The source and distribution of dissolved and particulate organic matter in the Bay of St. Louis, northern Gulf of Mexico
The source and distribution of dissolved and particulate organic matter in the Bay of St. Louis, northern Gulf of Mexico
复制标题
墨西哥湾北部圣路易斯湾溶解有机物和颗粒有机物的来源和分布
DOI：
10.1016/j.ecss.2011.10.017
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发表时间：
2012-01-01
影响因子：
2.8
通讯作者：
Redalje, Donald G.
中科院分区：
文献类型：
--
作者：
Cai, Yihua;Guo, Laodong;Redalje, Donald G.
2007 年 3 月 9 月期间，从墨西哥湾北部的圣路易斯湾 (BSL) 采集了溶解 (DOM) 和颗粒有机物 (POM) 样品，进行化学和同位素表征，以检查河口环境中有机物种类的分布和来源。与水文参数和营养盐的变化类似，有机碳、氮和磷的浓度以及稳定同位素组成在采样期间表现出较大的空间和季节变化。溶解有机碳（DOC）和溶解有机氮（DON）的浓度随着盐度的增加而降低，而δ C-13-DOC随着盐度的增加而增加，从-30.23 ppm增加到-19.04 ppm，这表明在河口混合过程中DOC来源从陆地主导输入转变为海洋主导输入。与 DOC 和 DON 相比，溶解有机磷 (DOP) 的浓度随着盐度的增加而增加，表明盐度较高的站有更多的 DOP 来源。颗粒有机碳（POC）和氮（PN）浓度随着盐度的增加而降低，与悬浮颗粒物浓度呈负相关。 POC/PN 比值 (8.6-19.6) 和 Delta C-13-POC (-28.51 ppm 至 -23.79 ppm) 总体上随着盐度的增加而增加，表明上湾中陆地来源的有机质占主导地位，而下湾中成岩改变的海洋 POM 成分增加。根据 POC/Chl a 比率估计，新鲜微藻可能占 BSL 中 POM 的三分之一左右。总体而言，陆地输入、原位初级生产和主要来自沉积物再悬浮的成岩改变的海洋 POM 是 BSL 中 POM 的主要来源。 (C) 2011 Elsevier Ltd. 保留所有权利。
Dissolved (DOM) and particulate organic matter (POM) samples were collected from the Bay of St. Louis (BSL) in the northern Gulf of Mexico during March September, 2007 for chemical and isotopic characterization to examine the distribution and sources of organic matter species in the estuarine environment. Similar to the variations in hydrographic parameters and nutrients, concentrations of organic C, N, and P and stable isotopic composition show large spatial and seasonal variations during the sampling period. Concentrations of dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) decreased with increasing salinity while delta C-13-DOC increased with salinity from -30.23 parts per thousand to -19.04 parts per thousand, suggesting a shift of DOC sources from terrestrial- to marine-dominated inputs during estuarine mixing. In contrast to both DOC and DON, the concentration of dissolved organic phosphorus (DOP) increased with increasing salinity, indicating additional DOP sources at higher salinity stations. Concentrations of particulate organic carbon (POC) and nitrogen (PN) decreased with increasing salinity, showing a negative correlation with the concentration of suspended particulate mater. Both POC/PN ratio (8.6-19.6) and delta C-13-POC (-28.51 parts per thousand to -23.79 parts per thousand) increased in general with increasing salinity, indicating the predominance of terrestrially derived organic matter in the upper bay and increasing diagenetically altered marine POM component in the lower bay. Fresh microalgae might account for about one third of POM in the BSL as estimated from POC/Chl a ratio. Overall, the terrestrial inputs, in situ primary production and diagenetically altered marine POM mostly from sediment resuspension are the major sources of POM in the BSL. (C) 2011 Elsevier Ltd. All rights reserved.