Taking four grassland types in five forest areas in the Habahe region of the Altai Mountains as the research object

the change characteristics of species diversity of each grassland type in the five forest areas in Habahe region were analyzed. The regression analysis

correlation analysis

and VOR index were used to explore the influencing factors of species composition and diversity of different grassland types

and to evaluate the health status of their grassland ecosystems. The results showed that: (1) Among the differe

nt grassland types

the community similarity coefficient between desert steppe and mountain meadow steppe and mountain meadow steppe ranged from 0 to 0.25

and the heterogeneity was the large. The similarity coefficient between mountain steppe and mountain meadow steppe ranges from 0.50 to 0.75

with the small heterogeneity. (2) Among the four grassland types

the R

2

between the Margalef index

Simpson index

and Shannon-Wiener index of each grassland type was less than 0.75

and the quadratic term fitting showed a large difference

and the coverage and biomass were extremely significant correlated (p

<

0.01). (3) The relationship between altitude and biomass was poor

and R

2

was less than 0.40. Only the altitude and biomass of mountain meadow were significantly correlated (p

<

0.01)

and the rest were not correlated. (4) Overall

the biomass of the five forest areas in September was less than that in June

but the biomass of the mountain steppe and the mountain meadow steppe in the Baihaba forest area in June was less than that in September

and the biomass of the desert steppe in the Hujierte forest area in June was less than that in September. (5) The average biomass of the five forest areas was fitted with the VOR index

and R

2

ranged from 0.118 to 0.712. The health level of grassland ecosystem in 5 forest areas was Naren (0.914)

>

Baihaba (0.863)

>

Tielieke (0.848)

>

Hujierte (0.845)

>

Qibaqilieke (0.827). The results provide an important basis for understanding the health status of grassland ecosystem in the Habahe region

and are of great significance for understanding the spatial distribution pattern and rational utilization of different grassland resources in the Habahe region of the Altai Mountains.