Abstract. The article presents data from a study comparing the influence on plant productivity of three different farming systems – ecological, sustainable and chemical – and the use of various plants grown for green manure. Crops were lupine, white mustard and red clover. Calculations of the nutritional content of the soil in the experiments show that various crop rotations (treatments) affect the phosphorus and potassium balance. The data indicate that productivity of plant rotations depends on the plants cultivated and the applied farming system. In all farming systems, the highest yield was achieved cultivating plants after fertilization with green manure (lupines and white mustard). The results of the experiments show that crop rotations result in negative nitrogen, phosphorus (except in sustainable and chemical farming systems) and potassium balance in the soil. Crop rotations had no effect on the soil acidity and increased total nitrogen and organic carbon content in the soil. The amount of phosphorus in the soil increased in all farming systems; potassium increased only in the sustainable and chemical farming systems. Data indicating the number of micromycetes, organic and mineral nitrogen assimilating bacteria in the rizosphere soil of various grown plants are also presented.

Absract. Soil organic carbon (SOC) and soil organic matter (SOM) contents of Estonian grassland soils are analysed in 20 soil groups using data from the database PEDON and CATENA. The SOC and SOM concentrations (g kg^-1) and pools (Mg ha^-1) for upland mineral soils (Leptosols, Cambisols, Luvisols, Albeluvisols, Regosols; total 9 groups), lowland mineral soils (Gleysols, Fluvisols; 9 groups) and wetland organic soils (Histosols; 2 groups) are given separately for humus cover (HC) and soil cover (SC). The SOC and SOM pools for the entire Estonian grasslands were calculated on the basis of different soil types, morphological characteristics and distribution superficies. It was concluded that in Estonian grasslands SC 39.9±8.0 Tg of organic carbon is sequestered, 76.2% of which is found in HC and 23.8% in subsoils. Grassland SOC is sequestered in 69.1±12.6 Tg of SOM. A quality analysis of humus covers of grassland soils (evaluated from the pedo-ecological perspective) distinguished 5 quality groups and 15 subdivisions.

A. Sakalauskas¹, E. Šarauskis¹, A. Jasinskas¹, K. Romaneckas² and E. Vaiciukevičius^1
 
1Department of Agricultural Machinery, Lithuanian University of Agriculture, Studentu St. 15A, LT-53361 Kauno r., Lithuania; e-mail: ZUM.katedra@lzuu.lt
²Department of Soil Management, Lithuanian University of Agriculture, Studentu St. 11, LT-53361 Kauno r., Lithuania; e-mail: Kestas.romaneckas@lzuu.lt

Abstract. This paper presents the investigation of the technological process of operation of special type sugar beet seed pressure rollers and the experimental trial results of tests carried out in various soils at Hohenheim University. Pressure rollers are mounted behind the seeder coulters, improving the contact between sugar beet seeds and the soil and, in addition, improving seed germination ability. But pressure rollers of conventional sugar beet seeders used for sowing tilled and cultivated soils cannot always be used for seed pressing in non-ploughed and uncultivated soils. The main design parameters of the pressure rollers of sugar beet seeds are diameter, width, the number of rollers and fingers, mass, etc. The even pressing of seed, furrow bed profile, its hardness, seed damage and gravity, etc. depend on the above mentioned parameters. The theoretical investigations proved that the pressure rollers should be mounted on the seeder unit with the help of hinges. As a result, when the sugar beet seeds were sown in non-ploughed soils, the pressure force onto the soil would depend on the gravitational force The diameter of the pressure rollers should be not less than 180 mm in order to press the seeds into the soil to a depth of about 3 mm and ensure their good contact with the soil. The experimental trials revealed that the narrow disk pressure roller of 220 mm diameter and 15 mm width introduces the seeds of sugar beet into the hard soil of 0.4 and 0.9 MPa and satisfies the conditions of good seed and soil contact. The disk pressure roller with fingers is made of two disks; each 17-finger disk introduces sugar beet seeds by 2 mm shallower than the narrow one and forms waves in the furrow bottom. When the finger-type pressure roller has been pulled through 0.4 – 0.9 MPa hardness soil the recommended force should be from 0.004 to 0.011 kN greater than using the narrow pressure roller.

