Investigation of the ammonium fixation onto two typical Sabah paddy soils

Ann Anni Basik (2005) Investigation of the ammonium fixation onto two typical Sabah paddy soils. Universiti Malaysia Sabah. (Unpublished)


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The first step into balance fertilisation implementations in Sabah lowland paddy is by investigating the proportion of fixed NH4+ during submergence of paddy soils. In this research, the influences of flooding on the NH4+ fixation of two types of surface soils (0 to 30 cm), flooded and unflooded soils were investigated. The adsorption isotherm demonstrates a quadratic increase in NH4+ adsorption from 0 to 80 ug ml-1, with increments of equilibrium NH4+ concentration up to the range of 15 to 30 ppm. Adsorption coefficient, .Kd values calculated from the Freundlich equation, showed a more pronounced NH4+ adsorption capacity in unflooded soils (3 .17ugml-1) compared to flooded soils (1.44 ug ml-1) with a slightly higher adsorption capacity for both conditions of Papar soils in contrast to Tuaran soils. This study indicates that NH4+ adsorption capacity in unflooded soils is 2- to 3-folds higher compared to flooded soils. These data suggests that, N-fertiliser input should be lower in unflooded soils.

Item Type: Academic Exercise
Uncontrolled Keywords: fertilisation, paddy soil, influence of flooding, ammonium fixation
Subjects: Q Science > QD Chemistry
T Technology > TX Home economics > Nutrition. Foods and food supply
Divisions: SCHOOL > School of Science and Technology
Date Deposited: 11 Jul 2013 05:59
Last Modified: 23 Oct 2017 07:06

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