Impact of Invasion of Bursaphelenchus xylophilus on Carbon Storage of Pinus massoniana Pure Forests

As an alien invasive species, Bursaphelenchus xylophlius has a great impact on the biodiversity and carbon sequestration capacity of Pinus massoniana forests. In this study, P. massoniana forests infected by B. xylophlius for 4 years and 8 years were chosen as the research objects, and uninfected P. massoniana forest and evergreen broad-leaved forest were used as control groups, aiming to explore the change pattern of carbon storage of such P. massoniana forests. Results are presented as follows: the carbon storage of uninfected P. massoniana forests was the largest, surpassing the remaining （P<0.05）, followed by that of the evergreen broad-leaved forest which was much greater than those of 4-year and 8-year infected P. massoniana forests. The annual increment of carbon storage for the uninfected P. massoniana forest was the largest, ranking above the remaining obviously （P<0.05）, followed successively by those of the 4-year infected P. massoniana forest and the evergreen broad-leaved forest with no significant difference. The annual increment of the 8-year infected P. massoniana forest was the smallest, which is significantly less than the others. The relative growth rate of carbon storage of the 8-year infected P. massoniana forest exceeded the remaining obviously （P<0.05）, which was higher than those of the 4-year infected P. massoniana forest, the uninfected and evergreen broad-leaved forests successively. Simultaneously, the invasion of B. xylophilus would result in the distribution homogenization of carbon storage for species in P. massoniana forests, the accelerative succession to evergreen broad-leaved forest and the augmentation of the relative growth rate of carbon storage probably by the increase of soil total nitrogen content.