| Summary: | Excessive amounts of Na<sup>+</sup> and soluble salts are characteristics of saline-sodic soils. Loss of soil structure and osmotic stress in plants are negative effects of salinity-sodicity. This study evaluated the effect of cattle manure, biochar and tropical peat at 1 and 2% (<i>w</i>/<i>w</i>) with leaching, on the exchangeable sodium percentage (ESP), electrical conductivity (EC<sub>e</sub>) and pH of a saline-sodic soil from the High Valley of Cochabamba (Bolivia). The soil was placed in simulated soil columns and two lixiviations were applied. The initial values of soil were as follows: ESP of 66.6%, EC<sub>e</sub> of 20.5 dS m<sup>−1</sup>, and pH of 8.55. Results after leaching differed significantly (<i>p</i> = 0.05) among the interactions. Cattle manure at 2% was the most effective in reducing soil ESP to 27.6%, followed by the rest of the treatments. The three amendments at any level were efficient in lowering EC<sub>e</sub> below 4 dS m<sup>−1</sup>. Peat at 2% decreased the soil pH to 7.76. The superiority of cattle manure can be explained by the improvement of soil aggregation and leaching efficiency, through its OM and Ca<sup>2+</sup> + Mg<sup>2+</sup> contribution. Overall, cattle manure was superior in reclaiming the soil salinity-sodicity, and only the EC<sub>e</sub> threshold value from the US Salinity Lab classification was reached by any amendment, indicating that cattle manure, biochar or tropical peat with leaching, can be used to reclaim some saline-sodic soils.
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