Objective This study was conducted against the background of functional degradation of riparian ecosystems during urbanization, focusing on the construction of green space landscape projects in the Liuxi River Ecological Protection Area. The aim was to explore the mechanisms by which landscape construction influences soil microorganisms in grassland and woodland ecosystems.

Method Based on Illumina MiSeq high-throughput sequencing technology combined with measurements of soil physicochemical properties, we systematically analyzed the changes in soil microbial community structure before and after landscape construction and their relationships with soil environmental factors.

Result The results showed that: (1) Landscape construction increased Soil Organic Matter, Total Nitrogen, and Available Phosphorus contents and enhanced Dehydrogenase activity, and decreased Available Potassium content and Urease activity in both grassland and woodland soils. Among these, the increases in Soil Organic Matter content (by 15.51% and 26.49%) and Dehydrogenase activity (by 213.11% and 301.44%) were statistically significant (P < 0.05) for grassland and woodland, respectively. (2) After landscape construction, the dominant bacterial genera were norank_f__Xanthobacteraceae, norank_f__norank_o__Vicinamibacterales, and norank_f__norank_o__Gaiellales, while dominant fungal genera were Saitozyma, unclassified_k__Fungi, and Mortierella. (3) After landscape construction, the Shannon index of soil bacterial communities in woodland increased significantly (P < 0.05), while the Chao1 indices of bacterial and fungal communities in both woodland and grassland, as well as the Shannon index in grassland, showed no significant changes (P > 0.05). The Nestedness index of soil microorganisms showed a decreasing trend after construction, but, similar to the Turnover and total β-diversity indices, the changes were not significant(P > 0.05). (4) After landscape construction, the bacterial and fungal co-occurrence networks of both grassland and woodland exhibited a higher average degree and lower modularity, indicating more complex microbial interactions and enhanced cooperation among functional modules.

Conclusion Landscape construction improved soil physicochemical properties and enzymatic activities, thereby indirectly regulating bacterial and fungal community structures and strengthening their correlations with soil nutrients and enzyme activities. These findings indicate that human-mediated landscape construction can optimize the soil ecological functional network, enhance ecosystem restoration capacity, and provide scientific support for the ecological restoration and health maintenance of the Liuxi River riparian zone.