森林采运作业过程碳排放分析

Carbon Emission in Forest Logging Operation Process

合理的森林采伐能开发利用森林资源,促进林木生长,但盲目采伐会导致生态环境的破坏。以生命周期评价法的B2B（business-to-business）模式为基础,采用过程分析法,核算森林采运过程各阶段的温室气体排放量。结果表明：采运过程中产生的碳排放约为7.530 6~11.659 8 kg/m3,约占其固碳能力的2.2%~5.7%;燃油消耗是最主要的碳排放源,CO2是其排放的最主要温室气体,碳排放量与集运材距离呈正相关;采伐段碳排放最少,仅0.573 6 kg/m3,索道集材、拖拉机集材排放分别是采伐段的1.04、1.72倍,运材段产生的排放量最多,当运材距离为40 km时,汽车运材和农用车运材排放量分别是采伐段的11.1和17.6倍;油锯采伐＋索道集材＋汽车运材为最优作业模式。研究结果可为森工作业的减排提供理论参考。

Rational harvesting can utilize forest resources and promote trees growth. But unreasonable logging will destroy the ecological environment. Based on B2B model of life cycle assessment,greenhouse emissions during every stage of logging were estimated using process analysis method. The results showed that the carbon emission of logging was about 7. 530 6 kg / m3- 11. 659 8 kg / m3, accounting for 2. 2%- 5. 7% of its carbon sequestration capacity. The major carbon emission source was fuel consumption and CO2 was the main greenhouse gas. Carbon emission was positively related to transportation distance. The least carbon emission appeared at the cutting stage,with only 0. 573 6 kg / m3. But the carbon emissions during cable logging and vehicle logging transportation were respectively as 1. 04 and 1. 72 times as much as that of cutting stage. The most carbon emission appeared in log transportation. When the transportation distance was 40km,the carbon emissions for motor vehicle and agricultural vehicle were 11. 1 and 17. 6 times as much as that at cutting stage. Therefore,the optimal operation model for logging was the combination of chain saw cutting,cable logging and motor vehicle transportation. The results can provide theoretical references for forest engineering to reduce carbon emissions.