Influence of pine wood nematode invasion on pine community function in Pinghu region of Zhejiang Province, eastern China.

Based on setting plots and measuring each tree method，several functional indices, including the increment (rate) in DBH and stand volume, biomass，etc., were investigated in the damaged stands with various proportions of Pinus massoniana and P. thunbergii and with different damage degrees. The results indicated that the forest ecosystem resistance against pine wood nematode (PWN) increased with the decrease of pines proportion based on the results of increment(rate) in DBH and stand volume. In this research，the resistance kept highest when a mixture proportion of 50% appeared. Besides，PWN changed the corresponding relation(pure stands＞7 conifer 3 broadleaf＞6 conifer 4 broadleaf＞5 conifer 5 broadleaf) of increment in DBH and stand volume among the P. thunbergii mixed stands when without PWN in，but the P. massoniana stands had no this phenomenon. For the increment rate of DBH and stand volume, significant changes were found in P. thunbergii forest after the invasion of PWN, indicating that the resistance of pure P. thunbergii forest was higher than that of P. massoniana. The invasion of PWN accelerates the succession advancement from pure stands to mixed stands，and then to the broadleaved evergreen forests.