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Biomass measurement of living Lumbriculus variegatus with impedance spectroscopy Cover

Biomass measurement of living Lumbriculus variegatus with impedance spectroscopy

Open Access
|Dec 2014

Figures & Tables

Fig. 1

Equivalent circuit (a), exemplary impedance (b) and phase spectra (c) of tap water and worm biomass in tap water, incl. fitting results. R, W and CPE are resistance, Warburg impedance and constant phase element simulating electrode polarization and ion migration; Caq and Raq the capacitance and resistance of buffered tap water when no current runs through the worms; Cw and Rw are capacitance and resistance of the worms, and Caq,w and Raq,w represent capacitance and resistance of the water between worms and electrodes.
Equivalent circuit (a), exemplary impedance (b) and phase spectra (c) of tap water and worm biomass in tap water, incl. fitting results. R, W and CPE are resistance, Warburg impedance and constant phase element simulating electrode polarization and ion migration; Caq and Raq the capacitance and resistance of buffered tap water when no current runs through the worms; Cw and Rw are capacitance and resistance of the worms, and Caq,w and Raq,w represent capacitance and resistance of the water between worms and electrodes.

Fig. 2

Lumbriculus variegatus in the open measuring cell
Lumbriculus variegatus in the open measuring cell

Fig. 3

Impedance (a) and phase (b) against frequency plotted for 6 different amounts of living Lumbriculus variegatus fed with TetraMin® measured in buffered tap water. The two evaluation frequencies and the contribution of electrode polarization to the phase shift are marked grey.
Impedance (a) and phase (b) against frequency plotted for 6 different amounts of living Lumbriculus variegatus fed with TetraMin® measured in buffered tap water. The two evaluation frequencies and the contribution of electrode polarization to the phase shift are marked grey.

Fig. 4

Comparison of impedance (a) and phase (b) of buffered tap water before and after 60 minutes exposure to living aquatic worms.
Comparison of impedance (a) and phase (b) of buffered tap water before and after 60 minutes exposure to living aquatic worms.

Fig. 5

Phase response at 90 kHz against worm biomass of two different kinds of Lumbriculus variegatus measured in tap water. The two groups of worms were fed with TetraMin® and secondary potato sludge, respectively.
Phase response at 90 kHz against worm biomass of two different kinds of Lumbriculus variegatus measured in tap water. The two groups of worms were fed with TetraMin® and secondary potato sludge, respectively.

Fig. 6

Phase response per mg of worm for 6 groups of differently sized groups of worms from different diets at 440 Hz. Diets from left to right: TetraMin® / starch mix COD/N=37; TetraMin® / starch mix COD/N=56; TetraMin® pure; Okara; soy meal; chlorella. Error bars are due to worm weight variation (abscissa) and measurement error (ordinate), respectively.
Phase response per mg of worm for 6 groups of differently sized groups of worms from different diets at 440 Hz. Diets from left to right: TetraMin® / starch mix COD/N=37; TetraMin® / starch mix COD/N=56; TetraMin® pure; Okara; soy meal; chlorella. Error bars are due to worm weight variation (abscissa) and measurement error (ordinate), respectively.

Fig. 7

Phase response per mg of worm for 6 groups of differently sized groups of worms at 90 kHz. Diets from left to right: TetraMin® / starch mix COD/N=37; TetraMin® / starch mix COD/N=56; TetraMin® pure; Okara; soy meal; chlorella. Error bars are due to worm weight variation (abscissa) and measurement error (ordinate), respectively. The dotted grey lines are a visual aid showing the upper and the lower end of the measurement error.
Phase response per mg of worm for 6 groups of differently sized groups of worms at 90 kHz. Diets from left to right: TetraMin® / starch mix COD/N=37; TetraMin® / starch mix COD/N=56; TetraMin® pure; Okara; soy meal; chlorella. Error bars are due to worm weight variation (abscissa) and measurement error (ordinate), respectively. The dotted grey lines are a visual aid showing the upper and the lower end of the measurement error.

Covariance analysis of the regression slopes of mass (m) against phase (φ) at 90 kHz of worms fed with either TetraMin® (T) or secondary potato sludge (S) as shown in Fig_ 5_ SD means standard deviation_

TetraMin® (T)Sec. potato sludge (S)
n18.0030.00
meanm / mg140.00142.00
SDm / mg118.27110.09
meanφ / °-4.11-4.50
SDφ / °3.313.63
r-1.00-1.00
t-46.18-65.32
p< 0.0001< 0.0001
Slope k / (°/mg)-0.0278-0.0328
Const c / °-0.22270.163
Com. Slope / (°/mg)-0.0308
Com. const. / °-0.534
DOI: https://doi.org/10.5617/jeb.934 | Journal eISSN: 1891-5469
Language: English
Page range: 92 - 98
Submitted on: Sep 8, 2014
Published on: Dec 3, 2014
Published by: University of Oslo
In partnership with: Paradigm Publishing Services
Publication frequency: 1 issue per year

© 2014 Martina Sammer, Bob Laarhoven, Ernest Mejias, Doekle Yntema, Elmar C. Fuchs, Gert Holler, Georg Brasseur, Ernst Lankmayr, published by University of Oslo
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.