Multi-element Interactive Improvement Mechanism of Coal Fly Ash-Based Soil Conditioner on Wheat

Globally, coal fly ash (CFA) is a bulk industrial solid waste that is difficult to be disposed of, which posed serious environmental risks to the atmosphere, water, and soil. Besides, the food crisis outbreaks worldwide. In this case, the utilization of CFA to produce soil amendments is expected to improve the soil quality and to increase the grain yield. This paper took the soil conditioner prepared by chemical activation method as the research object, analyzed, and found out its mechanism when increasing the yield and improving the quality of crops. First, the simulated hydroponics method was used to identify the key yield-increasing factors in the soil conditioner as well as the effects of those factors by taking the plant height, stem thickness, dry weight, and fresh weight of wheat as indicators at the early stage of growth. Then, SPSS was used to analyze the interaction among K, P, and other four middle trace elements in the stem and the leaf of wheat. The results showed that for wheat seedlings, there were strong interactions between Fe and Mg, Mg and Ca, and Ca and Si. Fe had a significant enhancement effect on the fresh weight of wheat seedlings. Mg had a significant enhancement effect on both the fresh weight and dry weight of wheat seedlings. Si can greatly enhance the dry weight and plant height, and Ca can greatly increase the stem thickness. It was also found that the soil conditioner and the basic N, P, and K fertilizer had a good mutual promotion effect. Among the four elements, Mg and Si are the key growth factors. When the nutrient elements were relatively poor, the increase of Mg by 50% would lead to the growth of the fresh weight of wheat seedlings by 65%; when the content of active Si increased by 50%, the fresh weight would increase by 52%. Therefore, the soil conditioner prepared by modified treatment of CFA owns a good application prospect to increase the yield and quality of crops.