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The leaf economics spectrum (LES) is the leading theory of plant ecological strategies based on functional traits, which explains the trade-off between dry matter investment in leaf structure and the potential rate of resource return, revealing general patterns of leaf economic traits investment for different plant growth types, functional types, or biomes. Prior work has revealed the moderating role of different environmental factors on the LES, but whether the leaf trait bivariate relationships are shifted across climate regions or across continental scales requires further verification. Here we use the Köppen–Geiger climate classification, a very widely used and robust criterion, as a basis for classifying climate regions to explore climatic differences in leaf trait relationships. We compiled five leaf economic traits from a global dataset, including leaf dry matter content (LDMC), specific leaf area (SLA), photosynthesis per unit of leaf dry mass (Amass), leaf nitrogen concentration (Nmass), and leaf phosphorus concentration (Pmass). Moreover, we primarily used the standardized major axis (SMA) analysis to establish leaf trait bivariate relationships and to explore differences in trait relationships across climate regions as well as intercontinental differences within the same climate type. Leaf trait relationships were significantly correlated across almost all subgroups (P < 0.001). However, there was no common slope among different climate zones or climate types and the slopes of the groups fluctuated sharply up and down from the global estimates. The range of variation in the SMA slope of each leaf relationship was as follows: LDMC–SLA relationships (from −0.84 to −0.41); Amass–SLA relationships (from 0.83 to 1.97); Amass–Nmass relationships (from 1.33 to 2.25); Nmass–Pmass relationships (from 0.57 to 1.02). In addition, there was significant slope heterogeneity among continents within the Steppe climate (BS) or the Temperate humid climate (Cf). The shifts of leaf trait relationships in different climate regions provide evidence for environmentally driven differential plant investment in leaf economic traits. Understanding these differences helps to better calibrate various plant-climate models and reminds us that smaller-scale studies may need to be carefully compared with global studies.

Ecosystem stability is essential for the sustainable provision of diverse ecosystem services. However, the factors that maintain ecosystem stability and their relative importance on the Tibetan Plateau, a region sensitive to climate change, remain unclear. Here, we combined data from ground-based biodiversity surveys at 143 sites from 2019 to 2021 with the temporal stability of ecosystems derived from remote sensing data from 2000 to 2020 to disentangle mechanisms of diversity–stability relationships. We further quantified the impact of biodiversity (taxonomic, functional, and phylogenetic diversity) and environmental context (spatial location, climate, and soil conditions) on temporal stability. Our results show that the stability of a typical ecosystem on the Tibetan Plateau is mainly regulated by environmental factors, and the environmental context can directly affect the stability of the ecosystem rather than indirectly through biodiversity. These findings are critical for adaptation measures and prioritizing conservation areas for future climate change scenarios.

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