Abstract: In order to explore the effect of agricultural photovoltaic system on soil quality, three treatments were set up: planting cabbage under photovoltaic panel (A), bare soil under photovoltaic panel (B) and open-field bare soil (CK). The changes of soil nutrient content, pH, conductivity and organic matter content before and after planting were measured. The results showed that shading combined with Chinese cabbage planting (A) significantly increased the contents of alkali-hydrolyzoble nitogen （increased by 11.84 mg/kg）, available potassium (increased by 148.00 mg/kg), available phosphorus (increased by 13.39 mg/kg) and organic matter (increased by 14.93 g/kg), but simultaneously aggravated soil acidification (pH decreased by 0.42) and salt accumulation (conductivity increased by 209.53 μS/cm). Only shading (B) inhibited the accumulation of water-soluble salts (conductivity decreased by 85.50 μS/cm), but led to phosphorus fixation (available phosphorus content decreased by 4.35 mg/kg) and available potassium nutrient loss (decreased by 49.61 mg/kg), highlighting the necessity of crop regulation. Open-field bare soil reduced water-soluble salt accumulation due to natural leaching (conductivity decreased by 94.63 μS/cm), but the loss of nitrogen-available nutrients was significant (alkali-hydrolyzed nitrogen content decreased by 33.32 mg/kg). The optimization strategies such as partition planting, application of corrosion-resistant materials and intelligent water and salt regulation were proposed to provide a scientific basis for the high-quality development of agricultural photovoltaic systems.

Key words: agriculture photovoltaic system, soil quality, crop cultivation, shading effect, dual regulation