Journalartikel

Jahr der Veröffentlichung: 1989

Seiten: 337-343

Zeitschrift: Journal of Plant Nutrition and Soil Science

Bandnummer: 152

Heftnummer: 4

ISSN: 0044-3263

DOI Link: https://doi.org/10.1002/jpln.19891520401

Verlag: Wiley-VCH Verlag

Abstract: 
Experiments were carried out with four different soils (basaltic soil, C-horizon of a keuper, sea alluvium, and a podsolic brown earth from loess) to investigate whether the fractions of exchangeable K and HCl-soluble nonexchangeable K are decreased in root vicinity by the K uptake of ryegrass (Lolium perenne). After a growth period of 70 days with five cuts distinct K depletion profiles wee obtained showing that in the direct vicinity of the root the decrease in exchangeable K was the most pronounced. The K depletion in this fraction extended to 2 cm distance from the root zone. Also the concentration of HCl-soluble nonexchangeable K of the interlayers was decreased in root vicinity. It is assumed that the decrease in K concentration in soil solution is a prerequisite for the net release of interlayer K. The decrease in exchangeable K plus HCl soluble nonexchangeable K was equal to the amount of K taken up by the grass from the basaltic- and the alluvial soil. In the case of the podsolic brown earth and the keuper soil, however, much more K was taken up by the grass than was found in the decrease of exchangeable K plus HCl soluble nonexchangeable K. It is assumed that in these two soils the fraction of the HCl soluble K was more altered by the expansion of interlayers during the growth of rye-grass. The net release of interlayer K was neither related to the concentration of exchangeable K, HCl-soluble non-exchangeable K, the K fixation power nor the clay concentration. It is supposed that the net release of interlayer K also depends on clay mineral characteristics.

Harvard-Zitierstil: KONG, T. and STEFFENS, D. (1989) SIGNIFICANCE OF K-DEPLETION IN THE RHIZOSPHERE AND CLAY-MINERALS FOR THE RELEASE OF NONEXCHANGEABLE POTASSIUM AND ITS DETERMINATION WITH HCL, Journal of Plant Nutrition and Soil Science = Zeitschrift für Pflanzenernährung und Bodenkunde, 152(4), pp. 337-343. https://doi.org/10.1002/jpln.19891520401

APA-Zitierstil: KONG, T., & STEFFENS, D. (1989). SIGNIFICANCE OF K-DEPLETION IN THE RHIZOSPHERE AND CLAY-MINERALS FOR THE RELEASE OF NONEXCHANGEABLE POTASSIUM AND ITS DETERMINATION WITH HCL. Journal of Plant Nutrition and Soil Science = Zeitschrift für Pflanzenernährung und Bodenkunde. 152(4), 337-343. https://doi.org/10.1002/jpln.19891520401