Vegetation restoration and regeneration of the secondary disaster area in Beichuan after the May 12, 2008 earthquake
In Beichuan, a severely afflicted area from the May 12, 2008 earthquake, vegetation was severely damaged with numerous secondary disasters. This study aimed to understand recovery of the natural vegetation for different types of disasters of the May 12, 2008 earthquake. Five different types of disasters in Beichuan County were selected, including avalanches(B1), rock fall(B2), debris flow(B3), landslides(B4), and bar-rier lakes(B5)with one intact forest(ck). A total of 180 quadrats of five different types of disasters in Be-ichuan, were selected to conduct vegetation investigation, adopting important value, Shannon-Wiener diversity index, Margalef richness index, Hurlbert evenness index and other indexes to be used to evaluate the plant community species composition, structure, species diversity, and similarity of species. Results indicated that (1)secondary disasters had a simple plant community structure, where Compositae and Gramineae herbs were dominant vegetation types, with the number of species being B4>ck>B5>B2 = B3>B1. (2)In the sec-ondary disaster area, the dominant species of the tree layer was Alnus cremastogyne, the dominant species of the shrub layer was Debregeasia orientalis,and the dominant species of the herb layer were Miscanthus floridu-lus, Senecio scandens, and other Compositae plants.(3)For species similarity, the secondary disaster area and intact forest land had strong differences with species similarity coefficients being B4(0.19)>B5(0.13)>B2 (0.10)>B3(0.06)>B1(0.02). However, many similarities between different secondary disaster areas were found with similarity coefficients between B2,B3,B4,and B5 of about 0.28.In conclusion,the natural recovery and renewal were slower in the five different types of disasters in Beichuan.
国家科技期刊平台
NSTL
万方数据
维普
