Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130024, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130024, China.
Sci Total Environ. 2021 Jun 25;775:145188. doi: 10.1016/j.scitotenv.2021.145188. Epub 2021 Feb 15.
Spartina alterniflora has rapidly expanded in coastal wetlands of China, and this would affect soil organic carbon (SOC) storage and stability. In the present work, the impacts of S. alterniflora colonization on SOC pool and stability was deciphered to better understand how alien species altered the carbon cycle in the Yellow River Delta (YRD). SOC contents were in the range of 1.29 g/kg-7.02 g/kg, of which wetlands covered by S. alterniflora increased with colonization time and exceed those in wetlands covered by native species after 7 years. Pyrolysis-gas chromatography/mass spectrometry analysis showed that aromatic moieties were predominant components of SOC, and there were remarkable increase trends of phenol and lignin compounds and decrease trend of aromatic moieties with S. alterniflora invasion time. SA had the highest microorganism biomass reflected by phospholipids fatty acid (PLFA) across different wetlands. Salinity had the largest negative effects while nutrients had the largest positive effects on the SOC pool. The proportion of decomposition-resistant compounds (including aromatics, lignin, and phenol) to total SOC was decreasing while the SOC pool was increasing with S. alterniflora invasion time. This study demonstrated that S. alterniflora invasion could promote the SOC pool but weaken its stability in the wetlands of the YRD.
互花米草在中国沿海湿地迅速扩张，这将影响土壤有机碳（SOC）的储存和稳定性。本研究旨在深入了解外来物种如何改变黄河三角洲（YRD）的碳循环，揭示了互花米草定植对 SOC 库及其稳定性的影响。SOC 含量范围为 1.29 g/kg-7.02 g/kg，其中互花米草覆盖的湿地随着定植时间的增加而增加，7 年后超过了本地物种覆盖的湿地。热裂解-气相色谱/质谱分析表明，SOC 的主要成分是芳香族物质，酚类和木质素化合物的含量呈显著增加趋势，而芳香族物质的含量随互花米草入侵时间的增加而减少。不同湿地中，磷脂脂肪酸（PLFA）反映出互花米草的微生物生物量最高。盐度对 SOC 库的影响最大为负，养分的影响最大为正。随着互花米草入侵时间的增加，分解抗性化合物（包括芳香族、木质素和酚类）在总 SOC 中的比例呈下降趋势，而 SOC 库则呈上升趋势。本研究表明，互花米草入侵可以促进 YRD 湿地 SOC 库的增加，但会降低其稳定性。
