Staff Publications

Staff Publications

  • external user (warningwarning)
  • Log in as
  • language uk
  • About

    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

    We have a manual that explains all the features 

Record number 525477
Title Die Nichtaustauschbare Festlegung des Kalis im Boden
Author(s) Hauser, G.F.
Source University. Promotor(en): J. Hudig. - Wageningen : Veenman - 172
Publication type Dissertation, internally prepared
Publication year 1941
Keyword(s) bodem - kalium - absorptie - adsorptie - soil - potassium - absorption - adsorption
Categories Soil Fertility / Fertilizers, Fertilizer Application
Abstract Types of bonds between K and soil constituents were summarized with published data; Volk's remineralization model and a model of Gorbunov were rejected. Experimental results suggested that an equilibrium existed between exchangeable and unexchangeable K. Only soils with an inorganic colloid fraction could fix K in an unexchangeable form.

Fixation capacity was correlated with clay percentage.

Differences between river clay and marine clay were clarified by content of minerals low in K and by the influence of naturally occurring humic substances. Micaceous earth was especially K fixing while humic substances did not fix potassium but increased the capacity of minerals to fix K.

Distortion of the humic film by oxidation or a pH shift lowered the fixation capacity of soils. Adding artificial humic substances to soil did not restore fixation capacity but lowered it by blocking access to the grid.

Field trials showed that prolonged K consumption without replenishment enlarged the K-fixing capacity. On K-fixing soils, heavy K dressings had a transient effect, so a K dressing in autumn was purposeless. Fixation of K was so strong that even under heavy K dressings, there was no leaching of K.

Comments
There are no comments yet. You can post the first one!
Post a comment
 
Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.