Volume 6 (2008)
  Number 1

Contents


Pages

5-14 R. Aavola and M. Kärner
Nitrogen uptake at various fertilization levels and cutting frequencies of Lolium species
Abstract |

Nitrogen uptake at various fertilization levels and cutting frequencies of Lolium species

R. Aavola¹ and M. Kärner²

¹Jõgeva Plant Breeding Institute, Aamisepa 1, 48309 Jõgeva, Estonia;e-mail: rene.aavola@jpbi.ee
²Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences,Kreutzwaldi 5, 51014 Tartu, Estonia; e-mail: malle.karner@emu.ee

Abstract:

A field trial was carried out in 1999–2000 to identify optimal combinations of compound fertilizer rates and defoliation frequencies in perennial ryegrass cv. Raidi (diploid) and Raite (tetraploid) and Italian ryegrass cv. Talvike (tetraploid), to enable the nitrogen (N) requirements of dairy cows to be met. The study aimed at estimating the N utilization in the swards subjected to 6 cycles of simulated grazing or cutting 4 times for silage. N application rates were changed from 0–500 kg ha-1 by 100 kg in the former and from 0–400 by 80 kg ha-1 in the latter harvest regime. Increasing the rate of fertilizer increased the N concentrations and yields. Applying N 300 to ryegrasses defoliated at tillering to stem elongation stage allowed assuring minimum N content in the forage dry matter (2.2%) while at N 500 the upper level (2.7%) was exceeded. The ryegrass plants took up less N than was applied with the compound fertilizer. Increasing the defoliation frequency of grass had a positive effect on N content of the forage, but had inconsistent or no effect on improving N uptake from fertilizer and soil. Perennial ryegrass cultivars were more efficient than Italian ryegrass in taking up N from the soil and fertilizer at simulated grazing. Cutting 4 times a year at moderate to high fertilizer rate applications did not reveal a distinct superiority in N absorption of a particular cultivar, but Italian ryegrass had the best N uptake potential from N deficient soil.

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15-25 Manisha Basu and P. B. S. Bhadoria
Performance of groundnut (Arachis hypogaea Linn) under nitrogen fixing and phosphorus solubilizing microbial inoculants with different levels of cobalt in alluvial soils of eastern India
Abstract |
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Performance of groundnut (Arachis hypogaea Linn) under nitrogen fixing and phosphorus solubilizing microbial inoculants with different levels of cobalt in alluvial soils of eastern India

Manisha Basu¹* and P. B. S. Bhadoria¹

¹Department of Agricultural and Food Engineering, Indian Institute of Technology,Kharagpur-721 302, West Bengal, India
*Corresponding author: 1Department of Agricultural and Food Engineering,Indian Institute of Technology, Kharagpur-721 302, West Bengal, India;e-mail: basu.manisha@gmail.com; tel.: +919732654642

Abstract:

A field experiment was conducted for three years to evaluate the performance of groundnut under alluvial soil of eastern India with different types of inoculants such as Rhizobium and phosphobacterium inoculants, no inoculant, and different levels of cobalt ( 0.21 and 0.42 kg ha-1). Results indicated that Rhizobium inoculant promoted higher yield and nutrient uptake as compared to phosphobacterium. Kernel yield, averaged across three levels of cobalt, was recorded to be highest for Rhizobium inoculant, which was 16.50% and 10.72% higher over no inoculant and phosphobacterium inoculant respectively. Cobalt at the rate 0.21 kg ha-1 proved to be better as compared with other doses of cobalt and resulted in 10% higher kernel yield over no cobalt application. Among different treatment combinations, integrated application of Rhizobium + cobalt at the rate 0.21 kg ha-1 resulted in greater yield than that of other combinations, followed by phosphobacterium inoculant with the same dose of cobalt application. The yield and uptake of N, P and K by groundnut was significantly higher in the treatments receiving both inoculants and cobalt applied at 0.21 kg ha-1 than individual application of either inoculants or cobalt. The beneficial effect of application of microbial inoculants and cobalt was also reflected on the soil fertility status.

