长江口邻近海域冬季水体漫衰减特性及遥感反演初探

发布时间：2019-03-28 14:31

【摘要】：本文采用2012年和2013年冬季长江口邻近海域的实测数据,分析了该区域漫衰减系数光谱特征,490nm波段向下漫衰减系数(Kd(490))的空间分布及影响因子,分析了叶绿素、CDOM.总悬浮物与Kd(490)的关系。建立了该研究区域Kd(490)与有效光合辐射衰减系数(Kd(PAR))的关系式和总悬浮物浓度与Kd(490)的关系式。结果表明：长江口邻近区域Kd490值随着离岸距离的减小逐渐增大,最大值达到了1.8m-1,杭州湾邻近区域情况类似,舟山岛附近出现了Kd(490)的最大值2.8m-1。总悬浮物对Kd(490)的影响较大,悬浮物浓度与Kd(490)相关度大于0.86。黄色物质和叶绿素a对其影响较小,与Kd(490)相关度均小于0.25。光合有效辐射衰减系数(Kd(PAR))与Kd(490)的关系：Kd(PAR)=0.495eXp(0.8602Kd(490))-0.2217,对比反演与实测结果显示：均方根误差为0.102m-1,平均相对误差为14.62%,决定系数为0.927；总悬浮物浓度(TSM)与Kd(490)的关系：Kd(490)=1.988+3.61*TSM+3.198*TSM2,对比反演与实测结果显示：均方根误差为0.103m-1,平均相对误差为25.6%,决定系数为0.895。在文献研究的基础和对主要影响因子分析的基础上建立了三波段遥感反射率与Kd(490)的反演模式：lg[Kd(490)]=a[Rrs(590)/Rrs(510)]+b[Rrs(670)/Rrs(510)],对比反演与实测结果显示：均方根误差为0.098m-1,平均相对误差为12.43%,决定系数为0.916；并对400-700nm的漫衰减系数进行了参数化,得到参数化公式Kd(λ)=k(λ)*Kd(490)+b(λ),其中k=1.158*10-5λ2-0.01561*λ+5.8573b=1.408*10-5*λ2-0.01363*λ+3.3054,利用剩余八组数据进行验证,得到结果显示：八组数据的平均相对误差范围为0.024～0.0985,均方根误差范围为0.032-0.074,相关性系数范围为0.947-0.988,参数化结果良好。本文分析了冬季长江口邻近海域光合有效辐射(PAR)的分布,并进行归一化处理,得到水下归一化PAR的垂直分布及其该研究区域的不同水深处的分布趋势,计算得出真光层深度,并使用VGPM模型计算得出冬季长江口初级生产力。分析及计算结果表明,归一化PAR强度随水深的增大不断减小,其与真光层深度存在良好的二次多项式拟合关系；真光层具有离岸越远,深度越大的趋势；初级生产力在冬季受到真光层深度的影响较大,并在东经123。,北纬31.75。处形成最高值区域,并最高值区为中心,向外减小的分布趋势。
[Abstract]:Based on the measured data of the Yangtze estuary in winter of 2012 and 2013, the spatial distribution and influence factors of the diffuse attenuation coefficient spectral characteristics, 490nm band downward diffuse attenuation coefficient (Kd (490) are analyzed. Chlorophyll, CDOM. are analyzed in this paper. The relationship between total suspended matter and Kd (490). The relationship between Kd (490) and effective photosynthetic radiation attenuation coefficient (Kd (PAR) and the relationship between total suspended matter concentration and Kd (490) were established. The results show that the KD 490 value in the adjacent area of the Yangtze River Estuary gradually increases with the decrease of the offshore distance, and the maximum value reaches 1.8 mm2. The situation is similar in the adjacent area of Hangzhou Bay. The maximum value of Kd (490) is 2.8m / 1 near Zhoushan Island. The influence of total suspended matter on Kd was greater than 0.86. The correlativity between suspended matter concentration and Kd (490) was more than 0.86. Yellow substance and chlorophyll a had little effect on them, and their correlation with Kd was less than 0.25. The relationship between the attenuation coefficient of photosynthetic effective radiation (Kd (PAR) and Kd (490) is: Kd (PAR) = 0.495eXp (0.8602Kd (490)-0.2217.Contrastive inversion and measured results show that the root mean square error (RMS) is 0.102 mm2, The average relative error was 14.62% and the determination coefficient was 0.927; The relationship between total suspended matter concentration (TSM) and Kd (4909) is 1.988 3.61*TSM 3.198TSM2. The results of contrast inversion and measurement show that the root mean square error is 0.103mm2, the average relative error is 25.6%, and the mean root mean square error (RMS) is 0.103mm2 and the mean relative error is 25.6%. The determination coefficient is 0.895. On the basis of literature research and analysis of main influence factors, the inversion model of three-band remote sensing reflectivity and Kd is established: LG [KD] = a [RRS (590) / Rrs (510)] b [Rrs (670) / Rrs (510)], The results of contrastive inversion and measurement show that the root mean square error is 0.098 m / 1, the average relative error is 12.43%, and the determination coefficient is 0.916; The parameterization formula Kd (位) = k (位) * Kd (490) b (位) is obtained by parameterizing the diffuse attenuation coefficient of 400-700nm. Among them, 1.158 脳 10-5 位 2-0.01561 * 位 5.8573b / 1.408 / 10 / 5 * 位 2-0.01363 * 位 3.3054, and the remaining eight sets of data were used for verification. The results show that the average relative error range of eight groups of data is 0.024 ~ 0.0985, the mean square root error is 0.032 ~ 0.074, the correlation coefficient is 0.947 ~ 0.988, and the parameterization result is good. In this paper, the distribution of (PAR) in the waters adjacent to the Yangtze River Estuary in winter is analyzed and normalized, and the vertical distribution of the normalized PAR under water and the distribution trend of the different depths of the water in the study area are obtained. The depth of the true light layer is calculated, and the primary productivity of the Changjiang Estuary in winter is calculated by using the VGPM model. The analysis and calculation results show that the normalized PAR intensity decreases with the increase of water depth, and there is a good quadratic polynomial fitting relationship between the normalized intensity and the depth of the euphotic layer, and the farther the offshore the greater the depth of the euoptical layer is. The primary productivity was greatly affected by the depth of euphotic layer in winter, and it was at 123. 3 E and 31. 75. 5 N. At the same time, the highest value area is formed, and the highest value region is the center, and the distribution trend decreases outward.
【学位授予单位】：华东师范大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：P733.3;P714.3

【相似文献】