Acta Agrestia Sinica

Acta Agrestia Sinica ›› 2017, Vol. 25 ›› Issue (5): 1145-1151.DOI: 10.11733/j.issn.1007-0435.2017.05.032

Previous Articles     Next Articles

The Impedance Magnitude of Material Around Root Affects the Validity of the Electrical Capacitance Method

PENG Yuan-yuan1, CAO Yang2,3, CHEN Yun-ming2,3   

  1. 1. Institute of Soil and Water Conservation, Northwest A & F University, Yangling, Shaanxi Province 712100, China;
    2. Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi Province 712100, China;
    3. State Key Laboratory of Soil Erosion and Dry land Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi Province 712100, China
  • Received:2016-09-30 Revised:2017-08-19 Online:2017-10-15 Published:2018-01-25

根系周围介质阻抗影响电容法测量植物根系有效性

彭源远1, 曹扬2,3, 陈云明2,3   

  1. 1. 西北农林科技大学水土保持研究所, 陕西 杨凌 712100;
    2. 西北农林科技大学水土保持研究所黄土高原土壤侵蚀与 旱地农业国家重点实验室, 陕西 杨凌 712100;
    3. 中国科学院水利部水土保持研究所, 陕西 杨凌 712100
  • 通讯作者: 陈云明,E-mail:ymchen@ms.iswc.ac.cn
  • 作者简介:彭源远(1992-),男,湖南涟源人,硕士,主要从事电容法测量植物根系机理研究,E-mail:peyikpeng@163.com
  • 基金资助:

    中央高校基本科研业务费专项（2014YB056）资助

PDF

Abstract:

In order to examine the relationships between the eigenvalue (surface area, length, fresh weight) of plant root and the electric capacitance, and to address the effect of the impedance value of medium around the roots on the validity of the measurement results, hydroponic and pot experiments were controlled in this research. Scindapsus was taken as the research object for hydroponic experiment, and about 2/3 root was immersed into the solution and the root was marked at solution surface. After the capacitance measurement was completed, the roots were cut into two parts (above the liquid level and below the liquid level) at the mark. The relation between these two parts of roots and capacitance was analyzed respectively. Maize was taken as the object for pot experiment. Soil water moisture and soil solution ion concentration were controlled to get different groups with different impedance soil. The relationship between the capacitance measured in different impedance soil and the corresponding surface of root was analyzed. The results showed that:there was significant linear relationship between scindapsus roots above the liquid level and the measured capacitance value; only under the conditions of the pot experiment with distilled water in soil at water content of 24.86%, and the diluted Hoagland nutrient solute (1/1 000) in soil at water content of 25.18%, the measured capacitance value had significant linear relationship with the values of maize root surface area. Its showed that the capacitance method could be used to measure plant root characters, but the impedance magnitude of medium that around the roots is an important factor affecting the validity of the capacitance method.

Key words: Capacitance method, Root capacitance, Root system, Masking action

摘要：

为检验电容法能否用于测量植物根系特征值（表面积、长度、鲜重）以及根系周围介质阻抗大小是否影响测量结果的有效性。本研究进行水培、盆栽两项试验，水培试验以绿萝（Epipremnum aureum）为研究对象，将根系约2/3部分浸入溶液中，标记液面与根系接触位置，测量其根系电容值，在标记处将根系剪成液面上、液面下两部分，分别分析电容值与这两部分特征值的关系。盆栽试验以玉米（Zea mays L.）为研究对象，通过控制土壤含水率和土壤溶液离子浓度，得到土壤阻抗值不同的试验组，分别分析不同阻抗条件下测得的电容值与根系特征值之间的关系。结果表明：水培试验测得的电容值只与液面以上绿萝根系特征值存在显著的线性关系；盆栽试验只在蒸馏水浇灌、土壤含水率为24.86%的实验组和1 000倍稀释霍格兰德营养液浇灌、土壤含水率为25.18%的试验组中，测得的电容值与玉米根系表面积存在显著线性关系，其试验组中其他二者相关性不显著。说明电容法能够用于测量植物根系特征值，但根系周围介质阻抗是影响电容法有效性的重要因素。

关键词: 电容法, 根系电容, 根系, 掩蔽作用

CLC Number: