Exploring the interaction mechanism of natural conditions and human activities on wetland ecosystem services value

Understanding the driving mechanism of natural conditions and human activities on wetland ecosystem service value (WESV) change is important for the sustainable development of wetland resources. The existing studies often analyze the direct effects of natural conditions and human activities on WESV, however, the interaction mechanism of them on WESV is still unclear. Therefore, based on the remote sensing image data of Liaoning Province China in 1990-2020, this paper combined Emergy with Partial least squares-structural equation model (PLS-SEM) to evaluate main WESV and explore the interaction mechanism between socio-economic development factor (Fsed), climate factor (Fcl), environment factor (Fen)and terrain factor (Fte) on WESV change. The results showed that the provisioning (WESVP) and regulating (WESVR) services value increased by 6.93 E+14 and 3.01 E+14 solar emjoules (sej), respectively, while the cultural services value (WESVC) decreased by 1.50 E+14sej. Overall, the total value of wetland services value (WESVT) increased by 8.45 E+14sej during the study period, with a growth rate of 37.88%. Fsed was the most significant factor driving WESV growth, with path coefficient of 0.53, followed by Fen and Fte, with path coefficient of 0.23 and 0.20, respectively, while Fcl had the greatest negative effect on WESV, with path coefficient of-0.18. From the perspective of the interaction between each factor, Fcl weakened the positive effect of Fsed and Fen on WESV, at the same time, Fsed weakened the positive effect of Fte on WESV. Through the indirect influence of Fte, the adverse effect of Fcl on WESV was further enhanced. This study innovatively revealed the interaction mechanism of natural conditions and human activ-ities on WESV change, and the results could provide scientific basis for the management and sustainable development of wetland resources.