NORMALIZED STABILITY INDEX AND MEAN WEIGHT
DIAMETER IN A COMBINED NITROGEN FERTILIZATION X
IRRIGATION EXPERIMENT ON HUNGARIAN CHERNOZEM
SOIL

Andrea HUISZ,Tibor TÓTH, Tamás NÉMETH


Abstract: Soil management and tillage practices could be remarkable stress factors on structure of soil which
might be ruined and therefore cause the reduction of crop yields. The effect of irrigation and fertilizers on soil
structure may be diverse and often contradictory. In contrary to the often proved soil structure disrupting
effect of irrigation, in our experiment, as the result of irrigation, increased aggregate water-stability was
observed. In unfavorable conditions, or in large accumulation, ammonium fertilizers may cause the disruption
of soil structural units, therefore decline of soil structure as it was observed in our experiment. These results
were compared with the Normalized Stability Index and Mean Weight Diameter of which the second one
showed significant differences among the treatments.