The availability of native phosphorus (P) in Northeast Indian Ultisols, one of the dominant agricultural soils in the region, is relatively low. Given that crop production in North Eastern region is dominated by low external input practices, native P remains important to plant P nutrition in many locations. A laboratory experiment was conducted in the College of Post Graduate Studies in Agricultural Sciences, Umiam, Meghalaya. The surface soil samples of 3 soil profiles were used in the study representing the soil order Ultisol. The physical and chemical attributes of the 3 profile soils along with the ability of the profiles to fix phosphorus (P) were determined in this investigation. The order Ultisol comprised of 3 profiles viz., P1, P2 and P3 representing North-West-1 Jorhat (Assam), Mokokchung (Nagaland) and North-West-2Jorhat (Assam), respectively. Results from the incubation experiment (Plevels 0, 25, 50, 100, 200, 300,400, 500, 600, 700 and 800 ppm for 24 h) indicated that phosphorus fixation capacity (PFC) (µg P g^-1 soil) ranged from 103 to 577 for the soil profiles of Ultisol. The maximum PFC was obtained at the P application dose (µg g^-1 soil) for Mokokchung (Nagaland) at 600.The higher percent P fixed was in order of Mokokchung, Nagaland (96.1) >North-West-2Jorhat, Assam (84.3)>North-West-1Jorhat, Assam (51.4). The bulk density (BD), maximum water holding capacity (MWHC) and clay content ranged from 0.95 to 1.16 g cc^-1, 36.0 to 54.9% and 10 to 55%, respectively among the three soil profiles. The content of soil organic carbon (SOC), soil available nitrogen, phosphorus and potassium (Avl.N, Avl.P and Avl.K, respectively) ranged from 1.0 to 2.0%, 176 to 216 kg ha^-1, 7.6 to 62.1 kg ha^-1and 108 to 205 kg ha^-1, respectively. Soil pH, exchangeable aluminium (Ex.Al), readily soluble aluminium (RS.Al), exchangeable calcium+magnesium (Ex.Ca+Mg) and base saturation (BS) ranged from 4.2 to 4.5, 0.46 to 2.81meq 100g^-1 soil, 34.6 to 384 mg kg^-1 soil, 1.7 to 2.10meq 100g^-1 soil, 16.2 to 30.2%, respectively. The soils of Mokokchung (Nagaland) showed the highest percentage of P fixation andNorth-West-1Jorhat (Assam), the least among the three profiles. It is utmost important to enhance the phosphorus use efficiency of these soils, which can be accomplished with the application of phosphatic fertilizers judiciously as the P reserves are depleting rapidly.

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