基于造林成本法的林业碳汇成本收益影响因素分析

林业碳汇市场化进程缓慢,碳汇成本是关键影响因素之一.本文借鉴Benítez固碳模型,考虑土地利用的机会成本和木制品的碳释放成本,构建了基于造林成本法的林业碳汇成本模型,并对浙江省瑞安市20年期的湿地松碳汇造林项目进行实证分析.文中动态分析了轮伐期,木材价格,贴现率和劳动力价格等因素对碳汇成本收益的影响,结果表明:随着轮伐期的增加,湿地松碳汇成本先下降再上升,若考虑木材收益,20年期的碳汇成本为21.86元/t,可获得碳汇收益;若不考虑木材收益,其碳汇成本则为670.33元/t,高于国际和国内市场高位碳汇价格,将不能获得收益;此外,碳汇成本还与木材价格负相关,与贴现率和劳动力价格正相关,文中还分别分析了其保本点的木材价格,贴现率和劳动力价格.

Influencing factors analysis of forestry carbon sequestration cost-benefit based on afforestation cost methods

The process of marketization of forestry carbon sequestration is slow and one of the key influencing factors is the cost of carbon sequestration. This paper builds a model of forestry carbon sequestration costs based on afforestation cost methods referencing Benitez's model for carbon sequestration that considered the opportunity cost of land use and the carbon release cost of wood products. We then conducted an empirical analysis over 20 years of the slash pine afforestation of carbon sequestration project in Ruian city,Zhejiang,China and analyzed factors (e.g. rotation period,timber price,discount rate,and the price of labor)influencing the carbon sequestration cost. The results showed that increasing the rotation period resulted in the cost of slash pine carbon sequestration declining and then rising. When the timber value was taken into account the lowest cost of carbon sequestration of 20 years slash pine was 21.86 CNY/t. When the timber value was not considered,its lowest carbon sequestration cost was 670.33 CNY/t,which was higher than the carbon price in both international and domestic carbon markets and would not receive benefits from carbon sequestration. We also found that costs of carbon sequestration and the timber price were negatively correlated,while the discount rate and labor price were positively correlated. We focus on the break-even point of timber price,discount rate and labor price of carbon sequestration afforestation,and the critical value was 660 CNY/m³,5.44% and 155 CNY per day,respectively,in the international carbon market; in the domestic carbon market these values were 900CNY/m³,6.38% and 116 CNY per day,respectively.