Syed Elahi, Dhaka Univ, Dept of Soil, Water and Environment, Dhaka, 1000, Bangladesh, M. S. Hussain, Dhaka University, Dept of Soil, Water and Environment, Dhaka Univ, Dhaka, 1000, Bangladesh, Hari Eswaran, USDA/NRCS Soil Survey Division, 1400 Independence Ave., SW, Washington, DC 20250, and M. M. Hoque, Soil Resources Development Institute, Khamar Bari Sarak, Farm Gate, Dhaka, 1217, Bangladesh.
The reconnaissance soil survey in Bangladesh identified 476 soil series and a general soil map of the country showing the distribution of soil associations is available. A first task in the current exercise was the conversion of this map to Soil Taxonomy. The criteria used in the definition of soil series in Bangladesh are different than that used by USDA Natural Resources Conservation Service and this introduced several problems in the conversion. An initial field assessment suggested the possibility that even the same soil series located in different parts of the country could belong to several classes. Despite these limitations, the final map shows the geographic patterns. This preliminary map will be used for several derivative data. Distinct physiographic provinces comprise the country and statistical information is provided showing the distribution of soils in each of the province. With the attribute information available for each polygon and employing Geographic Information Science, an assessment of land quality and impact of land management is also attempted. Parts of the country are subject to extreme drought and others to prolonged flooding. With a goal of determining the effects of such climatic extremes to soil conditions and land use, a first step is to define the kinds of soils that exist in these areas. The map will be refined over the next few years to become the basis for national assessments of factors affecting sustainability of agriculture.