植物生态学报 ›› 2018, Vol. 42 ›› Issue (9): 885-905.DOI: 10.17521/cjpe.2018.0083

• 综述 •    下一篇

树木吸收利用深层土壤水的特征与机制: 对人工林培育的启示

席本野1,*(),邸楠1,*,曹治国1,4,*,刘金强1,李豆豆1,王烨1,2,李广德3,段劼1,贾黎明1,张瑞娜1   

  1. 1北京林业大学省部共建森林培育与保护教育部重点实验室, 北京 100083
    2北京市农林科学院林业果树研究所, 北京 100093
    3国家开放大学农林医学教育部, 北京 100039
    4河南师范大学环境学院, 黄淮水环境污染防治省部共建教育部重点实验室, 河南新乡 453007
  • 收稿日期:2018-04-11 修回日期:2018-09-10 出版日期:2018-09-20 发布日期:2018-09-26
  • 通讯作者: 席本野,邸楠,曹治国
  • 基金资助:
    国家自然科学基金(31872702);国家自然科学基金(31670625);国家自然科学基金(31400532);国家重点研发计划课题(2016YFD0600403);“十二五”国家科技支撑计划(2015BAD09B02)

Characteristics and underlying mechanisms of plant deep soil water uptake and utilization: Implication for the cultivation of plantation trees

XI Ben-Ye1,*(),DI Nan1,*,CAO Zhi-Guo1,4,*,LIU Jin-Qiang1,LI Dou-Dou1,WANG Ye1,2,LI Guang-De3,DUAN Jie1,JIA Li-Ming1,ZHANG Rui-Na1   

  1. 1Ministry of Education Key Laboratory of Silviculture and Conservation, Beijing Forestry University, Beijing 100083, China
    2Institute of Agriculture and Forestry Sciences, Beijing Academy of Forestry and Pomology, Beijing 100093, China
    3Faculty of Agriculture, Forestry and Medicine, The Open University of China, Beijing 100039, China
    4 Key Laboratory for Yellow River and Huaihe River Water Environmental and Pollution Control, Ministry of Education, School of Environment, Henan Normal University, Xinxiang, Henan 453007, China
  • Received:2018-04-11 Revised:2018-09-10 Online:2018-09-20 Published:2018-09-26
  • Contact: Ben-Ye XI,Nan DI,Zhi-Guo CAO
  • Supported by:
    Supported by the National Natural Science Foundation of China(31872702);Supported by the National Natural Science Foundation of China(31670625);Supported by the National Natural Science Foundation of China(31400532);the National Key Research and Development Program of China(2016YFD0600403);the Key Technologies R&D Program of China(2015BAD09B02)

摘要:

根系吸水是树木水分关系的重要环节, 在树木生理活动中发挥着至关重要的作用。深层土壤中的水资源含量一般相对较高, 常可为树木生长供给大量水分, 并在旱季保障其生存与正常生长。因此, 了解树木对深层土壤水的吸收利用特征与机制, 可帮助深入认识树木与环境的互作机制、树木的生长与生存策略、物种间的共存与竞争机制等内容, 同时还可帮助构建既能降低外部水资源投入, 又能避免水分生态环境负面效应的人工林绿色栽培制度。基于已有研究, 该文对树木吸收利用深层土壤水的特征与机制进行了综述。首先, 探讨了深层根系和深层土壤的界定, 指出对于除寒温带针叶林以外的其他主要森林植被类型, 可以1 m作为树木深根系和深土层的平均划分(参考)标准, 并明确了全球范围内树木深根系的成因。其次, 对已有研究中观察到的树木对深层土壤水的吸收利用特征及其影响因素进行了归纳与总结, 并从深根系性状调节、整株水力特性协调两方面探讨了树木高效吸收利用深层土壤水的机制, 如可通过深根系的空间、时间和效率调节策略来促进对深土层水分的吸收。最后, 提出了树木利用深土层水分对人工林培育的几点启示, 包括水分管理.中应使林木适度利用深层土壤水, 选用合适的灌水频率、合理的树种混交能促进深层土壤水分储库“缓冲”作用的发挥, 基于树木土壤水分利用深度的间伐木选择技术等, 并指出了该领域现有研究的不足以及今后的发展方向。

关键词: 深根系, 深土层, 根系吸水, 水力提升, 细根, 人工林

Abstract:

Root water uptake is an essential part of tree water relations and plays a crucial role in tree physiological activities. Water resource in deep soil is relatively abundant and can provide plenty of water to trees to guarantee their survival and healthy growth during dry seasons. Thus, a good comprehension of the characteristics and underlying mechanisms of deep soil water uptake and utilization by trees will deepen the understanding of the interaction between trees and the environment, tree survival and growth strategies, coexistence and competition among different species, etc. This knowledge is important in establishing green cultivation schemes for plantations, which depend less on the external water resources input and avoid the adverse effects on the water ecological environment. From existing studies, the characteristics and underlying mechanisms of deep water uptake and utilization by trees are reviewed. Firstly, the definition of deep roots and deep soil is discussed, and 1 m depth is recommended as the average (reference) definition standard in main forest vegetation types except the boreal forest. The reasons for the formation of deep tree roots around the globe were also determined. Secondly, the observed deep soil water uptake characteristics of trees and their influencing factors are summarized. Then, from the aspects of the adjustment of deep root traits and the coordination of hydraulic traits of different organs, the mechanisms of deep water uptake by trees are discussed. For example, the spatial, temporal and efficiency adjustment strategies of deep roots can be used to facilitate the absorption of deep soil water. Finally, some implications of deep soil water uptake for the cultivation of plantations are proposed, such as “for water management in plantations, trees should be induced to moderately utilize some deep soil water and an appropriate irrigation frequency should be selected”, “appropriate mixed planting of different tree species can facilitate the buffering effect of deep soil water storage”, “developing techniques of selecting trees for thinning based on the water uptake depths of different species”, etc. Deficiencies of existing studies and some future research directions were also pointed out.

Key words: deep root, deep soil, root water uptake, hydraulic lift, fine root, plantation