枸杞岛海藻场三种大型海藻分解动态特征  

Decomposition dynamics of three macroalgal species inhabiting Gouqi Island seaweed bed

作　　者：刘章彬 王凯 陈奕帆 李训猛 章守宇 LIU Zhangbin;WANG Kai;CHEN Yifan;LI Xunmeng;ZHANG Shouyu(College of Marine Ecology and Environment,Shanghai Ocean University,Shanghai 201306,China)

机构地区：[1]上海海洋大学海洋生态与环境学院,上海201306

出　　处：《海洋湖沼通报》2023年第6期83-90,共8页Transactions of Oceanology and Limnology

基　　金：国家自然科学基金课题(41876191);现代农业产业技术体系专项资金(CARS-50)。

摘　　要：研究大型海藻腐烂分解过程以及养分动态对认识海藻场生态系统中物质循环过程有着重要意义。通过室外埋袋分解模拟实验,对枸杞岛海藻场优势种铜藻(Sargassum horneri)、舌状蜈蚣藻(Grateloupia livida)、石莼(Ulva lactuca L)的分解过程中营养成分变化以及不同温度梯度下三种大型海藻分解情况进行分析。结果表明,在48 d的分解过程中,舌状蜈蚣藻分解速率最快、铜藻其次、石莼最慢。分解过程中三种大型海藻的碳含量在分解前24 d变化波动较小,不同藻种氮含量的变化情况不同,磷含量在分解前期都有一个快速下降的过程,实验结束时,磷含量都有所降低。三种海藻的C/N和C/P变化总体趋势类似,C/N在分解过程中总体上处于下降的过程;C/P则是呈现出先上升后下降的趋势;N/P变化稍复杂,舌状蜈蚣藻呈上升-下降波动式变化,石莼和铜藻呈现出先上升后下降的过程。相关性分析结果表明,铜藻C/N越大,其分解率越低;石莼C/P越大,其分解率越低;不同温度梯度下的大型海藻分解率不同,表现为温度越高大型海藻分解越快。基于以上结果,建议在大型海藻养殖区或海洋保护区及时打捞衰老凋亡的藻体,尤其在温度较高的夏季对大型海藻腐烂藻体需妥善处理,以免大型海藻腐烂分解对海洋造成二次污染。It is of great significance to study the decomposition process and nutrient dynamics of macroalgae for understanding the material cycling process in the seaweed bed ecosystem.Through outdoor decomposition simulation experiment,the changes of nutrient components in the decomposition process of the dominant species Sargassum horneri,Grateloupia livida and Ulva lactuca L.and the decomposition of three macroalgae at different temperature gradients were analyzed.Measurement results demonstrated that the decomposition rate of G.livida was the fastest,which was followed by that of S.horneri and U.lactuca L.In the decomposition process,the carbon content of three macroalgae fluctuated slightly in the first 24 days of decomposition.The nitrogen content of different macroalgae changed differently,and the phosphorus content declined rapidly at the early stage of decomposition.At the end of the experiment,the phosphorus content decreased.The C/N and C/P of the three macroalgae were similar in general.The C/N ratio decreased in the decomposition process.C/P raised first and then falled down.The change of N/P was a little complicated.G.livida showed an up-down fluctuation while U.lactuca L.and S.horneri showed a process of rising first and then falling.Correlation analysis showed that the higher the C/N ratio of S.horneri,the lower the decomposition rate,the higher the C/P ratio of U.lactuca L.,the lower the decomposition rate.The decomposition rate of macroalgae remained different at different temperature gradients.The higher the temperature,the faster the decomposition of macroalgae.Our findings indicated that the aged and apoptotic algae should be salvaged in macroalgal culture areas and marine reserves in time,especially in summer when the temperature becomes high.It is necessary to deal with the decaying macroalgae properly to avoid the secondary pollution to the ocean.

关 键 词：大型海藻 分解过程 养分动态 温度 

分 类 号：S917.3[农业科学—水产科学]