Macroalgae bloom decay decreases the sediment organic carbon sequestration potential in tropical seagrass meadows of the South China Sea
Macroalgae bloom decay decreases the sediment organic carbon sequestration potential in tropical seagrass meadows of the South China Sea
复制标题
大型藻华衰退降低了南海热带海草甸沉积物有机碳封存潜力
DOI：
10.1016/j.marpolbul.2018.12.009
复制
发表时间：
2019
影响因子：
5.8
通讯作者：
Xiaoping Huang
中科院分区：
文献类型：
--
作者：
Songlin Liu;Zhijian Jiang;Yunchao Wu;Juan Feng;Qiming Chen;Chunyu Zhao;Lijun Cui;Xiaoping Huang
海草草甸正在经历世界范围内的下降，主要是因为养分富集，这总是导致大型藻类水华，从而周期性的崩溃和分解。然而，大型藻类腐烂对沉积物有机碳（SOC）固存能力的影响尚不清楚。以南海富营养化海草草甸大型藻类生物量为研究对象，采用室内箱试验研究了常见大型藻类水华（Cladophora spp.）分解大型藻类分解对脱氢酶和β-葡萄糖苷酶活性没有影响，但显著提高了盐可提取碳（SEC）含量、SEC/SOC、转化酶和多酚氧化酶活性以及CO2释放量。总体而言，海藻分解促进了土壤有机碳的转化，不利于南海海草草甸土壤有机碳的固定。
Seagrass meadows are experiencing worldwide declines mainly because of nutrient enrichment, which always result in macroalgae bloom and consequently periodic collapse and decomposition. However, effects of macroalgae decay on the sediment organic carbon (SOC) sequestration capacity remain unknown. Depending on the macroalgae biomass in eutrophic seagrass meadows of South China Sea, we carried out a laboratory chamber experiment to investigate the sediment labile organic carbon (OC) compositions and the influencing SOC transformation enzyme activity variations of seagrass meadows in response to common macroalgae bloom species (Cladophora spp.) decomposition. Although the dehydrogenase and β-glucosidase activities were not affected by macroalgae decomposition, the macroalgae decomposition significantly elevated the salt-extractable carbon (SEC) content, SEC/SOC, levels of invertase and polyphenol oxidase activities, and the CO2 release. Overall, this study indicates that macroalgae decomposition stimulates the SOC transformation, and therefore, it is not benefit for SOC sequestration within seagrass meadows of the South China Sea.