:75kg/hm²;compound fertiliser:600kg/hm²;irrigation:70%of maximum field water holding capacity）was the most favourable combination for plant growth and development.