W. Aufhammer et E. Kubler, NITRATE AND PHOSPHATE VALUES OF SOILS IN RELATION TO SOIL SAMPLING METHODS, Agribiological research, 50(3), 1997, pp. 215-224
In order to get nitrate and phosphate values of soils, investigations
were conducted to test the suitability of different soil sampling meth
ods. Including two one-piece borer types eight different soil sampling
methods (hand/hammer, Dutzi, N-caterpillar, Geonor) were examined in
relation to control samples, drawn manually by a three-piece borer. So
il samples (0-90 cm) were drawn from two fields with different soil ch
aracteristics at two different dates. In all cases hand/hammer-methods
resulted in a remarkable overestimation of the nitrate and the phosph
ate concentration in soil samples. Sampling methods, which realize a c
ombination of high blow frequency and low energy input per blow allow
values not significantly different form control levels. Even those sys
tems are not able to eliminate critical effects of physical soil trait
s. The effects of different borer types were of minor importance.