## 4 Discussion
### Effects of Treatments on Crop Agronomic Attributes  
Determining the optimum N application method is an operative approach to meet crop economic benefits whilst decreasing the environmental hazards. Crop production is a normally used gauge for defining ideal N application methods [66]. The results of our study showed that NT, NTN, NTM, and NTNM treatments increased plant height, grain number per spike, 1000-grain weight, biomass, and grain yield to a greater extent than CT, CTN, CTM, and CTNM treatments, which indicated that no-till farming combined with inorganic and organic N fertilizer could increase the yield of wheat, which was consistent with the results of previously published studies [8; 67; 68]. This may be because no-till did not disturb the soil layer; it maintained the original soil capillary system in the wheat field; the soil bulk density was suitable; and there were more capillary pores, which avoided hardening of the soil caused by overly wet tillage. [PERSON] et al. [69] drew a same conclusion for a short-term wheat study. In addition, our results demonstrated that the nutrient status of no-tilled treatments is significantly increased, which improved the soil's ability to retain both water and fertilizer; it led to improve crop production [24], which is consistent with the finding of [PERSON] et al. [68] and [PERSON] et al. [70]. Nevertheless, there were also scholars who found that no-tilled soil and fertilization did not significantly affect [71] or reduce the crop productivity [72]. It is believed that organic fertilization could result in, notably, N immobilization and, accordingly, result in lower crop productivity [73]. Moreover, the combination of organic and inorganic N fertilizer can not only ensure the long-term nutrient demand of the soil but can also rapidly meet the nutrient requirement of crops, so that the nutrient demand and the supply of soil nutrients can be coordinated [74] to create a good growth environment and increase production. In addition, our study found a correlation between spring wheat yield and soil quality attributes. Our results showed that spring wheat yield was significantly positively correlated with SWC, SOC, TN, NH\({}_{4}\)\({}^{+}\)-N, C/P, and N/P, and spring wheat yield was negatively correlated with soil NO\({}_{3}\)\({}^{-}\)-N content and C/N. This is because the increase in SWC, SOM, and TN content will enhance root system activity and increase the ability of the root system to absorb nutrients. Increased SWC, SOM, and TN content also provide carbon and N for microbial growth, which will increase the rhizosphere microbial community, enhance the exogenous influence on root growth, accelerate the growth rate of crops, improve crop biomass, and enhance photosynthesis [75], which will increase yield. In addition, the increase in SOM and TN content can effectively prevent soil hardening, enhance soil fertility, and provide better site conditions for crop growth [76]. In our study, we found a significant positive correlation between soil NH\({}_{4}\)\({}^{+}\)-N content and yield because the trend in NH\({}_{4}\)\({}^{+}\)-N content was consistent with that of TN, because it mainly came from the mineralization of TN [56]. Additionally, there was a positive correlation between yield and C/P and N/P, because in the state of relatively stable phosphorus in farmland soil, the greater the carbon and N, the greater the C/P and N/P and the higher the content of carbon and N in soil, so as to improve the crop yield [60]. The yield was negatively correlated with soil NO\({}_{3}\)\({}^{-}\)-N content, because the excessive accumulation of NO\({}_{3}\)\({}^{-}\)-N leads directly to secondary salinization, an imbalance in the nutrient supply, and structural damage, as well as other problems. In addition, excessive NO\({}_{3}\)\({}^{-}\)-N levels will cause a large amount of NO\({}_{3}\)\({}^{-}\)-N leaching, which in turn causes soil pollution, inhibiting crop root development, and ultimately greatly affects crop growth, which can reduce yield [77].