土地整理过程中碳量损失与生态补偿优化设计

Carbon storage loss during land readjustment and optimization of ecological compensation

土地整理改变了项目区土地利用结构,打破了生态系统碳循环平衡。在土地整理实施的过程中以及实施以后一段时期,项目区生态系统碳蓄积量必然损失,从而使项目区农业生态系统由碳汇变成了碳源。以湖北省荆门市东宝区崔院村土地整理项目区为例,拟通过对生态系统碳蓄积量的估算,并采用线性规划的方法求算土地整理规划设计的最佳土地利用结构,从而实现对土地整理所引起的生态系统碳量损失进行补偿的目标。结果表明,为了实现土地整理的耕地面积最大化目标,通过采用线性规划的方法所得到的土地利用结构优化方案能够很好地满足规划设计所涉及的各类用地的面积以及生态系统的碳量平衡等约束条件。耕地面积增加量占总土地面积的11.94%实现了最大化目标,同时满足了道路系统和水利灌溉系统以及居民点等用地的需求,而人工林地的面积必须增加3.90 hm2,也就实现土地整理前后生态系统碳量的平衡。

Land readjustment could change the structure of land use, and destroy the balance of ecosystem carbon cycle. In the period and after a definite time of land readjustment, the carbon storage in agricultural ecosystem would be decreased, making the ecosystem turn from carbon sink to carbon source. Based on the estimation of the ecosystem carbon storage in Cuiyuan village of Jingmen City, and with a linear programming model, this paper approached the optimal structure of land use for the land readjustment in the study area, which could compensate the ecosystem carbon storage loss. The results showed that an increment of cultivated area to 11.96 % of the total area should be the maximization to meet the needs of building road system, irrigation system, and housing estate. To make the balance of ecosystem carbon cycle, artificial forest area should be increased by 3.90 hm^2.