干旱区生态环境知识资源中心(Arid): Water availability influences thermal safety margins for leaves

Arid

DOI	10.1111/1365-2435.13868
	Water availability influences thermal safety margins for leaves
	Cook, Alicia M.; Berry, Neil; Milner, Kirsty V.; Leigh, Andrea
通讯作者	Cook, AM (corresponding author), Univ Technol Sydney, Sch Life Sci, Broadway, NSW, Australia.
来源期刊	FUNCTIONAL ECOLOGY
ISSN	0269-8463
EISSN	1365-2435
出版年	2021
英文摘要	1. One application of plant physiological heat tolerance measurements is the assessment of vulnerability to increasing environmental temperatures under climatic change. A thermal safety margin (TSM), the difference between physiological tolerance and environmental temperature, is a common metric for the assessment of plant thermal vulnerability. However, there are biological and methodological aspects to consider when evaluating thermal vulnerability that have the potential to substantially alter the assessments. Two such aspects include the leaf to air temperature relationship and the scale at which air temperature data are collected. 2. We grew plants of a desert species, Myoporum montanum, in situ under water-stressed and well-watered conditions, and measured their leaf temperatures and photosynthetic heat tolerance (T-50 threshold) every third day over 12 days in summer. Thermal safety margins were calculated based on leaf temperatures and compared to those calculated with local and regional air temperatures. 3. We found that heat tolerance and the thermal vulnerability assessment of a plant changed with water status. When water was readily available, plants maintained wide leaf temperature safety margins and displayed partial homeothermy. When cooling via transpiration was limited, increasing leaf temperature corresponded with occurrences of leaf poikilo-and megathermy, higher heat tolerance and narrower safety margins. 4. Our study shows high physiological heat thresholds are not necessarily reflective of wide safety margins, but instead can indicate a greater vulnerability and increased risk of heat stress exposure. Calculating TSMs using air temperatures can also substantially alter margin widths. Where possible, the use of leaf temperatures in assessments of thermal vulnerability will lead to more meaningful vulnerability assessments. We recommend considering the source and temporal pairing of temperature measurements as well as plant water status, when measuring and interpreting plant TSMs.
英文关键词	climate model predictions heat tolerance photosynthetic thermal tolerance thermal safety margin thermal tolerance thermal vulnerability thermotolerance
类型	Article ; Early Access
语种	英语
开放获取类型	Green Accepted
收录类别	SCI-E
WOS记录号	WOS:000670800100001
WOS关键词	HIGH-TEMPERATURE ; CHLOROPHYLL FLUORESCENCE ; LEAF TEMPERATURE ; PHOTOSYSTEM-II ; HEAT TOLERANCE ; CLIMATE-CHANGE ; GAS-EXCHANGE ; DESERT ; PHOTOSYNTHESIS ; STRESS
WOS类目	Ecology
WOS研究方向	Environmental Sciences & Ecology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/352193
作者单位	[Cook, Alicia M.; Berry, Neil; Milner, Kirsty V.; Leigh, Andrea] Univ Technol Sydney, Sch Life Sci, Broadway, NSW, Australia
推荐引用方式 GB/T 7714	Cook, Alicia M.,Berry, Neil,Milner, Kirsty V.,et al. Water availability influences thermal safety margins for leaves[J],2021.
APA	Cook, Alicia M.,Berry, Neil,Milner, Kirsty V.,&Leigh, Andrea.(2021).Water availability influences thermal safety margins for leaves.FUNCTIONAL ECOLOGY.
MLA	Cook, Alicia M.,et al."Water availability influences thermal safety margins for leaves".FUNCTIONAL ECOLOGY (2021).