Abstract:

The study aims to clarify the spatial differences in soil fertility and characteristics of microbial diversity of vegetable fields in Xiaoshan District of Hangzhou, and provide a scientific basis for optimizing soil management strategies and promoting the green and sustainable development of the vegetable industry. Soil samples were collected from 16 vegetable fields (S1-S16) in the district, and physical and chemical indicators such as pH, organic matter, and nitrogen, phosphorus and potassium nutrients were determined. Illumina MiSeq high-throughput sequencing technology was used to analyze the diversity of soil bacterial communities. The results showed that the soil fertility in the study area exhibited significant spatial heterogeneity (moderate variation). The soil in the eastern part was weakly alkaline with severe salinization, while the soil in the southern part was acidic with higher contents of organic matter and total nitrogen, and available phosphorus and available potassium showed polarization due to differences in fertilization. Soil organic matter was significantly positively correlated with nitrogen, phosphorus, and potassium nutrients, pH was significantly negatively correlated with total nitrogen, and the planting age of protected vegetables had a highly significant positive quadratic relationship with soil electrical conductivity (R²=0.65, P<0.01). The dominant bacterial phyla were Proteobacteria, Chloroflexi, etc. Microbial diversity was higher in the southern and central old planting areas, and the community structure was divided into two groups based on soil salinization and fertility levels. Chloroflexi was significantly negatively correlated with pH (r=-0.53, P<0.05). In the future, measures such as reducing phosphorus fertilization, replacing chemical fertilizers with organic fertilizers, paddy-upland rotation, and improving irrigation and drainage in salinized areas should be adopted to regulate soil pH and fertility and enhance soil health.

Key words: protected vegetable, planting years, soil fertility, microorganisms, salinization, soil pH