Plant nutrient responses

植物组织养分浓度和比例是生态系统过程和生态相互作用的重要预测因子。该项目的总体目标是研究植物多样性对植物营养反应的时间动态的影响，包括其作为时间长期不变性的稳定性、环境扰动期间的抗性和环境扰动后的恢复。（1）分析主试验植物地上生物量中碳（C）、氮（N）、磷（P）和钾（K）元素浓度、比例和储量的时间序列数据。我们的目标是确定的驱动程序的多样性影响植物群落养分响应及其时间变异性，结合植物群落组成，土壤特性和环境变化的变化数据。(2)我们将收集主要实验植物群落中所有播种物种的叶片材料，以研究C、N、P和K的特定浓度。利用这些数据，我们打算分解的重要性，植物群落组成与种内变异的重要性，叶营养浓度的社区手段和多样性的植物组织元素浓度在长期的生物多样性实验，这不能单独解开与社区水平的数据。(3)我们将研究物种特异性吸收同位素示踪剂（15 N，13 C）和碳和氮浓度在植物地上生物量在干旱和再湿润阶段的ResCUE实验，以评估如何植物和功能性状多样性缓冲对社区水平的C和N吸收的下降在干旱和促进增加社区水平的C和N吸收时，植物群落恢复在再湿润。我们将分析如何分配到不同的功能组，并区分不同的功能性状相关的抗旱性植物物种在干旱和复湿阶段的C和N吸收的变化。在社区一级，我们还将在ResCUE实验的两个阶段测量地上植物材料中的P和K浓度，以直接评估气候事件如何影响植物多样性对社区一级浓度的影响，不同营养素的比例和池。

Plant tissue nutrient concentrations and ratios are important predictors of ecosystem processes and ecological interactions. The overall objective of this project is to study the effects of plant diversity on the temporal dynamics of plant nutrient responses, including their stability as temporal long-term invariability, resistance during and recovery after environmental perturbations. The project is organized in three work packages: (1) We will analyze the time-series data of community-level elemental concentrations, ratios and stocks of carbon (C), nitrogen (N), phosphorus (P) and potassium (K) in plant aboveground biomass of the Main Experiment. We aim to identify the drivers underlying diversity effects on plant community nutrient responses and their temporal variability by incorporating data on changes in plant community composition, soil characteristics and environmental changes. (2) We will collect leaf material of all sown species in the plant communities of the Main Experiment to study specific-specific concentrations of C, N, P and K. Using these data, we intend to decompose the importance of plant community composition versus the importance of intraspecific variation in leaf nutrient concentrations for the community means and diversity of plant tissue elemental concentrations in the long-term biodiversity experiment, which cannot be disentangled alone with community-level data. (3) We will study the species-specific uptake of isotopic tracers (15N, 13C) and carbon and nitrogen concentrations in plant aboveground biomass during the drought and re-wetting phase of the ResCUE Experiment to assess how plant and functional trait diversity buffer against the decline in community-level C and N uptake during drought and promote increased community-level C and N uptake when plant communities recover during re-wetting. We will analyze how plant species assigned to different functional groups and distinguished by different functional traits related to drought resistance vary in their C and N uptake during the drought and re-wetting phase. At the community level, we will also measure concentrations of P and K in aboveground plant material in both phases of the ResCUE Experiment to directly evaluate how climate events influence plant diversity effects on community-level concentrations, ratios and pools of different nutrients.