Assessing Reclamation Levels of Coastal Saline Lands with Integrated Stepwise Discriminant Analysis and Laboratory Hyperspectral Data

doi:10.1016/S1002-0160(06)60038-6

Pedosphere

Volume 16, Issue 2, April 2006, Pages 154-160

https://doi.org/10.1016/S1002-0160(06)60038-6 Get rights and content

ABSTRACT

At different times over the past 30 years in Zhejiang Province, China, the coastal tidelands have been successively enclosed and reclaimed for agricultural land use. The purpose of this work was to evaluate whether laboratory hyperspectral data might be used to estimate the physicochemical characteristics of these reclaimed saline soils. A coastal region of Shangyu City (Zhejiang Province), which was grouped into four subzones according to reclamation history, was used as the study area, and soil samples were collected in each subzone. Physicochemical analyses showed that the soils were characterized by high electrical conductivity and sand content with low organic matter; the longer the saline lands had been reclaimed, the lower were the electrical conductivity and sand content and the higher the organic matter content. These changing trends of soil chemical and physical properties were found in laboratory reflectance spectra of soil samples and their first-order derivative curves. Stepwise discriminant analysis (SDA) identified six salient spectral bands at 488, 530, 670, 880, 1400, and 1900 nm. Using derived discriminant functions for saline lands with different historical years of reclamation, classification revealed an overall accuracy from a self-test of 86.6% and from cross-validation of 89.3%. Therefore, as opposed to time-consuming field investigations, this study suggested that remotely sensed hyperspectral data could serve as a promising measure to assess the reclamation levels of coastal saline lands.

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¹: Project supported by the German Federal Ministry for Research and Education, Germany (No. AZ39742), and the National Natural Science Foundation of China (No. 40571066).

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Assessing Reclamation Levels of Coastal Saline Lands with Integrated Stepwise Discriminant Analysis and Laboratory Hyperspectral Data1

ABSTRACT

Biosystems Engineering

Remote Sensing of Environment

Remote Sensing of Environment

Remote Sensing of Environment

Remote Sensing of Environment

The spectral reflectance properties of soil structural crusts in the 1.2- to 2.5-μm spectral region

Soil Science Society of America Journal

Quantitative approach in the spectral reflectance-lithostratigraphy of the Wind River and southern Bighorn basins, Wyoming

International Journal of Remote Sensing

Discriminant analysis

Reflectance technique for predicting soil organic matter

Soil Science Society of America Journal

Assessing Reclamation Levels of Coastal Saline Lands with Integrated Stepwise Discriminant Analysis and Laboratory Hyperspectral Data¹