Understanding and predicting forest mortality in the western United States using long‐term forest inventory data and modeled hydraulic damage
Understanding and predicting forest mortality in the western United States using long‐term forest inventory data and modeled hydraulic damage
复制标题
使用长期森林清查数据和模拟水力损害了解和预测美国西部的森林死亡率
DOI：
10.1111/nph.17043
复制
发表时间：
2021
期刊：
影响因子：
9.4
通讯作者：
Anderegg, William R.
中科院分区：
文献类型：
--
作者：
Venturas, Martin D.;Todd, Henry N.;Trugman, Anna T.;Anderegg, William R.
全球变暖预计将加剧美国西部干旱的持续时间和强度，这可能导致树木死亡增加。我们使用森林调查数据和一个植物水力模型(HM)来解决三个问题：我们能否用HM预测的损害阈值来捕捉干旱引起的树木死亡的区域模式；HM度量标准是否能改善广泛空间区域的死亡率预测；当考虑林分特征、气候指标和模拟水力压力时，森林死亡的主要控制因素是什么？我们发现，预测死亡的模型解释的变异量有限(R2中位数=0.10，R2范围：0.00-0.52)。与单独使用林分和气候预测因子的模型相比，包括水力破坏和碳同化诊断在内的HM输出适度改善了整个美国西部的死亡率预测。在考虑的因素中，林分密度和树木大小往往是解释死亡率的一些最关键的因素，可能突出了结构超限、林分发育、生物制剂宿主选择和暴发在死亡模式中的重要作用。
Global warming is expected to exacerbate the duration and intensity of droughts in the western United States, which may lead to increased tree mortality. A prevailing proximal mechanism of drought‐induced tree mortality is hydraulic damage, but predicting tree mortality from hydraulic theory and climate data still remains a major scientific challenge.We used forest inventory data and a plant hydraulic model (HM) to address three questions: can we capture regional patterns of drought‐induced tree mortality with HM‐predicted damage thresholds; do HM metrics improve predictions of mortality across broad spatial areas; and what are the dominant controls of forest mortality when considering stand characteristics, climate metrics, and simulated hydraulic stress?We found that the amount of variance explained by models predicting mortality was limited (R2median = 0.10,R2range: 0.00–0.52). HM outputs, including hydraulic damage and carbon assimilation diagnostics, moderately improve mortality prediction across the western US compared with models using stand and climate predictors alone.Among factors considered, metrics of stand density and tree size tended to be some of the most critical factors explaining mortality, probably highlighting the important roles of structural overshoot, stand development, and biotic agent host selection and outbreaks in mortality patterns.