干旱区生态环境知识资源中心(Arid): Heat Waves Alter Carbon Allocation and Increase Mortality of Aleppo Pine Under Dry Conditions

Arid

DOI	10.3389/ffgc.2018.00008
	Heat Waves Alter Carbon Allocation and Increase Mortality of Aleppo Pine Under Dry Conditions
	Birami, Benjamin; Gattmann, Marielle; Heyer, Arnd G.; Grote, Rudiger; Arneth, Almut; Ruehr, Nadine K.
通讯作者	Birami, B ; Ruehr, NK
来源期刊	FRONTIERS IN FORESTS AND GLOBAL CHANGE
EISSN	2624-893X
出版年	2018
卷号	1
英文摘要	Climate extremes are likely to occur more frequently in the future, including a combination of heat waves and drought. However, the responses of trees to combined stress and their post-stress recovery are not fully understood yet. Therefore, this study investigated the responses of semi-arid Pinus halepensis seedlings to moderate drought, heat and combined heat-drought stress, as well as post-stress recovery. The seedlings were grown under controlled conditions and exposed to two 4-days-long heat periods, reaching air temperature maxima of 42 degrees C and vapor pressure deficit (VPD) of 7 kPa. Day- and nighttime canopy gas exchange was measured and differences in shoot and root allocation of non-structural carbohydrate (NSC) compounds (soluble sugars, starch, cyclitols, and carboxylic acids) assessed. Fluorescence parameters, nitrate levels, proline content and shoot water potential (psi) provided additional indicators for stress severity and recovery performance. During the heat periods, net photosynthesis and stomatal conductance decreased immediately. This decline was modest under well-watered conditions, with transpiration and dark respiration rates remaining high and despite reductions in root NSC content, trees recovered following heat release. This was not the case in the heat-drought treatment, where stress resulted in high mortality rates and the few surviving seedlings showed reduced gas exchange rates and low root NSC content, while leaf nitrate and proline remained elevated even 3 weeks after heat release. Shoot psi indicated that hydraulic failure was not the reason for mortality in the heat-drought seedlings. Instead, we argue that low transpiration rates, which resulted in needle temperatures >47 degrees C during heat stress (6 degrees C above air temperature) have caused irreversible damage. In summary, it could be demonstrated that heat waves in combination with moderate drought can either result in increased mortality or, if the seedlings survive, in delayed recovery. This highlights the potential of an increase in heat wave temperatures to trigger forest decline in semi-arid regions.
英文关键词	carbon allocation combined stress cyclitols extreme heat wave nitrate non-structural carbohydrates proline recovery
类型	Article
语种	英语
开放获取类型	DOAJ Gold, Green Published
收录类别	ESCI
WOS记录号	WOS:000504089800001
WOS关键词	NITRATE REDUCTASE-ACTIVITY ; LIGHT-HARVESTING COMPLEX ; RECENTLY FIXED CARBON ; WATER-USE EFFICIENCY ; STOMATAL CONDUCTANCE ; HIGH-TEMPERATURE ; CLIMATE-CHANGE ; THERMAL-ACCLIMATION ; SEMIARID FORESTS ; ROOT RESPIRATION
WOS类目	Ecology ; Forestry
WOS研究方向	Environmental Sciences & Ecology ; Forestry
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/333371
作者单位	[Birami, Benjamin; Gattmann, Marielle; Grote, Rudiger; Arneth, Almut; Ruehr, Nadine K.] Karlsruhe Inst Technol, Inst Meteorol & Climate Res Atmospher Environm Re, Karlsruhe, Germany; [Heyer, Arnd G.] Univ Stuttgart, Inst Biomat & Biomol Syst Plant Biotechnol, Stuttgart, Germany
推荐引用方式 GB/T 7714	Birami, Benjamin,Gattmann, Marielle,Heyer, Arnd G.,et al. Heat Waves Alter Carbon Allocation and Increase Mortality of Aleppo Pine Under Dry Conditions[J],2018,1.
APA	Birami, Benjamin,Gattmann, Marielle,Heyer, Arnd G.,Grote, Rudiger,Arneth, Almut,&Ruehr, Nadine K..(2018).Heat Waves Alter Carbon Allocation and Increase Mortality of Aleppo Pine Under Dry Conditions.FRONTIERS IN FORESTS AND GLOBAL CHANGE,1.
MLA	Birami, Benjamin,et al."Heat Waves Alter Carbon Allocation and Increase Mortality of Aleppo Pine Under Dry Conditions".FRONTIERS IN FORESTS AND GLOBAL CHANGE 1(2018).