渭河流域生态系统生产力和土壤有机碳的时空变化特征

The Spatiotemporal Dynamics of Ecosystem Productivity and Soil Organic Carbon in the Weihe River Basin

增强陆地生态系统碳汇功能和提高碳储量是碳达峰与碳中和的关键环节。植被和土壤是陆地生态系统中碳汇能力最强、碳储量最大的两个部分。本文以黄土高原典型流域渭河流域为研究对象,结合生物地球化学综合模拟系统(GEMS)和侵蚀沉积碳模型(EDCM),对渭河流域1992—2021年净初级生产力(NPP)和土壤有机碳(SOC)的时空动态进行研究。结果表明,渭河流域NPP呈东南高、西北低的分布格局,总体呈增加趋势;流域关键作物高产区主要集中在陕西关中平原,其中长安县和鄠邑县产量最高;流域SOC整体呈增加趋势,平均增长率约为23g·m^(-2)·a^(-1),流域东部SOC低值区增长速率较大。本研究定量评估了渭河流域植被和土壤碳汇潜力,可为区域固碳减排提供关键数据支撑和科学参考。

Enhancing the carbon sink capacity and carbon storage of terrestrial ecosystems is the key to achieving the commitment of carbon peaking and carbon neutrality.Vegetation and soil are the two components with the strongest carbon sink capacity and the largest organic carbon storage in terrestrial ecosystems,respectively.Therefore,we used the General Ensemble Biogeochemical Modeling System(GEMS)and the Erosion Deposition Carbon Model(EDCM)to explore the spatiotemporal dynamics of net primary productivity(NPP)and soil organic carbon(SOC)from 1992 to 2021 in the Weihe River Basin(WRB),a typical watershed in the Loess Plateau.The results showed that:NPP increased during the study period,showing a gradient pattern from southeast to northwest.The high-yield areas of key crops in the WRB were mainly distributed in the GuanZhong Plain,with Chang′an and Huyi Counties having the highest yields.SOC increased with an average rate of 23g·m^(-2)·a^(-1),with a higher growth rate in the low SOC regions locating in the east of the WRB.This study quantitatively evaluated the potential capacity of vegetation and soil carbon sinks in the WRB,and provided data support and scientific reference for regional carbon sinks and emission reduction.