This work reports an ultrasensitive wearable temperature sensor based on GNWs/PDMS for personalized healthcare and human–machine interface systems.

Clarifying the coordination of leaf hydraulic traits with gas exchange across closely-related species adapted to varying rainfall can provide insights into plant habitat distribution and drought adaptation. The leaf hydraulic conductance (K leaf), stomatal conductance (g s), net assimilation (A), vein embolism and abscisic acid (ABA) concentration during dehydration were quantified, as well as pressure-volume curve traits and vein anatomy in 10 Caragana species adapted to a range of mean annual precipitation (MAP) conditions and growing in a common garden. We found a positive correlation between Ψ leaf at 50% loss of K leaf (K leaf P 50) and maximum K leaf (K leaf-max) across species. Species from low-MAP environments exhibited more negative K leaf P 50 and turgor loss point, and higher K leaf-max and leaf-specific capacity at full turgor, along with higher vein density and midrib xylem per leaf area, and a higher ratio of K leaf-max : maximum g s. Tighter stomatal control mediated by higher ABA accumulation during dehydration in these species resulted in an increase in hydraulic safety and intrinsic water use efficiency (WUE i) during drought. Our results suggest that high hydraulic safety and efficiency combined with greater stomatal sensitivity triggered by ABA production and leading to greater WUE i provides drought tolerance in Caragana species adapted to low-MAP environments.

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Seed germination behavior is an important factor in the distribution of species. Many studies have shown that germination is controlled by phylogenetic constraints, however, it is not clear whether phylogenetic constraints or environmental cues explain seed germination of a genus from a common ancestor. In this study, seed germination under different temperature-and water-regimes [induced by different osmotic potentials of polyethylene glycol (PEG)] was investigated in the phylogeneticallyrelated Caragana species that thrive in arid, semiarid, semihumid and humid environments. The results showed that the final percentage germination (FPG) decreased from 95% in species from arid habitats to 0% in species from humid habitats, but with no significant phylogenetic signal. Rather, the response of seed germination to temperature and PEG varied greatly with species from arid to humid habitats and was tightly linked to the ecological niche of the species, their seed coat structure and abscisic acid concentration. The findings are not consistent with the hypothesis that within a family or a genus, seed germination strategies can be a stable evolutionary trait, thus constraining interspecific variation, but the results clearly show that seed germination of Caragana species distributed across a range of habitats has adapted to the environment of that habitat.The 'how and why' of plant species' distribution has been a subject of fundamental importance throughout the history of plant ecology 1 . Among several traits that account for species' distribution, the germination of the seed is a critical step in the life cycle of a plant 2-4 that is particularly vulnerable to environmental stress 3,5,6 . The most favorable period for seed germination of a species varies according to it's geographic distribution and life cycle 7,8 . Therefore, investigation of seed behaviour of species in response to a combination of biotic and abiotic factors may help to understand factors related to the distribution of the species 5 . Among biotic factors, it is considered that seed germination is genetically determined and the phylogenetic signal is a significant constraint, termed a phylogenetic constraint 6,9 , to the evolution and expression of seed traits. As a result of phylogenetic constraints, closely-related species do not move too far from their optimum niche and share similar seed-germination traits or niche preferences 6,9,10 . For example, when phylogenetic analysis is used to infer the evolution, there is strong evidence of phylogenetic constraints on seed size 11 . As seed size is positively correlated with mean time to germination, this suggests that seed germination is likely to be a phylogenetically-conserved trait 3 . Zhang et al. 6 found that closely-related species shared similar germination times (temporal niche preferences). Romulea species that grow in different Mediterranean habitats exhibit strong phylogenetic constraints on the phenology of seed germination regardless of their habitat of origin 12 , and species in North A...

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Plots in an alpine meadow fertilized with Si in combination with either N or P had higher aboveground primary productivity (APP) and higher species richness than when fertilized with N or P alone. Our finding highlights the importance of Si in improving APP and alleviating N fertilization-induced biodiversity loss in grasslands, and will help improve our ability to predict community composition and biomass dynamics in alpine meadow ecosystems subject to changing nutrient availability.

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