Rafael, Rogério Borguete AlvesFernández Marcos, María LuisaCOCCO, StefaniaRuello, Maria LetiziaWeindorf, David C.Cardelli, ValeriaCORTI, Giuseppe2018-10-292019-08-052018-02Rafael, R. B. A., Fernández-Marcos, M. L., Cocco, S., Ruello, M. L., Weindorf, D. C., Cardelli, V., and Corti, G. (2018). Assessment of Potential Nutrient Release from Phosphate Rock and Dolostone for Application in Acid Soils. Pedosphere 28, 44-581002-0160http://hdl.handle.net/10347/17629This is the accepted manuscript of the following article: Rafael, R. B. A., Fernández-Marcos, M. L., Cocco, S., Ruello, M. L., Weindorf, D. C., Cardelli, V., and Corti, G. (2018). Assessment of Potential Nutrient Release from Phosphate Rock and Dolostone for Application in Acid Soils. Pedosphere 28, 44-58. doi: 10.1016/S1002- 0160(17)60437-5Finding alternative local sources of plant nutrients is a practical, low-cost, and long-term strategy. In this study, laboratory column experiments were conducted in a completely randomized design to evaluate the feasibility of using phosphate rock and dolostone as fertilizers or acid-neutralizing agents for application in tropical acid soils. The dissolution rates of different particle-size fractions (0.063–0.25, 0.25–0.5, and 0.5–2 mm) of both rocks were studied by citric acid solution at pH 4 and 2 and water, with extraction times of 1, 3, 5, 7, 12, 24, 72, 144, 240, and 360 h. The results showed that the dissolution of both rocks depended on the particle size, leaching solution, and extraction time. The dissolution rate of rock-forming minerals increased as the specific surface area increased, corresponding to a decrease in particle size. In all cases, the release kinetics was characterized by two phases: 1) a first stage of rapid release that lasted 24 h and would ensure short-term nutrient release, and 2) a second stage of slow release after 24 h, representing the long-term nutrient release efficiency. Both rocks were suitable as slow-release fertilizers in strongly acid soils and would ensure the replenishment of P, Ca, and Mg. A combination of fine and medium particle-size fractions should be used to ensure high nutrient-release efficiency. Much work could remain to determine the overall impact of considerable amounts of fresh rocks in soilseng© 2018 Soil Science Society of China Published by Elsevier B.V. and Science Press. This manuscript version is made available under the CC-BY-NC-ND 4.0 licensehttps://creativecommons.org/licenses/by-nc-nd/4.0/Citric acidDissolution rateLeaching solutionParticle-size fractionRelease kineticsSlow-release fertilizerMaterias::Investigación::25 Ciencias de la tierra y del espacio::2511 Ciencias del suelo (Edafología)journal article10.1016/S1002-0160(17)60437-5open access