Impacts of land cover change on plant and bird species diversity in Hainan Island,China

１ＩｎｔｒｏｄｕｃｔｉｏｎＬａｎｄｃｏｖｅｒｃｈａｎｇｅｈａｓａｎｉｎｃｒｅａｓｉｎｇｉｍｐａｃｔｏｎｆｏｒｅｓｔｅｃｏｓｙｓｔｅｍｓｗｏｒｌｄｗｉｄｅ．Ｔｈｅｄｅｓｔｒｕｃｔｉｏｎｏｆｎａｔｉｖｅｈａｂｉｔａｔｓｉｓｒｅｃｏｇｎｉｚｅｄａｓｏｎｅｏ...

Impacts of land cover change on plant and bird species diversity in Hainan Island,China *

Hainan Island, located at the southern end of China, has less than 0.4% of land area but contains 13% of plant and animal species in China. During the last four decades many primary forests have been converted to shrub land, grassland, and tree planation (e.g., eucalyptus forest). As a result, area of primary tropical forest has been reduced from 25.8% in the 1950s to 4% in the 1990s. To assess impacts of land conversion on plant and bird species diversity, a series of samples in primary forest and four types of converted lands were took. The land conversion had tremendously reduced both plant and bird species diversity. Specifically, plant species richness per site was 83.7 in primary forest, 28.3 in shrub land, 12.5 in grassland, 14.4 in eucalyptus forest, and 21.4 in Acacia forest. Bird species richness showed a similar trend: 22.0 in primary forest, 14.5 in shrub land, 2.5 in grassland, 4.9 in eucalyptus forest, and 9.0 in Acacia forest. The Shannon species diversity indices for plants in the five types of land cover were 3.69, 1.99, 0.97, 1.47 and 2.07, respectively. Similarly, the Shannon indices for bird species diversity were the highest in primary forest, and lowest in grassland, and intermediate in shrub land and eucalyptus forest.