A Study On Community Characteristics And Ecological Adaptability Of Allium Polyrhizumin Inner Mongolia Plateau

We investigated community in Wulanchabu League, Xilin gol League and Hulunbeir League during 2010 to 2013 and did some experiments during March to October in 2014, and put Allium polyrhizum as research object by analyzing community characters, soil salinity characters, conditions of seed germination, germination salt resistance and response under salt stress. We get the following conclusions:(1) Form. Allium polyrhizum includes 91 species belonging to 58 genera,20 families, and they are all angiosperms. Among them there are 4 families,16 genera, 21 species in Gramineae. Others include 16 families,42 genera,70 species. The types of life form are mainly perennial herb, accounting for 51.6%, others are one or biennial herbs, subshrub and small half-shrub and shrub, accounting for 35.13%,11%, 2.19%. Xerophyte is the main type of water ecotype, accounting for 73.62%. The flora of Eurasia steppe-Asia is in dominant position, accounting for 45.07%. Holarctic element is one of the most in temperate element, accounting for 18.68%. And it is also influenced by the flora of the ancient Mediterranean and the east Asiatic. The Form. Allium polyrhizum divides into five association groups which include Ⅰ.Ass. Allium polyrhizum—Stipa krylovii Ⅱ. Ass. Allium polyrhizum-Ajania achilleoides. Ⅲ. Ass. Allium polyrhizum-Cleistogenes songorica Ⅳ. Ass. Allium polyrhizum-Convolvulus ammannii Ⅴ. Ass. Allium polyrhizum-.Cleistogenes songorica.(2) Allium polyrhizum grow in Mild salinization soil rich in plaster, significant correlation exist between 0-10cm,10-20cm the content of salty and community richness, Shannon-Wiener Index and Simpson Index. And the best fitting curve is trinomial. Significant correlation doesn’t exist between the layers of soil salt content and community evenness. The highest content of salty is in 20-30cm, and it doesn’t exist significant correlation with other indexes.(3) The best germination condition of Allium polyrhizum is in 20℃ constant temperature and 24 hours of darkness, and it doesn’t germinate over 25℃.(4) Salt stress can inhibit the germination of Allium polyrhizum, and the inhibition will increases with the concentration of salt. The germs have greater inhibition than the radicles in salty solution. The salt tolerance threshold of seed germination period is less than 88.13mmol/L.(5) Salt stress can inhibit the growing of Allium polyrhizum and Stipa krylovii. Different physiological indexes of Stipa krylovii are more tolerant of salt stress than Allium polyrhizum. We analyze various indexes of Allium polyrhizum and Stipa krylovii by subject function and find that the salt tolerance of Stipa krylovii in seedling is stronger than that of Allium polyrhizum.