论文部分内容阅读
有色可溶性有机物(colored dissolved organic matter,CDOM)光谱吸收特性是构建生物光学模型及水色遥感反演算法的重要基础。在2011年4月1日至5月中旬的东印度洋综合科学考察实验研究航次中,采集了6°N断面9个站位的CDOM样品并进行了测量;通过分析吸收系数aCDOM、光谱斜率值S、CDOM分子量相对大小的指示参数M值等参量,探讨了该断面处CDOM浓度与组成成分的分布及影响因素。分析结果发现,aCDOM(355)的变化范围为0.131—0.524m?1,平均值为0.272m?1;aCDOM(375)的变化范围为0.081—0.453m?1,平均值为0.242m-1,该范围小于近岸水体,高于东南太平洋海水,与南海北部18°N断面相近。叶绿素a浓度与CDOM吸收系数及光谱斜率没有表现出明显的相关性。CDOM光谱斜率的变化范围较大,其中S300—500nm的变化范围为0.008—0.019nm?1,平均值为0.012nm?1。S300—350nm与M值之间表现出正相关关系,吸收系数与光谱斜率及M值呈现出很好的负相关关系。结合该断面CTD资料发现,在30—90m水层高盐水团的影响下,M值在高盐区的平均值大于其右侧相同深度的结果,aCDOM(355)在高盐区的平均值小于其右侧相同深度的结果;在垂直方向上,受高盐水团影响区域M值没有表现出明显规律,而在其右侧则随着深度的增加M值逐渐减小,aCDOM(355)逐渐增加。
The chromatographic absorption characteristics of colored dissolved organic matter (CDOM) are the important basis for constructing bio-optical model and aquatic remote sensing inversion algorithm. From April 1, 2011 to mid-May, the CDOM samples of 9 stations in the 6 ° N section of the East Indian Ocean Integrated Scientific Expedition were collected and measured. By analyzing the absorption coefficient aCDOM, the spectral slope S , CDOM molecular weight relative size of the indication parameter M value and other parameters, to explore the CDOM concentration and composition of the distribution and influencing factors. The results showed that the range of aCDOM (355) was 0.131-0.524 m -1, the average was 0.272 m -1, the range of aCDOM 375 was 0.081-0.453 m -1, the average was 0.242 m -1, This range is smaller than that of nearshore bodies and higher than that of the southeast Pacific Ocean, similar to the 18 ° N section of the northern South China Sea. Chlorophyll a concentration showed no significant correlation with CDOM absorption coefficient and spectral slope. The range of variation of CDOM spectral slope is larger, in which the range of S300-500nm is 0.008-0.019nm? 1, the average is 0.012nm? 1. S300-350nm and M values showed a positive correlation between the absorption coefficient and the spectral slope and M values showed a good negative correlation. According to the CTD data of this section, it is found that the average value of M value in the high salt area is greater than the right depth in the 30-90m water layer. The average value of aCDOM (355) in the high salt area is less than The same depth on the right side. In the vertical direction, the value of M in the area affected by the high-salinity water does not show a clear rule, while on the right side, the value of M decreases gradually as the depth increases, and the value of aCDOM (355) gradually increases .