Nitrogen Mineralization as Affected by the Addition of Pond Sediments and Bentonite Clay to a Sandy Soil under Different Moisture Regimes

The effect of addition of bentonite day and pond sediment, varying in their N contents, to a loamy sand soil under different moisture regimes, on the mineralization of nitrogen was studied under labortatory conditions. The amount of nitrogen mineralized was determined periodically. With the increase in the moisture level from 4 to 15% there was corresponding increase in nitrogen mineralized in both treated and untreated soils. Maximum mineralization of N occurred in soil treated with pond sediment followed by bentonite clay and the untreated soil at comparable moisture levels.

Mineralization potential and mineralization rate of soil increased when mixed with pond sediment and bentonite clay. However, pond sediment was found to be more effective because of its high nutrient status particularly organic matter and total N. The soil treated with pond sediment showed higher amount of mineralized nitrogen even at low soil moisture level (5% moisture).