Abstract: Aims Plant sexual systems is an important reproductive role that affects plant mating, genetics, evolution, and species distribution. They are classified into three categories based on the floral organ's pistil and stamen arrangement: hermaphroditism, dioecy, and monoecy. Methods This article takes forest communities in Daiyun Mountain (elevation 900-1600 m) as the research object, analyzing changes in the quantitative characteristics of woody plant sexual systems and investigating their correlation with environmental factors via Mantel correlation analysis. Important findings The study area encompassed 85 woody plant species, with 49 hermaphroditic (57.6%), 26 dioecious (30.6%), and 10 monoecious (11.8%) species. Altitudinal increase led to a significant rise in the number of hermaphroditic and dioecious individuals, with no significant change in their species ratio, while monoecious individuals' number and species ratio significantly declined. The Shannon Wiener index and Pielou evenness index for sexual systems generally decreased with altitude, whereas the Simpson dominance index remained stable. Effective phosphorus and soil temperature were identified as the primary drivers of altitudinal changes in sexual systems characteristics. In conclusion, the quantitative characteristics of the sexual systems of woody plants on the altitudinal gradient of Daiyun Mountain showed significant differences, and the altitudinal distribution of the sexual systems was highly sensitive to environmental changes, indicating that plants adapt to environmental changes by regulating the composition of their reproductive systems, thereby ensuring the continuous survival and reproduction of their populations.

Key words: Key words Daiyun Mountain, altitudinal gradient, sexual systems, quantitative characteristic, environmental factors