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We report the effects of shifting cultivation on water quality in 16 creeks investigated once in 2007 and twice in 2008 in 16 apparently similar small neighboring watersheds, each of 3 to 5 ha, at four locations around Barkal sub-district under Rangamati District of Chittagong Hill Tracts in Bangladesh. Concentrations of SO₄ ²⁻ and K⁺, and pH in creek water were lower, and NO₃-N and Na⁺ concentrations were higher in shifting-cultivation land compared to land with either plantation or natural forest or a combination of these cover types. Shifting cultivation effects on some water quality parameters were not significant due to change in land cover of the watershed between two sampling periods either through introduction of planted tree species or naturally regenerated vegetation. Conductivity and concentrations of HCO₃ ⁻, PO₄ ³⁻, Ca²⁺ and Mg²⁺ in creek water showed no definite trend between shifting cultivation and the other land cover types. At one area near the Forest Range Office of Barkal, creek water pH was 5.8 under land cover with a combination of shifting cultivation and plantation. At this area Na⁺ concentration in shifting-cultivation land ranged from 32.33 to 33.00 mg·L⁻¹ and in vegetated area from 25.00 to 30.50 mg·L⁻¹ in 2007. At another area, Chaliatali Chara, SO₄ ²⁻ concentration in a shifting-cultivation watershed ranged from 4.46 to 10.51 mg·L⁻¹, lower than in a vegetated watershed that ranged from 11.69 to 19.98 mg·L⁻¹ in 2007. SO₄ ²⁻ concentration in this shifting-cultivation area ranged from 1.28 to 1.37 mg·L⁻¹ and in the vegetated area from 1.37 to 3.50 mg·L⁻¹ in 2008.
