Premium
Influence of exchangeable potassium on soil erodibility
Author(s) -
Auerswald K.,
Kainz M.,
Angermüller S.,
Steindl H.
Publication year - 1996
Publication title -
soil use and management
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.709
H-Index - 81
eISSN - 1475-2743
pISSN - 0266-0032
DOI - 10.1111/j.1475-2743.1996.tb00531.x
Subject(s) - soil water , slurry , manure , potassium , topsoil , inceptisol , soil science , surface runoff , chemistry , environmental science , infiltration (hvac) , dispersion (optics) , agronomy , hydrology (agriculture) , environmental engineering , ecology , geology , materials science , physics , organic chemistry , optics , biology , geotechnical engineering , composite material
. Regular application of slurry manure in large quantities is thought to degrade soil structure and increase erodibility. One hypothesis links this to the large input of potassium which increases the exchangeable potassium percentage (EPP) and, thereby, dispersion. The effect of EPP on erodibility was quantified in three experiments. In the laboratory, eleven rainfall experiments were conducted using a silty topsoil from a typic Hapludalf which was fertilized to EPPs of 4 to 18%. Field rainfall experiments on 22 Inceptisols and Alfisols were used to examine whether the long‐term application of monovalent cations (Na + , K + and NH 4 + ) with slurry manure had changed soil properties, especially erodibility. In addition, erodibilities of 32 soils determined with natural and simulated rains were taken from literature. The experiments on these 65 soils together covered a wide range of soils, slopes and rainfalls. Dispersion by a large percentage of highly hydrated ions (K + , Na + ) reduced the infiltration rate faster, caused runoff up to 5 min earlier, and increased sediment concentrations by 15g/l compared to low EPP soils. These changes increased soil erodibility of the Universal Soil Loss Equation (USLE) by 0.021 t × h/N × ha (where N = Newtons) for each 1% increase in EPP + ESP (exchangeable sodium percentage). The ESP contributed little to this increase as ESP was less than 1/10 of EPP in the experiments. Fields with long‐term manure application had similar chemical, physical and microbiological soil properties as fields without slurry manure except for slightly greater pH (+ 0.6) and P (+ 17 mg/kg) values. We conclude that, as long as the potassium input and output are balanced, the long‐term use of slurry manure does not increase erodibility.