Soil pathogenic fungal groups and soil nutrient cycling under land use practices in Liupanshan Mountain in China

Abstract Different land‐use practices in temperate forests strongly affect soil quality and soil microbial communities, whereas the assembly and interactions of soil functional fungal communities provide positive feedback. Therefore, the effects of forest ecosystem degradation on the composition of functional soil fungal community and soil nutrient cycling are of particular importance. We studied forest ecosystems in the Liupanshan Mountains in the northwestern part of the Loess Plateau and analyzed the relationship of soil fungal community and soil nutrient cycling under different land use practices (natural forest [NF], plantation forest, and farmland [FL]). The results showed that soil pH and electrical conductivity were the highest in FL, whereas the soil carbon cycle index and nitrogen cycle index decreased. The soil total phosphorus content did not change significantly with an increase in available phosphorus content. The change from NF to FL significantly increased the number of operational taxonomic units, diversity, and richness of soil fungal communities. The composition of the soil fungal communities was also strongly influenced by carbon and nitrogen cycle indices. In addition, FL reclamation increased the complexity of the soil microorganism co‐occurrence network, and the interrelationships between soil functional fungal community were enhanced. Pathogenic fungal communities were enriched in FLs, and their relative abundance was significantly regulated by environmental factors such as pH and the ratio of nitrogen to phosphorus. The soil pathogenic fungal community affected carbon and nitrogen cycle indices to varying degrees.