马尾松林火灾后生态效益损失动态评估

依据林分生长规律和经营模式,建立生态效益损失动态评估模型;对广州从化30年生马尾松林分森林火灾后,经过人工更新的林分45年内所产生的生态效益进行模拟,认为该林分若未遭受森林火灾,封山育林模式的生态效益最大;灾后更新林分需要30年才能恢复相当于灾前林分的生态效益;其间生态效益的损失量为传统静态定量估算的25.92倍.如果林分采取30年轮伐的经营模式,在第19年左右时轮伐林分和灾后更新林分所产生的生态效益平衡;此后人工更新林分的生态效益渐高,而受灾林分经人工更新后第17年时的生态效益近似于轮伐林分的稳定值.轮伐型所带来的总效益在前6年大于封育型的总效益,但第7年以后其总效益开始小于封育型经营模式的生态效益.

Dynamic Estimating of the Loss of Ecological Benefits after Forest Fire in Pinus massoniana Forests

According to growth period of forest stand and management pattern, the paper advances the dynamic model to estimate the loss of ecological benefits after the estimating indices have been ascertained to estimate the loss of ecological benefits after forest fire. For 30-year-old Pinus massoniana stand, which has been man-regenerated 45 years after fire, its ecological benefits are simulated, the result show that the optimal decision of forest conservation can bring maximal ecological benefits and only the 30-year-man-forestation stand after fire can get the ecological benefits of non-stricken stand and the total loss of ecological benefits is 25.92 times as much as that counted by traditional method. On the other hand, if the alternating lumber mode about 30-year-felling-cycle is taken, at the 19 th year the ecological benefits is comparative that of man-forestation stand, henceforth the latter can be much more provided with the ecological benefits, and at the 17 th year, the total ecological benefits coming from man-forestation stand is equivalent to the steady comparatively value produced by alternating lumber stand which has been over one rotation. The total benefits of alternate cutting mode will be more than the total ecological benefits of forest reservation in the early six years; but this situation will be changed after the seventh year.