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27-35 L. Buskienė and N. Uselis
The influence of nitrogen and potassium fertilizers on the growth and yield of raspberries cv. ‘Polana’
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The influence of nitrogen and potassium fertilizers on the growth and yield of raspberries cv. ‘Polana’

L. Buskienė¹ and N. Uselis²

¹Lithuanian Institute of Horticulture, LT–-54333 Babtai, Kaunas distr., Lithuania; e-mail:institutas@lsdi.lt
²Lithuanian Institute of Horticulture, LT–-54333 Babtai, Kaunas distr., Lithuania; e-mail:n.uselis@lsdi.lt

Abstract:

The experiment was carried out from 1998–2001 at the Lithuanian Institute of Horticulture, according to the scheme: N60 (control); N60K90; N90; N90K130; N120; N120K180; N150;N150K240. The soil was Epicalcari – Endohypogleic cambisol, clay loam, containing 7.2% oforganic matter, 140 mg kg-1 P2O5, 125 mg kg-1 K2O, 11900 mg kg-1 CaO, 3040 mg kg-1 MgO,pHKCl –7.3.Primocane raspberries cv. ‘Polana’ fertilized with the largest amount of nitrogen fertilizers(N150) produced 20% more primocanes in comparison with the control (N60). Potassiumfertilizers increased the diameter of raspberry stems – fertilizing them with N120K180 stemdiameter resulted in an increase of 5.3%, with N90K130 and by 4.2% with N150K240 incomparison with the control.Primocane raspberries cv. ‘Polana’ fertilized with N120K180 gave the highest yieldincrement – 2.5 t ha-1, and, with N60K90 – 2.4 t ha-1 – in comparison with those fertilized onlywith nitrogen fertilizers (N60).When the rate of nitrogen fertilizers was increased from 60 to 90–150 kg ha-1, the nitrogencontent in the soil increased by approximately 25%. When the rate of potassium fertilizers was increased from 90 to 240 kg ha-1, potassium content in the soil increased to 33%. The content of potassium in raspberry cv. ‘Polana’ leaves significantly increased when fertilizing only with the highest rates of potassium fertilizers (N120K180 – N150K240) – by 12.1–19.7% – in comparisonwith control (N60).

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37-45 A. Jasinskas, G. Rutkauskas, B. Kavolėlis,A. Sakalauskas and E. Šarauskis
The energetic evaluation of technologies for fuel preparation from grass plants
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The energetic evaluation of technologies for fuel preparation from grass plants

A. Jasinskas¹, G. Rutkauskas¹, B. Kavolėlis¹,A. Sakalauskas² and E. Šarauskis²

¹Institute of Agricultural Engineering of Lithuanian University of Agriculture,Institute St. 20, LT-54132 Raudondvaris, Kaunas distr., Lithuania; e-mail: aljas@mei.lt
²Department of Agricultural Machinery, Lithuanian University of Agriculture,Studentu St. 15A, LT-53361 Akademija, Kaunas distr., Lithuania;e-mail: ZUM.katedra@lzuu.lt

Abstract:

The technologies of growing, harvesting and preparing for fuel traditional feed type grasses (the mix of cereal and legume grasses) and coarse-stemmed vegetative plants (topinambours and sunflowers) were evaluated and a rational technique was selected. The methods of energetic evaluation of fuel preparation technologies were reviewed.After energetic evaluation of the technologies it was estimated that the total energy inputof growing and harvesting grasses and legumes was equal to 8334 MJ ha-1, topinambour stems – 14378 MJ ha-1 and sunflower stems – 11324 MJ ha-1 respectively. The total energy input of growing and harvesting of traditional grasses was by 72% lower than that of topinambour stems and by 36% lower than the energy input required for fuel production from sunflower stems. From an energetic perspective, the technology of fuel preparation from traditional grasses is more advantageous than the technologies of fuel preparation from coarse-stemmed plants, specifically topinambour and sunflower stems.

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47-53 K. Kucińska, I. Pelc and J. Golba
Review of prospects of organic agriculture development in Poland determinate by consumer demands
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Review of prospects of organic agriculture development in Poland determinate by consumer demands

K. Kucińska, I. Pelc and J. Golba

Department of Agronomy, Faculty of Agriculture and Biology,Warsaw University of Life Sciences, Poland

Abstract:

Organic farming is developing dynamically in the European Union. In Poland its growth is much slower: the area of organic farms is still just a little above 1% of all utilised agricultural area. Research shows that the main obstacles to the dynamic development of organic farming are shortage of properly educated consumers and lack of an efficient distribution system of organic products in Poland and abroad. Regulations established before and after joining the European Union, in spite of some shortcomings, are not a barrier for the development of organic farming in Poland.

