Sains Malaysiana 50(9)(2021): 2499-2510

http://doi.org/10.17576/jsm-2021-5009-01

Influence of Various Gauge Lengths, Root Spacing and Root Numbers on Root Tensile Properties of Herbaceous Plants

(Pengaruh Pelbagai Panjang Tolok, Jarak Akar dan Nombor Akar pada Sifat Tegangan Akar Tumbuhan Herba)
               
          

CHAOBO ZHANG*, XIAOYU MA, YATING LIU & JING JIANG

College of Water Resources Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China

Diserahkan: 5 April 2020/Diterima: 2 Januari 2021

Abstract

The mechanical properties of root system play an important role in soil reinforcement by plants. Root tensile properties are affected by many factors. It is necessary to explore the mechanical properties of root system and the influencing factors. In this study, tensile tests were conducted on roots of Kochia scoparia (L.) Schrad and Artemisia sacrorum Ledeb to study root tensile properties, including maximum tensile force, tensile strength and elastic modulus under the three factors, gauge length (50, 100, 150, and 200 mm), root spacing (0, 1, and 2 cm) and root number (single root, double roots, and triple roots). The results showed that the maximum tensile force, tensile strength, and elastic modulus of the roots decreased with increasing gauge length in power functions. Under 100 mm gauge length, the maximum tensile force, tensile strength and elastic modulus decreased with increasing root spacing, but the effect of root spacing considered in this study on the maximum tensile force and tensile strength was not significant. Besides, with increasing root number, the maximum tensile force increased, tensile strength, and elastic modulus decreased. These findings stretched our understanding of the relationship between gauge length, root spacing and root number on root tensile characteristics, and provided the necessary data basis for root tensile properties and soil reinforcement by plants.

Keywords: Gauge length; root mechanical properties; root number; root reinforcement; root spacing

Abstrak

Sifat mekanik sistem akar memainkan peranan penting dalam pengukuhan tanah oleh tanaman. Sifat tegangan akar dipengaruhi oleh banyak faktor. Adalah perlu untuk mengkaji sifat mekanik sistem akar dan faktor yang mempengaruhinya. Dalam kajian ini, ujian tegangan dilakukan pada akar Kochia scoparia (L.) Schrad dan Artemisia sacrorum Ledeb untuk mengkaji sifat tegangan akar, termasuk daya tegangan maksimum, kekuatan tegangan dan modulus elastik di bawah tiga faktor, panjang tolok (50, 100, 150 dan 200 mm), jarak akar (0, 1 dan 2 cm) dan nombor akar (akar tunggal, akar berganda dan akar tiga). Hasil kajian menunjukkan bahawa daya tegangan maksimum, kekuatan tegangan dan modulus elastik akar menurun dengan peningkatan panjang pengukur dalam fungsi daya. Di bawah panjang tolok 100 mm, daya tarik maksimum, kekuatan tegangan dan modulus elastik menurun dengan peningkatan jarak akar, tetapi pengaruh jarak akar yang dipertimbangkan dalam kajian ini terhadap daya tegangan maksimum dan kekuatan tegangan tidak signifikan. Selain itu, dengan bertambahnya bilangan akar, daya tarik maksimum meningkat, kekuatan tegangan dan modulus elastik menurun. Penemuan ini meluaskan pemahaman kami tentang hubungan antara panjang tolok, jarak jarak dan nombor akar pada ciri tegangan akar dan menyediakan asas data yang diperlukan untuk sifat tegangan akar dan pengukuhan tanah oleh tanaman.

Kata kunci: Jarak akar; nombor akar; panjang tolok; peneguhan akar; sifat mekanikal akar

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*Pengarang untuk surat-menyurat; email: zhangchaobo@tyut.edu.cn