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Forest Ecosystems 2022, 9(6): 100081 https://doi.org/10.1016/j.fecs.2022.100081
Research Article | Open Access | Issue | Published: 16 December 2022

Analysing changes in spatial point patterns: A proposal using data from a forest thinning experiment

Show Author's Information Christian Salas-Eljatiba,b,c,*( ),  Joaquín Riquelme-Alarcóna,  Pablo J. Donosod,  Diego Poncee,  Daniel P. Sotof
Centro de Modelación y Monitoreo de Ecosistemas, Escuela de Ingeniería Forestal, Universidad Mayor, Santiago, Chile
Vicerrectoría de Investigación y Postgrado, Universidad de La Frontera, Temuco, Chile
Departamento de Silvicultura y Conservación de la Naturaleza, Universidad de Chile, Santiago, Chile
Instituto de Bosques y Sociedad, Universidad Austral de Chile, Valdivia, Chile
Corporación Nacional Forestal, Valdivia, Chile
Departamento de Ciencias Naturales y Tecnología, Universidad de Aysén, Coyhaique, Chile

* Corresponding author. Centro de Modelacion y Monitoreo de Ecosistemas, Escuela de Ingeniería Forestal, Universidad Mayor, Santiago, Chile.

Keywords:
Spatial heterogeneity, Spatial diversity, Marked-point process, Conspecific, Variable-density thinning, Nothofagus
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Salas-Eljatib C, Riquelme-Alarcón J, Donoso PJ, et al. Analysing changes in spatial point patterns: A proposal using data from a forest thinning experiment. Forest Ecosystems, 2022, 9(6): 100081. https://doi.org/10.1016/j.fecs.2022.100081
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Abstract Full text About this article

Spatial patterns reveal critical features at the individual and community levels. However, how to evaluate changes in spatial characteristics remains largely unexplored. We assess spatial changes in spatial point patterns by augmenting current statistical functions and indices. We fitted functions to describe unmarked and marked (tree size) spatial patterns using data from a large-scale silvicultural experiment in southern Chile. Furthermore, we compute the mingling index to represent spatial tree diversity. We proffer the pair correlation function difference before and after treatment to detect changes in the unmarked-point pattern of trees and the semivariogram-ratio to evaluate changes in the marked-point pattern. Our research provides a quantitative assessment of a critical aspect of forest heterogeneity: changes in spatial unmarked and marked-point patterns. The proposed approach can be a powerful tool for quantifying the impacts of disturbances and silvicultural treatments on spatial patterns in forest ecosystems.


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About this article

Analysing changes in spatial point patterns: A proposal using data from a forest thinning experiment

Show Author's information Christian Salas-Eljatiba,b,c,*( ), Joaquín Riquelme-Alarcóna, Pablo J. Donosod, Diego Poncee, Daniel P. Sotof
Centro de Modelación y Monitoreo de Ecosistemas, Escuela de Ingeniería Forestal, Universidad Mayor, Santiago, Chile
Vicerrectoría de Investigación y Postgrado, Universidad de La Frontera, Temuco, Chile
Departamento de Silvicultura y Conservación de la Naturaleza, Universidad de Chile, Santiago, Chile
Instituto de Bosques y Sociedad, Universidad Austral de Chile, Valdivia, Chile
Corporación Nacional Forestal, Valdivia, Chile
Departamento de Ciencias Naturales y Tecnología, Universidad de Aysén, Coyhaique, Chile

* Corresponding author. Centro de Modelacion y Monitoreo de Ecosistemas, Escuela de Ingeniería Forestal, Universidad Mayor, Santiago, Chile.

Abstract

Spatial patterns reveal critical features at the individual and community levels. However, how to evaluate changes in spatial characteristics remains largely unexplored. We assess spatial changes in spatial point patterns by augmenting current statistical functions and indices. We fitted functions to describe unmarked and marked (tree size) spatial patterns using data from a large-scale silvicultural experiment in southern Chile. Furthermore, we compute the mingling index to represent spatial tree diversity. We proffer the pair correlation function difference before and after treatment to detect changes in the unmarked-point pattern of trees and the semivariogram-ratio to evaluate changes in the marked-point pattern. Our research provides a quantitative assessment of a critical aspect of forest heterogeneity: changes in spatial unmarked and marked-point patterns. The proposed approach can be a powerful tool for quantifying the impacts of disturbances and silvicultural treatments on spatial patterns in forest ecosystems.

Keywords: Spatial heterogeneity, Spatial diversity, Marked-point process, Conspecific, Variable-density thinning, Nothofagus

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Publication history

Received: 30 June 2022
Revised: 22 November 2022
Accepted: 27 November 2022
Published: 16 December 2022
Issue date: December 2022

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© 2022 The Authors.

Acknowledgements

We thank a large number of research assistants for collaborating in the establishment of the permanent sample plots and ultimately the experiment, as well as to Tomás Riquelme who made Fig. S1. Finally, we thank the anonymous reviewers for providing extremely detailed comments on earlier versions of this paper.

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This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

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