Jiangsu Key Laboratory of Coast Ocean Resources Development and Environment Security, Nanjing 210098, China.
College of Harbour, Coastal and Offshore Engineering, Hohai University, Nanjing 210098, China.
Ying Yong Sheng Tai Xue Bao. 2023 Nov;34(11):2978-2984. doi: 10.13287/j.1001-9332.202311.030.
We measured winter and summer soil organic carbon (SOC) contents in two typical coastal wetlands, the salt marsh and the non-vegetation mudflat, on the south side of the Chuandong River Estuary in Yancheng, Jiangsu Province. We investigated the spatiotemporal variations of soil organic carbon contents and its driving factors. The results showed that SOC content ranged from 0.75 to 2.38 g·kg in the mudflat area and from 2.07 to 18.59 g·kg in the salt marsh area, showing a decreasing trend towards the sea. The SOC content in the salt marsh area was approximately 2.5 to 3.5 times of that in the mudflat area. Within a depth range of 1 m, there was no vertical variation in SOC content in the mudflat area, but an increasing and then decreasing pattern in the marsh area with the peak occurring in the depth range of 20 to 30 cm. Soil organic carbon content exhibited significant seasonal difference, with higher value in summer than in winter. The summer SOC content was 5% to 10% higher than that in winter in the marsh area, while it was 43% higher in summer than in winter in the mudflat area. In the marsh area, soil organic carbon content was positively correlated with soil moisture and salinity, but negatively correlated with sediment particle size. In contrast, there was no significant correlation between soil organic carbon content and soil physicochemi-cal factors in the mudflat area. Those results indicated that the correlation between various soil physicochemical factors and SOC is established on the basis of vegetation cover in coastal wetlands. Our findings could provide valuable insights for the conservation of blue carbon ecosystems in coastal wetlands in China.
我们在江苏省盐城市川东港南侧的两个典型滨海湿地（盐沼和无植被泥滩）测量了冬夏两季的土壤有机碳（SOC）含量，研究了土壤有机碳含量的时空变化及其驱动因素。结果表明，泥滩区 SOC 含量范围为 0.75 至 2.38 g·kg，盐沼区 SOC 含量范围为 2.07 至 18.59 g·kg，均表现出向海递减的趋势。盐沼区 SOC 含量约为泥滩区的 2.5 至 3.5 倍。在 1 m 深度范围内，泥滩区 SOC 含量无垂直变化，但盐沼区呈增加后减少的趋势，峰值出现在 20 至 30 cm 深度范围内。SOC 含量具有显著的季节性差异，夏季高于冬季。盐沼区夏季 SOC 含量比冬季高 5%至 10%，而泥滩区夏季 SOC 含量比冬季高 43%。在盐沼区，土壤有机碳含量与土壤水分和盐分呈正相关，与沉积物粒径呈负相关。相比之下，泥滩区土壤有机碳含量与土壤理化因子之间无显著相关性。这些结果表明，各种土壤理化因子与 SOC 的相关性是在滨海湿地植被覆盖的基础上建立的。我们的研究结果可为保护中国滨海湿地蓝碳生态系统提供有价值的见解。
