【摘要】 探究草地生态系统碳储量及其驱动因素对实现双碳目标具有重要意义，藏北高原作为我国重要的草地生态系统，其碳储量现状，空间格局以及驱动因素仍存在很大的争议。本文基于藏北高原150个实测样点数据，通过克里金插值和统计方法，评估分析了藏北高原草地生态系统的地上生物量碳密度、地下30 cm深度根系碳密度和土壤碳密度及其空间分布，以及各碳库的主要影响因素。结果表明：藏北高原地上生物量碳密度平均为0.038 kg C m^-2，地下生物量碳密度平均为0.284 kg C m^-2，土壤碳密度值最大，平均为7.445 kg C m^-2。藏北高原草地生态系统总碳储量约为4.08 Pg C，其中植被碳库0.58 Pg C（包括地上生物量和地下生物量），土壤碳库2.58 Pg C （其余分布在裸地中），碳储量分布格局呈现出从东南向西北递减趋势。植被碳库0.58 Pg C（包括地上生物量和地下生物量），约占青藏高原植被碳库的28.29%；土壤碳库2.58 Pg C，约占青藏高原土壤碳库的26.60%。降水、温度和土壤质地均影响生态系统碳储量，其中降水作用最显著，三因素结合对地上生物量碳密度解释率高达86.47%，藏北高原草地生态系统地上碳库最易受到气候因素调控，地下和土壤碳储量的空间格局机理更为复杂。本文研究结果可为藏北高原固碳能力评估提供基础资料。更多还原

【Abstract】 The investigation of carbon storage in ecosystems and its driving factors is crucial for understanding carbon cycling and achieving the goal of carbon neutrality.The grassland in the Northern Tibetan Plateau is an important grassland ecosystem in China,although the accurate estimation of its carbon stock and our knowledge of its spatial patterns and driving factors in the Northern Tibetan Plateau remain unclear due to insufficient field investigations.In this study,a dataset of 150 measured sample points on the Northern Tibetan Plateau,kriging interpolation and statistical methods were used to estimate the densities of aboveground biomass carbon,belowground root carbon and soil organic carbon at a soil depth of 30 cm,as well as to explore the spatial distribution and the main influencing factors of each carbon pool.The average carbon densities were 0.038 kg C m^-2 in aboveground biomass,0.284 kg C m^-2 in belowground biomass,and 7.445 kg C m^-2 in the soil.The soil organic carbon accounted for 95.85%of the grassland carbon density.The total carbon storage of the grassland ecosystem in the Northern Tibetan Plateau was about 4.08 Pg C,with a decreasing trend from southeast to northwest.Of the total,the organic carbon stocks of vegetation and soil were 0.58 Pg C （including the aboveground and belowground biomass） and 2.58 Pg C,accounting for 28.29% of the total vegetation carbon and 26.60%of the total soil carbon,respectively,on the Tibetan Plateau,with the remainder stored in the bare land.While the precipitation,temperature and soil texture all affected the ecosystem carbon storage,precipitation played the most significant role and the combination of these three factors explained up to 86.47%of the aboveground carbon density.The aboveground carbon pools in grassland ecosystems of the Northern Tibetan Plateau were most sensitive to climatic factors,while the spatial patterns of belowground and soil carbon storage were more complex.This study provides a spatially accurate assessment of the carbon storage in the grasslands on the Northern Tibetan Plateau.更多还原