In February and July 2014, multidisciplinary geochemical studies of the sediments were carried out at two stations. One of them was located in Voevoda Bight, which has a bottom depth of 4 m, covered by eelgrass (Zostera marina L.); the other one served as a background station, because it is devoid of seagrass and is located in the northern part of Amur Bay (near Rechnoj Island). This station has a bottom depth of 6 m. The chemical composition of sediment pore water was studied along the depth of the core (80 cm) for the following: concentrations of dissolved organic carbon, carbohydrates, humic substance, nutrients (inorganic phosphorus, silicon, ammonium), and the parameters of the carbonate system (pH, total alkalinity—TA, dissolved inorganic carbon—DIC, CO₂ partial pressure—pCO₂). Contents of organic carbon (OC), fulvic acids, humic acids, and water were measured in the sediment solid phase. It was established that that the OC concentration was more than 5 and 2% in Voevoda Bight and at the background station, respectively. The sum of the fulvic and humic acids was about 40% of the OC content. It was found that the OC content decreased by 50% within 40 cm of the top layer of the sediments in Voevoda Bight. Within the same layer, a sharply increased nutrient concentration, TA, and DIC and decreased pH and sulfate ion concentrations were observed, which were the opposite of the background station. Seasonal variability of the observed parameters was weak, except for the significant decrease in pH and increase in pCO₂ observed in summer due to temperature effect on the constants of the carbonate system. The chemical composition of pore water suggests that sulfate reduction was an important process. However, it cannot explain the sharp decrease in OC; therefore, it was suggested that OC is transformed into infauna biomass by the food chain.

中文翻译：

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鳗草植被沉积物中有机质的成岩作用

2014年2月和2014年7月，在两个站点进行了沉积物的多学科地球化学研究。其中之一位于沃沃达湾，其底部深度为4 m，被鳗鱼草覆盖（Zostera marina L.）。另一个作为背景站，因为它没有海草，并且位于阿穆尔湾北部（雷希诺伊岛附近）。该站的底部深度为6 m。沿着岩心深度（80厘米）对沉积物孔隙水的化学成分进行了以下研究：溶解的有机碳，碳水化合物，腐殖质，营养物（无机磷，硅，铵）的浓度以及碳酸盐的参数系统（pH，总碱度—TA，溶解的无机碳—DIC，CO ₂分压—pCO₂）。在沉积物固相中测量了有机碳（OC），富里酸，腐殖酸和水的含量。已经确定，Voevoda Bight和背景站的OC浓度分别超过5％和2％。黄腐酸和腐殖酸的总和约为OC含量的40％。已发现在Voevoda Bight，沉积物顶层40 cm内的OC含量降低了50％。在同一层中，观察到养分浓度，TA和DIC急剧增加，pH和硫酸盐离子浓度下降，这与背景站相反。除了pH显着降低和pCO ₂升高外，所观察到的参数的季节性变化很小。由于温度对碳酸盐体系常数的影响，夏季观测到了这种现象。孔隙水的化学成分表明硫酸盐还原是一个重要的过程。但是，它不能解释OC的急剧下降。因此，建议通过食物链将OC转化为动物的生物量。