关于植物液压和光合作用温度适应的不同模型假设在变暖下对热带森林总初级产量产生不同的影响
Claire M Zarakas1, Abigail L S Swann1,2, Charles D Koven3
1Department of Atmospheric Sciences, University of Washington, Seattle, Washington, USA.
Global change biology
|September 20, 2024
概括
热带森林的光合作用因生化和口腔反应而随着热量下降. 模型显示,直接的温度效应导致比蒸汽压力缺陷 (VPD) 效应更大的下降,影响未来的初级生产总值 (GPP) 弹性.
科学领域:
- 生态生态学 生态生态学
- 气候变化生物学 气候变化生物学
- 森林科学 森林科学 森林科学
背景情况:
- 热带森林的光合作用对温度上升很敏感,受到生化和口腔反应的影响.
- 区分温度和蒸汽压力缺陷 (VPD) 对光合作用的影响是具有挑战性的,因为它们在热带生态系统中的相关性.
- 了解这些机制对于预测气候变化下的热带森林总初级产量 (GPP) 至关重要.
研究的目的:
- 使用陆地生物圈模型量化温度和VPD对热带森林光合作用的相对影响.
- 评估不同的生理假设和植物特征如何影响气候变暖对GPP的预期影响.
- 评估GPP预测对强调直接温度与VPD效应的模型配置的敏感性.
主要方法:
- 利用两种陆地生物圈模型在三个热带森林地点模拟光和GPP.
- 纳入了关于光合作用温度适应和植物液压压力的不同假设,包括最大的树脂导电性.
- 模拟理想化的气候变化场景,以在不同的模型参数化下比较GPP反应.
主要成果:
- 强调直接温度效应的模型配置预测了在变暖下更大的GPP下降.
- 支持更强的VPD效应的假设表明GPP对变暖的抵抗力更大.
- 温度与VPD对GPP的相对影响对植物功能特征和模型结构假设非常敏感.
结论:
- 准确量化直接温度和间接VPD影响对于预测热带森林对气候变化的适应性至关重要.
- 关于光合作用温度适应和植物液压的模型参数化显著影响GPP预测.
- 未来的研究应该专注于改进这些参数,以改善对热带森林的气候变化影响评估.
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