Calace N, Cardellicchio N, Petronio B M, Pietrantonio M, Pietroletti M
Department of Chemistry, University of La Sapienza, p.le A Moro 5, 00185 Rome, Italy.
Mar Environ Res. 2006 Feb;61(1):40-58. doi: 10.1016/j.marenvres.2005.05.002. Epub 2005 Jul 14.
Humic compounds were determined in sediments collected in an area of the Adriatic sea receiving fresh waters from the river Po. Sediment cores (10 cm) were sectioned into four layers which were analysed separately for redox potential (Eh), total phosphorus (TP), total organic carbon (TOC), humic (HA) and fulvic acid (FA) content. The structure of HA and FA was also investigated. The results showed that the TOC and TP content decreased from the coast to the open-sea stations. Humic and fulvic acid concentrations were also inversely correlated to the distance from the coast. Moreover, the humic and fulvic acids were closely correlated to the total organic content and to the total phosphorus content. The correlations found between humic substances (HS) and TOC and TP, respectively, could be explained both by an in situ formation due to the high content of nutrients and organic matter, and by a common source of HS, TOC and TP, namely the River Po discharge. The predominant presence of aliphatic carbon in the humic structures, the low degree of substitution and the high nitrogen content suggest that primarily humified compounds were formed in situ. Nevertheless, the River Po can act both as supplier of organic matter of which decomposition products lead to the formation of humic compound and as carrier of humified compounds.
在亚得里亚海一个接收波河淡水的区域采集的沉积物中测定了腐殖化合物。将沉积物岩心（10厘米）切成四层，分别分析其氧化还原电位（Eh）、总磷（TP）、总有机碳（TOC）、腐殖酸（HA）和富里酸（FA）含量。还研究了HA和FA的结构。结果表明，从海岸到公海站点，TOC和TP含量降低。腐殖酸和富里酸浓度也与离海岸的距离呈负相关。此外，腐殖酸和富里酸与总有机含量和总磷含量密切相关。腐殖物质（HS）与TOC和TP之间的相关性，既可以用由于营养物质和有机物质含量高而就地形成来解释，也可以用HS、TOC和TP的共同来源即波河排放来解释。腐殖结构中脂肪族碳的占主导地位、低取代度和高氮含量表明，主要是就地形成了腐殖化化合物。然而，波河既可以作为分解产物导致腐殖化合物形成的有机物质的供应者，也可以作为腐殖化化合物的载体。
