Joint International Conference on Long-term Experiments ...

agriculture in Hungary, especially sandy soils, which are very sensitive to
environmental effects and inefficient human treatment (Németh (1996)).
The formation and fate of soluble N-forms and its response to organic matter
mineralization is not obvious yet and often inconsistent despite the intensive research
(Lazányi et al. (2002)).
The aim of this paper is to present data on different easily mineralizable N-forms
of a long term field experiment (LTFE) by incubation and chemical method in the
Nyírség region, in Hungary.
MATERIALS AND METHODS
1. Soils and experimental designs
Sandy soils were sampled from the „Nyírlugos” long-term field experiment, which were
established in 1962. The “Nyírlugos” LTFE was set up on acidic brown forest soil with
alternating thin layers of clay substance „kovárvány” in the Nyírség region. The main
characteristics of the experimental soils are: pH(KCl) 4.5, humus 0.7%, CEC 5-10
mgeq/100 g in the ploughed layer. The topsoil was poor in all five macronutrients (N, P,
K, Ca, Mg) and the groundwater depth was 2-3 m (Kádár et al., 1999).
The “Nyírlugos” experiment is a long-term small-plot (50m 2 ) fertilisation and liming
experiment. The experiment consists of 32 treatments, 4 replications altogether 128 plot
experiments. The indicator plant is triticale since 1980.
Fertilisation and liming treatments in the experiment were changed several times in the
last few decades but the levels are constant since 1980 (Table 1.).
Table 1: Treatments of LTFE in “Nyírlugos”, since 1980
Treatments (kg/ha/year)
Levels N P2O5 K2O CaCO3 MgCO3
Control - - - - -
1 50 60 60 250 140
2 100 120 120 500 280
3 150 180 180 1000 -
Only ten (one-sided N- and N-combined) treatments are summarized in this paper.
Chosen treatments can be divided four groups according to applied nutrients and lime
(Table 2.) Soil samples were collected from 5 different places in each plot after harvest
of triticale, in August 1998 and 2001.
Table 2: Chosen treatments and their variations of “Nyírlugos”
Control group N group NPK group Limed group
N1 N2P2 N2P2 K2Ca2
Controls N2 N2K2 N2P2 K2 Mg2
N3 N2P2K2 N2P2 K2 Ca2 Mg2
227