Abstract: We investigated the effects of environmental heterogeneity in photovoltaic (PV) field on soil nutrient and fertility quality of the vegetation restored soil in PV field of rocky desertification area, aiming to provide scientific and technological support for ecological restoration in fragile rocky desertification area. The horizontal (intervals/underneath of panels and front/rear of panel eaves) and vertical (0-20, 20-40, and 40-60 cm) spatial differentiation characteristics of soil nutrients in the vegetation restoration area were analyzed by principal component analysis and one-way ANOVA to assess the effects of shading by PV panels on soil fertility. The results showed that different degrees of shading of PV panels had minor effects on soil water-soluble organic carbon and available phosphorus concentrations, with no differences among different locations (P>0.05). Total nitrogen, total carbon and nitrate nitrogen concentrations showed no difference in the location under the panels compared with the location between the panels (P>0.05), and available potassium concentration was significantly elevated (P<0.05). In addition, different degrees of shading of PV panels did not affect soil quality index (SQI) (P>0.05), and soil nutrients had significant surface aggregation characteristics, indicating that the protection and improvement of topsoil in the PV field is of great significance for vegetation restoration.

Key words: rocky desertification, photovoltaic power station, soil fertility quality, spatial differentiation, surface aggregation characteristic.