Leaf Multi-Element Network Reveals the Change of Species Dominance Under Nitrogen Deposition

Divergent responses of plant multi-element coupling to nitrogen and phosphorus addition in a meadow steppe

The intricate biogeochemical cycling of multiple elements plays a pivotal role in upholding a myriad of ecosystem functions. However, our understanding of elemental stoichiometry and coupling in response to global changes remains primarily limited to plant carbon: nitrogen: phosphorus (C: N: P). Here, we assessed the responses of 11 elements in plants from different functional groups to global changes. Investigating the stoichiometric ratios and interrelationships of these elements in response to global change is crucial for advancing our understanding of nutrient cycling dynamics in ecosystems. We found that N deposition induced stoichiometric imbalances in Gramineae, leading to a reduction in elemental coupling. This disruption in elemental coupling could potentially affect plant growth and ecosystem functioning. However, leguminous plants, which possess specialized nitrogen fixation mechanisms, were unaffected, suggesting that their ability to independently regulate N may help them maintain stable nutrient ratios despite external N inputs. These findings highlight functional differences among plant groups in their response to global changes, with important implications for ecosystem resilience and nutrient dynamics. In summary, these diverse responses underscore the importance of understanding the underlying mechanisms to be able to better predict the future trajectory of terrestrial biogeochemical cycles under global N enrichment.

Adaptability of Wild-Growing Tulips of Greece: Uncovering Relationships between Soil Properties, Rhizosphere Fungal Morphotypes and Nutrient Content Profiles

Wild-growing Greek tulips are protected plants but almost nothing is known about their natural nutrient status and rhizosphere fungal morphotypes in the wild, thus no insight is currently available into their growth and adaptation to their natural environment or artificial settings. To this end, several botanical expeditions were conducted with a special collection permit, and 34 tulip and soil samples were collected, representing 13 species from two phytogeographical regions of Greece (North Aegean Islands, Crete Island) and seven regions of mainland Greece. The tulips' content in essential macro- and micro-nutrients, respective physicochemical soil properties, and rhizosphere fungal morphotypes were assessed across samples, and all parameters were subjected to appropriate statistical analysis to determine their interrelationships. The results showed that soil variables played a significant role in shaping tulips' nutrient content, explaining up to 67% of the detected variability as in the case of phosphorus (P) in the above-ground plant tissue. In addition, significant correlations were observed (with an r value of up to 0.65, p < 0.001) between essential nutrients in the tulips, such as calcium (Ca) and boron (B). The principal component analysis (PCA) revealed that between the three spatial units examined, the total variability of tulips' nutrient content produced a clear distinction among sampled species, while the first two PCA axes managed to explain 44.3% of it. This was further confirmed by the analysis of variance (ANOVA) results which showed corresponding significant differences (at p < 0.05) in both the tulips' nutrient content and the studied soil properties as well (mean values of N, P, and K in the North Aegean Islands tulips' nutrient content, up to 53%, 119%, and 54% higher compared to those of the Crete Island, respectively). Our study sheds light on Greek tulips' adaptability and resilience in their original habitats, facilitating at the same time the undertaken efforts regarding their conservation and potential domestication in artificial settings.