碳氧平衡法可通过比较人类活动引起的释碳耗氧量与生态用地的固碳释氧能力之间的平衡关系来测算碳氧平衡标准下生态用地需求量。以武汉市为例,遵循"环境友好、资源节约"的两型社会建设原则构建了土地利用综合效益最优的多目标函数,以2013年为基期年且2020年为目标年,探索了碳氧平衡约束条件下武汉市土地利用结构的优化方向。研究结果表明:土地利用结构优化后2020年较2013年增加了40 908hm2标准生态用地,产生431亿元的综合效益,年固碳能力和释氧能力分别达到532.03万t和1 418.33万t,分别占武汉市释碳耗氧量的43.25%和30.29%,能完成区域内的固碳任务且有盈余,但不能实现区域内的氧平衡。研究结果表明仅通过增加生态用地来维持碳氧平衡将难以为继,长期来看,必须转变发展方式来维持碳氧平衡状态。
With carbon-oxygen balance theory,ecological land demand with carbon-oxygen balance standards can be estimated by comparing the carbon release and oxygen consumption induced by human activities and carbon sequestration and oxygen release capacity of ecological land.This paper takes Wuhan as an example,land use comprehensive benefits optimal objective function is set up following the twooriented society construction principles as "environmentally friendly,resource conservation," with 2013 as the base year and 2020 as the target year,the direction of land use structure optimization under carbonoxygen balance constraints in Wuhan is explored.The results indicate that compared with 2013,the standard ecological land in 2020 will increase by 40908 hectares after optimization of land use structure,there will generate overall efficiency of 43.1billion yuan carbon sequestration capacity and oxygen release capacity will reach 5.32 million tons and 14.18 million tons,accounting for 43.25% of carbon release and30.29% of oxygen consumption respectivelycarbon sequestration task can be completed and there is a surplus,but oxygen balance can’t be achieved within the region.It will be difficult to maintain carbon and oxygen balance only by increasing the ecological land,so development patterns must be transformed to hold the balance in the long term.