乌鲁木齐土地利用碳排放强度时空演变研究

CARBON INTENSITY OF LAND USE IN WULUMUQI CITY BASED ON SPATIAL-TEMPORAL EVOLUTION

[目的]土地利用二氧化碳排放强度是土地低碳利用的重要指标,对其时空调控是协同促进城市二氧化碳排放总量达峰的重要路径。[方法]文章研究基于乌鲁木齐市2005年和2012年1km高空间分辨率排放网格数据(CHRED)和土地利用矢量数据,采用GIS空间分析法,探讨乌鲁木齐市7个城区土地利用二氧化碳排放强度的时空演变特征。[结果](1)从时间上看,乌鲁木齐市7个城区的土地利用变化整体表现为“5增2减”的现象;二氧化碳排放总量从3431.49万t上升到5147.96万t,其中以城镇村及工矿用地二氧化碳排放增长最大,由2005年的2885.15万t增加到2012年的4139.15万t。(2)从空间上来看,城市向北部和东南部扩展明显,未利用地和耕地迅速减少,城市扩展区的二氧化碳排放量有明显增加;中心城区和城市扩展区二氧化碳排放强度上升最快。(3)从土地利用转移上看,土地利用结构的变化明显,整体呈现草地、耕地和未利用地向城镇村及工矿用地、交通用地、园林地和水域等类型转移。草地、耕地和未利用地向城镇村及工矿用地转移导致的碳排放强度增长最显著,均超过700万t/万hm2。[结论]绿洲城市不同的土地利用类型二氧化碳排放强度时空差异较为显著,其中城镇村及工矿用地扩张是导致二氧化碳排放增长的主要原因之一。因此,合理控制绿洲城市扩张规模,优化城市用地布局,建立土地利用二氧化碳排放强度核算体系与综合调控政策,将是促进低碳城市建设的重要路径。

Carbon intensity of land use is an important index of low-carbon land use,the spatial-temporal evaluation of which is also a key pathway for reaching the carbon emissions peak of city.Based on the high spatial resolution emission grid data of 1km(CHRED)and land use vector data of Urumqi in 2005 and 2012,this paper made a spatial-temporal research on the carbon intensity of land use of seven districts in Urumqi by using spatial analysis of GIS.The results were shown as follows.Firstly,from the view of time,the carbon intensity of seven districts′land use showed a change of"five increases and two decreases".In general,carbon emissions of land use increased from 34.31 Mt in 2005 to 51.48 Mt in 2012 and that of urban land and industrial and mining land contribute most to this growth which raised from 28.85Mt to 41.39Mt over the same period.Secondly,from the perspective of space,there was an obvious expansion of the city to the north and southeast.The area of unused land and farmland rapidly decreased.While carbon intensity of Urumqi′s central and expansion areas rose fastest.Finally,from the view of land transformation,the grassland,farmland and unused land transformed to urban land,industrial and mining land,transportation land,garden land and water area.The transformation to urban land and industrial and mining land contributed an increase of carbon intensity by more than 700 t/hm2.There is significant differences of spatial-temporal carbon intensity of different types of land use in oasis city.The expansion of urban land and industrial and mining land is a main factor for carbon emissions growth.Therefore,it will be necessary pathways for the construction of low-carbon city such as controlling the scale of oasis city expansion,optimizing the layout of urban land and establishing the accounting system and comprehensive regulation policy of carbon dioxide intensity of land use.