Application of remote sensing for salinity based coastal land use zoning in Bangladesh

Abstract

Rising soil and water salinity is a major concern for coastal areas. Salt-water shrimp aquaculture is a land use mal-adaption to the rising salinity trend, and is contributing to the salinity expansion as well as lowering land productivity in the coastal areas of Bangladesh. This paper aims to propose a salinity-based land use zoning to restrict salinity expansion and to reduce land use conflicts. An integrated salinity detection technique combing field soil samples, a geographic information system and remote sensing were used. Subsequently, two determining factors of land suitability—soil salinity and distance from saline water sources—were used to identify zones for paddy/crop, mixed use and shrimp. The study districts witnessed rising salinity between 1990 and 2016, and thereby, decreasing suitable land are for paddy/crop by 20.96% of the agricultural area. The land suitability for paddy, mixed use and shrimp zones was found to be 51.88%, 29.36% and 18.76% of the study area, respectively. The proposed zoning strategy of this paper can be used as a quick and efficient tool for baseline information for integrated coastal zone management plan.