舟山枸杞岛大型海藻凋落物分解特征及其影响因素

Litter decomposition characteristics and influencing factors of macroalgae in gouqi island of Zhoushan

为探明大型海藻凋落物的分解特征以及调控因素,以枸杞岛海藻场两个优势藻种铜藻(Sargassum horneri)和鼠尾藻(Sargassum thunbergii)作为研究对象,利用分解网袋法,研究了铜藻和鼠尾藻的主干和侧枝凋落物的分解过程。结果表明:(1)海藻的侧枝分解速率大于主干,并且鼠尾藻各部位的分解速率大于铜藻;(2)海藻的N含量在分解过程中有不同程度的固持和释放,C含量在整个分解过程中呈下降趋势,P含量在分解前期有个快速衰减过程,随着分解的进行,衰减逐渐减慢;(3)海藻体内的化学组分含量和环境因素对海藻的分解速率有不同程度的影响,其中,水温对海藻分解率的影响最为显著,呈极显著正相关(P<0.01)。

In order to explore the characteristics and regulatory factors of decomposition of macroalgal litter,the decomposition process of the main and lateral branches of Sargassum horneri and Sargassum thunbergii,two dominant algae species in gouqi Island algal farm,was studied by decomposing mesh bag method.The results showed that:(1)the decomposition rate of lateral branches was faster than that of main branches,and the decomposition rate of different parts of Sargassum was faster than that of copper algae;(2)The N content of seaweed had different degrees of fixation and release in the decomposition process,the C content showed a downward trend in the whole decomposition process,and the P content had a rapid decay process in the early stage of decomposition,and gradually decreased with the decomposition process;(3)The results of correlation analysis showed that the contents of chemical components in seaweed and environmental factors had different degrees of influence on the decomposition rate of seaweed,and the water temperature had the most significant effect on the decomposition rate of seaweed,showing a very significant positive correlation(P<0.01).