经泥沙遥感参数校正的辐射沙洲水深遥感模型研究

【作者】 陶菲；

【导师】 张鹰；

【作者基本信息】 南京师范大学 ， 海洋地理学， 2007， 硕士

【摘要】 随着遥感技术的发展，水深遥感方法逐渐成为被人们认识、接受的一种水深量测的高科技方法。本文基于“中国近海海洋综合调查与评价”，以辐射沙洲烂沙洋区域为研究对象，并结合实测泥沙浓度和光谱反射率数据，对水深遥感方法及悬浮泥沙对遥感测深影响等方面进行了研究。研究结论如下：（1）对比分析实测水深值和遥感影像像元反射率之间的相关性，选取单波段或波段组合作为反演因子，建立了多种水深反演模型，经独立样本检验，发现非线性多因子模型的反演精度明显高于线性模型和单波段非线性模型。（2）悬浮泥沙含量较低时，遥感反射率曲线只有一个峰值，出现在570～580nm；悬浮泥沙含量较高时，反射率曲线出现两个峰值，主峰值位于580～590nm之间，次峰出现在810nm左右。随着悬浮泥沙含量的进一步增加，红光至近红外波段的反射率不断增大，主峰与次峰之间的差距也逐渐减小。（3）计算了各波段标准反射率和悬沙浓度、泥沙浓度对数之间的相关系数，并参考了国内外比较公认的Ⅱ类水体悬浮泥沙反演模式，最终选取490、550和670nm作为敏感波段，构建了泥沙遥感参数X_s=（R₂+R₃）／（R₁／R₂）。（4）将泥沙参数、泥沙参数对数和各波段及波段组合进行比值运算，发现泥沙参数对数与波段比值后结果与水深相关性有所提高，说明一定程度上削弱了悬浮泥沙对各波段光谱反射率的影响。（5）利用已削弱泥沙信息的波段和波段组合重新构建了水深反演因子，建立了引入泥沙遥感参数的水深反演模型，经独立样本检验，该模型的精度可达81％，优于其它建立的所有模型。更多还原

【Abstract】 With the development of remote sensing, the means of remote sensing is the high way to detect the water depth, which is known and accepted by people gradually. Based on the important item of Chinese offshore investigation and assessment, the paper took the major tidal channel in radial submarine sand ridges system of Jiangsu Province as a study object, combining with the in-situ measured suspended sediment concentration and spectral data, the water depth mapping by remote sensing and spectral characters of suspended sediment were studied. The conclusions as follows:（1）Several models were constructed to retrieve the water depth information of the study area by analyzing and comparing the relationship between reflectance derived from Landsat 5 TM satellite data and water depth information. Results show that the non-linear multiple regress model can express better than the line models and non-linear single factor models.（2）When the concentration of suspended sand is low, the water spectral reflectance only has one peak, the peak is in the bands of 570-580nm; when the concentration is higher, the reflectance appears double peaks, the first peak is in the wave bands of 580-590nm, the second lie about in 810nm. The percentage reflectance increases with suspended sediment concentration at red band and near Infrared band, the difference between two peaks is shorten too.（3） Based on calculating the relation coefficient between standard reflectance between suspended sediment concentration（SSC） and Ln（SSC） and consulting the known conclusions home and abroad, we finally took 490550 and 670 nm as sensitive waves to construct suspended sediment remote sensing parameter: X_s = （R₂+R₃）/（R₁/R₂）.（4）It was found that the relationship between reflectance and water depth has been improved greatly by band ratio of Ln（SSC） and single band and band combination. The result showed that the effects of suspended sediment on the water depth were decreased, so it allows the water depth information to be retrieved at a relatively high accuracy level.（5）The model for water depth remote sensing was re-constructed by single band and band combination which had been reduced suspended sediment information. The average estimated accuracy was more than 81% in the study region.更多还原