Plant Diversity and Community Structure of Subalpine Wetlands in Fenghuangshan, Northeast China

Wetlands play essential roles in sustaining biodiversity, maintaining hydrological stability, and regulating the climate. Subalpine wetlands are particularly rare in Northeast China, yet their floristic composition and diversity patterns remain poorly studied. To fill this knowledge gap and address the lack of baseline plant data for this region, this study conducted systematic field surveys in the subalpine wetlands of Fenghuangshan, Heilongjiang Province, with the aim of assessing plant diversity, dominant floristic types, and community differentiation. The result showed a total of 100 vascular plant species were recorded, belonging to 38 families and 69 genera. Four nationally protected Class II species were also identified, underscoring the region’s conservation importance. Across the three representative plant associations, the Carex limosa-Carex lasiocarpa association exhibited markedly higher species richness, Simpson diversity, and Shannon diversity than both the Salix sericeo-cinerea and Pinus pumila-Rhododendron aureum associations, reflecting pronounced community-level variation in biodiversity. The floristic characteristics at the species level also pointed to a predominantly temperate distribution and showed a pronounced vascular plant flora, which is characterized by the ecotone between temperate and boreal biogeographical zones, directly underpinning the different composition of the communities. This study presents a detailed baseline assessment of plant diversity and floristic composition in the Fenghuangshan subalpine wetland ecosystem. In response to the limited understanding of such ecosystems in East Asia, this research provides crucial foundational data. Furthermore, by contextualizing these results with ecological patterns observed in Northern European wetlands, the study places the local findings into a broader, global perspective. The results offer essential scientific support for biodiversity monitoring, ecological conservation planning, and the future restoration of subalpine wetlands in Northeast China.