DOI: 10.1016/j.foreco.2015.04.012
Scopus记录号: 2-s2.0-84953208080
论文题名: Conversion of natural forests to managed forest plantations decreases tree resistance to prolonged droughts
作者: Domec J.-C. ; King J.S. ; Ward E. ; Christopher Oishi A. ; Palmroth S. ; Radecki A. ; Bell D.M. ; Miao G. ; Gavazzi M. ; Johnson D.M. ; McNulty S.G. ; Sun G. ; Noormets A.
刊名: Forest Ecology and Management
ISSN: 0378-1127
出版年: 2015
卷: 355 起始页码: 58
结束页码: 71
语种: 英语
英文关键词: Cavitation
; Drought
; Natural stands
; Pine
; Roots
; Transpiration
Scopus关键词: Cavitation
; Cultivation
; Drought
; Hydraulic models
; Plants (botany)
; Soil moisture
; Soils
; Transpiration
; Cavitation resistance
; Extreme weather conditions
; Forest management practices
; Intensively managed plantations
; Loblolly pine plantations
; Pine
; Roots
; Vapor pressure deficit
; Forestry
; Pinus taeda
英文摘要: Throughout the southern US, past forest management practices have replaced large areas of native forests with loblolly pine plantations and have resulted in changes in forest response to extreme weather conditions. However, uncertainty remains about the response of planted versus natural species to drought across the geographical range of these forests. Taking advantage of a cluster of unmanaged stands (85-130year-old hardwoods) and managed plantations (17-20year-old loblolly pine) in coastal and Piedmont areas of North Carolina, tree water use, cavitation resistance, whole-tree hydraulic (Ktree) and stomatal (Gs) conductances were measured in four sites covering representative forests growing in the region. We also used a hydraulic model to predict the resilience of those sites to extreme soil drying. Our objectives were to determine: (1) if Ktree and stomatal regulation in response to atmospheric and soil droughts differ between species and sites; (2) how ecosystem type, through tree water use, resistance to cavitation and rooting profiles, affects the water uptake limit that can be reached under drought; and (3) the influence of stand species composition on critical transpiration that sets a functional water uptake limit under drought conditions. The results show that across sites, water stress affected the coordination between Ktree and Gs. As soil water content dropped below 20% relative extractable water, Ktree declined faster and thus explained the decrease in Gs and in its sensitivity to vapor pressure deficit. Compared to branches, the capability of roots to resist high xylem tension has a great impact on tree-level water use and ultimately had important implications for pine plantations resistance to future summer droughts. Model simulations revealed that the decline in Ktree due to xylem cavitation aggravated the effects of soil drying on tree transpiration. The critical transpiration rate (Ecrit), which corresponds to the maximum rate at which transpiration begins to level off to prevent irreversible hydraulic failure, was higher in managed forest plantations than in their unmanaged counterparts. However, even with this higher Ecrit, the pine plantations operated very close to their critical leaf water potentials (i.e. to their permissible water potentials without total hydraulic failure), suggesting that intensively managed plantations are more drought-sensitive and can withstand less severe drought than natural forests. © 2015 Published by Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/65660
Appears in Collections: 影响、适应和脆弱性
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作者单位: Bordeaux Sciences AGRO, UMR 1391 ISPA INRA, 1 Cours du général de Gaulle 33175, Gradignan Cedex, France; Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, NC, United States; Southern Research Station USDA Forest Service, Coweeta, NC, United States; Nicholas School of the Environment and Earth Sciences, Duke University, Durham, NC, United States; Pacific Northwest Research Station, USDA Forest Service, Corvallis, OR, United States; Eastern Forest Environmental Threat Assessment Center, USDA Forest Service, Raleigh, NC, United States; Department of Forest, Rangeland and Fire Sciences, University of Idaho, Moscow, ID, United States
Recommended Citation:
Domec J.-C.,King J.S.,Ward E.,et al. Conversion of natural forests to managed forest plantations decreases tree resistance to prolonged droughts[J]. Forest Ecology and Management,2015-01-01,355