## 4 Discussion
This result implies that more A-N might be absorbed by the kiwifruit tree after the EMs are added to the planting soil. According to the results, it can be deduced that the EMs can improve the A-N utilization rate in kiwifruit planting soil. The fruit maturity stage for kiwifruit occurs in July and August in the study area. In this stage, more various organic substances are needed to support the growth of kiwifruit. The demand of nitrogen relatively decreases in this stage. Thus, the A-N contents of the EG and the CK increased in July and August (Figure 2d). However, the A-N content of the EG was still obviously lower than that of the CK in July. The result may also be related to the promoting effect of A-N utilization of the EMs. In addition, the previous study reported that the overabundance of soil water content caused by rainfall could have decreased the A-N content [32]. In the experimental period, the rainy season occurred in July; thus, rainwater may also have washed away much A-N in the soil of the EG. In the study, the A-K-values of the EG were higher than those of the CK during May to June (Figure 2e), which is mainly caused by the function of potassium-dissolving through _Bacillus_ spp. [33]. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Month** & **Bacteria (\%)** & **Fungi (\%)** & **Actinomycetes (\%)** \\ \hline April & 59.76 & 24.17 & 16.07 \\ May (CK) & 78.24 & 9.46 & 12.30 \\ May (EG) & 50.00 & 25.00 & 25.00 \\ June (CK) & 61.00 & 18.00 & 21.00 \\ June (EG) & 44.10 & 24.70 & 31.20 \\ July (CK) & 96.24 & 0.00 & 3.76 \\ July (EG) & 73.95 & 11.53 & 14.52 \\ August (CK) & 79.21 & 16.50 & 4.29 \\ August (EG) & 92.46 & 6.13 & 1.41 \\ \hline \hline \end{tabular} CK: control group; EG: experimental group.  
\end{table} 
Table 2: Percentage of bacteria, fungi, and actinomycetes counts in kiwifruit planting soil. For A-P, the content of the EG was higher than that of the CK in May (Figure 2f). This is perhaps a result of the function of the phosphate solubilizing of _Bacillus_ spp., some of which are able to solubilize P through acidification or chelation, or enzyme action [33; 34; 35; 36; 37; 38; 39]. In Figure 2e,f, the A-P and A-K content followed the same variation trend in both the EG and the CK; the A-P and A-K contents reached their maximum in June, whereas the minimum A-P and A-K contents appeared in July. As discussed earlier, nitrogen is the highest element demanded to expand kiwifruit from April to June. The demands of potassium and phosphorus are not the highest in this stage. Therefore, the A-P and A-K contents improved with the passage of time from April to June in the EG and the CK. On the contrary, July and August are the main period of transformation of OM and formation of the quality of kiwifruit. In this period, the potassium and phosphorus demands increase. This led to the decrease of A-K and A-P in July and August in both the EG and the CK. Moreover, the A-K and A-P contents of the EG were lower than those of the CK in July and August. _B. subtilis_ can promote planting upon absorption of potassium and phosphorus [29; 30; 31], and _B. amyloliquefaciens_ can promote planting upon absorption of phosphorus [38; 39]. Thus, the results show that the EMs applied in the study might promote the absorption of potassium and phosphorus for kiwifruit planting. Our study found that the count of actinomycetes had significant negative correlation with TN content (\(p<0.05\), \(r=-0.887\)) (Table 1). Therefore, the TN content increased with the decrease in actinomycetes count. This result may be attributed to the TN absorption by actinomycetes. In the future, research should be concentrated on the specific causal mechanism of actinomycetes on TN in soil, as well as concerned about the ratio of actinomycetes in EMs, to retain or improve the content of TN.