The insect data of 93 national nature reserves in China was used to identify the underlying drivers’ potential for species richness along geographical gradients. We assessed the correlations between predictors (climate and soil) and response variables (insect richness). We found that the following: insect diversity decreased significantly at higher latitudes. The latitudinal variation in insect richness seems to be driven by climate and soil variations and also the diversity of other biota. Among all the tested predictors, plant diversity explained the most latitudinal patterns of insect richness (R² = 0.498). Insect richness showed a positive correlation with the diversity of other biota and climate factors (mean annual temperature and mean annual precipitation) and was negatively associated with soil pH. Overall, the interspecific relationship between organisms was the main driver of insect diversity’s latitudinal pattern. However, the effects of climate and soil factors cannot be ignored.

Vegetation is a fundamental component of ecosystems and plays a vital role in maintaining ecological processes. It contributes to soil conservation, climate regulation, and landscape quality. Kunming, widely known as the “Spring City,” relies heavily on vegetation to sustain its ecological and social environment. This study employs moderate resolution imaging spectroradiometer (MODIS) and Normalized Difference Vegetation Index (NDVI) data in combination with temperature, precipitation, population, and gross domestic product (GDP) records to analyze the spatiotemporal dynamics and driving factors of NDVI-derived vegetation index in Kunming from 2000 to 2020 using trend and correlation analyses. We derived fractional vegetation coverage (FVC) from MODIS NDVI using the pixel dichotomy model, analyzed its temporal trends with linear regression, and applied pixel-wise Pearson correlation analysis to identify the spatial relationship between FVC and precipitation. The main findings can be summarized as follows: (1) The NDVI-derived vegetation index pattern in Kunming is generally higher in the west than in the east and higher in mountainous areas than in plains and basins. From 2000 to 2020, overall NDVI-derived vegetation index increased, with the mean NDVI rising from 0.48 to 0.545. Notably, the NDVI values in 2010 and 2012 declined sharply, likely due to drought conditions caused by reduced rainfall in the preceding years. (2) During the study period, 26.86% of the area showed moderate (NDVI slope: 0.005–0.016) improvement and 10.35% showed significant (NDVI slope: 0.016–0.063) improvement, while 10.28% exhibited degradation. Spatially, improvements were concentrated in Xundian County, parts of Dongchuan District, northern Luquan County, and northern border areas adjoining Yiliang and Shilin Counties. Areas with clear degradation were primarily located in Kunming’s main urban area and along the corridor from the airport to Songming. (3) Correlation analysis revealed that 53.3% of areas exhibited a positive relationship between temperature and NDVI-derived vegetation index, while 18.6% showed a significant negative correlation, mainly in the lower Pudu River basin, the Fumin–Luquan border, and the basin areas of Songming and Shilin Counties. This negative relationship may be attributed to increased evapotranspiration under higher temperatures, which exacerbates soil moisture loss and imposes drought stress on vegetation, thereby inhibiting plant growth. Similarly, 53% of areas showed a positive correlation between precipitation and FVC, whereas only 8.3% showed a significant negative correlation, underscoring the strong influence of precipitation on vegetation dynamics in Kunming. (4) Over the past two decades, Kunming’s GDP increased tenfold. In comparison with NDVI-derived vegetation index data for the same period, this indicates that areas of higher GDP are often associated with lower NDVI-derived vegetation index.

