干旱区生态环境知识资源中心(Arid): A Regional Assessment of Changes in Plant-Plant Interactions Along Topography Gradients in Tunisian Sebkhas

Arid

DOI	10.1007/s10021-020-00567-8
	A Regional Assessment of Changes in Plant-Plant Interactions Along Topography Gradients in Tunisian Sebkhas
	Chaieb, Ghassen; Abdelly, Chedly; Michalet, Richard
通讯作者	Michalet, R
来源期刊	ECOSYSTEMS
ISSN	1432-9840
EISSN	1435-0629
英文摘要	Facilitation among plants in dry ecosystems is crucial for diversity and ecosystem functioning and stability. However, the importance of facilitation in extremely stressful conditions is highly debated. We attempt to separate the effects of direct non-resource and resource stress factors on plant-plant interactions by assessing changes in facilitation and competition along salinity gradients at two contrasting levels of aridity. We selected eight saline depressions (hereafter sebkhas) in the wet and dry Mediterranean arid climate of North Africa, from central Tunisia to the Libyan border 500 km south-eastward. In each sebkha, we transplanted at four positions along the salinity gradient induced by topography, both in open areas and below dominant shrubs, three target species with contrasting tolerances to salinity stress. Target plant survival, soil electrical conductivity and moisture were recorded before and after the dry summer season in all treatments. Shrubs decreased salinity and drought stresses in all treatments, and facilitation was the dominant interaction. However, we found a strong collapse of facilitation along the salinity gradient, due to a dramatic mortality of the three target species both with and without neighbours above their threshold of salinity tolerance. Increasing aridity induced an earlier collapse of facilitation along the gradient. The three target species had contrasting responses to neighbours, with the least stress-tolerant species being facilitated and the two most stress-tolerant ones negatively affected by neighbours. Our study shows that disentangling resource and non-resource stresses along gradients and controlling for target species effects help understanding variation in plant-plant interactions under highly stressful conditions.
英文关键词	Collapse of facilitation competition drought Mediterranean climate non-resource factors resource factors salinity
类型	Article ; Early Access
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000575715600001
WOS关键词	POSITIVE SPECIES INTERACTIONS ; BIOTIC INTERACTIONS ; STRESS TOLERANCE ; ABIOTIC STRESS ; FACILITATION ; HYPOTHESIS ; SHRUB ; ENVIRONMENTS ; COMPETITION ; COMMUNITY
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/2XILL650/328327
作者单位	[Chaieb, Ghassen] Univ Carthage, Fac Sci Bizerte, Zarzouna 7021, Tunisia; [Chaieb, Ghassen; Michalet, Richard] Univ Bordeaux, UMR CNRS EPOC 5805, Allee Geoffroy St Hilaire CS 50023, F-33615 Pessac, France; [Chaieb, Ghassen; Abdelly, Chedly] Ctr Biotechnol Borj Cedria, Lab Extremophiles Plants, Hammam Lif 2050, Tunisia
推荐引用方式 GB/T 7714	Chaieb, Ghassen,Abdelly, Chedly,Michalet, Richard. A Regional Assessment of Changes in Plant-Plant Interactions Along Topography Gradients in Tunisian Sebkhas[J].
APA	Chaieb, Ghassen,Abdelly, Chedly,&Michalet, Richard.
MLA	Chaieb, Ghassen,et al."A Regional Assessment of Changes in Plant-Plant Interactions Along Topography Gradients in Tunisian Sebkhas".ECOSYSTEMS