Total and DTPA-Extractable Fe, Mn, Cu and Zn Contents in Some Soils of Bangladesh

Thirty soil samples representing different parent materials of Bangladesh were studied for the distribution of total and DTPA-extractable zinc, copper, manganese and iron in the surface horizons. Total content of micronutrients in these soils was moderate to high and their content decreased from the younger to the older soils. But the total quantity of the above nutrients showed little variation in soils developed on similar parent materials. On the basis of DTPA-extractable micronutrients, zinc deficiency was widespread (13 out of 30 soils) in these soils, whereas the quantities of iron, manganese and copper were adequate. The DTPA-extractable zinc, copper, manganese and iron showed high correlations with their total amounts, indicating a genetic relationship of these soils with zinc, copper, manganese and iron.