Li Yage, Zhao Chunyan, Wu Jiajun, Ba Suyan, Liu Shuo, Dai Panfeng
College of Agriculture, Henan University of Science and Technology, Luoyang 471000, China.
Plants (Basel). 2025 Jul 26;14(15):2307. doi: 10.3390/plants14152307.
The environmental heterogeneity caused by altitude can lead to trade-offs in nutrient utilization and allocation strategies among plant organs; however, there is still a lack of research on the nutrient variation in the "flower-leaf-branch-fine root-soil" systems of native shrubs along altitude gradients in China's unique karst regions. Therefore, we analyzed the carbon (C), nitrogen (N), and phosphorus (P) contents and their ratios in flowers, leaves, branches, fine roots, and surface soil of shrubs across 2200-2700 m altitudinal range in southwestern China's karst areas, where this species is widely distributed and grows well. The results show that organs had higher N content than both global and Chinese plant averages. The order of C:N:P value across plant organs was branches > fine roots > flowers > leaves. Altitude significantly affected the nutrient dynamics in plant organs and soil. With increasing altitude, P content in plant organs exhibited a significant concave pattern, leading to unimodal trends in the C:P of plant organs, as well as the N:P of leaves and fine roots. Meanwhile, plant organs except branches displayed significant homeostasis coefficients in C:P and fine root P, indicating a shift in 's P utilization strategy from acquisitive-type to conservative-type. Strong positive relationships between plant organs and soil P and available P revealed that P was the key driver of nutrient cycling in shrubs, enhancing plant organ-soil coupling relationships. In conclusion, demonstrates flexible adaptability, suggesting that future vegetation restoration and conservation management projects in karst ecosystems should consider the nutrient adaptation strategies of different species, paying particular attention to P utilization.
海拔引起的环境异质性会导致植物器官间养分利用和分配策略的权衡；然而，在中国独特的喀斯特地区，沿海拔梯度的原生灌木“花-叶-枝-细根-土壤”系统中的养分变化仍缺乏研究。因此，我们分析了中国西南喀斯特地区海拔2200 - 2700米范围内灌木的花、叶、枝、细根和表层土壤中的碳（C）、氮（N）、磷（P）含量及其比率，该物种在该地区广泛分布且生长良好。结果表明，各器官的N含量高于全球和中国植物的平均水平。植物各器官的C:N:P值顺序为枝>细根>花>叶。海拔显著影响植物器官和土壤中的养分动态。随着海拔升高，植物器官中的P含量呈现显著的凹形模式，导致植物器官的C:P以及叶和细根的N:P呈现单峰趋势。同时，除枝以外的植物器官在C:P和细根P方面表现出显著的稳态系数，表明该植物的P利用策略从获取型向保守型转变。植物器官与土壤P和有效P之间的强正相关关系表明，P是该灌木养分循环的关键驱动因素，增强了植物器官与土壤的耦合关系。总之，该植物表现出灵活的适应性，这表明未来喀斯特生态系统的植被恢复和保护管理项目应考虑不同物种的养分适应策略，尤其要关注P的利用。
