Patterns of Density and Production in the Community Forests of the Sierra Madre Occidental, Mexico

Jaime Roberto Padilla-Martínez,Klaus V Gadow,Jaime Briseño-Reyes,Carola Paul,Pablito Marcelo López-Serrano,José Javier Corral-Rivas

doi:10.3390/f11030307

Abstract

The Mexican Sierra Madre Occidental (SMO) represents a region where hundreds of plant species reach the limits of their northern or southern range. The SMO also features a unique cultural diversity, and many communities living within the forest or in its close vicinity depend on the products and services that these forests provide. Our study was based on a large set of remeasured field plots placed in the forests of Durango which are part of the SMO. Using hierarchical clustering, three distinctly different forest types were identified based on structural differences and the relation between stem density and basal area. Maximum forest densities were estimated using a 0.975th quantile regression. Forest production (expressed as current periodic volume increment per unit of area and time) was estimated based on number of stems, forest density, mean height, and forest diversity. Forest density is the principal factors affecting periodic volume production. The discussion presented recommendations for the sustainable use of this unique natural resource. Maintaining minimum levels of residual density is key to ensuring the continued viability of the forests of the Mexican SMO. Future research is needed to identify optimum residual structures, productive residual densities, and desirable levels of biodiversity.

Highlights

Forest density is a multifaceted phenomenon, and the terminology relating to forest density is often the cause of misunderstanding
The results of this study did not reveal significant differences in tree diversity between well-defined field groups of plots that significantly differed in other site variables
Gadow et al [3] presented new retention strategies for selectively managed natural forests. They found that methods that do not prescribe how much to harvest but specify the residual forest in terms of tree species and dimensions, the structure, density, and diversity remaining after the harvest, were especially relevant

Summary

Introduction

Forest density is a multifaceted phenomenon, and the terminology relating to forest density is often the cause of misunderstanding. To prevent imprecise and confusing usage of the term, there is a need for clarification. We defined forest density as the degree of site occupancy by trees, i.e., the total tree biomass per unit forest area. It is almost impossible to assess that quantity. Basal area (the sum of the cross-sectional areas of the trees at breast height) is often used as a practical substitute for biomass. Forest density can be expressed in absolute or relative terms

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Conclusion