Factor analysis applied to fire temperature effects on water quality

Paulo Pereira, Xavier Úbeda, Luis Outeiro, Deborah A. Martin

Research output: Chapter in Book/Report/Conference proceedingChapter

11 Citations (Scopus)


Factor analysis is an excellent tool to reduce large data sets to an interpretable size. The aim of this work is to analyze the effects of fire temperature on the chemistry of ash slurries. Leaf litter from Quercus suber (Q.S), Quercus robur (Q.R) and Pinus pinea (P.P), collected in the northeast part of the Iberian Peninsula (Catalonia), was subjected to different temperatures (150°, 200°, 250°, 300°, 350°, 400°, 450°, 500° and 550°C) for 2 hours in a laboratory experiment. The total CaCO3 (in %) in the ash that resulted from each temperature treatment was estimated. Ash was mixed with distilled water to create a slurry in which the following parameters were measured: pH, electrical conductivity (EC), major elements (Ca2+, Mg2+ and Na+), minor elements (Al3+, Fe2+, Mn2+ and Zn2+) and other components (SiO2and P2O5). A previous analysis of the correlation coefficient between the elements analysed in each specie showed that in general, pH, EC and CaCO3 a good correlation with temperature gradient and negative with the minor elements in study. Using factor analysis, five factors explained a total of 96.10% of the variance. The results show that Factor 1 has high positive loadings for the pH, EC, and CaCO3 of the ash for all three plant species, and Na+ from Q.S and P.P, and high negative loadings for Al3+, Fe2+, Mn2+ of Q.S and Al3+ and Fe2+ of P.P. Factor 2 has high positive loadings for the major elements of Q.R, Q.S and P.P (except the Na+ in the last two plant species and Ca2+ in P.P) and P2O5 in Q.S. Factor 3 explains the other elements in Q.R and P.P and Ca2+ in P.P. Factor 5 only explains Zn2+ in P.P and Q.R. Analyzing factor scores, it is observed that the elements with negative values in Factor 1 are present in high quantities at 250-300 °C, and the elements with positive values are present at >450 °C. The elements in Factor 2 are more soluble at 400°C, in Factor 3 at 350°C, in Factor 4 at 200°C and in Factor 5 at 150°C. The solubilization of the elements varies among the ash from the three plant species, in addition to the pH value or the quantity of CaCO3 . These results have important implications for the effects of fire on water quality, which is a function of the plant species burned and the temperatures reached during the fire.

Original languageEnglish
Title of host publicationForest Fires: Detection, Suppression and Prevention
PublisherNova Science Publishers, Inc.
Number of pages14
ISBN (Print)9781607417163
Publication statusPublished - 2009
Externally publishedYes



  • Ash
  • Fire
  • Pinus pinea
  • Quercus robur
  • Quercus suber
  • Water quality

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Pereira, P., Úbeda, X., Outeiro, L., & Martin, D. A. (2009). Factor analysis applied to fire temperature effects on water quality. In Forest Fires: Detection, Suppression and Prevention (pp. 273-286). Nova Science Publishers, Inc..