title: Remote Sensing Monitoring of Changes in Soil Salinity: A Case Study in Inner Mongolia, China.
abstract: This study used archived remote sensing images to depict the history of changes in soil salinity in the Hetao Irrigation District in Inner Mongolia, China, with the purpose of linking these changes with land and water management practices and to draw lessons for salinity control. Most data came from LANDSAT satellite images taken in 1973, 1977, 1988, 1991, 1996, 2001, and 2006. In these years salt-affected areas were detected using a normal supervised classification method. Corresponding cropped areas were detected from NVDI (Normalized Difference Vegetation Index) values using an unsupervised method. Field samples and agricultural statistics were used to estimate the accuracy of the classification. Historical data concerning irrigation/drainage and the groundwater table were used to analyze the relation between changes in soil salinity and land and water management practices. Results showed that: (1) the overall accuracy of remote sensing in detecting soil salinity was 90.2%, and in detecting cropped area, 98%; (2) the installation/innovation of the drainage system did help to control salinity; and (3) a low ratio of cropped land helped control salinity in the Hetao Irrigation District. These findings suggest that remote sensing is a useful tool to detect soil salinity and has potential in evaluating and improving land and water management practices.
authors.affiliation: State Key Laboratory of Water Resource and Hydropower Engineering Science, Wuhan University, Wuhan 430072, P.R. China. jingweifr@gmail.com.
authors.forename: Jingwei
authors.initials: J
authors.lastname: Wu
authors.affiliation: Cemagref, BP 44, 92163 Antony Cedex, France. bernard.vincent@cemagref.fr.
authors.forename: Bernard
authors.initials: B
authors.lastname: Vincent
authors.affiliation: State Key Laboratory of Water Resource and Hydropower Engineering Science, Wuhan University, Wuhan 430072, P.R. China. jzyang@whu.edu.cn.
authors.forename: Jinzhong
authors.initials: J
authors.lastname: Yang
authors.affiliation: Cemagref, 361 rue Jean-François Breton, BP 5095, 34196 Montpellier Cedex 5, France. sami.bouarfa@cemagref.fr.
authors.forename: Sami
authors.initials: S
authors.lastname: Bouarfa
authors.affiliation: Cemagref, 361 rue Jean-François Breton, BP 5095, 34196 Montpellier Cedex 5, France. alain.vidal@cemagref.fr.
authors.forename: Alain
authors.initials: A
authors.lastname: Vidal
keywords: Hetao Irrigation District; Remote sensing; changing soil salinity