Quantifying the effects of precipitation exclusion and groundwater drawdown on functional traits of Haloxylon ammodendron - How does this xeric shrub survive the drought?
Sci Total Environ
; 904: 166945, 2023 Dec 15.
Article
em En
| MEDLINE
| ID: mdl-37699482
ABSTRACT
The increasing frequency of drought and decline in groundwater levels are causing ecophysiological changes in woody plants, particularly in desert ecosystems in arid regions. However, the combined effects of meteorological and hydrological droughts on perennial desert plants, especially phreatophytes, remain poorly understood. To address this knowledge gap, we conducted a 5-year precipitation exclusion experiment at two sites with contrasting groundwater depths in the Gurbantunggut Desert located in northwest China. Our study aimed to investigate the impacts of precipitation exclusion and groundwater depth decline on multiple traits of H. ammodendron. We found that long-term precipitation exclusion enhanced midday leaf water potential, stomatal conductance, chlorophyll content, root nonstructural carbohydrates concentration, leaf starch concentration, but decreased water use efficiency. Groundwater drawdown decreased predawn and midday leaf water potentials, maximum net photosynthetic rate, stomatal conductance, Huber value, stem water δ18O, but enhanced water use efficiency and branch nonstructural carbohydrates concentration. A combination of precipitation exclusion and groundwater depth decline reduced Huber value, but did not show exacerbated effects. The findings demonstrate that hydrological drought induced by groundwater depth decline poses a greater threat to the survival of H. ammodendron than future changes in precipitation.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Água Subterrânea
/
Chenopodiaceae
Idioma:
En
Revista:
Sci Total Environ
Ano de publicação:
2023
Tipo de documento:
Article