Canonical correspondence analysis (CCA) is a direct sequencing method which can reflect the relationship among communities, distributions of species and environment factors in a simple way, and be used to study the relationship between the biology distribution and the environment factors effectively. It has been used in the biology and the ecological environment widely. In this paper, 49 surface sediment samples are collected to study the ecological distribution of extant ostracodes and their environmental implications for water bodies in south of northern Tibet in 2012. Total of 10 genera and extant ostracodes of 22 species are identified, among which, Limnocythere dubiosa, Ilyocypris bradyi and Candona candida are the common species with high occurrence frequency of 19, 13 and 9, respectively in Ali and Naqu regions, Tibet. CCA reveals a correlation coefficient of more than 80% between the extant ostracodes distribution and the eight environmental factors, suggesting that the distribution of many species is highly related to environmental changes. Among eight environmental factors, the conductivity, the pH value and the nitrite content are the most affective variables on the species occurrence. Eucypris rischtanica, Leucocythere dilitata, Cypricercus moguntiensis and Limnocytherellina kunlunensis have relatively strong adaptability to the water environment. The high occurrence frequency of Leucocythere postericosta, Limnocytherellina bispinosa and Candona houae corresponds to a high water conductivity and nitrite content, as the distribution of these species positively correlates with the water conductivity and the nitrite content, suggesting that the three species are good indicators for the water conductivity and the nitrite content. On the other hand, Ilyocypris bradyi and Candona candida are good indicators for the low conductivity. As for Limnocythere dubiosa, the most frequently occurred ostracode in Ali and Naqu regions, is a good indicator for the high pH value.

extant ostracodes  /  ecological distribution  /  canonical correspondence analysis  /  environmental factors  /  the south of northern Tibet