Forest Type, Bark Wounding, and Tapping: Their Combined Influence on Bacteria Biota of Styrax Paralleloneurus in Natural and Community Forest

Abstract

Styrax paralleloneurus is a resin-producing tree native to Sumatra, Indonesia. This study investigated the effects of tapping, bark wounding and forest type on bacterial biota in the stem of styrax in natural and community forests. Amplicon metagenomic sequencing of the 16S rRNA region was deployed to identify the bacterial communities associated with tapped and untapped trees across various environmental and experimental conditions. The results of the study showed that tapped trees had lower abundance and diversity of Pseudomonas compared to untapped trees, largely due to their increased exposure to external microbe communities and environmental elements. Serratia and Pantoea were more abundant in natural forest than community forest, while Bradyrhizobium lablabi was found abundantly in untapped trees. Additionally, the taxonomic analysis revealed distinct responses of bacterial genera to tapping and forest type, indicating that community forests could play a significant role in promoting biodiversity in forest ecosystems. This finding underscores the importance of community forests in biodiversity conservation. These insights can inform future conservation and management strategies to enhance biodiversity and underscore the need for sustainable forest management practices to maintain forest health and productivity.

Keywords: Styrax paralleloneurus; bacteria; biodiversity; forests; next‐generation sequencing.

FIGURE 1

The part of the plant which was sampled. Untapped tree from community forest (A), the untapped tree from the natural forest (B), wounded bark of the tapped tree from community forest (C), wounded bark of the tapped tree from the natural forest (D), unwounded bark of the tapped tree from community forest (E), unwounded bark of the tapped tree from natural forest (F).

FIGURE 2

Alpha Diversity Unwounded and Wounded Bark. (A) ACE (Abundance‐based Coverage Estimator): Estimates species richness based on rare species observed in the sample; (B) Chao1: A non‐parametric estimator of species richness, emphasising rare taxa. (C) Evenness: Reflects the relative distribution of species abundances within the community. (D) Observed OTUs (OB): The actual count of operational taxonomic units (OTUs) identified in the samples. (E) Shannon Index: Measures species diversity, accounting for both abundance and evenness of the species present. (F) Simpson Index: Indicates species dominance, with lower values representing higher diversity. *p < 0.05 (significant at the 5% level), **p < 0.01 (significant at the 1% level).

FIGURE 3

Beta Diversity visualised in Principal Coordinates Analysis (PCoA) (A) Unweighted UniFrac Distance (B) Weighted UniFrac Distance. (A) ACE (Abundance‐based Coverage Estimator): Estimates species richness based on rare species observed in the sample; (B) Chao1: A non‐parametric estimator of species richness, emphasising rare taxa. (C) Evenness: Reflects the relative distribution of species abundances within the community. (D) Observed OTUs (OB): The actual count of operational taxonomic units (OTUs) identified in the samples. (E) Shannon Index: Measures species diversity, accounting for both abundance and evenness of the species present. (F) Simpson Index: Indicates species dominance, with lower values representing higher diversity.

FIGURE 4

Heatmap of microbial species clusters (A = untapped tree, never wounded, community forest; B = untapped tree, never wounded, natural forest; C = tapped tree, wounded bark, community forest; D = tapped tree, wounded bark, natural forest; E = tapped tree, unwounded bark, community forest; F = tapped tree, unwounded bark, natural forest).

FIGURE 5

Venn diagram of (A) Natural Forest and community forest and (B) Each sampling treatment of natural and community forest.

FIGURE 6

Taxonomic analysis of bacteria from community forest and natural forest. (A) from genus level, (B) from phylum level.