Long-term static fertilization experiments at the Experimental Field in Skierniewice were designed using modern statistical methods. Experiments on 11 fields (A_1–8, AF_1–3 i D) were started in 1922 by Prof. Józef Mikułowski-Pomorski and on the other 8 fields (A_9–11 i E) in 1924 by Prof. Marian Górski. The first results of these experiments were obtained in 1923 and 1925, respectively. From the beginning until now the experiments are conducted in three (Fields A) or five replications (Fields E i D).

The major aim of long-term experiments is evaluation of different organic and mineral fertilization effect on crops and environment in different crop rotation systems. On the objects of these experiments following fertilization and crop rotation systems are conducted:

• mineral fertilization without FYM in arbitrary rotation with legumes on strongly acidic (Fields A_1–3 & AF_2–3) and slightly acidic soil (Field A_6–8),
• mineral fertilization with FYM in arbitrary rotation without legumes on strongly acidic (Fields A₄ & AF₁) and slightly acidic soil (Field A₅),
• mineral fertilization without FYM in arbitrary rotation with legumes on slightly acidic soil (Fields A_9–11),
• mineral fertilization with FYM every 5 years in 5-course rotation (Fields E_1–5),
• mineral fertilization only, FYM only or FYM with mineral fertilizers in monoculture of rye, potato (since 1923) and triticale (since 1990) (Fields D). MAP OF FIELD I

Mineral fertilizers, under all fertilization and crop rotation systems, are applied in the same doses. At the beginning of the experiments, fertilizers were applied in following doses: 30 kg N ha^-1, 30 kg P₂O₅ ha^-1 and 30 kg K₂O ha^-1. Mineral fertilizers doses used at present time are given below SCHEME OF FIELD I and they entered into force in the year 1976.

 

SCHEME OF THE FIELD I

Field name	Crop rotation and form of nitrogen			Fertilization1
A1-3	Arbitrary rotation without legumes	N-NH4NO3	without FYM	0 CaNPK NPK PK PN KN
A4			with FYM since 1992
AF2-3		N-(NH4)2SO4	without FYM
AF1			with FYM since 1992
A6-8		N-NH4NO3	without FYM	Ca CaNPK NPK CaPK CaPN CaKN
A5			with FYM since 1992
A9-12	Arbitrary rotation with legumes	N-NH4NO3	without FYM
E1-5	5-field course (spring barley, red clover, winter wheat, rye, potato + 30 t of FYM)	N-NH4NO3	with FYM
D5   D6   D7	Potato monoculture   Rye monoculture   Triticale monoculture2)	N-NH4NO3	with or without FYM	Ca CaNPK NPK CaPK CaPN CaKN CaNPK+FYM (30 t ha-1 every 4 years) Ca+FYM (20 t ha-1 year-1)

¹⁾ Doses since 1976: 1,6 t CaO ha^-1 every 4 years on A fields  and every 5 years on E fields,

90 kg N ha^-1, 26 kg P ha^-1, 91 kg K ha^-1

²⁾ Conducted from 1985 excluding Ca+FYM (20 t ha^-1 year^-1) treatment

 

Due to close distance between long-term experiments conducted at the Experimental Station in Skierniewice and the meteorogical station, it is possible to investigate with strong reliability the effect of climatic conditions on agricultural production.