Abstract: The global estuarine sand islands are facing the severe impact of high-intensity land-sea dynamic action, and the ecosystem is generally fragile, degraded and lost. Taking ecological restoration technology to restore the health of sand islands has become one of the main objectives of estuary management. In this paper, the degraded coastal section of the western part of Shajing Island, the largest Pinglu Canal estuary since the founding of the People 's Republic of China, is taken as the research area. This study first analyzes changes in the intertidal macrobenthic community following the implementation of near-natural bamboo fence restoration, based on transect survey data. These findings are then used to evaluate the overall ecological impact of this restoration technology in the region. The results showed that the macrobenthos before and after the restoration of Shajing Island were mainly arthropods, accounting for 62.5% and 66.67 %, respectively. The index of relative importance (IRI) of macrobenthos has increased from below 100 before restoration to over 100 in some sections after restoration; The Simpson (D) diversity index increased from 0.51 before restoration to 0.92 after restoration, significantly; The Shannon Wiener (Hʹ) diversity index increased from 1.08 before restoration to 1.55 after restoration, significantly. The mean Pielou (J) uniformity index remains stable. The average density of macrobenthos increased from 41.6ind·m-² before restoration to 144 ind·m-² after restoration, an increase of approximately 246%. The W value of the abundance/biomass comparison curve (ABC curve) of macrobenthos increased from -0.03 before restoration to -0.01 after restoration; The pollution index (MPI) of macrobenthos increased from 1.53 before remediation to 2.08 after remediation. By comparing the parameters before and after restoration, the following conclusions were drawn: the community structure of macrobenthos before restoration was simple and fragile, lacking dominant species. After restoration, the community broke from the state of no dominant species before restoration, and a representative main population appeared, indicating that the community structure tended to stabilize; Significant improvement in biodiversity before and after restoration, with a significant increase in the average density of macrobenthos and no significant change in evenness; Although the restored community of macrobenthos is still severely disturbed, there has been a significant improvement compared to before the restoration. This study proves through the investigation of macrobenthos that the bamboo fence near nature restoration project can effectively improve habitat stability and promote the restoration of biodiversity. This study provides scientific support for the restoration of damaged habitats at the estuary of the Pinglu Canal.

Key words: Pinglu Canal, Estury, Near-natural restoration, macrobenthos