劳动力价格上涨对商品林林种结构的影响及其约束研究

Research on the influence and constraint of rising labor price on the species structure of commercial forests

林种结构优化关系到国家生态安全与木材安全,是推进“双碳”目标实现的重要内容。基于1995—2018年中国30个省份的面板数据,在考虑要素相对价格与产品相对市场容量的约束下,采用门限回归模型实证分析了劳动力价格上涨对商品林林种结构的影响。结果表明:(1)劳动力价格上涨对商品林林种结构的影响显著受到要素相对价格或产品相对市场容量的约束,其约束具有门限效应。(2)要素相对价格和产品相对市场容量的约束均为单一门限,当两项约束均低于其门限值时,劳动力价格上涨均会诱使用材林种植扩张,而仅当产品相对市场容量高于其门限时,劳动力价格上涨会诱使经济林种植扩张;(3)在东部、集体林区和低山丘陵林区,要素相对价格与产品相对市场容量的约束均为双重门限,且仅当两项约束分别高于其第一门限值而低于其第二门限值时,劳动力价格上涨会诱使用材林种植扩张;在西部地区两约束均为单一门限,且仅当两项约束均低于其门限时,劳动力价格上会涨诱使用材林种植扩张。

The optimization of forest species structure is related to national ecological security and timber security and timber security,and is an important part of promoting the realization of the“dual carbon”goal.Based on the panel data of 30 provinces in China from 1995 to 2018,and considering the constraints of relative prices of factors and relative market capacity of products,a threshold regression model was used to empirically analyze the impact of rising labor prices on the structure of commercial forests.Results showed that:①The impact of rising labor prices on the species structure of commercial forests was significantly constrained by the relative price of factors or the relative market capacity of products,which had a threshold effect.②The constraints on the relative price of factors and the relative market capacity of products were both single thresholds.On the whole,when the two constraints were lower than their thresholds,labor price increases would induce the expansion of timber forest planting,and only when the relative market capacity of economic forest products was higher than its threshold,labor price increases would induce economic forest planting expansion.③The relative prices of factors and relative market capacity of products both presented double thresholds in the East,collective forest areas and low-mountain hilly forest areas only when the two constraints are higher than its first threshold and lower than its rising labor prices second threshold,would induce the expansion of timber forest planting.In the western region,the two constraints both presented a single threshold,and only when the two constraints were below their rising,threshold labor prices would induce the expansion of timber forest planting.