Nutrient stoichiometry and trade-offs focusing on the mass balance of multiple nutrient elements play important roles in the response mechanism of plants to environmental stresses in wetlands. Nonetheless, little is known about the response dynamics and trade-offs of nutrient elements of wetland plants, especially potassium (K), under hydrological fluctuation conditions. Greenhouse experiments have been undertaken to assess the effects of initial water level (DW), water-level amplitude (AW), lasted time and their interactions on the response processes of nutrient stoichiometry of Carex schmidtii. Plant nutrient trade-offs and limitation were investigated under multiple hydrological fluctuation conditions. Results showed that plant nitrogen (N), K and their ratio were significantly influenced by DW. Lasted time significantly affected nutrient stoichiometry except for N:P ratio. Plant N:K ratio were sensitive to the three factors and their interactions. Moreover, plant N:P and N:K ratios indicated a significant P limitation and K limitation for the growth of C. schmidtii, respectively. The scaling exponents showed that DW, AW and their interaction have significant effects on the relationships of P ~ N, K ~ N and K ~ P. Principal component analysis indicated that lasted time had significant effects on the nutrient balances. Hydrological fluctuation resulted in changes in plant nutrients and their ratios, but nutrient trade-offs relieved the negative effects. These findings help in understanding the nutrient stoichiometry and response mechanism of C. schmidtii to hydrological fluctuation and provide invaluable information for nutrient and hydrological management for tussock wetlands.

集中于多种营养元素的质量平衡的营养化学计量和取舍在植物对湿地环境胁迫的响应机制中起着重要作用。然而，在水文波动条件下，对于湿地植物尤其是钾（K）的营养元素的响应动力学和权衡取舍知之甚少。已经进行了温室实验，以评估初始水位（DW），水位振幅（AW），持续时间及其相互作用对施氏卡氏菌营养化学计量响应过程的影响。。在多种水文波动条件下研究了植物养分平衡和局限性。结果表明，DW显着影响植物的氮，钾及其比例。持续时间除了N：P比外，还显着影响营养物化学计量。植物N：K比对这三个因素及其相互作用敏感。此外，植物N：P和N：K的比例表明施密氏梭菌的显着磷限制和钾限制， 分别。标度指数表明，DW，AW及其相互作用对P〜N，K〜N和K〜P之间的关系有显着影响。主成分分析表明，持续时间对养分平衡具有显着影响。水文波动导致植物养分及其比例发生变化，但养分平衡可以减轻不利影响。这些发现有助于理解施密特氏梭菌对水文波动的养分化学计量和响应机制，并为草湿地的养分和水文管理提供了宝贵的信息。