Key words: design of pressure roller, sugar beet, furrow bottom, soil hardness, gravitational force

The effect of grassland utilisation on physicochemical properties of peat-muck soils and species composition of sward
 
M. Kulik, R. Baryła and M. Warda
 
Department of Grassland and Green Forming, Agricultural University of Lublin, Akademicka 15, 20-950 Lublin, Poland, e-mail: mariusz.kulik@ar.lublin.pl

Abstract. The aim of these studies was to estimate the influence of utilisation or its lack on the changes of physicochemical properties of peat-muck soils as well as on the species composition of sward. Studies were carried out on the peatland complex located in the Pojezierze Łęczyńsko-Włodawskie (Lake District), in south-eastern Poland. This complex spreads over a wide area on both sides of the central segment of the Piwonia River. The fen was meliorated and cultivated from 1964–1966. At present, the soils of this grassland complex belong to the type of muck soils and the subtype of peat-muck soils (Mt II). Grasslands situated on the left side of the river were systematically utilised as pastures and meadows. Experiments investigating the persistency of grass-legumes swards were located in this part of the grassland and were carried out in 1995–2005. During the ten-year study controlled fertilisation (N - 40, P - 31 and K - 100 kg ha^-1) was employed. Pasture sward was grazed by Limousine cattle 4–5 times during the grazing season; meadows were cut three times. The meadows on the right side of the Piwonia River were mowed until 1995. Since that time, they have been used extensively (with only one or no cutting in the growing season). Important changes in the sward composition and its floristic diversity were confirmed, particularly on the meadow without utilisation. Furthermore, there were observed significant changes in physicochemical properties of peat-muck soils which were characterized by the significantly highest bulk density as well as the lowest content of organic matter in comparison to meadow and pasture utilisation. The swards of the used pasture and meadow were characterized by better species composition than the meadow without utilisation, where a high proportion of tufted hair-grass as well as herbs and weeds were noted.

Key words: peat-muck soil properties, species composition, manner of grassland utilisation

Mobilization of substances in peat soils and their transfer within the groundwater and into surface water
 
A. Sapek, B. Sapek, S. Chrzanowski and J. Jaszczyński
 
Institute for Land Reclamation at Falenty PL-05-090 Raszyn; e-mail: a.sapek@imuz.edu.pl; telephone (48 22) 720 05 31; fax (48 22) 628 37 63

Abstract. The behaviour of nitrate, ammonium, phosphate and dissolved organic carbon (DOC) in the system of groundwater and surface water at a peat soil site has been studied. Data were collected during 2000–2005 and comprised the substance concentrations in groundwater samples taken separately from peat and mineral horizons and in surface water samples from the bordering drainage channels. Primary attention has been focused on the time and direction of the flux of these substances. The study area was part of Kuwasy Bog located in the Biebrza River Basin in north-eastern Poland. The main factor influencing the concentration of phosphate and ammonium in surface- and groundwater from the peat soil site were changes in the groundwater table. Lowering the water table in late summer mobilized phosphate and ammonium in peat groundwater. The released substances were transferred, with some delay, into deeper groundwater layers and further to drainage channels. Consequently, late summer and early autumn are the sole periods when these substances may be leached from the peat soils in question. Nitrates from peat soils reached only deeper layers of groundwater, but with an evident decline in their concentration. Hence, the possibility of nitrate losses from peat soils into the surface water is not great. Concentration of DOC in the drainage channel water increased in autumn with only weak relation to its concentration in both types of groundwater.

