Phosphorus sorption index in humid tropical soils
| Autor: | João Arthur Antonangelo, Luís Reynaldo Ferracciú Alleoni, Murilo Rodrigues de Campos |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Total organic carbon
Chemistry Phosphorus Soil Science chemistry.chemical_element Soil science Sorption 04 agricultural and veterinary sciences Ultisol 010501 environmental sciences 01 natural sciences Adsorption Oxisol Environmental chemistry Soil water 040103 agronomy & agriculture 0401 agriculture forestry and fisheries Agronomy and Crop Science Entisol 0105 earth and related environmental sciences Earth-Surface Processes |
| Zdroj: | Soil and Tillage Research. 156:110-118 |
| ISSN: | 0167-1987 |
| DOI: | 10.1016/j.still.2015.09.020 |
| Popis: | The dynamics of phosphorus (P) in soils is strongly influenced by organic and inorganic solid phases, biological activity and environmental factors. Highly weathered soils naturally contain low levels of P available to plants and have high adsorption capacity. The maximum adsorption capacity of P ( S max ) has been widely used to evaluate the adsorption capacity of soil P. The P sorption index (PSI) is also used for evaluating the P adsorption capacity of soil from a single concentration of P and is an effective alternative in the estimation of maximum adsorption. We obtained the maximum capacity of P adsorption ( S max ) and the P sorption index (PSI) of 29 Brazilian soils with different chemical, physical and mineralogical attributes. The use of the PSI to estimate the adsorption of P in a long-term experiment was also evaluated. For S max , rates of 10, 25, 50, 100, 200 and 260 mg L −1 of P in 24 h of contact were used. For the PSI, soils were divided into groups because of the variation in their capacity to adsorb P, and each group received an optimal P rate: 200, 500, 1000, 1500 or 3000 mg L −1 of P. The periods of reaction assessed were 1, 3, 7, 21, 42, and 84 d. S max was affected by amounts of clay, Fe and Al oxides and organic carbon (OC), which ranged from 61.7 (Typic Haploxeralf) to 5459.5 mg kg −1 (Mollic Fluvaquent). In the PSI, the average percentage of P adsorbed at the end of the contact period (84 d) ranged from 23% to 49% of P that was mixed initially and was, on average, four times higher than their values after 1 d of contact. Oxisols, Alfisols and Gleysols had the highest values of PSI. On the other hand, Ultisols and Entisols had the lowest ones. The PSI behaved similarly to the S max , and the highest values were found in soils with high contents of clay, C, crystalline and poorly crystallized Fe and Al oxides. Furthermore, the PSI was higher in the 84th day, highlighting the influence of the period of contact on P adsorption. |
| Databáze: | OpenAIRE |
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