Skip to main content

Advertisement

Log in

Sediment source apportionment following wildfire in an upland commercial forest catchment

  • Sediments, Sec 3 • Hillslope and River Basin Sediment Dynamics • Research Article
  • Published:
Journal of Soils and Sediments Aims and scope Submit manuscript

Abstract

Purpose

Wildfires can have major impacts on water scarcity and water quality linked to off-site transfer of polluting ash and nutrients. Understanding sediment sources in burnt landscapes can help to develop mitigation strategies, especially in catchments planted with introduced species that are prone to fire. We investigated sediment sources activated by post-fire rainfall in a small-forested catchment that was impacted by a severe wildfire. The aim was to use environmental radionuclides and elemental geochemistry as tracers to apportion sediment sources within burnt plantation systems.

Methods

Surficial (0–2 cm) topsoil (n = 9), sub-surficial (2–4 cm) topsoil (i.e. below the burnt layer; n = 8) samples from burnt hillslopes and forest roads (n = 5) and stream banks (n = 5) soil samples were taken in the Quivolgo catchment, El Maule region, Chile. Sediment samples (n = 9) were collected from behind a v-notched weir on three dates after the fire: May 2017, July 2017 and October 2017. Soil and sediment samples were analysed by gamma spectrometry and wavelength-dispersive X-ray fluorescence (WD-XRF) used to obtain tracer properties. These were evaluated visually and statistically to identify potential non-conservative tracers. Sediment apportionment was undertaken using the MixSIAR mixing model.

Results

The tracer selection procedure resulted in ten tracers being used for sediment apportionment. Tracer suitability was based on (i) weak and non-significant linear relationship between tracer concentrations and specific surface area (SSA) and soil organic matter (SOM), and (ii) conservative behaviour supported by the inclusion of sediment samples within source convex hull. Sediments from sub-surface layer (2–4 cm) were the dominant source during the first two periods contributing 55 ± 11 and 78 ± 10% respectively, whereas road contribution was only important in the last period (71 ± 14%). Apportionment showed a shift in sediment source (i.e. from forest roads to hillslopes) compared to a previous study in the same catchment before wildfire. The main driver of erosion was attributed to overland flow convergence and consequent rill erosion across burnt hillslopes.

Conclusion

The study demonstrated combined use of environmental radionuclides with elemental geochemistry for sediment apportionment within burnt forest plantations and highlighted a switch in predominant source (e.g. sub-surface burnt soil) activated by post-fire rainfall events. The findings in this research will help forest companies to develop strategies to reduce off-site impacts of sediment release after wildfire in forest plantations.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11

Similar content being viewed by others

References

Download references

Acknowledgements

We would like to dedicate this study to all people that lost their possessions during this wildfire that affected a vast territory in Central Chile. The authors also want to acknowledge the logistic support of Bioforest to perform the study in the Quivolgo catchment. Finally, we would like to acknowledge the valuable comments from the reviewers that greatly improved the quality of this manuscript.

Availability of data and material

The electronic supplementary material can be seen in the Supplementary information of this article.

Code availability

Not applicable.

Funding

This research in the Quivolgo catchment was supported and financed by Bioforest, Arauco.

Author information

Authors and Affiliations

Authors

Contributions

Enrique Muñoz-Arcos, Claudio Bravo-Linares, Ramón Bustamante-Ortega and William H. Blake contributed to the study conception and design. Material preparation, sampling, data collection and analysis were performed by Enrique Muñoz-Arcos, Claudio Bravo-Linares, Luis Ovando-Fuentealba, Ramón Bustamante-Ortega, Alejandra Castillo-Santana, Alicia Cuevas-Aedo and Alex Taylor. The first draft of the manuscript was written by Enrique Muñoz-Arcos and all authors commented on previous versions of the manuscript. All authors read and approved the final version of this manuscript.

Corresponding author

Correspondence to Claudio Bravo-Linares.

Ethics declarations

Conflict of interest

The authors declare no competing interests.

Additional information

Responsible editor: Hugh Smith

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

ESM 1

(PDF 496 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Muñoz-Arcos, E., Castillo, A., Cuevas-Aedo, A. et al. Sediment source apportionment following wildfire in an upland commercial forest catchment. J Soils Sediments 21, 2432–2449 (2021). https://doi.org/10.1007/s11368-021-02943-w

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11368-021-02943-w

Keywords

Navigation