| 01 Apr 2026
HDM-Plot: a plot dataset of plant communities across three-dimensional zonal vegetation in the Hengduan Mountains, southwestern China
Abstract. The Hengduan Mountains (HDM) constitute one of the world’s richest biodiversity regions and are designated as a top-tier priority for ecological conservation. Vegetation investigations can help with the design and implementation of biodiversity conservation in this region. Here we present the HDM-Plot, a plot-based vegetation dataset compiled from 314 plots surveyed during four campaigns between 2022 and 2024, spanning major vegetation types from lowland dry-hot valleys to alpine areas in altitudes of 754–4,932 m. Each plot records detailed species-level information, including scientific name, growth form, life form, abundance, plant height, diameter at breast height or at base, crown width, and coverage, along with geographic coordinates and hierarchical vegetation classification. In total, the dataset comprises 14,113 individual records belonging to 1,127 species from 379 genera and 117 families. The dominant families are Rosaceae (133 species), Ericaceae (93), Fabaceae (66), Asteraceae (63), and Fagaceae (37), and the dominant genera are Rhododendron (75), Berberis (34), Cotoneaster (30), Salix (24), and Quercus (22), with composition varying among vegetation types. Growth forms are mainly composed of shrubs (46.0 %), trees (27.3 %), and herbs (23.6 %). Herbs are dominated by perennial (92.1 %), shrubs are mainly deciduous broadleaf (59.7 %), and trees are primarily deciduous broadleaf (46.8 %) and evergreen broadleaf (41.6 %). Species richness exhibits a unimodal pattern with a mid-elevation peak, while growth forms and life forms show clear elevational changes. Floristically, temperate (54.1 %) and tropical (35.4 %) areal-types are predominant. 314 plots can be assigned to three vegetation formation groups, 18 vegetation formations, 142 alliance groups, 209 alliances, 238 association groups, and 299 associations. The HDM-Plot dataset provides an updated and standardized baseline for quantitative analyses of mountain vegetation, biodiversity assessment, and vegetation classification and mapping in southwestern China. Such information can be future used in the revisions of China’s vegetation classification scheme andVegegraphy of China. The dataset is available through the National Tibetan Plateau/Third Pole Environment Data Center (Jin et al., 2026; https://doi.org/10.11888/Terre.tpdc.303394).
This manuscript presents the HDM-Plot dataset, a plot-based vegetation dataset across the Hengduan Mountains region, comprising 314 plots sampled between 2022–2024 and covering a wide elevational gradient (754–4,932 m), with detailed species, structural, and environmental information. Overall, the dataset is valuable, timely, and potentially highly useful for studies of mountain biodiversity, vegetation classification, and macroecological analyses.
However, as a data paper, the manuscript still requires substantial revision to improve transparency in sampling design, clarify dataset scope, and strengthen technical validation and usability.
Major comments:
(1) One critical issue concerns the geographic extent of the dataset.
Based on Figure 1 and other maps throughout the manuscript, the spatial coverage—particularly in the southeastern part—clearly includes a substantial portion of the Yunnan–Guizhou (Yun–Gui) Plateau, rather than being restricted to the Hengduan Mountains sensu stricto. This has important implications for both the description and interpretation of the dataset.
Relatedly, the manuscript describes HDM vegetation as being dominated by subtropical evergreen broadleaf forests (Lines 73–74; light blue region in Fig. 1) and reports a relatively high proportion of tropical areal-types (35.4%; Line 24). These statements appear inconsistent with the widely accepted view that the Hengduan Mountains flora is predominantly temperate in character, within the Sino-Himalayan floristic region. While the HDM is indeed a transitional zone between tropical Southeast Asia and temperate East Asia, its floristic identity is generally shaped by temperate elements at mid–high elevations, with tropical components being comparatively limited and largely confined to lower elevations.
This discrepancy may arise from the inclusion of non-HDM areas (e.g., the Yun–Gui Plateau) in the dataset. I recommend that the authors explicitly clarify the sampling extent and adopt one of the following approaches: (1) restrict the dataset strictly to the Hengduan Mountains by removing sites appearently located on Yun-Gui Plateu & revise all corresponding maps and summaries, or (2) acknowledge that the dataset covers adjacent Plateau, revise the manuscript accordingly, and avoid presenting results as representative of the Hengduan Mountains alone.
In addition, Figure 2 appears to include several plots in the northwestern corner that fall outside the defined study region. The authors seems to include these plots in downstream analyses (and maps), and if so, apply a consistent treatment to all peripheral plots (including those in the southeastern plateau).
(2) The sampling design and representativeness
The manuscript states that plots were placed across representative mountains and valleys, while also considering logistics and accessibility. However, the sampling design remains insufficiently documented for a data paper -- there is no clear stratification scheme (by elevation / vegetation / region), potential accessibility bias is not quantified, and the overall sampling rationale remains unclear (representativeness, coverage of extremes, opportunistic survey). For transparency and future data reuse, the authors should clarify the sampling design rationale and goals. Additionally, the authors could provide a table or supplementary figures to show: (a) numbers of plots per vegetatin types (ideally alongside the relative area of each vegetation type in the study region); (b) numbers of plots per elevational band (e.g., 500-m intervals). These would be helpful information to interpret the data.
(3) Interpretation of ecological patterns
The manuscript reports patterns such as: unimodal richness along elevation and growth-form shifts across gradients. Given the non-random sampling design and uneven spatial distribution of plots, these results should be presented more cautiously. They are best interpreted as descriptive summaries of the dataset, rather than as general ecological conclusions about the Hengduan Mountains region. I recommend explicitly reframing these results to avoid overinterpretation.
(4) Figure elements
Several figures could be substantially improved in terms of clarity and presentation.
For example, multi-panel figures should include panel labels (e.g., a, b, c, d) to clearly separate different components. In Figure 1, the left panel could be (a) horizontal vegetation type distributions, and the right panel could be (b) elevational distribution. For Figure 3/4/5/6, there could be four pannels, (a) for spatial patterns of Families, (b) for genera, (c) for elevational patterns of Families, and (d) for genera. Similar suggestion for Figure 11. And figure captions need to be revised correspondingly.
For some figures, units are missing. Elevation units (“m”) should be explicitly indicated in Figure 1/2/3/4/5/6. Also, units for MAT (°C) and MAP (mm) are missing in Figure 2 and should be added
For Scatterplots by groups, such as elevational patterns of plots in Figure 3/4/5/6/11, though jittering helps to separate points, but many are overlayed due to the large amount. I recommend that these figures could be modified to volin plots to show the density of plots along elevation, which would better represent distribution patterns.
For Figure 7, since piecharts are not ideal (and largely redundant with numeric labels). Stacked barplots would provide clearer and more comparable information
Minor comments:
- Line 9: "investigations": investigation.
- Line 12: "in altitudes of 754–4,932 m": of/spanning altitudes of 754–4,932 m.
- Line 126: "The HDM cover...": The HDM covers ..., or The Hengduan Mountains cover...
- Line 254: “Along the ranges of elevation”: Across the elevational gradient, or Along the elevational range surveyed...
- Line 182: what is community height? How community height and total coverage are visually estimated in the field? Were standardized protocols used across observers to ensure consistency?
- “Abundance” is recorded (Line13), but it is unclear whether this refers to: counts, coverage, or others, across forest, shrubland, and grassland plots? The authors need to clarify this in the main text to explain how data collected behind Table 4.
- Table 3 is very long (nearly four pages) and would be better placed in the Supplementary Material or provided as part of the dataset rather than in the main text.