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55-65 G. Pupinis
Grain drying by use of changeable air flow method
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Grain drying by use of changeable air flow method

G. Pupinis

Institute of Agricultural Engineering, Lithuanian University of Agriculture Raudondvaris,LT-51132 Kaunas, Lithuania; e-mail: pupinis@mei.lt

Abstract:

The article describes a new energy saving method for drying grain. The idea of the method is that once moisture released from grain decreases, air discharge going through the grain is reduced as well. ´Roland´ variety of barley with 25% and 30% moisture content was used in the trial. It was dried with a changeable air discharge in order to maintain absorption qualities. After the drying process has begun, air flow to the grain is reduced in the process of drying as the relative moisture content of air passing through decreases. It has been established that the optimum initial air discharge is 800 m3 (t h)-1. During grain drying air discharge is reduced and it can be described by equation0,0114969.85xye−=, R2 = 0.8088.The scheme for a designed and manufactured trial device is presented. Intensity of airdischarge and dynamics of moisture absorption in a layer of dried grain have been established.

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67-78 O. Sada and B. Reppo
Indoor climate of pigsty with deep litter and liquid manure system in summer
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Indoor climate of pigsty with deep litter and liquid manure system in summer

O. Sada and B. Reppo

Institute of Technology, Estonian University of Life Sciences,Kreutzwaldi St. 56, 51014 Tartu, Estonia; e-mail: boris.reppo@emu.ee

Abstract:

Construction of big deep-litter pigsties and pigsties without litter (using liquid manure systems) is becoming more extensive. Due to lack of knowledge concerning animal-keeping in big pigsties, it has become necessary to study the work environment in pigsties and, in particular, their indoor climate. In order to determine the impact of the outdoor climate, different methods for animal-keeping and tending activities on indoor climate during summertime, the air temperature, relative humidity, air velocity and contents of oxygen, carbon dioxide and ammonia were measured on a daily basis at the height of 1.5 m from the floor above the pigsty in the centre of deep-litter (800 fattening pigs) and liquid manure system (600 young pigs) pigsties. Simultaneously outdoor air temperature and relative humidity were measured. Data Logger equipment with relevant sensors and Gas Monitor Pac III were used for studying the indoor climate. Hydrolog equipment was used for measuring the parameters of outdoor climate. Measurement results were processed by using computer programmes AMR Win Control, HW3 and MS Excel.It turned out that during summertime the indoor climate of pigsties was most affected byoutdoor climate and tending works. The daily average indoor temperature (17.04 and 17.60°C respectively; outdoor temperature, 18.15 and 8.75°C) and relative humidity (68.11 and 78.59% respectively; outdoor relative humidity, 71.88 and 84.19%) remained within recommended limits for animals in the deep-litter pigsty and in the pigsty without litter. However, partial floor heating had to be used in the morning in order to ensure optimum indoor temperature and relative humidity in the pigsty for young pigs. Due to good ventilation in the pigsties the daily average contents of carbon dioxide (0.06 and 0.07%) and ammonia (20.9 and 8.7 ppm) remained within standard limits. Ammonia content in pigsties was higher during tending works, reaching 43 and 27 ppm. As a result of the study, the graphical and empirical relationship was determined between ammonia concentration and indoor air both in terms of air temperature and combined effect of temperature and relative humidity.

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79-90 R. Sayar, H. Khemira, A. Kameli and M. Mosbahi
Physiological tests as predictive appreciation for drought tolerance in durum wheat (Triticum durum Desf.)
Abstract |
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Physiological tests as predictive appreciation for drought tolerance in durum wheat (Triticum durum Desf.)

R. Sayar¹*, H. Khemira², A. Kameli ³ and M. Mosbahi⁴

¹National Institute of Agriculture research of Tunisia (INRAT), Kef research station 7119Boulifa le Kef, Tunisia; email: sayarrhouma@yahoo.fr
²Science University of Gabès, Erriyad city, Zrig CP 6072, Tunisia;email: habibkhemira @ yahoo.com
³Department of Biology, High school, Vieux-Kouba, Alger, Algeria;email: abkameli@hotmail.com
⁴National Institute of Agriculture research of Tunisia (INRAT), Kef research station 7119Boulifa le Kef, Tunisia; email: inratkef.mosbahi@yahoo.fr
*Author to whom correspondence should be sent.• The name and address of the institution where the work was carried out: INRAT (AgricultureResearch National Iinstitute of Tunisia), Kef research station, Boulifa , 7119 Kef Tunisia.

