Understanding and predicting forest mortality in the western United States using long-term forest inventory data and modeled hydraulic damage.
New Phytol
; 230(5): 1896-1910, 2021 06.
Article
em En
| MEDLINE
| ID: mdl-33112415
ABSTRACT
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 (R2 median = 0.10, R2 range 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.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Florestas
/
Secas
Tipo de estudo:
Prognostic_studies
/
Risk_factors_studies
País/Região como assunto:
America do norte
Idioma:
En
Revista:
New Phytol
Assunto da revista:
BOTANICA
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Estados Unidos