# The Effect of Slow-Release Fertilizer on the Growth of Garlic Sports and the Soil Environment
## 3 Results and Analysis
### The Effects of Different Treatment Groups on Soil Nutrients  
As shown in Table 3, compared with those under the CK treatment, the T1, T2, and T3 treatments significantly improved the chemical properties of the soil, including increased levels of organic matter, total potassium, available potassium, and available phosphorus. The levels of available nutrients in all of the fertilized treatments were significantly higher than those in the non-fertilized control, aligning with the findings of previous studies which have confirmed that fertilization improves soil fertility. Among the treatments, T3 exhibited the greatest improvement, which can be attributed to the controlled nutrient release of the slow-release fertilizer. The combined effects of the physical coating and adsorption mechanisms enhanced the contents of available potassium, available sulfur, and exchangeable magnesium while simultaneously lowering the pH and increasing the organic matter content. These improvements are mainly due to the gradual nutrient release of the slow-release fertilizer, which minimizes nutrient loss; the calcium displacement effect of phosphogypsum, which alleviates soil salinization; and the adsorption capacity of bentonite, which enhances nutrient retention. As a result, the T3 treatment comprehensively optimized the soil's chemical properties, ensuring a continuous and balanced nutrient supply. [PERSON] et al. [63] demonstrated that the application of slow-release nano-fertilizers (with contents of nitrogen, phosphorus, potassium, magnesium, calcium, and humic acid of 26.0%, 17.0%, 13.0%, 0.2%, 0.9%, and 3.0%, respectively) could enhance the soil's nutrient content, increase the soil's enzyme activity, and improve the microbial environment, thereby reducing the nutrient loss and promoting a healthier soil ecological system. These findings highlight the high application value of such fertilizers. Replacing conventional chemical fertilizers with organic or slow-release alternatives has proven to be an effective strategy for improving both crop yield and soil quality. [PERSON] [64] reported that the substitution of chemical fertilizers with slow-release fertilizers led to notable improvements in soil quality and crop productivity. The study revealed that compared with conventional chemical fertilizer treatments, the use of slow-release fertilizers significantly increased the soil's organic matter content. Similarly, [PERSON] et al. [65] found that the application of slow-release potassium fertilizers significantly enhanced the concentration of available potassium in the soil. Compared with traditional potassium chloride treatments, this method satisfied the nutrient demands of maize during its later growth stages better. These findings are consistent with the results of the present study. Therefore, replacing conventional fertilizers with slow-release fertilizers could promote the sustained absorption of nutrients and enhance soil fertility while also reducing the overall usage of chemical fertilizers. This approach contributes to continuous crop yield improvements and maximizes the net economic benefits. Although this study demonstrates, through testing changes in the soil's chemical properties after fertilization, that the application of slow-release fertilizers can enhance the soil's fertility, it lacks research and analysis on the temporal dynamics of the soil's nutrient availability. Therefore, future work should investigate further how slow-release fertilizers, compared to conventional fertilizers, release nutrients gradually in the soil, improve fertilizer use efficiency, and support nutrient uptake by garlic seedlings better throughout their growth cycle. The ability of crops to absorb potassium and magnesium can also be evaluated by analyzing the soil's enzyme activity. Key soil enzymes involved in the uptake of potassium, magnesium, and sulfur include urease and phosphatase, which indirectly influence potassium availability by regulating the soil's pH or competing for adsorption sites.