Deploying photovoltaic arrays in degraded grasslands is a promising win-win strategy for promoting grassland restoration and resolving land use conflicts

Photovoltaic (PV) facility installation occupying large land areas gradually expands into vast grasslands. The construction of PV arrays should be synchronized with the establishment of fences to prevent grazing and human disturbance. However, it is still being determined whether deploying PV arrays in degraded grasslands has better restoration effects than common grassland fencing, achieving a win-win for grassland restoration and resolving land use conflicts. Here, we investigated soil and vegetation characteristics to assess the different impacts of PV arrays, fencing, and free-grazing on restoration in the degraded grassland in the Songnen Plain, Northeast China. The results showed that the PV arrays and fencing significantly improved soil and vegetation parameters, with the PV arrays dramatically increasing carbon and nitrogen storage in plants (including aboveground, underground, and litter) and soil. The mixed linear model analysis showed that the experimental zones had a significant influence on the carbon and nitrogen pools in plants and soil. Compared to single grassland fencing, the PV arrays significantly improved the carbon storage of plants and soil, with increases of 30.19% and 17.93%, respectively. Furthermore, there was an observed increase of 9.44% and 0.75% in the nitrogen storage. Soil pH and bulk density were the main factors influencing soil carbon and nitrogen storage in the fenced zones. Increasing soil moisture in the PV array zones resulted in higher soil carbon and nitrogen storage than in the fenced zones. The PV arrays showed a 78.61% increase in annual mean soil carbon sequestration rates compared to the grassland restoration measures reported in previous studies. Overall, the PV array zone superimposed the dual effects of PV panels and their fences, with the ecological indicators showing a greater positive influence than common grassland fencing. Our results suggested that deploying PV arrays was a win-win strategy for promoting grassland restoration and resolving land use conflicts in degraded grasslands.