黑河绿洲区耕作土壤有机碳及其活性和非活性组分固碳潜力研究

Research on Cultivated Soil Carbon Sequestration Potential in the Heihe Oasis

土壤有机碳固碳潜力研究是陆地生态系统碳循环中的前沿领域，可为区域农业碳管理和温室气体减排提供依据。以黑河绿洲区水田为研究对象，采用实地土壤样品采集、室内指标分析和模型模拟方法，研究了表层0-20cm土壤不同粒径与土壤TOC、AOC、NOC之间的关系，在此基础上建立了土壤TOc、Aoc和NOC物理化学固碳潜力模型并估算固碳潜力。结果显示绿洲农田土壤存在较大的固碳空间，TOC、AOC、NOC固碳潜力平均值分别为0．75％、0．14％、0．56％。并以中游绿洲水田为例，计算了土壤TOC、AOC、NOC碳密度、碳储量及其潜力，其中水田TOC、AOC、NOC碳密度的潜力分别为0．18、O．03、0．15g／cm^2，水田中TOC、AOC、NOC碳储量的潜力分别为7．12Tg、1．13Tg、5．79Tg。分析发现水田中NOC的碳密度和碳储量提升的空间明显高于AOC，说明NOC的提高是TOC固碳的关键。

Research on soil organic carbon sequestration potential is the frontiers of carbon cycle in terrestrial ecosystem; it can provide the basis for agricultural carbon management and greenhouse gas reduction. The relationships between different soil particle sizes and total organic carbon （TOC）, active organic carbon （AOC）, nonactive organic carbon （NOC） were researched in the Heihe oasis using field samples gathered, laboratory analysis and model simulation methods, then physical and chemical carbon sequestration potential models of TOC, AOC and NOC are built and the carbon sequestration are estimated. Results show paddy field soil has great carbon sequestration space, carbon content potential of TOC, AOC and NOC is 0.75%, 0.14% and 0.56%, respectively. In the middle of Heihe oasis, carbon density, storage and their potential of TOC, AOC and NOC in paddy field are calculated, carbon density potential of TOC, AOC and NOC is 0.18 g/cm2, 0.03＇g/cm2 and 0.15 g/cm2, carbon storage of TOC, AOC and NOC is 7.12 Tg, 1.13 Tg and 5.79 Tg, respectively. The results showed NOC density and storage potential in paddy fields was significantly higher than the AOC, it indicated the improvement of NOC was the key of carbon sequestration.