Remote sensing assessment of carbon balance vis-a-vis energy-related emissions and vegetation sequestration in a typical arid region of China from 2001 to 2020

Since 2000, the Western Development Strategy and warming-humidification of Northwest China have led to notable changes in Xinjiang’s carbon emissions and sequestration. Understanding the regional carbon budget is key to sustainable development. This study employed fused nighttime light data and statistical records to perform piecewise function fitting, effectively reflecting long-term trends in energy-related carbon emissions. Meanwhile, NDVI, land use, and meteorological data were integrated into the CASA model to accurately estimate the variations in vegetation carbon sequestration. Accordingly, we employed multi-source remote sensing data to model carbon emissions and sequestration, focusing on carbon balance changes in Xinjiang and its main cities with varying levels of economic development. Results show: (1) Emissions rose significantly, surpassing sequestration in 2012; (2) Emissions showed spatial shifts southward, while sequestration remained stable but expanded in area; (3) Regional rankings revealed significant spatial differentiation in carbon emissions and sequestration, with consistently rising emissions and limited sequestration gains at the city level, leading to a dominant carbon expenditure profile; (4) Precipitation-driven climate factors positively influenced sequestration, while GDP-driven human activities significantly increased both emissions and sequestration. This study offers a reliable spatial carbon balance estimation method to support regional carbon peak and neutrality goals.

自2000年以来，中国西部大开发战略与西北暖湿化进程共同推动新疆地区碳排放（carbon emissions）与碳固存（carbon sequestration）发生显著变化。明晰区域碳收支是实现可持续发展的核心要义。
本研究融合夜光数据与统计资料开展分段函数拟合，有效刻画了能源相关碳排放的长期演变趋势。与此同时，本研究将归一化植被指数（NDVI, Normalized Difference Vegetation Index）、土地利用与气象数据整合至CASA模型中，精准估算了植被碳固存的动态变化。
据此，本研究借助多源遥感数据构建碳排放与碳固存模拟模型，重点分析了新疆全区及不同经济发展水平下主要城市的碳平衡变化特征。
研究结果显示：
（1）碳排放显著增长，并于2012年超过碳固存水平；
（2）碳排放呈现空间南移趋势，而碳固存整体保持稳定但面积有所扩张；
（3）区域碳收支层级分析表明，碳排放与碳固存存在显著空间分异特征；城市尺度下，碳排放持续攀升，而碳固存增幅有限，整体呈现以碳支出为主的格局；
（4）降水驱动的气候因子对碳固存产生正向影响，而GDP驱动的人类活动则显著提升了碳排放与碳固存水平。
本研究提供了一种可靠的空间碳平衡估算方法，可为区域碳达峰与碳中和目标的实现提供支撑。