Abstract:Iris narcissiflora is an endemic herb to western Sichuan Province, China, its current distribution range has been severely shrunk, and it was listed as a key national wild protected plant of grade II. However, the understanding of the population status and habitat characteristics of I. narcissiflora is very poor, which is not conducive to the study of its endangered mechanism and the formulation of conservation measures. The present distribution range of iris daffodil was investigated in detail to investigate the wild population status and habitat, especially the characteristics of the community. After extensive field surveys, I. narcissiflora was distributed in alpine shrubs or edge of spruce (Picea likiangensis var. rubescens) forests with the altitude of 3 779-4 100 m in Daofu County and Kangding City, Ganzi Prefecture, Sichuan Province, and the populations were small with 28 to 2 100 individuals. Based on current distribution, I. narcissiflora is reassessed as endangered (EN) according to the IUCN Threatened Species Assessment criteria B2ab(iii). The species composition of the community with I. narcissiflora was rich, the life type was mainly perennial herbs, with more temperate components. There was a significant negative correlation between species composition similarity and geographical distance between communities. A significantly negative relationship was observed between community similarity and geographic distance. The communities with I. narcissiflora could be divided into four types: spruce forest margin and alpine shrubs with Rhododendron websterianum, R. hippophaeoides and Salix myrtillacea as the dominant species, respectively. The habitat of I. narcissiflora was affected by road construction, grazing, natural succession and global climate change were also potential threats. According to the habitat conditions of different distribution sites, it was suggested to set up conservation areas, take appropriate measures to reduce the expansion of spruce in western Sichuan and the influence of human factors, and to carry out research on ex situ conservation technology.
