Effects of size and microclimate on whole-tree water use and hydraulic regulation in Schima superba trees

PeerJ

article

Xiao-wei Zhao¹  Lei Ouyang²  Ping Zhao²  Chun-fang Zhang³ 

[1] College of Life Sciences, Yulin University;Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences;Department of Life Sciences, Yuncheng College

关键词: Sap flux density;    Transpiration;    Leaf water potential;    Hydraulic conductance;    Canopy conductance;   

DOI  :  10.7717/peerj.5164

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

BackgroundPlant-water relations have been of significant concern in forestry and ecology studies in recent years, yet studies investigating the annual differences in the characteristics of inter-class water consumption in trees are scarce.MethodsWe classified 15 trees from a Schima superba plantation in subtropical South China into four ranks using diameter at breast height (DBH). The inter-class and whole-tree water use were compared based on three parameters: sap flux density, whole-tree transpiration and canopy transpiration over two years. Inter-class hydraulic parameters, such as leaf water potential, stomatal conductance, hydraulic conductance, and canopy conductance were also compared.Results(1) Mean water consumption of the plantation was 287.6 mm over a year, 165.9 mm in the wet season, and 121.7 mm in the dry season. Annual mean daily water use was 0.79 mm d−1, with a maximum of 1.39 mm d−1. (2) Isohydrodynamic behavior were found in S. superba. (3) Transpiration was regulated via both hydraulic conductance and stoma; however, there was an annual difference in which predominantly regulated transpiration.DiscussionThis study quantified annual and seasonal water use of a S. superba plantation and revealed the coordinated effect of stoma and hydraulic conductance on transpiration. These results provide information for large-scale afforestation and future water management.

【 授权许可】

CC BY