Niches and community stability of dominant herbaceous species in the forest and creek ecotone of Dehang Geopark

[Objective] The study aims to explore the characteristics of ecological niche, interspecific connectivity, and community stability of dominant species in the herbaceous community of the forest and creek ecotone in Dehang Geopark, with the expectation of providing a theoretical foundation for the protection of the herbaceous communities and sustainable development in the area. [Methods] The authors employed a suite of analytical methods including niche determination, variance ratio, Chi-square test, Spearman rank correlation test, and association coefficient to examine the ecological niches and interspecific associations of the dominant herbaceous species within three creeks in Dehang Geopark. [Results] (1) In the Jiulong Creek and Yuquan Creek, Pilea pumila occupies the widest ecological niche, whereas in the Hangxia Creek, Boehmeria spicata has the broadest ecological niche. The average ecological niche overlap indices for Jiulong Creek, Hangxia Creek, and Yuquan Creek are generally low. This indicates that the interspecific competition among dominant species in the herbaceous communities of the forest and creek ecotone is weak, and there is not a high degree of similarity in the demand for environmental resources. (2) The overall and interspecific associations of the herbaceous plants in the three streams are mainly characterized by non-significant negative connections, with relatively low interspecific connectivity, and are mostly independently distributed. (3) The community is currently in an unstable state, and the succession and development of the herbaceous community are influenced by both internal and external factors of the community. [Conclusion] In Dehang Geopark, the herbaceous community in the forest and creek ecotone has weak interspecific associations, with species being independently distributed, indicating that the community is in an unstable state.