THE ECOLOGICAL DISTRIBUTION CHARACTERISTICS OF SOME GENERA AND SPECIES OF VAM FUNGI IN NORTHERN CHINA
我国北方VA菌根真菌某些属和种的生态分布

The work was carried out in the area of 1,790,000 Sq. Km. of northern China. The results were as follows: The distribution of some genera and species of VAMF shows regional difference. Glomus is dominant genus in the area. The distribution of some genera and species of VAMF has relation to soil pH, the content of soil organic matter(OM), and elevation of collecting sites. Within pH 5-9.5 the greater of soil alkalinity the more Glomus were found, the greater of soil acidity the more Acaulospora were observed. There was no Scutellospora in soil whose pH was greater than 9. Less Glomus existed in soil whose content of OM was greater than 10 %, but Glomus sp.9 mainly occurred in soil which was rich in OM. Some Acaulospora species showed certain selectivity to the content of OM. Generally more Scutellospora could be isolated from soil with high content of OM. When elevation was over 3000M, Glomus and Acaulospora decreased rapidly, and Scutellospora was never found. Some species in Glomus were more sensitive to elevation. Six species were found in 21 soil samples which irrigated with sewage for more than 20 years in Beijing. G. mosseae was the most common species either in sewage irrigation soil or in investigated area. VAM fungi are divided into euryeco-logical type and stenoecological type according to different adaptability and selectivity to environment and reginity.