A new framework for evaluating land suitability for Goji (Lycium barbarum L.) cultivation across China

As a valuable Chinese medicinal herb and functional food, Goji (Lycium barbarum L.) berries have been consumed for more than 4500 years in China and have received extensive international attention. However, stakeholders have adopted traditional management strategies, and rational planning for national Goji cultivation is still lacking across China's pedoclimatic regions, greatly hindering efficient production and improving crop quality. In this study, a new framework applying to large-scale assessment of Goji cultivation suitability was proposed by integrating both a mechanistic model and an ecological niche model. A field survey was conducted across major Goji cultivation regions in 2023, including 255 Goji planting sites and 223 control sites. Fresh berry samples from 211 of these sites were collected and analyzed to establish relationships among Goji cultivation, production, and environmental conditions. The Maximum Entropy Model (MaxEnt) was trained to identify the potential areas suitable for Goji cultivation by integrating the Goji planting sites and environmental variables. Furthermore, advanced machine learning techniques, including K-means clustering and random forest, were adopted to quantify the responses of crucial Goji berry quality indicators to environmental factors. A multicriteria suitability evaluation model incorporating 13 indicators, carefully selected based on their relevance and data availability, was established, and a relatively objective grading and weighting system was derived to group four distinct suitability classes. The results revealed that the potential areas suitable for Goji cultivation covered approximately 184,117 km², with the most suitable areas accounting for approximately 16 % of the overall area, highly suitable areas accounting for 41 %, moderately suitable areas accounting for 24 %, and less suitable areas accounting for 19 %. This study assesses the suitability of Goji cultivation at a national scale, which may provide valuable insights for optimizing production and supporting informed decision-making across China and other similar areas.