The elevational divergence of plant CSR (Competitor–Stress-Tolerator–Ruderal) strategies represents a core theme in global change ecology, yet adaptive patterns across subalpine transition zones remain insufficiently understood. This study focused on 375 plant individuals sampled along an 1143–4361 m elevational gradient on Gongga Mountain. We divided elevations into three zones (low, mid, high) using tertile partitioning, measured leaf functional traits including leaf area (LA), specific leaf area (SLA), and leaf dry matter content (LDMC), and quantified CSR strategy scores with the StrateFy approach. We further explored how hydrothermal factors drive community- and intraspecific-level strategy variation. Results showed that CSR strategies differed significantly along the elevational gradient. The relative abundance of individuals with the C strategy was 53.4% at low elevations, peaked at 72.4% at mid elevations, and decreased to 43.6% at high elevations. By contrast, the S strategy was most abundant at high elevations (32.5%), while the R strategy consistently accounted for less than 5% across all zones. Life form-specific strategies varied strongly: herbs maintained a dominant C strategy (66.7%) at high elevations; trees shifted to S strategy dominance (60%) at high elevations; and shrubs displayed a balanced C–S strategy. Intraspecific plasticity in CSR strategies was pronounced: with increasing elevation, the dominant strategy shifted from C (33.3%) to S (66.7%), with a greater magnitude of variation than at the community level. Temperature was positively correlated with the C strategy (p < 0.001, R² = 0.53) and negatively correlated with the R strategy (p < 0.001, R² = 0.40). Precipitation was negatively correlated with the C strategy (p = 0.001, R² = 0.54) and positively correlated with the R strategy (p = 0.005, R² = 0.42), whereas both factors exerted weak effects on the S strategy. Our findings highlight that shifts in hydrothermal conditions are the primary drivers shaping CSR strategy distributions, and coordinated leaf trait variation serves as a key adaptation mechanism. These results improve mechanistic understanding of mountain plant adaptation and provide a scientific basis for alpine vegetation conservation and management.

Plant phenology is a sensitive indicator of ecosystem responses to climate change, yet its dynamics and drivers in subtropical montane forests remain poorly understood. Based on the continuous phenological monitoring of 12 dominant tree species from 2008 to 2022 in a mid-subtropical evergreen broad-leaved forest on Ailao Mountains, China, this study analyzed phenological shifts and their climatic drivers. The results show that, (1) unlike the widely reported trends in northern mid-to-high latitudes, spring phenophases (budburst and leaf-out) did not exhibit significant advancing trends, while autumn phenophases (leaf coloration and fall) remained stable; (2) water availability played a dominant role in regulating spring phenology, with both budburst and leaf-out showing significant negative correlations with winter-spring precipitation, and responses varied significantly across hydrological year types; and (3) the life form strongly influenced phenological strategies, with evergreen species exhibiting earlier spring phenology than deciduous species. This study highlights that in seasonally humid subtropical montane forests, water availability exerts a stronger control on phenology than temperature. Our findings underscore the necessity of incorporating precipitation variability and functional trait differences into assessments of forest phenology and ecosystem functioning under future climate change, providing a scientific basis for the conservation and adaptive management of subtropical forests.

Frequent co-occurrences of high temperature and drought in tropical regions make heat and drought tolerance of landscape plants core physiological traits that determine their landscape adaptability and community stability. However, systematic elucidation of the differentiation patterns of stress resistance between specialist and generalist tropical landscape plant species, the intrinsic correlations between heat and drought tolerance traits, and the regulatory mechanisms of leaf functional traits remains lacking. In this study, eight typical tropical landscape plant species in Xishuangbanna Tropical Botanical Garden were selected as research objects. By determining leaf chlorophyll fluorescence parameters, water relation parameters and leaf functional traits, we systematically analyzed the differences in heat and drought tolerance and interspecific differentiation characteristics between specialist and generalist species, and simultaneously elucidated the correlation patterns of drought-heat tolerance traits as well as the regulatory effects of leaf functional traits on these traits. The results showed that the turgor loss point water potential (Ψ_TLP) of generalist tropical landscape plant species was significantly higher than that of specialist species, with superior drought tolerance; in contrast, the half-lethal temperature of photosystem II (T50) of specialist species was significantly higher than that of generalist species, with stronger heat tolerance. Among the eight tested species, Bombax ceiba exhibited the strongest drought tolerance, while Baccaurea ramiflora had the optimal heat tolerance. The study also found that the drought and heat tolerance traits of tropical landscape plants exhibited stress-specific trade-offs; leaf functional traits had limited overall explanatory power for the stress resistance of tropical landscape plants and only exerted a certain regulatory effect on drought tolerance. This study clearly reveals the differences in heat and drought tolerance between specialist and generalist species. This finding not only enhances our mechanistic understanding of stress resistance in tropical plants but also provides data support for ecological restoration and conservation practices in tropical gardens.