Page 39 - Abstract book - TJSSF-2020

Thailand – Japan Student Science Fair 2020 (TJ-SSF 2020)
“Seeding Innovations through Fostering Thailand – Japan Youth Friendship”

Study of the effects of heavy metals on growth and comparison of
heavy metal adsorption efficiency of Large duckweed
(Spirodela polyrrhiza (L.) Schleid.)

Pachara Chaipinitnorachart , Tepprecha Teebunma
1
1
Advisors: Panupong Kampanit , Phakpoom Phraprasert
1
2

Princess Chulabhorn Science High School Chonburi
1
Burapha University
2

Abstract
The objective of this research was to compare the efficiency of heavy metal adsorption and study the
effect of heavy metals on the growth of duckweed (Spirodela polyrrhiza (L.) Schleid.) by using Large
duckweed from the dormitory pool at Princess Chulpabhorn Science High School Chonburi. The
experiment was divided into 2 steps. The first step was to study the adsorption efficiency of heavy
metals (Copper: Cu) of Large duckweed. The experiment was carried out by using 50 Large duckweed
/ experiment set in the copper (II) sulfate (CuSO4) solution at concentrations of 0.2M, 0.4M, 0.6M, 0.8M
and 1M, data were collected for 1, 3, 5 and 7 days. The experimental results of copper metal
continuously decreased. The adsorption of copper metal of Large duckweed was the most effective
adsorption at the concentration of 1M which could absorb copper by 0.00027%. The second step, study
the effects of heavy metals on the growth of Large duckweed from measuring the root length, the
average root length of Large duckweed increased and the average root length correlated with the
concentration of copper (II) sulfate solution over time. Including the determination of chlorophyll, A
and chlorophyll B by extracting with acetone. After that, the absorbance was measured and the amount
of chlorophyll A and chlorophyll B were increased after the experiment was completed. Research has
shown that Large duckweed are effective in absorbing heavy metals. And with a growing rate of growth
Therefore can be used as a prototype plant to absorb heavy metals in the environment.

Keywords: Large Duckweed, CuSO4, Heavy metal

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