TANG Jialin, LIU Zhaoming, LIU Jielin, WANG Hongbao, LIU Xiangping
To examine the effects of photovoltaic panel shading on the quantitative characteristics of different plant communities and soil physicochemical properties in the grassland region of the Songnen Plain, a meadow steppe located at the National Photovoltaic Energy Storage Experimental Station in Daqing City, Heilongjiang Province, was selected as the study site. Three plant communities dominated by Leymus chinensis, Puccinellia tenuiflora and Phragmites australis were investigated in the areas beneath photovoltaic panels and in adjacent inter panel space. Community characteristics, soil physicochemical properties, and their relationships were compared between these two habitats. The results showed that, among the three communities, the L. chinensis community beneath the panels had fewer species than that in the inter panel areas, and all α-diversity indices were significantly lower (P<0.05). However, its coverage, plant height, and aboveground biomass were significantly greater beneath the panels, increasing by 12.60%, 14.70% and 58.30%, respectively (P<0.05). In the P. australis community, coverage beneath the panels was significantly lower, whereas plant height was significantly greater than in the inter panel areas (P<0.05). In the P. tenuiflora community, coverage beneath the panels was significantly lower, aboveground biomass was significantly lower, with a decrease of 89.47% (P<0.05). For all three communities, soil moisture content beneath the panels was significantly higher than in the inter panel areas, while electrical conductivity was significantly lower (P<0.05). In the P. australis community, soil total nitrogen, available nitrogen, available potassium, and organic matter contents beneath the panels were significantly lower than those in the inter panel areas (P<0.05). In the P. tenuiflora community, soil total nitrogen and organic matter contents beneath the panels were significantly lower, whereas available phosphorus content was significantly higher (P<0.05). In the L. chinensis community, no significant differences were detected in soil properties other than moisture content and electrical conductivity. Correlation analysis revealed that soil moisture content was mostly significantly positively correlated with community coverage and aboveground biomass in both habitats, indicating that soil moisture content was a key soil factor regulating grassland productivity. In conclusion, photovoltaic panel shading increased soil moisture content and thereby promoted aboveground biomass accumulation in L. chinensis and P. tenuiflora communities.