在常青森林中量化PSII开放中心和多尺度光合作用电子传输与太阳能诱导的叶绿素光
Weiwei Cong1, Xiao Li1, Kaijie Yang2,3,4,5,6
1College of Agronomy, Shenyang Agricultural University, Shenyang, China.
Physiologia plantarum
|December 17, 2025
概括
一个新的SIF-qL氧化还原模型使用太阳诱导的光精确估计了光合作用变量,如开放的光系统II反应中心 (qL) 和电子传输速率 (JPSII). 该模型显示了从叶子到树冠的跨度适用性,有助于生态系统光合作用研究.
科学领域:
- 植物生理学和光合作用
- 生态系统生态学生态学
- 植被的远程传感 植被的远程传感
背景情况:
- 精确量化光合作用变量,如光系统II (PSII) 开放反应中心 (qL) 和电子传输速率 (ETR),对于理解生态系统动态至关重要.
- 由于观测的局限性和复杂的环境反,估计这些变量是具有挑战性的,特别是在动态条件下.
- 将叶层级的流程与树冠尺度的理解联系起来,需要强大的模型,可以在空间尺度上进行验证.
研究的目的:
- 开发和验证一种新的SIF-qL氧化还原模型,以使用太阳诱导的叶绿素光 (SIF) 来机械量化qL和线性电子传输速率 (JPSII).
- 评估模型的准确性和跨度适用性 (叶子到树冠) 在常青森林生态系统中.
- 研究JPSII和qL之间的关系,并确定电子传输的限制因素.
主要方法:
- 建立了SIF-qL氧化还原模型来从SIF测量中量化qL和JPSII.
- 在两个常青森林地点 (ZGT和DEJU) 验证了该模型,使用连续脉冲振幅调制 (PAM) 叶绿素光和流量测量.
- 在叶子和树冠尺度上评估模型性能,分析不同的qL动态和JPSII-qL关系.
主要成果:
- SIF-qL还氧化模型在预测ZGT位点的叶子水平qL时显示出高准确度 (R2 = 0.82),但在DEJU (R2 = 0.45) 时的准确度较低.
- 在两个地点都准确地模拟了叶片级 JPSII 动态 (R2 = 0.92-0.97),在树冠尺度 (R2 = 0.62-0.71) 中保持了可靠的预测能力.
- 对光合作用活性辐射 (PAR) 和温度观察到明显的qL反应,Ribulose-1,5-bisphosphate (RUBP) 生成限制被确定为JPSII的主导.
结论:
- SIF-qL还氧化模型提供了SIF和光合作用动力学之间的机械联系,证明了跨规模模拟的潜力.
- 该研究强调了考虑特定物种和环境因素的重要性,以提高该模型在生态系统光合作用研究中的普遍适用性.
- 需要进行改进,以提高模型在各种植被类型和环境条件中的性能.
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