Effect of canal blocking on biodiversity of degraded peatlands: Insight from West Kalimantan

PLOS One | https://doi.org/10.1371/journal.pone.0334014 October 8, 2025 9 / 23 indicating differences between habitats (S9 Table). The following pairwise test showed that forest and non-forest pattern was apparent across bioacoustic factors (Fig 5). The value of ADI, AEI, and BI in disturbed peat forest has similarity with less disturbed peat forest, while disturbed wet shrub similar with estate crop. In addition, those third acoustic indices in forested habitat show differences with non-forested habitat. For the regression model, fixed effects included temperature, canopy cover, ground cover, number of tree individuals, and Shannon diversity of plants, while random effects include month, habitat types, recorder position (start and end tran- sect), and transect code. We did not include humidity as a predictor due to its high value in collinearity with temperature. Among all variables, ACI does not result any significant p-value (Fig 6). ADI is correlated with temperature and Shannon diversity of plant. AEI is correlated with temperature and canopy cover. BI is correlated with temperature. Habitat features In total, we documented 194 vascular plant species, comprising both woody trees and understory vegetation such as her- baceous plants, ferns, vines, shrubs, lianas, and grasses, with a total count of 2,845 individuals. Tree growth stages, rang- ing from seedling to mature trees, were observed across disturbed peat forests, less disturbed peat forests, and disturbed

wet shrub, while only seedlings were noted in estate crop areas (S13 Fig). Understory vegetation was found in all habitat types. However, a notable number of understoreys were observed in non-forested areas (estate crops and disturbed wet shrub) with peatland-typical undergrowth species such as Nephrolepis biserrata (ferns, n = 140 in estate crop, n = 176 in wet shrub), Pteridium esculentum (ferns, n = 19 in estate crop, n = 132 in wet shrub), and Stenochlaena palustris (ferns, n = 55 in estate crop, n = 170 in wet shrub) becoming dominant species inhabiting non-forested areas. The undergrowth species were different in disturbed peat forests, where although Nephrolepis biserrata (n = 22) remains the most abundant species, others such as Freycinetia angustifolia (liana, n = 18), Hanguana sp. (herb, n = 15), and Nepenthes ampullaria (liana, n = 10) were also abundant. Understory species found in disturbed peat forests were observed in very low numbers in less disturbed peat forests. Fig 4. GLM result of wildlife attributes. Column showing predictors while rows showing explanatory factors. https://doi.org/10.1371/journal.pone.0334014.g004