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Variability of the quality and quantity of organic matter in soil affected by multiple wildfires

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Fire in mountainous areas can lead to increased variability of their soil organic matter (SOM) due to spatial inhomogeneity and pre-fire fuel distribution. Here, we elucidated if this was the case in our study area and how this affected the reliability of solid-state 13C NMR spectroscopy applied for the study of the medium-term impact of fire on SOM

Materials and methods

The study occurred in the Sierra de Aznalcóllar, Southern Spain, which experienced their last intense fire 7 years before sampling. In a first approach (method 1), the corners and the center of a randomly chosen square with a side length of 15 m were sampled and analyzed separately. For comparison, composite samples (method 2) were obtained from three soils. We characterized material from unburnt, burnt, and double burnt regions. Data describing the physical and chemical properties of the soils together with the NMR spectroscopic characterization were analyzed using ANOVA.

Results and discussion

Both sampling methods yielded comparable results with comparable standard errors. No major differences between the fire-affected and unburnt soils were observed with respect to physical and chemical properties and C and N contents, but solid-state 13C NMR spectroscopy indicated a small but significant elevation of aromaticity in the soils with fire history.


The analysis showed that sampling with reduced replicates (method 1) can still lead to representative NMR data. The more complex sampling of comparing three composite samples (method 2) did not decrease the standard error. Our results also indicate that in the study area typical properties of the soil and its SOM induced by former burnings will not persist beyond a few decades.

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  1. Almendros G, González-Vila FJ (2012) Wildfires, soil carbon balance and resilient organic matter in Mediterranean ecosystems. A review. Span J Soil Sci 2:8–33

  2. Andersson M, Michelsen A, Jensen M, Kjoller A (2004) Tropical savannah woodland: effects of experimental fire on soil microorganisms and soil emissions of carbon dioxide. Soil Biol Biochem 36:849–858

  3. Badía D, Martí C, Aguirre AJ, Aznar JM, González-Pérez JA, De la Rosa JM, León J, Ibarra P, Echeverría T (2014) Wildfire effects on nutrients and organic carbon of a Rendzic Phaeozem in NE Spain: changes at cm-scale topsoil. Catena 113:267–275

  4. Baldock JA, Oades JM, Vassallo AM, Wilson MA (1990) Solid state CP/MAS 13C N.M.R. analysis of particle size and density fractions of a soil incubated with uniformly labelled 13C-glucose. Aust J Soil Res 28:193–212

  5. Baldock JA, Oades JM, Nelson PN, Skene TM, Golchin A, Clarke P (1997) Assessing the extent of decomposition of natural organic materials using solid-state 13C NMR spectroscopy. Soil Res 35:1061–1084

  6. Braadbaart F, Poole I, van Brussel AA (2009) Preservation potential of charcoal in alkaline environments: an experimental approach and implications for the archaeological record. J Archaeol Sci 36:1672–1679

  7. Caon L, Vallejo VR, Coen RJ, Geissen V (2014) Effects of wildfire on soil nutrients in Mediterranean ecosystems. Earth Sci Rev 139:47–58

  8. Carter MC, Darwin Foster C (2004) Prescribed burning and productivity in southern pine forests: a review. Forest Ecol Manag 191:93–109

  9. Certini G (2005) Effects of fire on properties of forest soils: a review. Oecologia 143:1–10

  10. Certini G, Nocentini C, Knicker H, Arfaioli P, Rumpel C (2011) Wildfire effects on soil organic matter quantity and quality in two fire-prone Mediterranean pine forests. Geoderma 167–168:148–155

  11. De la Rosa JM, González-Pérez JA, González-Vila FJ, Knicker H (2013) Medium term effects of fire induced soil organic matter alterations on Andosols under Canarian pine (Pinus canariensis). J Anal Appl Pyrol 104:269–279

  12. Fakoussa RM, Hofrichter M (1999) Biotechnology and microbiology of coal degradation. Appl Microbiol Biotechnol 52:25–40

  13. Gómez-Rey MX, González-Prieto SJ (2014) Short and medium-term effects of a wildfire and two emergency stabilization treatments on the availability of macronutrients and trace elements in topsoil. Sci Total Environ 493:251–261

  14. Gonçalves CN, Dalmolin RSD, Dick DP, Knicker H, Klamt E, Kögel-Knabner I (2003) The effect of 10% HF treatment on the resolution of CPMAS 13C NMR spectra and on the quality of organic matter in Ferralsols. Geoderma 116:373–392

  15. González-Pérez JA, González-Vila FJ, Almendros G, Knicker H (2004) The effect of fire on soil organic matter—a review. Environ Int 30:855–870

  16. Guénon R, Vennetier M, Dupuy N, Ziarelli F, Gros R (2011) Soil organic matter quality and microbial catabolic functions along a gradient of wildfire history in a Mediterranean ecosystem. Appl Soil Ecol 48:81–93

  17. Inbar A, Lado M, Sternberg M, Tenau H, Ben-Hur M (2014) Forest fire effects on soil chemical and physicochemical properties, infiltration, runoff, and erosion in a semiarid Mediterranean region. Geoderma 221–222:131–138

  18. IUSS Working Group WRB (2014) World Reference Base for Soil Resources 2014. International soil classification system for naming soils and creating legends for soil maps. World Soil Resources Reports No. 106. FAO, Rome

  19. Kara O, Bolat I (2009) Short-term effects of wildfire on microbial biomass and abundance in black pine plantation soils in Turkey. Ecol Ind 9:1151–1155

  20. Keeney DR, Nelson DW (1982) Nitrogen in organic forms. In: Page AL, Miller RH, Keeney DR (eds) Methods of soil analysis, part 2. Agronomy American Society of Agronomy, Madison, pp 643–698

