Heavy metal (HM) contamination resulting from industrialization and urbanization during the Anthropocene along with plant invasion can severely threaten the growth and adaptation of local flora. Invasive alien plant species generally exhibit a growth pattern consistent with their functional traits in non-contaminated environments in the introduced range. However, it remains unclear whether invasive alien plants have an advantage over native plants in contaminated environments and whether this growth pattern is dependent on the adaptation of their leaf functional traits. Here, we selected two congeneric pairs of invasive alien and native grasses that naturally co-exist in China and are commonly found growing in contaminated soil. To evaluate the effect of cadmium (Cd) on the structural and physiological leaf traits, we grew all four species in soil contaminated without or with 80 mg/kg Cd. Invasive plants contained significantly higher concentrations of Cd in all three organs (leaf, stem, and root). They displayed a higher transfer factor and bioconcentration factor (BCF) of shoot and root than natives, indicating that invasive species are potential Cd hyperaccumulators. Invasive plants accumulated polyphenol oxidase (PPO) to higher levels than natives and showed similar patterns of leaf structural and physiological traits in response to changes in Cd bioconcentration. The quantifiable leaf structural traits of invasive plants were significantly greater (except for stomatal density and number of dead leaves) than native plants. Leaf physiological traits, chlorophyll content, and flavonoid content were also significantly higher in invasive plants than in natives under Cd stress conditions after 4 weeks, although nitrogen balance index (NBI) showed no significant difference between the two species. Chlorophyll fluorescence parameters decreased, except for the quantum yield of photosystem II (ΦPSII) and the proportion of open photosystem II (qP), which increased under Cd stress conditions in both species. However, invasive plants exhibited higher fluorescence parameters than natives under Cd stress, and the decrement observed in invasive plants under Cd stress was greater than that in natives. High Cd adaptation of invasive grasses over natives suggests that invasive plants possess optimal leaf structural and physiological traits, which enable them to adapt to stressful conditions and capture resources more quickly than natives. This study further emphasizes the potential invasion of alien plants in contaminated soil environments within the introduced range. To a certain extent, some non-invasive alien plants might adapt to metalliferous environments and serve as hyperaccumulator candidates in phytoremediation projects in contaminated environments.

Patterns in functional trait variation associated with the ecological strategies of lianas and trees in subtropical montane forests remain poorly understood due to lack of trait comparisons. Here, we filled this gap by investigating trait divergence between lianas and trees with different leaf habits for 13 traits of 33 species (7 deciduous and 4 evergreen liana species, and 10 deciduous and 12 evergreen tree species) in a subtropical montane forest in southwestern China. We found that lianas had significantly larger stem xylem vessel diameter, higher theoretical hydraulic conductivity, specific leaf area, leaf nitrogen, and phosphorus concentrations, but lower leaf dry-matter content and N/P ratio than sympatric trees, indicating that lianas employ an acquisitive ecological strategy, with a more efficient stem hydraulic system and more productive leaves. In contrast to trees, lianas exhibited a larger variation in vessel diameter, with a few wide and many narrow vessels in the xylem, indicating a greater vessel dimorphism. Growth form explained 48.7% of the total trait variation, while leaf habit only explained 3.8% of trait variation, without significant interaction between growth form and leaf habit. In addition, significant stem–leaf trait relationships were only found in trees, but not in lianas, indicating decoupling of stem hydraulic function and leaf traits in subtropical lianas. These results suggest that subtropical montane lianas and trees differ strikingly in stem and leaf functional traits. Further studies are warranted to strengthen our understanding of the mechanisms underlying the strong divergence in ecological strategies between lianas and trees in subtropical forest ecosystems.

Polystichum lonchitis L. is a fern belonging to the family Dryopteridaceae. The present study was conducted to evaluate its pharmacological, antioxidant, and phytochemical properties, and to conduct GC–MS screening of P. lonchitis. The acetic acid-induced writhing test, yeast-induced hyperpyrexia method, carrageenan-induced rat paw edema model, and charcoal meal test model were carried out to assess analgesic, antipyretic, anti-inflammatory, and antispasmodic activity, respectively. DPPH was used as an antioxidant, while the phytochemical screening was conducted using standard scientific methods. Among the pharmacological activities, the most significant effects were observed in the analgesic and anti-inflammatory activities, followed by the antipyretic and antispasmodic activities, at a dose of 450 mg/kg after the 4th hour, compared with 150 mg/kg and 300 mg/kg. For the evaluation of antioxidant activities, the most significant results were detected in the methanolic and aqueous extracts. The detection of flavonoids and phenol occurred most significantly in the methanolic extract, and then in the ethanolic and aqueous extracts. The main compounds detected using GC–MS analysis with a high metabolic rate was 𝛼-D-Galactopyranoside, which had a metabolic rate of 0.851, and methyl and n-hexadecanoic, which had a metabolic rate of 0.972. Overall, the results suggested that P. lonchitis had a strong potential for pharmacological activities. The suggested assessment provided a way to isolate the bioactive constituents and will help to provide new medicines with fewer side effects. Due to the fern’s effectiveness against various diseases, the results provide clear evidence that they also have the potential to cure various diseases.