## 4 Discussion  
### The Effects of Changing to Cash Crops on Basic Soil Properties in Moso Plantations  
The basic properties of soil are of great significance in maintaining soil productivity and ensuring animal and plant health [22]. Organic matter provides an abundant carbon source and energy for soil microorganisms, which promotes their activity and diversity [23]. In this study, compared with Moso plantations, the soil organic matter content was significantly increased after the conversion to cash crops, indicating that Persimmon and Tea-oil could effectively increase SOM content and improve soil quality. At the same time, the contents of TN and TK also increased after Moso was replanted with different crops, similar to the study by [PERSON] et al. [24], which proved that intercropping with Persimmon trees improved SOM, AN, TP and TK content in apple rhizosphere. The increase in soil TN content can promote plant photosynthesis, improve microbial activity, further enhance carbon input and nitrogen mineralization, and thus improve nitrogen supply in plants [25]. The soil planted with Persimmon showed higher MBP content, which might be related to the dissolution of soil phosphorus by root exudates of Persimmon and the promotion of microbial activity. In addition, it was found in the study that the soil pH value generally showed a downward trend after replanting, which may be due to the secretion of acidic substances by the roots of Persimmon and Tea-oil [16]. The above results indicate that crop replanting can significantly change the biological and chemical properties of soil, but its long-term effects need to be further verified. Changes in the Abundance of Phosphate-Functional Flora and Related Genes After the Conversion of Moso Stands to Cash Crops  
Soil microorganisms are important participants in soil metabolic activities [26]. By analyzing the number of P-functional bacteria and the abundance of P-functional bacteria under different crop cultivation, we found that the total number and unique number of P-functional bacteria in Persimmon soil were the highest, indicating that the microbial community involved in P cycling in Persimmon soil was the most diverse. In Persimmon soil, Pseudomonas and Acidobacteriota increased by 77.62% and 30.39%, respectively, compared with Moso soil. A similar trend was observed in Tea-oil soil. These results suggest that the abundance of these dominant bacteria increased after planting cash crops, which is consistent with previous studies [27]. _Pseudomonas_ is a well-known plant growth-promoting bacterium (Siderophores, IAA, NH\({}_{3}\), HCN, and P solubilization), and it is involved in bioremediation as well. In addition, _Pseudomonas_ also produces active secondary metabolites, thereby acting against the pesticide, making it a significant biological control agent [28]. Acidobacteria members in plant-soil ecosystems play pivotal ecological roles, including modulation of biogeochemical cycles and influencing plant growth [29]. In contrast, the abundance of Actinomycetota and Chloroflexota in Persimmon soil decreased by 55.15% and 79.96% compared with that of Moso soil. They play a major role in the cycle of organic matter, inhibit the growth of several plant pathogens in the rhizosphere, break down complex polymer mixtures in dead plant, animal and fungal matters, and produce many extracellular enzymes [30]. Their decline could mean that soil ecosystems are less buffered against environmental stress and more vulnerable to outside disturbances. The relative abundance of _Gemmatinomadata_ in Tea-oil soil also showed a decreasing trend compared with that in Moso soil, decreasing significantly by 90.50%. Interestingly, it was found that _Camellia_ was a unique dominant bacterium in Tea-oil soil, and _Candidatus-Acidoferrin_ was a unique dominant bacterium in Moso soil and Tea-oil soil. This reflects the high adaptability of these microorganisms to specific soil environments and their key role in soil nutrient cycling and soil structure improvement.