  21. Kloss S, Sass O, Geitner C, Prietzel J (2012) Soil properties and charcoal dynamics of burnt soils in the Tyrolean Limestone Alps. Catena 99:75–82

  22. Knicker H (2011) Solid state CPMAS 13C and 15N NMR spectroscopy in organic geochemistry and how spin dynamics can either aggravate or improve spectra interpretation. Org Geochem 42:867–890

  23. Knicker H, Lüdemann H-D (1995) N-15 and C-13 CPMAS and solution NMR studies of N-15 enriched plant material during 600 days of microbial degradation. Org Geochem 23:329–341

  24. Knicker H, González-Vila FJ, Polvillo O, González JA, Almendros G (2005a) Fire-induced transformation of C- and N- forms in different organic soil fractions from a Dystric Cambisol under a Mediterranean pine forest (Pinus pinaster). Soil Biol Biochem 37:701–718

  25. Knicker H, Totsche K-U, Almendros G, González-Vila FJ (2005b) Condensation degree of burnt peat and plant residues and the reliability of solid-state VACP MAS 13C NMR spectra obtained from pyrogenic humic material. Org Geochem 36:1359–1377

  26. Knicker H, Almendros G, González-Vila FJ, González-Pérez JA, Polvillo O (2006) Characteristic alterations of quantity and quality of soil organic matter caused by forest fires in continental Mediterranean ecosystems: a solid-state 13C NMR study. Eur J Soil Sci 57:558–569

  27. Knicker H, Müller P, Hilscher A (2007) How useful is chemical oxidation with dichromate for the determination of “Black Carbon” in fire-affected soils? Geoderma 142:178–196

  28. Knicker H, Hilscher A, González-Vila FJ, Almendros G (2008a) A new conceptual model for the structural properties of char produced during vegetation fires. Org Geochem 39:935–939

  29. Knicker H, Wiesmeier M, Dick DP (2008b) A simplified method for the quantification of pyrogenic organic matter in grassland soils via chemical oxidation. Geoderma 147:69–74

  30. Knicker H, González-Vila FJ, González-Vázquez R (2013) Biodegradability of organic matter in fire-affected mineral soils of Southern Spain. Soil Biol Biochem 56:31–39

  31. Li Y (2010) Can the spatial prediction of soil organic matter contents at various sampling scales be improved by using regression kriging with auxiliary information? Geoderma 159:63–75

  32. Martín A, Díaz-Raviña M, Carballas T (2012) Short- and medium-term evolution of soil properties in Atlantic forest ecosystems affected by wildfires. Land Degrad Dev 23:427–439

  33. Novara A, Gristina L, Bodì MB, Cerdà A (2011) The impact of fire on redistribution of soil organic matter on a Mediterranean hillslope under maquia vegetation type. Land Degrad Dev 22:530–536

  34. Núñez MA, Recio JM (2007) Kaolinitic paleosols in the south west of the Iberian Peninsula (Sierra Morena region, Spain). Paleoenvironmental implications. Catena 70:388–395

  35. Prieto-Fernández Á, Carballas M, Carballas T (2004) Inorganic and organic N pools in soils burned or heated: immediate alterations and evolution after forest wildfires. Geoderma 121:291–306

  36. Rumpel C, Alexis M, Chabbi A, Chaplot V, Rasse DP, Valentin C, Mariotti A (2006) Black carbon contribution to soil organic matter composition in tropical sloping land under slash and burn agriculture. Geoderma 130:35–46

  37. Vergnoux A, Di Rocco R, Domeizel M, Guiliano M, Doumenq P, Théraulaz F (2011) Effects of forest fires on water extractable organic matter and humic substances from Mediterranean soils: UV–vis and fluorescence spectroscopy approaches. Geoderma 160:434–443

  38. Wilson MA (1981) Applications of nuclear magnetic resonance spectroscopy to the study of soil organic matter. J Soil Sci 32:167–186

  39. Xu Y, Sun J, Lin Q, Ma J, Shi Y, Lou K (2012) Effects of a surface wildfire on soil nutrient and microbial functional diversity in a shrubbery. Acta Ecol Sin 32:258–264

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We acknowledge the Ministerio de Economía y Competitividad de España (MINECO) and the European Regional Development Fund (ERDF) for financial support (Project CGL2009-10557) and providing a travel grant to H. Knicker to visit the Institute of Bio- and Geosciences, Agrosphere (IBG-3), Forschungszentrum Jülich GmbH, Germany. The latter and here in particular, Dr. Anne Berns is gratefully acknowledged for providing access to the NMR facilities. The first author was financially supported by MINECO/ERDF (BES-2010-42581). Further, Samuel Manzano Moñino and Ignacio Villar Mavellán, from the “Centro de Plan Infoca y Centros de Defensa Forestal (CEDEFO), are greatly acknowledged for providing helpful information about the study area and their assistance during the field work. Juan de Dios Franco Navarro is thanked for his support during the statistical analysis. Garbriel Molina Candau, Serena Tabanera Rodrígrez, and the Company “Explotaciones Agrícolas, el Prado, S. L.” are acknowledged for allowing sampling on their property.

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Correspondence to María López-Martín.

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Responsible editor: Zhihong Xu

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López-Martín, M., Velasco-Molina, M. & Knicker, H. Variability of the quality and quantity of organic matter in soil affected by multiple wildfires. J Soils Sediments 16, 360–370 (2016).

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  • Medium-term fire effects
  • Pyrogenic organic matter
  • Sampling reliability
  • Solid-state 13C NMR spectroscopy
  • SOM characterization