气候变化领域集成服务门户(CCPortal): Microtopographic refugia against drought in temperate forests: Lower water availability but more extensive fine root system in mounds than in pits

CCPortal

DOI	10.1016/j.foreco.2020.118439
	Microtopographic refugia against drought in temperate forests: Lower water availability but more extensive fine root system in mounds than in pits
	Tauc F.; Houle D.; Dupuch A.; Doyon F.; Maheu A.
发表日期	2020
ISSN	0378-1127
卷号	476
英文摘要	Water stress is one of the primary drivers of forest mortality and, with climate change, an increase in drought duration and severity is expected. Microtopography may offer hydrologic refugia against exposure to drought but how these local conditions affect fine root development of trees, and thus their sensitivity to drought, remains, however, poorly known. We studied how microtopography and water limitations influence the fine root system of two tree species, sugar maple (Acer saccharum) and bitternut hickory (Carya cordiformis), in natural forest stands at 16 sites in the temperate forest of southern Quebec (Canada). At each site, we measured the fine root standing crop and production (length, mass, and specific root length (SRL)) of four mature trees per species, located in pits and mounds. Half of them were also exposed to a rainfall exclusion for three months. We measured soil water potential at the base of each tree throughout the growing season. Soil water availability was significantly lower in mounds (mean ± SE: −22.5 ± 0.9 kPa) than in pits (−16.0 ± 1.0 kPa). We found a more extensive fine root system for trees in mounds than in pits, both in terms of length and mass; the standing crop length was 19% greater and the production length at a 20–40 cm depth was 77% greater in mounds than in pits. Fine root standing crop was slightly reduced in the rainfall exclusion treatment, whatever the microtopographical position. The sugar maple had a greater standing crop mass (but not length), and a greater fine root production at deeper soil layers (20–40 cm) than the bitternut hickory. Still, microtopography had a greater influence than tree species on fine root production at the deepest soil layer (30–40 cm). Overall, this study is a first step towards a better understanding of the interaction between micro-environmental conditions and rooting strategies. Our findings highlight the distinct acclimation to microtopography of the fine root system of trees, which could play a crucial role regarding their response to drought. © 2020 Elsevier B.V.
英文关键词	Fine root daily production; Fine root standing crop; Microrefuge; Microtopography; Rainfall exclusion; Temperate forest
语种	英语
scopus关键词	Climate change; Crops; Drought; Plants (botany); Rain; Soil moisture; Sugar industry; Environmental conditions; Fine root systems; Natural forest stands; Soil water availability; Soil water potential; Specific root length; Temperate forests; Water availability; Forestry; acclimation; deciduous forest; drought stress; fine root; growing season; microtopography; refugium; soil water potential; stand dynamics; temperate forest; water availability; water stress; Drought; Farm Crops; Forestry; Pits; Production; Rain; Trees; Canada; Quebec [Canada]; Acer saccharum; Carya cordiformis
来源期刊	Forest Ecology and Management
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/155012
作者单位	Institut des sciences de la forêt tempérée, Université du Québec en Outaouais, Ripon, QC, Canada; Ministère des Forêts, de la Faune et des Parcs, Québec, QC, Canada; Ouranos, Montréal, QC, Canada
推荐引用方式 GB/T 7714	Tauc F.,Houle D.,Dupuch A.,et al. Microtopographic refugia against drought in temperate forests: Lower water availability but more extensive fine root system in mounds than in pits[J],2020,476.
APA	Tauc F.,Houle D.,Dupuch A.,Doyon F.,&Maheu A..(2020).Microtopographic refugia against drought in temperate forests: Lower water availability but more extensive fine root system in mounds than in pits.Forest Ecology and Management,476.
MLA	Tauc F.,et al."Microtopographic refugia against drought in temperate forests: Lower water availability but more extensive fine root system in mounds than in pits".Forest Ecology and Management 476(2020).