Abstract:

Genetic advances in grain yield under rainfed conditions have been achieved by empirical breeding methods. Progress is slowed, however, by large genotype x season and genotype x location interactions arising from unpredictable rainfall, which is a feature of dry environments. A good understanding of factors limiting and/or regulating yield now provides us with an opportunity to identify and then select for physiological traits that increase drought tolerance and yield under rainfed conditions. Applying different physiological tests to appreciate drought tolerance in seedlings of durum wheat varieties leads to faster selection methods. Five (5) tests (germination, chlorophyll fluorescence extinction, electrolyte leakage, water and osmotic potential) were undertaken to evaluate the level of tolerance to water stress for 190 wheat accessions. Chlorophyll fluorescence extinction measurement seems to be the most reliable test enabling the discrimination of varieties according to their drought tolerance. Keywords: Drought tolerance evaluation, durum wheat and physiological tests

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91-99 P. Zeiger, A. Nurk, J. Lehtsaar and R. Värnik
Possibilities and contradictions in the calculation of the flat rate of the Value Added Tax Special Scheme for farmers in the European Union based on the Estonian example
Abstract |
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Possibilities and contradictions in the calculation of the flat rate of the Value Added Tax Special Scheme for farmers in the European Union based on the Estonian example

P. Zeiger¹, A. Nurk², J. Lehtsaar³ and R. Värnik⁴

¹Estonian University of Life Sciences Institute of Economics and Social Sciences,Kreutzwaldi 1, 51014 Tartu Estonia; e-mail: peedu.zeiger@emu.ee
²Her Majesty’s Treasury; Budget, Tax and Welfare Directorate; International IndirectTaxes Team, 1 Horse Guards Road, London SW1A 2HQ United Kingdom;e-mail: aili.nurk@hm-treasury.gsi.gov.uk
³Estonian University of Life Sciences Institute of Economics and Social Sciences,Kreutzwaldi 1, 51014 Tartu Estonia; e-mail: jyri.lehtsaar@emu.ee
⁴Estonian University of Life Sciences Institute of Economics and Social Sciences,Kreutzwaldi 1, 51014 Tartu Estonia; e-mail: rando.varnik@emu.ee

Abstract:

The current article deals with the application of the optional flat rate value added tax (hereinafter referred as VAT) scheme for farmers (VAT special scheme, special scheme, special flat-rate) in the member states of the European Union. In the flat rate VAT scheme, farmers are not registered as taxable persons liable for VAT; therefore it is not possible for the farmers to deduct the VAT paid on their inputs from the VAT payable on the supply of agricultural products. To compensate the VAT paid on inputs, the farmer adds the flat rate VAT to the taxable amount of his supply.The research results suggest that it is not currently justified to apply the special flat rateVAT scheme in Estonia. In the case of the continuation of subsidies payable to farmers it is necessary, based on the Estonian example, to make an amendment to the directive which would also allow the subsidies to be included in the amount of income in the calculations of the special flat rate. By applying the current provisions of the directive, the calculation of the special flat rate would result in a flat rate that would give rise to over-compensation in the agricultural business sector.

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101-108 K. Trükmann, E. Reintam, J. Kuht, E. Nugis and L. Edesi
Effect of soil compaction on growth of narrow–leafed lupine, oilseed rape and spring barley on sandy loam soil
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Effect of soil compaction on growth of narrow–leafed lupine, oilseed rape and spring barley on sandy loam soil

K. Trükmann¹, E. Reintam¹, J. Kuht¹, E. Nugis² and L. Edesi²

¹Estonian University of Life Sciences, Institute of Agricultural and Environmental Sciences,Kreutzwaldi St. 64, 51014 Tartu, Estonia; e-mail: katrin.trykmann@emu.ee
²Estonian Research Institute of Agriculture, Teaduse St. 13, 75501 Saku, Estonia

Abstract:

