Journal article

Publication year: 1996

Pages: 391-397

Journal: Journal of Plant Nutrition and Soil Science

Volume number: 159

Issue number: 4

ISSN: 0044-3263

Open access status: Bronze

DOI Link: https://doi.org/10.1002/jpln.1996.3581590413

Publisher: Wiley-VCH Verlag

Abstract: 

For investigation on the effects of higher ion concentrations in soils on results of EUF (electro-ultrafiltration), performed at constant current, a light soil (12% clay) was analyzed by adding increasing amounts of a NaCl solution to the soil slurry in the EUF middle cell. Recording the course of voltage and current through the EUF cell, it was found that,

1) a continuous decrease of electrode voltage occurs over extended time periods, when the electric conductivity of the soil was increased.

2) As a function of this voltage decline, the potassium concentration in the EUF-20 degrees C fraction was reduced, whereas in EUF-80 degrees C fraction higher amounts of potassium could be found.

3) Unlike at very high levels of electric conductivity, the total K extraction by EUF was nearly unaffected, because losses in K content in the fraction EUF-20 degrees C could be compensated by the fraction EUF-80 degrees C.

4) According to Nemeth and Ziegler (1988) the ratio of EUF-K-80 degrees C to EUF-K-20 degrees C should be between 0.1 and 0.2 for light, but about 0.6 for heavy soils. Under the influence of higher electric conductivities this figure for light soils, however, approached values for heavy soils.

5) Also, the contents of magnesium and calcium showed marked decreases at higher electric conductivities in the EUF-fractions a and b (= EUF-20 degrees C). Contrary to the total amount of extractable potassium, the total contents of magnesium and calcium, extractable by EUF, were markedly decreased by higher electric conductivities in the light soil.

It is recommended, that the parameters voltage and current should be considered in interpretations of EUF-fractions from soils with higher levels of electric conductivity.

Harvard Citation style: Pauler, B. and Neumann, K. (1996) Model experiments on the potassium release of soils with higher electric conductivities by electro-ultrafiltration (EUF), Journal of Plant Nutrition and Soil Science = Zeitschrift für Pflanzenernährung und Bodenkunde, 159(4), pp. 391-397. https://doi.org/10.1002/jpln.1996.3581590413

APA Citation style: Pauler, B., & Neumann, K. (1996). Model experiments on the potassium release of soils with higher electric conductivities by electro-ultrafiltration (EUF). Journal of Plant Nutrition and Soil Science = Zeitschrift für Pflanzenernährung und Bodenkunde. 159(4), 391-397. https://doi.org/10.1002/jpln.1996.3581590413