Abstract: Target tree management can adjust stand structure, alleviate tree competition, and improve soil quality. Taking Larix gmelinii natural forest as the control, we explored the characteristics of soil fungal communities by high-throughput sequencing technology and investigated the relationships among fungal communities, physicochemical properties, and soil extracellular enzyme activities of L. gmelinii plantations managed by the target tree and that not managed by the target tree. The results showed that compared with natural forest, target tree management reduced stand density and significantly increased the contents of total carbon, total nitrogen and nitrate by 33.2%, 58.5% and 38.4%, respectively. Compared with non-target tree management stand, the contents of total carbon, total nitrogen, and nitrate in target tree management stands significantly increased by 0.3%, 14.8% and 10.0%, respectively. Compared with natural forest and non-target tree management stand, the β-glucosidase and acid phosphatase activities in target tree management stands significantly increased by 13.6% and 37.0%, 37.3% and 39.5%, respectively. Target tree management enhanced α diversity of soil fungal community, altered species composition and functional groups of fungal community. The relative abundance of Mortierellomycota significantly increased by 200.0% and 8.3% in target tree management stand compared with the natural forest and non-managed stand of the target trees. Redundancy analysis indicated that soil nitrate content, C:N and β-glucosidase activity were the main factors affecting soil fungal community. Target tree management ultimately improved soil fungal community structure by reducing stand canopy density, adjusting light conditions, and then increasing soil water content, nutrient contents, and extracellular enzyme activities.

Key words: target tree management, soil extracellular enzyme, soil fungi, high-throughput sequencing