Soil compaction is an environmental problem and has been recognized as the main form of soil degradation in Europe. Soil compaction may increase soil strength and compacted soil layers can affect root and shoot growth. The aim of this work was to investigate the effect of soil compaction on soil properties and on the growth of narrow–leafed lupine (Lupinus angustifolius L.), spring oilseed rape (Brassica napus ssp. oleifera Hertzg.), and spring barley (Hordeum vulgare L.). The experiment was carried out on the research field of the Estonian University of Life Sciences in the summers of 2004 and 2005 on the sandy loam Stagnic Luvisol. The field was compacted by tractor MTZ-82 (total weight 4.84 Mg) characterized by multiple tire-to-tire passing. Parameters such as plants biomass (roots and shoots) and the changes in physical properties, bulk density and penetration resistance of soil were measured. The results of the present study revealed that the highest increase of penetration resistance and soil bulk density due to the soil compaction occurred in growing spring barley. Although the roots and shoots mass of lupine and oilseed rape increased with increased soil bulk density, there was a very strong negative linear correlation between the roots and shoots weight and soil bulk density on spring barley. A positive correlation was detected between the roots and shoots mass of narrow–leafed lupine and soil bulk density, and soil compaction had a positive effect on the roots and shoots mass of oilseed rape. The study indicates that oilseed rape and narrow–leafed lupine can grow more successfully on compacted soils than can barley.

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109-118 D. Valiūnas, M. Samuitienė, M. Navalinskienė and R. E. Davis
Identification of viral and phytoplasmal agents causing diseases in Gaillardia Foug. plants in Lithuania
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Identification of viral and phytoplasmal agents causing diseases in Gaillardia Foug. plants in Lithuania

D. Valiūnas¹, M. Samuitienė¹, M. Navalinskienė¹ and R. E. Davis²

¹Institute of Botany, Plant Virus Laboratory, Žaliųjų Ežerų 49, LT–08406, Vilnius, Lithuania;e-mail: deividas.valiunas@botanika.lt
²Molecular Plant Pathology Laboratory, USDA–Agricultural Research Service, Beltsville,MD 20705, USA

Abstract:

Gaillardia plants exhibiting symptoms characteristic of viral and phytoplasmal diseases were collected at botanical gardens and floriculture farms in Lithuania. Cucumber mosaic cucumovirus was isolated from diseased plants exhibiting symptoms characterized by stunting, flower breaking and malformation of petals. The virus was characterized based on electron microscopy, serology, reactions of inoculated test-plants, and reverse transcription polymerase chain reaction (RT–PCR). Symptoms of leaf yellowing and general stunting of plants, and virescence and phyllody of flowers were associated with infection by a phytoplasma. Phytoplasmal 16S rRNA gene sequences were amplified in polymerase chain reactions (PCRs) primed by phytoplasma universal primer pairs P1/P7 and R16F2n/R16R2. RFLP analysis of the 1.2 kbp rDNA product, subjected to single enzyme digestions with nine restriction endonucleases, revealed that the Gaillardia plants were infected by a phytoplasma (gaillardia yellows, GaiY) belonging to group 16SrI (aster yellows phytoplasma group), subgroup I–C (clover phyllody, CPh, phytoplasma subgroup). 16S rDNA sequence alignments and phylogenetic analysis confirmed that the GaiY phytoplasma was closely related to CPh phytoplasma. Gaillardia can be naturally infected by a broad biodiversity of phytoplasma strains belonging to subgroups 16SrIII–B (clover yellow edge subgroup), 16SrI–A (aster yellows subgroup), and 16SrI–C in Lithuania.

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121-129 Jacek Jaszczyński
Groundwater quality against a background of human activities and impact of peatland area
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Groundwater quality against a background of human activities and impact of peatland area

Jacek Jaszczyński¹

¹Experimental Station for Land Reclamation and Grassland Farming in Biebrza19-200 Grajewo, Poland, e-mail: j.jaszczynski@op.pl

Abstract:

The main objective of the study was an analysis of groundwater quality in a well on an extensive agricultural farm located near in the vicinity of peatlands. The influence of peatland and human activities on water quality was analysed. Thirty-six series of water samples were collected for the period from May 2000 to November 2005 from the well located at the farm and from wells located in the transect on the peatland area. In the collected water samples of pH and concentration of N-NO3, N-NH4, P, DOC, Na, K, Fe and Cl were determined. Meanvalues of N-NO3, K, Na and Cl concentrations in water from the farm well were higher thanconcentrations recorded in the control wells from the transect located on the peatland area. Higher N-NH4 and DOC concentrations were observed in water from the peatland. The resultsof these investigations showed that human activities on the farm area have a larger impact on groundwater quality than the peatland located near the farm.

