Influence of method of leaching and soil texture on sodium breakthrough curves
1988
Fahad, A.A. (Nuclear Research Centre, Baghdad (Iraq). Faculty of Agriculture and Biology, P.O. Box 765) | Al-Zubaidi, A.H. | Al-Ganimi, A.K. (Baghdad Univ., Baghdad (Iraq). Coll. of Agriculture)
Leaching of sodium in undisturbed columns of loam and clay loam soils was studied under continuous ponding (CP), intremittent ponding (IP), and simulated rain (SR). The soil columns were artificially salinized and Na-22 (carrier-free) was surface applied. Samples of effluent were daily collected during the leaching course (50-120 d) for measuring of Na-22 and EC. There were marked differences in shape and position of Na breakthrough curves indicating the importance of both method of leaching and soil texture in determining the leaching curves. Only 17 d were required for breakthrough of Na in the loam soil under CP in comparison with 70 and 86 d under SR and IP, respectively. These periods were either increased or decreased in the clay loam soil. The concentration of Na in the effluent approached a maximum when 2.2, 2.7 and 2.8 pore volumes of leaching water passed through the columns of the loam soil under SR, IP, and CP, respectively. Differences between SR and CP was narrowed in leaching of the clay loam soil. Logarithmic equations were obtained for EC and time of leaching or volume of effluent. Data of EC were in consistence with Na breakthrough curves
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