Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China.
Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China.
Sci Total Environ. 2022 Aug 20;835:155351. doi: 10.1016/j.scitotenv.2022.155351. Epub 2022 Apr 20.
GRSP is widely distributed in coastal wetlands, and there is a tendency for it to degrade with increasing burial depth. However, the dynamic changes in the chemical composition and stability of GRSP during the burial process are still unclear. The purpose of this study is to clarify the chemical composition and accumulation characteristics of GRSP during the burial process in the Zhangjiang estuary. In a field study, soil cores to the depth of 100 cm were collected in the estuary from mangrove forests dominated by Kandelia obovata and Avicennia marina, and from mudflat. The results showed that the concentration of GRSP in mangrove forest soil was significantly higher than that in the mudflat (p < 0.05), and the C/N ratio of GRSP increased with depth at all sites. Analysis of Fourier transform infrared (FTIR) data showed that the degradation rates of the GRSP's compositions varied with increasing burial depth, with microbial action and pH possibly being the main factors affecting degradation. Values of recalcitrance index (RI) showed that the stability of GRSP increased with increasing depth, and the contribution of GRSP to soil organic carbon (SOC) also increased. This suggests that the burial process plays a role in screening and storing the stable components of GRSP. Overall, our findings suggest that the concentration and chemical composition of GRSP vary dynamically according to habitat and burial processes. In addition, the improved stability of GRSP could contribute to carbon sequestration in coastal wetlands.
GRSP 在沿海湿地中广泛分布，且随着埋藏深度的增加有降解的趋势。然而，GRSP 在埋藏过程中化学组成和稳定性的动态变化仍不清楚。本研究旨在阐明在长江口埋藏过程中 GRSP 的化学组成和积累特征。在一项野外研究中，从以白骨壤和桐花树为主的红树林和泥滩采集了至 100cm 深的土壤芯。结果表明，红树林土壤中 GRSP 的浓度明显高于泥滩（p < 0.05），并且在所有地点 GRSP 的 C/N 比随深度增加而增加。傅里叶变换红外（FTIR）数据分析表明，GRSP 组成的降解速率随埋藏深度的增加而变化，微生物作用和 pH 值可能是影响降解的主要因素。抗降解指数（RI）值表明 GRSP 的稳定性随深度增加而增加，GRSP 对土壤有机碳（SOC）的贡献也增加。这表明埋藏过程在筛选和储存 GRSP 的稳定成分方面发挥了作用。总的来说，我们的研究结果表明，GRSP 的浓度和化学组成根据生境和埋藏过程而动态变化。此外，GRSP 稳定性的提高可能有助于沿海湿地的碳封存。
