Abstract:Ottelia cordata, a wild plant under State second-class protection, likes to be grown in clean water, and is extremely sensitive to environmental changes. It is one of the key indicator species for testing wetland environment and climate change. In China, it is only distributed sporadically in volcanic lava wetland in northern Hainan, the survival condition is not optimistic. The study of potential habitat selection and spatial pattern evolution of O. cordata population will help strengthen the conservation of endangered species and the restoration as well as the management of wetland ecosystem. Based on GIS platform and MaxEnt model, combining with climate, topography and soil factors, the environmental limiting factors of O. cordata population and the evolution pattern of potential suitable habitat in the context of climate change were studied. The results showed that O. cordata population was sensitive to temperature difference and precipitation change. Besides, isothermality, precipitation in the coldest quarter, type of soil and annual precipitation were key environmental factors affecting the distribution of O. cordata population. Under the background of climate change from the middle Holocene to current to 2070s, the area of suitable habitat of O. cordata decreased first and then increased, and the distribution center showed a transfer pattern from southwest to northeast to southwest. Under the future climate scenarios, the highly and moderately suitable habitats were decrease, while the low suitable habitats will increase. The new habitats will appear in the southern region, and the suitable habitats will decrease in the northeast, northwest and southwest. Therefore, the potential habitat selection and spatial distribution characteristics of O. cordata population were discussed from the perspective of climate environment, which could provide reference and theoretical basis for endangered species conservation, wetland management and biodiversity maintenance.