Bathymetric estimation through principal components analysis using IKONOS-2 data

Abstract

The use of satellite remote sensing images could be a valid alternative to the classical methods of bathymetric measurements for depths less than 30 meters. In this work, several pixels corresponding to different depths are considered to numerically evaluate the relation between the water spectral response and the real depth, in the Douro River Estuary (Porto, Portugal). The main concept relies on principal components analysis, which allows for combining the information of the n available spectral bands from the image into an equal number n of principal components. The dataset is composed by an IKONOS-2 image and bathymetric values. An initial analysis was performed in order to determine the viability of the data for bathymetric study of the Douro River estuary. It was proved that it was not possible to find any direct relationship between the DNs of the IKONOS-2 image and depth values. Therefore, a simple linear regression of the bathymetric values on the IKONOS-2 image principal components was considered. A significant correlation was found between the first principal component and the real depths. In the future, the use of simultaneous data and the use of other statistical models such as decision trees may also provide important contributes to improve this methodology.

Environmental applications of remote sensing

“…Remote Sensing-Based Biomass Estimation http://dx.doi.org/10.5772/61813 with distinct surface layers toward a laser scanner that can be mounted on an aerial or terrestrial platform [123,125,126].…”

“…The first one is associated with first returns and the second one is related to the last returns. Other forest structural measurements are the fractional crown cover, crown area, crown diameter, basal area [38,125], and canopy volume [126], which are of key interest to the managers and represent information that is expensive and time consuming to collect in the field. When small-footprint LiDAR data are acquired at very high enough densities, individual tree crowns can readily be observed in the point clouds, processing algorithm for automated measuring and modeling of vegetation at individual tree crown segmentation (e.g., watershed segmentation) [95,128,129].…”

“…Biomass modeling through this approach has been usually used in simple and multiple regression models [38,125,126,130]. Other works have explored the use of learning machines [131,132].…”

“…Teodoro et al[125] propose a model for the estimation of depth based on Principal Component Analysis (PCA) of an IKONOS-2 image, for the Douro River estuary (Porto, Portugal). Subsequently, Teodoro et al[117] proposed alternative univariate and bivariate models for the same IKONOS-2 image based on PCA and Independent Component Analysis (ICA).…”

Optical Satellite Remote Sensing of the Coastal Zone Environment — An Overview

“…Teodoro et al[125] propose a model for the estimation of depth based on Principal Component Analysis (PCA) of an IKONOS-2 image, for the Douro River estuary (Porto, Portugal). Subsequently, Teodoro et al[117] proposed alternative univariate and bivariate models for the same IKONOS-2 image based on PCA and Independent Component Analysis (ICA).…”