Role of Nanoclays in Carbon stabilization in Andisols and Cambisols

• M Calabi-Floody ^[1] ; C Rumpel ^[4] ; G Velásquez ^[1] ; A Violante ^[2] ; R Bol ^[5] ; L. M Condron ^[3] ; M.L Mora ^[1]
  1. [1] Universidad de La Frontera

     Universidad de La Frontera

     Temuco, Chile

     
  2. [2] University of Naples Federico II

     University of Naples Federico II

     Nápoles, Italia

     
  3. [3] Lincoln University

     Lincoln University

     Nueva Zelanda

     
  4. [4] CNRS IEES
  5. [5] Institute of Bio- and Geosciences

  Mostrar afiliaciones +
• Localización: Journal of soil science and plant nutrition, ISSN-e 0718-9516, ISSN 0718-9508, Vol. 15, Nº. 3, 2015, págs. 587-604
• Idioma: inglés
• Enlaces
  • Texto completo
• Resumen

  • Greenhouse gas (GHG) emissions and their consequent effect on global warming are an issue of global environmental concern. Increased carbon (C) stabilization and sequestration in soil organic matter (SOM) is one of the ways to mitigate these emissions. Here we evaluated the role of nanoclays isolated from soil on C stabilization in both a C rich Andisols and C depleted Cambisols. Nanoclays were analyzed for size and morphology by transmission electron microscopy, for elemental composition and molecular composition using pyrolysis-GC/MS. Moreover, nanoclays were treated with H2O2 to isolate stable SOM associated with them. Our result showed better nanoclay extraction efficiency and higher nanoclay yield for Cambisol compared to Andisols, probably related to their low organic matter content. Nanoclay fractions from both soils were different in size, morphology, surface reactivity and SOM content. Nanoclays in Andisols sequester around 5-times more C than Cambisols, and stabilized 6 to 8-times more C than Cambisols nanoclay after SOM chemical oxidation. Isoelectric points and surface charge of nanoclays extracted from the two soils was very different. However, the chemical reactivity of the nanoclay SOM was similar, illustrating their importance for C sequestration. Generally, the precise C stabilization mechanisms of both soils may be different, with nanoscale aggregation being more important in Andisols. We can conclude that independent of the soil type and mineralogy the nanoclay fraction may play an important role in C sequestration and stabilization in soil-plant systems.