以低碳为目标的海东市土地利用结构优化方案

以低碳为目标的土地利用结构优化对区域和全球的碳循环具有重要意义。该文以海东市为例探讨了青海高原东部农业区低碳导向的土地利用结构优化方案。首先计算了海东市主要土地利用类型的碳密度和碳排放系数,然后以最大化碳储量和最小化碳排放量作为目标函数,运用线性规划方法构建了土地利用结构优化模型,获得了土地利用结构优化方案。通过与土地规划方案的对比发现,基于碳储量最大化的优化方案最佳。在该方案下,到2020年海东碳储量达14 171.68万t,碳排放量为217.65万t,比规划方案的碳储量增加了7.77万t,同时减少了31.98万t的碳排放,可见以增加碳储量和减少碳排放为目的的优化方案,对区域固碳作用明显。该结论能为相关部门进行土地利用规划及其调整提供了有效支持。

Optimization of land use structure for low-carbon targets in Haidong City,Qinghai Plateau

Optimizing land use structure for low-carbon targets is important to regional and global carbon cycle research. Here,we investigated low-carbon oriented land use structure optimization for Haidong in Qinghai,China,located in the eastern part of the Qinghai Plateau. Carbon storage and carbon emission factors for each land use type in Haidong were calculated based on local carbon mechanisms. Methods for calculating carbon storage and carbon emission estimation have been established systematically. Land use quantitative structure optimization models aimed at maximum carbon storage and minimum carbon emissions were constructed using linear programming methods. Two optimized schemes were obtained using land use quantitative structure optimization models. By comparing land use planning schemes with that of carbon storage maximizing and carbon emission minimizing we found that although the carbon emission minimizing scheme in Haidong is capable of bringing carbon emissions to the lowest level in 2020,the corresponding carbon accumulation is much less than that of the land use planning scheme. The carbon storage maximizing scheme can increase carbon storage in Haidong to 141.71×10⁶t in 2020,which is 77.7×10³t higher than the land use planning scheme. However,this maximizing scheme can decrease carbon emissions to 2.17×10⁶t,which is 319.8×10³t lower than for land use planning. In comparing the land use programming scheme,the main advantages of the carbon storage maximizing scheme would be that it increases the rate of increasing forestry and dampens the expansion rate of construction land. Therefore,low-carbon oriented land use structure optimization is good support for government land use planning and adjustment.