莱州湾荧光溶解有机物的时空分布

利用三维荧光光谱-平行因子分析法(EEMs-PARAFAC)技术结合多元统计方法研究了莱州湾海域春季(2020年5月)和秋季(2020年10月)荧光溶解有机物(FDOM)的来源及时空分布特征。结果显示莱州湾海域FDOM由2类共4个荧光组分组成:C1、C4为类蛋白质组分,分别为色氨酸和酪氨酸; C2、C3为类腐殖质组分。并对各组分的来源及分布特征分析:春季FDOM分布主要受到陆源输入的影响,其中表层C1、C2、C3也受微生物活动影响。秋季表层C1、C2、C3分布受到陆源输入和浮游植物生产共同影响,秋季表层C4主要受生物现场生产影响,秋季底层C1、C2、C3主要受陆源输入影响,C4受陆源输入和浮游植物生产共同影响。各荧光组分在表层的季节性差异主要是由于春季部分FDOM经陆源输入后受偏南风作用,在莱州湾西部及南部海域扩散。FDOM在底层的季节性差异主要由于受到沉积物再悬浮的影响。HIX高值分布表明莱州湾西部和南部FDOM受陆源输入影响显著,BIX高值分布表明莱州湾远海FDOM受生物活动影响程度较高。总体上,陆源输入影响莱州湾FDOM分布的主要因素。

Spatial and temporal distribution of fluorescent dissolved organic matter in Laizhou Bay

Excitation and emission matrix spectroscopy and parallel factor analysis (EEMs-PARAFAC) was used to study the source and spatial distribution characteristics of fluorescent dissolved organic matter (FDOM) in the Laizhou Bay in spring (May 2020) and autumn (October 2020). The FDOM in the Laizhou Bay is composed of two types of four fluorescent components: C1 and C4 are protein-like components, tryptophan and tyrosine, respectively; C2 and C3 are terrestrial humus components. The source and distribution of each component are analyzed: The distribution of FDOM in spring is mainly affected by terrestrial input, and the surface layer C1, C2, C3 are also affected by microbial organic matter processes. The distribution of C1, C2, and C3 in the surface layer in autumn is affected by both terrestrial input and phytoplankton production, and C4 is mainly affected by onsite biological production. C1, C2, and C3 of the bottom layer in autumn are mainly affected by terrestrial input, and C4 is affected by both terrestrial input and phytoplankton production. The seasonal difference of the various fluorescent components in the surface layer is mainly due to the fact that part of the FDOM in spring is affected by the southerly wind after being imported from land sources, and it spreads in the western and southern waters of the Laizhou Bay. The seasonal difference of FDOM in the bottom layer is mainly due to the influence of sediment resuspension. The distribution of high values of HIX indicates that FDOM in the western and southern Laizhou Bay is significantly affected by terrestrial input, and the distribution of high values of BIX indicates that FDOM in the open sea of Laizhou Bay is highly affected by biological activities. In general, land-based input is the main factor affecting the distribution of FDOM in Laizhou Bay. This paper uses excitation and emission matrix spectroscopy and parallel factor analysis (EEMs-PARAFAC) technology combined with multivariate statistical methods to analyze the sources and distribution differences of FDOM in the spring and autumn of Laizhou Bay, and provide supplements for FDOM research in other sea areas.