About Us | Help Videos | Contact Us | Subscriptions
 

Abstract

 

This article in JEQ

  1. Vol. 39 No. 1, p. 5-15
     
    Received: Jan 23, 2009
    Published: Jan, 2010


    * Corresponding author(s): dbundela@cssri.ernet.in
 View
 Download
 Alerts
 Permissions
 Share

doi:10.2134/jeq2009.0032

Remote Sensing and Geographic Information System for Appraisal of Salt-Affected Soils in India

  1. Gurbachan Singha,
  2. D. S. Bundela *a,
  3. Madhurama Sethib,
  4. Khajanchi Lalb and
  5. S. K. Kamraa
  1. a Gurbachan Singh, Director Division of Irrigation and Drainage Engineering
    b Divison of Soil and Crop Management, Central Soil Salinity Research Institute, Karnal 132001 India

Abstract

Quantification of the nature, extent, and spatial distribution of salt-affected soils (SAS) for India and the world is essential for planning and implementing reclamation programs in a timely and cost-effective manner for sustained crop production. The national extent of SAS for India over the last four decades was assessed by conventional and remote sensing approaches using diverse methodologies and class definitions and ranged from 6.0 to 26.1 million hectares (Mha) and 1.2 to 10.1 Mha, respectively. In 1966, an area of 6 Mha under SAS was first reported using the former approach. Three national estimates, obtained using remote sensing, were reconciled using a geographic information system, resulting in an acceptable extent of 6.73 Mha. Moderately and severely salt-encrusted lands having large contiguous area have been correctly mapped, but slightly salt-encrusted land having smaller affected areas within croplands has not been accurately mapped. Recent satellite sensors (e.g., Resourcesat-1, Cartosat-2, IKONOS-II, and RISAT-2), along with improved image processing techniques integrated with terrain and other spatial data using a geographic information system, are enabling mapping at large scale. Significant variations in salt encrustation at the surface caused by soil moisture, waterlogging conditions, salt-tolerant crops, and dynamics of subsurface salts present constraints in appraisal, delineation, and mapping efforts. The article provides an overview of development, identification, characterization, and delineation of SAS, past and current national scenarios of SAS using conventional and remote sensing approaches, reconciliation of national estimates, issues of SAS mapping, and future scope.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © 2010. American Society of Agronomy, Crop Science Society of America, Soil Science SocietyAmerican Society of Agronomy, Crop Science Society of America, and Soil Science Society of America