Joint International Conference on Long-term Experiments ...

LONG-TERM EFFECT OF ORGANIC AND MINERAL FERTILIZATION ON
DIFFERENT SOIL-FERTILITY PARAMETERS
ABSTRACT
Sándor Hoffmann and Katalin Berecz
University of Pannonia, Georgikon Faculty of Agricultural Sciences
Deák F. str. 16, H-8360 Keszthely/Hungary
Eleven variations of farmyard manuring (FYM) and mineral fertilization treatments of a
long-term field trial have been selected for the present investigations. Attributes of
changes in soil fertility were investigated. FYM and equivalent NPK fertilization
resulted in similar pHH2O values, while FYM increased TOC content of the soil by 10%
as compared to equivalent NPK fertilizer. FYM increased K, while equivalent doses of
NPK fertilizer increased P content of soil to a higher degree, as compared to nil plot.
Yearly 14 t ha -1 FYM or equivalent NPK fertilizer kept soil P and K contents at the
range of “medium-well-supplied”. However, not even yearly 21 t ha -1 of FYM resulted
in maximum yields in 1998-2006. 35; 70 and 105 t FYM ha -1 5 year -1 increased grain
yields to a lesser extent (by 0.66, 1.44 and 0.85 t ha -1 , respectively), as compared to
equivalent NPK doses, which was mainly due to the better utilization of mineral
fertilizer. After harvesting all the plots contained relatively high amounts of nitrate in
the 0-300 cm soil layer. Nitrate content of the non-treated plot was considerably high as
well. Despite the low yield response to FYM-treatments, less nitrate was found in the
soil, than with mineral fertilization.
INTRODUCTION
Field experiments are essential means for studying the changes in soil fertility as
affected by different fertilization and farming systems. With changing economical and
social conditions and farming systems, also the judgement of the role of farmyard
manuring (FYM) kept changing. The effect of FYM on soil fertility is very different.
However, the nutrient content of FYM have the most direct and highest effect, which
can be compared to the effect of equivalent NPK fertilizer doses. This effectiveness is
influenced by various factors and it is generally lower, than in case of fertilizers with
the same active ingredients and equivalent doses. Nevertheless, this tendency may turn
with the increase of clay content in the soil (Sarkadi, 1993). The NPK fertilizer
equivalency of FYM can be determined not only in experiments comparing the effect of
FYM and NPK fertilizers of equivalent doses, but also in combined polyfactorial
experiments (Baldock and Musgrave, 1980; Bouldin et al., 1984), and the results are
nearly similar (Hoffmann, 1999). Many authors detected that the nutrient effect of FYM
can be fully substituted for fertilization (Stumpe et al., 2000), others founded that the
effect of fertilization is higher except for the case of very heavy soils (Árendás and
Csathó, 1994). On the other hand, the secondary effect of FYM, namely the increase in
general soil fertility is very important and it manifests itself in the structure, organic
matter composition and microbial activity of soil, and this effect can not be substituted
for mineral N-fertilization in many instances (Albert, 2001).
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