Study of Bird Diversity on the North Slope of Changbai Mountain II Composition of Bird Community Varies with Different Altitude Gradients

The investigation of 84 bird species in 9 plant communities in 25 plots of 5 botany belts indicated that the variety of bird species in Korean pine mixed with broadleaf tree species belt in secondary broadleaf-conifer mixed forests reaches the maximum,48 in amount,accounting for 57.14% out of the total.The analysis of 6 bird groups indicated that with the increase of altitude,the phenomenon of bird species being replaced by other species from the same group is obvious.The bird species diversity and bird abundance decrease with the increase of altitude,but the evenness is similar at different altitudes.Both of the indexes of bird diversity and bird abundance are different in different forest belts and botany communities,and they are the highest in Korean pine mixed with broadleaf tree species belt of secondary broadleaf-conifer mixed forests(index of bird diversity is 2.73 and that of abundance is 4.79) and in Trembling Aspen-Birch mixed belt of conifer forests(index of bird diversity is 2.41 and that of abundance is 3.73).