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131-140 R. Oleszczuk and T. Brandyk
The analysis of shrinkage-swelling behaviour of peat-moorsh soil aggregates during drying-wetting cycles
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The analysis of shrinkage-swelling behaviour of peat-moorsh soil aggregates during drying-wetting cycles

R. Oleszczuk and T. Brandyk

Department of Environmental Improvement, Warsaw University of Life Sciences(SGGW), ul. Nowoursynowska 159, 02-776 Warsaw, Poland;e-mail:ryszard_oleszczuk@sggw.pl

Abstract:

The aim of this study was to investigate the soil volume changes for moorsh, willow and moss peat layers during drying-wetting cycles. The measurements of soil volume changes were made using the ‘saran resin’ method. The reversible and irreversible shrinkage coefficient values for each layer were calculated. The relationships between soil moisture contents before and after rewetting were estimated for analysed soil aggregates. The performed research showed that the soil volume changes were relatively small for moorsh and the highest for willow and moss peat. After a few drying-wetting cycles, the moorsh soil aggregates also retained the highest amount of water in comparison with willow and moss peat.

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141-148 R. Oleszczuk, T. Brandyk, T. Gnatowski, J. Szatyłowicz and J. Kamiński
The comparison of soil moisture content changes in the moorsh layer under shrubs and grass vegetation
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The comparison of soil moisture content changes in the moorsh layer under shrubs and grass vegetation

R. Oleszczuk¹, T. Brandyk¹, T. Gnatowski¹, J. Szatyłowicz¹ and J. Kamiński²

¹ Department of Environmental Improvement, Warsaw University of Life Sciences (SGGW), ul.Nowoursynowska 159, 02-776 Warsaw, Poland;e-mail: ryszard_oleszczuk@sggw.pl
² Institute for Land Reclamation and Grassland Farming,Biebrza Experimental Station, 19-200 Grajewo, Poland

Abstract:

The objective of the research was to compare the soil moisture content changes in the top moorsh layer (0–25 cm) covered by shrubs and grass vegetation under the same groundwater level and climatic conditions. The measurements of soil moisture content values for both sites under different vegetation were performed using the TDR method. The values of soil moisture content for shrubs ranged from 49.7% vol. to 14.4% vol. For grassland the values of moisture content ranged from 58.9% vol. to 24.9% vol. The analysis of soil moisture content values showed that it was lower by about 10% vol. under shrubs in comparison with grass vegetation under the same climatic and water table conditions.

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149-160 G. Sokolov L. Szajdak and I. Simakina
Changes in the structure of nitrogen-containing compounds of peat-, sapropel-, and brown coal-based organic fertilizers
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Changes in the structure of nitrogen-containing compounds of peat-, sapropel-, and brown coal-based organic fertilizers

G. Sokolov¹ L. Szajdak² and I. Simakina¹

¹Institute for Problems of Natural Resources Use and Ecology, National Academy of Sciencesof Belarus, Skarina str. 10, 220114 Minsk, Belarus; email: agrico@ns.ecology.ac.by
²Research Centre for Agricultural and Forest Environment of the Polish Academy of Sciences,ul. Bukowska 19, 60-809 Poznań; email: szajlech@man.poznan.pl.

Abstract:

The three-stage acidic hydrolysis method was used for the degradation of three organic fertilizers prepared on the basis of peat, sapropel and brown coal. This method of hydrolysis may simulate the processes that occur in the natural environment, influenced by chemical and biological factors with a high degree of reliability, by taking substances from fractions depending on stability of compounds in the investigated organic materials. The investigation of changes in the content of nitrogen in the studied fractions allows judging the character and the degree of transformation of nitrogen-containing compounds in kaustobioliths organic substances and prepared fertilizers. In these three organic fertilizers the content of readily (“easy”) hydrolysable nitrogen ranged from 49.1 to 58.4%, the content of hard-to- hydrolyse nitrogen ranged from 4.6 to 19.5%, in unhydrolysable rest, content ranged from 31.6 to 37%. The results showed a significant supply of nitrogen included in amino acid structures in soils. Amino acids represent a form of organic nitrogen, readily hydrolysable by chemicals and enzymes, available for plants and soil microorganisms. The highest supply was observed for the fertilizer prepared on the basis of brown coal. This fertilizer supplied 93.7 % more nitrogen than the reference soil. Two other fertilizers prepared on the basis of peat and sapropel supplied 64.1 % and 56.3 %, respectively more than reference soil. A relationship and good correlation were found between the contents of readily (“easy”) hydrolysable forms of nitrogen and the total amount of amino acids, and also between the contents of readily hydrolysable forms of nitrogen and concentrations of nitrogen in amino acid structures.

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