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Nitrate (NO3-1) leaching from soils results in the lower soil fertility, reduced crop productivity and increased water pollution. The effects of bentonite clay mixed with various nitrogen (N) fertilizers on NO3-1 leaching from sandy soils haven't been extensively studied. Therefore, the present lysimetric study determined NO3-1 leaching from bentonite [0, 2 and 4% (m/m)] treated sandy soil under three N sources (calcium nitrate [Ca(NO3)2], ammonium chloride [NH4Cl], and urea [CO(NH2)2] at the rate of 300 kg N ha-1). Results showed that bentonite markedly reduced NO3-1 release in the leachate, while 4% bentonite retained higher NO3 in the soil. The NO3-1 leaching from sandy soil varied with N sources as Ca(NO3)2 > NH4Cl > (CO(NH2)2. At early stages of leaching, higher concentrations of NO3-1 were detected in leachate with both NH4Cl and Ca(NO3)2, but leaching of NO3-1 increased with urea at later leaching stages. The amount of total NO3-1 retained in soil was conversely related to the amount of NO3-1 in the leachate. This study indicated that soil amendment with bentonite could efficiently mitigate NO3-1 leaching from sandy soil and hence prevent N fertilizer losses and groundwater pollution. [ABSTRACT FROM AUTHOR]

Introduction Organ transplantation across a species barrier--xenotransplantation--has been attempted for over a century. Given the rapidly increasing gap between the organs required and those available for transplantation, over the last [...]