天然次生林考虑伐后环境损失的多目标决策评价

Comprehensive Evaluation of Natural Secondary Forest Cut 10 Years Later Based on Multi-object Decision Model

山地森林采伐应注重经济、生态和社会效益的有机结合已成为共识。通过选取纯收益、土壤持水价值变化量、凋落物持水价值变化量、土壤养分价值变化量、凋落物养分价值变化量、固碳价值变化量和制氧价值变化量等7个效益指标,运用多目标决策分析方法,定量分析天然次生林5种不同强度(弱度13.0%、中度29.1%、强度45.8%、极强度67.1%和皆伐)采伐作业10a后的经济和生态效益评价值以及它们的综合效益评价值。结果表明:随着采伐强度的增大,经济效益评价值增大,而生态效益评价值则下降,皆伐的经济效益评价值最大,为0.300,而其生态效益评价值最小,为0.070;弱度择伐的经济效益评价值最小,为0.030,而生态效益最大,为0.670;中度择伐的综合效益评价值最大,为0.713,皆伐的综合效益评价值最小,为0.370。因此,类似试验条件的林区应推行低强度(弱度或中度)择伐经营方式,以实现天然次生林可持续经营。

It has been known that the economic,ecological and social benefits should be taken into account during forest harvesting.The economic and ecological comprehensive benefits of five different intensity cutting operations（low intensity 13.0%,middle intensity 29.1%,high intensity 45.8%,over-high intensity 67.1% and clear cutting）of natural secondary forest 10 years after cutting are analyzed by multi-object decision according to seven benefit indexes,which are net-income,changing retention of saturated water value of soil and litter,changing retention of nutrient content value of soil and litter,changing retention of firmed carbon and made oxygen value.The results show that with the cutting intensity increased,the economic beneficial value was increased,but the ecological beneficial value was decreased.The economic beneficial value of clear cutting is largest,which works out at 0.300 while the ecological beneficial value of clear cutting is the worst,with its value being 0.070;the economic beneficial value of selective cutting is smallest,which works out at 0.030 while the ecological beneficial value of selective cutting is the optimal version,with value 0.670.The middle intensity selective cutting is the optimal version,which works out at 0.713 while the clear cutting is the worst,with its value being 0.370.So,the similar experimental condition areas should pursue the low or middle intensity selective cutting in order to realize the natural secondary forest sustainable management.