Study on flora in region of northern slope of Karlik Mountain-Naomao Lake Basin, East Tianshan Mountains.

The study area covering the Karlik Mountain and Naomao Lake Basin is located in the east Tianshan Mountains and in a zone between the Altay Mountains and the Tianshan Mountains separately.In the study area,there are 345 plant species in 188 genera and 47 families.These species are dominated by dicotyledons,most of which are the perennial herbaceous plants.This reflects that the species succession is in a younger evolution stage in this region.There are 11 dominant families,such as Gramineae,Compositae,Cyperaceae,Ranunculaceae and Caryophyllaceae,with several typical families including Gramineae,Chenopodiaceae and Polygonaceae,etc.,in the study area.The single-species families,few-species families,single-species genera and few-species genera constitue the main parts of the local floras.Compared with the ratio between the genera and the species in Xinjiang,the polarization degree of species in the genera is high in this region.Families and genera in the cosmopolitan floras are abundant in the study area,because only these families and genera can adapt to the severe environment well depending on their wide adaptive capacities.The areal types are various,the geographical elements of the genera are complex,and the floras are not only ancient but also young.In the flora composition,the warm-temperate elements with total number of 109 genera are dominant.Among the warm-temperate floras,the proportion of the north-temperate floras is the highest,the Mediterranean elements also take an important position in the local floras,but the proportion of other areal types is at the subordinate position.The areal types of species are dominated by the Central Asia flora component.There are 14 endemic species of Xinjiang in this region,and they account for 5.22% of the total.The main geographical composition of these genera is the temperate elements,and then the Mediterranean components.