干旱区研究 ›› 2022, Vol. 39 ›› Issue (2): 551-559.doi: 10.13866/j.azr.2022.02.22

• 植物与植物生理 • 上一篇    下一篇

疏叶骆驼刺叶、根生态化学计量特征对水氮添加的响应

余洋1,2,3,4(),张志浩1,2,3,杨建明5,柴旭田1,2,3,4,曾凡江1,2,3()   

  1. 1.中国科学院新疆生态与地理研究所,新疆荒漠植物根系生态与植被修复重点实验室,新疆 乌鲁木齐 830011
    2.中国科学院新疆生态与地理研究所,荒漠与绿洲生态国家重点实验室,新疆 乌鲁木齐 830011
    3.新疆策勒荒漠草地生态系统国家野外科学观测研究站,新疆 策勒 848300
    4.中国科学院大学,北京 100049
    5.新疆维吾尔自治区林业和草原局生态保护修复处,新疆 乌鲁木齐 830011
  • 收稿日期:2021-07-16 修回日期:2021-12-23 出版日期:2022-03-15 发布日期:2022-03-30
  • 通讯作者: 曾凡江
  • 作者简介:余洋(1994-),男,硕士研究生,主要从事荒漠植物生理生态研究. E-mail: 2636173006@qq.com
  • 基金资助:
    国家基金委-新疆联合基金培育项目(U1903102);国家自然科学基金项目(41977050)

Stoichiometric characteristics of leaves and fine roots in Alhagi sparsifolia in response to the addition of nitrogen and water

YU Yang1,2,3,4(),ZHANG Zhihao1,2,3,YANG Jianming5,CHAI Xutian1,2,3,4,ZENG Fanjiang1,2,3()   

  1. 1. Xinjiang Key Laboratory of Desert Plant Roots Ecology and Vegetation Restoration, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China
    2. State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China
    3. Cele National Station of Observation and Research for Desert-Grassland Ecosystems, Cele 848300, Xinjiang, China
    4. University of Chinese Academy of Sciences, Beijing 100049, China
    5. Ecological Protection and Restoration Division of Forestry and Grassland Bureau of Xinjiang Uygur Autonomous Region, Urumqi 830011, Xinjiang, China
  • Received:2021-07-16 Revised:2021-12-23 Online:2022-03-15 Published:2022-03-30
  • Contact: Fanjiang ZENG

摘要:

氮素和水分是影响荒漠植物生长的重要因素,而全球变化主要驱动因素的氮沉降和干旱会直接改变土壤中这2种资源的可利用性。以塔克拉玛干南缘优势植物疏叶骆驼刺(Alhagi sparsifolia Shap.)一年生幼苗为研究对象,设置了盆栽试验。通过添加不同水平的N肥和水分,用于模拟不同水平的N沉降速率(0, 3.0, 6.0, 9.0 g·m-2·a-1)和水分条件(干旱和充分水),探究这2种因素对骆驼刺叶片与细根化学计量特征的影响。结果表明:(1) 除叶片P含量外,N和水分添加独立或交互作用影响骆驼刺叶片和细根的养分状况。干旱条件下,N添加显著降低了叶片N、Mn、Zn、Cu等元素含量(P<0.01),而在一定程度上提高了细根对这些元素的吸收;(2) 骆驼刺细根中富集着Mn、Zn、Cu、Fe等微量元素,而将N、P、K等大量元素更多地分配给叶片;(3) 干旱胁迫条件下施加3.0 g·m-2·a-1,水分充足条件下添加6.0 g·m-2·a-1或9.0 g·m-2·a-1,可以显著缓解骆驼刺细根的N限制(N:P<14);(4) 骆驼刺叶片和细根的营养元素在器官内和器官间存在复杂的相互作用,器官间的这种相互关系发生的比率大于器官内部,细根次之,叶片最低。这些结果表明骆驼刺在环境资源波动的背景下,能够协调地上和地下的养分关系;外源的N输入可以改善骆驼刺细根的养分状况,为荒漠植被修复和养分高效管理提供了科学参考。

关键词: 疏叶骆驼刺, 氮素和水分, 荒漠植物, 氮沉降, 叶片与细根, 化学计量特征, 养分状况

Abstract:

Nitrogen and water are important factors affecting the growth of desert plants; nitrogen deposition and drought, the main driving factors of global climate change, will directly change the availability of these two resources in soil. Presently, our understanding of how N deposition and drought affect the chemometric characteristics of desert plants remains limited. Thus, a pot experiment was conducted on 1-year-old seedlings of Alhagi sparsifolia, a dominant plant of the southern edge of the Taklamakan Desert. Different amounts of N fertilizer and water were added to simulate different levels of the N deposition rate (0, 3.0, 6.0, and 9.0 g·m-2·a-1) and water conditions (drought or well-watered conditions) to explore the effects of these two factors on the stoichiometric characteristics of the leaves and fine roots of A. sparsifolia. The results show the following: (1) N and water addition independently or interactively affected the nutrient status of leaves and fine roots of A. sparsifolia, except for P content in leaves. Nitrogen addition significantly decreased the contents of N, Mn, Zn, and Cu in leaves under drought conditions but increased the absorption of these elements by fine roots to a certain extent; (2) microelements such as Mn, Zn, Cu, and Fe were enriched in the fine roots of A. sparsifolia, but macroelements such as N, P, and K were more distributed in the leaves; (3) applying 3.0 g·m-2·a-1 N under drought stress and adding 6.0 or 9.0 g·m-2·a-1 N under well-watered conditions can significantly alleviate the N limitation of fine roots of A. sparsifolia (N:P<14); (4) the nutrient elements of leaves and fine roots of A. sparsifolia have complex interactions within and between organs. The occurrence rate of this relationship between organs is greater than that within organs, followed by that in fine roots, and the lowest in leaves. These results show that A. sparsifolia can coordinate the relationship between aboveground and underground nutrients under the background of fluctuations in environmental resources. Exogenous N input can improve the nutrient status of fine roots of A. sparsifolia. These results provide further scientific reference for the efficient nutrient management and restoration of desert vegetation.

Key words: Alhagi sparsifolia, nitrogen and water, desert plants, nitrogen deposition, leaves and fine roots, stoichiometric characteristics, nutrient status