Tag Archives: farming system

191-197 L. Balezentiene and E. Klimas
Effect of organic and mineral fertilizers and land management on soil enzyme activities
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Effect of organic and mineral fertilizers and land management on soil enzyme activities

L. Balezentiene and E. Klimas

Lithuanian University of Agriculture, Studentų 11, Akademija LT– 53361, Kaunas distr.;e–mail: ligita.balezentiene@lzuu.lt

Abstract:

Sustainable and rational management of agrophytocenoses depends on various bio-indices and methods of application, particularly the development and protection of soil resources (Lai et al., 2002). Among other indices, enzyme activity is proposed as a universal index of soil fertility and contamination (Dilly et al., 2003). To ascertain and to make a comparison of bioactivity variation during the vegetation period, soil (Endophypogleyi-Eutric Planasols-Ple-gln-w, artificial drainage) samples were collected from rotation fields of different fertilizing and farming systems (intensive (IF) and organic (OF)) at the Training farm of the Lithuanian University of Agriculture during 2007–2008. N application stimulated urease and saccharase activity in different farming systems (OF and IF) and fertilizing management (manure and mineral fertilizers). When comparing mean soil bioactivity values of 2 years the highest manure effect was detected in the application year (winter wheat treatment) and conditioned the highest urease (8.21 mg NH +–4N g-1) and saccharase (24.52 mg CG g-1 24 h-1)activity but gradually decreased later. The lowest mean of urease (3.62 mg NH +–4N g-1) andsaccharase (22.07 mg CG g-1 24 h-1) activity occurred in IF soil where mineral fertilizers were applied. Soil bioactivity properties (urease and saccharase activity) were positively correlated with soil nutrients (Corg., Ntotal). Urease and saccharase activity properties reflect changes of fertilizer type and management and thus can be used as bio-indicators of soil fertility.

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662-667 D. Matt, E. Veromann and A. Luik
Effect of housing systems on biochemical composition of chicken eggs
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Effect of housing systems on biochemical composition of chicken eggs

D. Matt, E. Veromann and A. Luik

Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences,Kreutzwaldi 1, EE51014 Tartu, Estonia; tel: +372 7425 010; e-mail: darja.matt@emu.ee

Abstract:

The aim of this study was to investigate the impact of production system (organic, conventional) on the quality of chicken eggs. Energetic value, carbohydrate, cholesterol, protein, fatty acid, sodium, potassium, phosphorus, dry matter and vitamin contents were evaluated. The mean content of cholesterol was 30%, and potassium 7%, greater in the organic eggs compared with the conventional eggs. No significant difference was found in the content of fatty acids, protein, sodium or dry matter. The organic eggs had considerably lower contents of calcium (2.8 times) compared with eggs from conventional farming. Negligible differences were found in the occurrence of vitamins (vitamin A, vitamin E, vitamin D3). The residues of 45 pesticides and 6 PCB isomers were analyzed in both types of eggs and no residues compounds were found.

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531-542 T. Meysner, L. Szajdak and J. Kuś
Impact of the farming systems on the content of biologically active substances and the forms of nitrogen in the soils
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Impact of the farming systems on the content of biologically active substances and the forms of nitrogen in the soils

T. Meysner¹, L. Szajdak¹ and J. Kuś²

¹Research Center for Agricultural and Forest Environment, Polish Academy of Sciences,Bukowska 19, 60-809 Poznań, Poland; e-mail: szajlech@man.poznan.pl
²Institute of Soil Science and Plant Cultivation, Czartoryskich 8, 24-100 Puławy, Poland;e-mail: jankus@iung.pulawy.pl

Abstract:

Investigations were carried out in 2000 and 2001 to assess the impact of four farming systems on the content of biologically active substances and different forms of nitrogen in the soils. The transformation of bound amino acids and the total amount of free phenolic acids, urease activity as well as the total nitrogen, concentration of ammonium, nitrate, organic carbon, and humus in the soils were related to the choice of the farming systems. The highest concentration of bound amino acids, lysine and β–alanine, the total nitrogen, organic carbon, and humus in soils was found in ecological and conventional systems. It was confirmed that the increase of free phenolic acids in the soils of continuous cropping of winter wheat was followed by the decrease of the yearly mean concentrations of urease activity, the total amount of bound amino acids, the total nitrogen and grain yields, weight of 1000 grains, and number of ears m-2. The conventional system affects the increase of the yearly mean concentrations of the total amount of bound amino acids, the ammonium ions, and the grain yield, weight of 1000 grains, number of ears m-2 and the decrease of the total amount of free phenolic acids in the soils.

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