关键词: MaxEnt模型, 潜在分布, 优势物种

Abstract: By using Shannon index and Pianka overlap index, and in combining with Detrended Corresponding Analysis (DCA), this paper studied the niche breadth and overlap of the dominant species along the North Trunk of Wanjiazhai Yellow River Diversion Project (YRDP) in Shanxi of China. The results indicated that twodimensional DCA ordination diagram could better reflect the water use condition of the dominant species under a transition from mesophytes to xerophytes. As compared with other species, Setaria viridis and Salsola collina had a larger niche breadth, showing their stronger adaptability to xeric and heavy disturbance environments, while Bromus inermis had a smaller niche breadth, indicating its poor adaptability to severe disturbance habitat. Therefore, Shannon index could better reflect the distribution characteristics of plants in natural recovery community. The niche breadth index of 33 dominant populations had a significant positive correlation with the frequency of these populations (r=0.995, P<0.01), suggesting that the greater the species frequency, the higher the Shannon index. The Pianka’s overlap index between S. komarovii and Agriophyllum squarrosum was the largest, with a similar niche breadth due to the resembled pattern of using environmental resources. However, the Pianka’s overlap index among Thymus mongolicus, S. viridis, and Convolvulus arbensis was lower because the ecological characteristics of these species were obviously different.

Key words: dominant species., MaxEnt model, potential distribution