DOI: 10.5061/dryad.ghx3ffbph
title: Elevational range-sizes and edaphic associations for plant species of the Mount Kinabalu region of Borneo (Sabah, Malaysia)

description: Identifying physical and ecological boundaries that limit where species
 can occur is important for predicting how those species will respond to
 global change. The island of Borneo encompasses a wide range of habitats
 that support some of the highest richness on Earth, making it an ideal
 location for investigating ecological mechanisms underlying broad patterns
 of species distribution. We tested variation in richness and range-size in
 relation to edaphic specialization and vegetation zone boundaries using
 3060 plant species from 193 families centered around the elevational
 gradient of Mt. Kinabalu, Borneo. Across species, average range-size
 increased with elevation, consistent with Rapoport’s rule. However, plants
 associated with ultramafic soil, which is low in nutrient and water
 availability and often has high concentrations of heavy metals, had larger
 range-sizes and greater richness than expected along the elevational
 gradient, as compared to a null model with randomization of edaphic
 association. In contrast, non-ultramafic species had smaller range-sizes
 and lower richness than expected. These results suggest that tolerance of
 resource limitation may be associated with wider range-sizes, whereas
 species intolerant of edaphic stress may have narrower range-sizes,
 possibly owing to more intense competition in favorable soil types. Using
 elevation as a predictor of average range-sizes, we found that piece-wise
 models with breakpoints at vegetation zone transitions explained species
 distributions better than models that did not incorporate ecological
 boundaries. The greatest relative increases in range-size with respect to
 elevation occurred mid-elevation, within the montane cloud forest
 vegetation zone. Expansion of average range-size across an area without
 physical boundaries may indicate a shift in ecological strategy and
 importance of biotic versus abiotic stressors. Our results indicate that
 elevational range-size patterns are structured by ecological constraints
 such as species’ edaphic association, which may limit the ability of
 species to migrate up or down mountains in response to climate change.
description: This dataset includes summary information on elevational
 range-sizes and edaphic associations for 3060 vascular plant species in
 Nothern Borneo, Malaysia, with an emphasis on the Mount Kinabalu region.
 Data was compiled from multiple sources, including the Sabah Parks
 herbarium data, GBIF, and botanical monographs. Efforts were made to
 standardize nomenclature used for "Family", "Genus",
 and "Species" dataset columns. Species occurance along an
 elevational gradient was summarized in columns for the number of
 observations ("obs" column, which is used as a metric of
 rarity), elevation minimum ("elev.min" column), elevation
 maximum ("elev.max" column), and elevational range-size
 ("extent" column, which is the values of elev.max minus
 elev.min). All elevation values refer to meters above sea-level (m a.s.l).
 Edaphic association  ("edaphic.association" column) is the
 qualtiative interpretation of the frequency of occurance for species on
 ultramafic soil, with three categories used (ultramafic specialist,
 ultramafic tolerant, non-ultramafic), based on information available from
 herbarium records or habitat decriptions. Updated
 dataset (dated 2022-02-07) includes addition of information on ~700
 species (majority were previously excluded species due to single occurance
 records) using additional GBIF data, as well as updates for nomenclature,
 values for elevation minimum and maximum, or other entries if needed.
 Refer to metadata document for details on changes and usage.
description: Values for species with only one observation or an extent of zero
 were not included in this dataset due to minimum sample size criteria for
 range-size estimates or edaphic association classification methods. Single
 observation species that were excluded may represent an estimated half of
 the species richness for the region, thus this dataset may under-represent
 rare or information limited species. Updated dataset
 (dated 2022-02-07) expands on the information available for previously
 excluded species; refer to metadata document for details on changes and
 usage.