Key words: nitrogen compounds, phosphate, dissolved organic carbon, peat soil, groundwater, surface water

Chemical properties of different peat-moorsh soils from the Biebrza River Valley
 
L. Szajdak¹, T. Brandyk² and J. Szatyłowicz<sup>2

1</sup>Research Centre for Agricultural and Forest Environment, Polish Academy of Sciences, ul. Bukowska 19, 60-809 Poznan, Poland, szajlech@man.poznan.pl
²Department of Environmental Improvement, Warsaw Agricultural University, ul. Nowoursynowska 159, 02-776 Warsaw, Poland

Abstract. The relationship between soil structure and the ability of soil to stabilize soils organic matter is a key element in soil C dynamics. In this investigation the chemical properties were determined for three different peat-moorsh soils – Czarna Wieś, Otoczne and Kwatera 17 located in the Biebrza River Valley in Poland. Each considered soil, utilised as meadow, was sampled at two depths. The measured concentrations of total organic carbon in the considered soils ranged from 37.19% to 45.58%. Generally, a decrease of total organic carbon concentration with the depth of profiles was observed. The contents of dissolved organic carbon in the soils ranged from 5.34 to 19.39%. The quantities of dissolved organic carbon decreased simultaneously with E₄/E₆ values with the increasing depth of the soil profiles.

Key words: peat-moorsh soils, TOC, DOC, E₄/E₆

Occurrence of IAA auxin in some organic soils
 
L. Szajdak¹ and V. Maryganova^2
 
1Research Center for Agricultural and Forest Environment, Polish Academy of Sciences, ul. Bukowska 19, 60-809 Poznań, Poland, e-mail: szajlech@man.poznan.pl
²Institute for Problems of Natural Resources Use and Ecology, National Academy of Sciences of Belarus, 10 Staroborisovsky Trakt, 220114 Minsk, Belarus, e-mail: peatland@ns.ecology.ac

Abstract. The estimation of the quantities of auxin indole-3-acetic acids (IAA) and the composition of humus substances in peats and sapropels from Belarus and in secondary transformed peat-moorsh soils from Poland was demonstrated In high-moor peats the highest contents of IAA and humus substances was proved and ranged from 124.4 to 210 μg kg^-1. The contrary was found for low-moor peat. In these raw materials the quantities of IAA ranged from 57.9 to 134.3 μg kg^-1. In secondary transformed peat–moorsh soils the contents of IAA ranged from 69.3 to 186.1 μg kg^-1. A directly proportional relationship between the concentrations of IAA in peats and humus substances as well as total and dissolved organic carbon was observed. The correlations coefficients among these parameters ranged from 0.692 to 0.793. The concentrations of IAA in sapropels were similar to those determined in high-moor peats and ranged from 190 to 374 μg kg^-1 μg kg^-1.

Key words: peat, sapropel, humic substances, auxin, indole-3-acetic acid

Impact of secondary transformation of peat-moorsh soils on the decrease of nitrogen and carbon compounds in ground water
 
L. Szajdak¹, M. Szczepański¹ and A. Bogacz^2
 
1Research Centre for Agricultural and Forest Environment, Polish Academy of Sciences, ul. Bukowska 19, 60-809 Poznan, Poland, szajlech@man.poznan.pl
¹Institute of Soil Science and Agricultural Environment Protection, Wrocław University of Environmental and Life Sciences, ul. Grunwaldzka 53, 50-357 Wrocław, Poland, adam@ozi.wroc.pl

Abstract. The study of peatland is used to show the water quality functioning with respect to different forms of nitrogen and carbon. In this paper, the purification of ground water by the transect of 4.5 km length consisting of organic soils (peat-moorsh soils) was investigated. The transect is located in the Agroecological Landscape Park in Turew, 40 km South-West of Poznań, West Polish Lowland, along the Wyskoć ditch. In the study, pH, the contents of total and dissolved organic carbon, total nitrogen, N-NO₃^-, N-NH₄⁺ were measured. Additionally C/N factors of peats were estimated. The investigation has shown the impact of the peatland located on the secondary transformed peat-moorsh soils on the changes of total nitrogen, ammonium, and nitrates as well as total and dissolved organic carbon in ground water. Peatland decreases the concentration of the following compounds in ground water: nitrates 38.5%, N-organic 10%, N-total 24.5%, ammonium 38.7%, dissolved total carbon 33.1%, dissolved total inorganic carbon 10%, dissolved organic carbon 57.5%.

Key words: secondary transformation of peat, N-total, N-NO₃^-, N-NH₄⁺, forms of organic carbon