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Ecological agriculture- a way towards sustainable agricultural practice Organic Eprints
Znaor, Darko; Bošnjaković, Branko.
Today, and especially in the years to come, agriculture, as well as all other human activities, will have to pay much more attention to their environmental impacts. In other words, it is expected that in the near future only technologies which care about environmental aspects will be promoted and accepted by policy makers, scientists, consumers, and society in general. This is not surprising since the environmental problems are among the most urgent ones our civilization will have to tackle and solve. This demand for more careful stewardship of environment is also acknowledged by philosophy of sustainable development - a widely recognized concept and necessity of future development. Although established at the very beginning of this century, ecological...
Tipo: Journal paper Palavras-chave: "Organics" in general; Farming Systems; Nutrient turnover; Social aspects; Air and water emissions; Soil; Biodiversity and ecosystem services; Food systems; Policy environments and social economy; Environmental aspects.
Ano: 1996
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Stickstoffeffizienz von unterschiedlich aufbereiteten Misten in einer Ackerbaufruchtfolge auf Lösslehm Organic Eprints
Berner, Alfred; Scherrer, Daniel; Alföldi, Thomas.
Schlussfolgerungen Unter der Einschränkung, dass die alleinige Betrachtung der N-Wirkung nur einen Teil des N-Haushaltes ausmacht (z.B. Einbau von N in den Humuskörper), können aus den vorliegenden Ergebnissen folgende Schlussfolgerungen gezogen werden: • Bei der aeroben Rotte bzw. Kompostierung von Mist wurden im Vergleich zur anaeroben Lagerung von Mist grössere N-Verluste gemessen, d.h. es wurde bei diesen Verfahren folglich weniger Stickstoff auf die Parzellen ausgebracht. • Bei der Anwendung auf dem Feld erzielten Rottemist und Mistkompost im Vergleich zu Stapelmist jedoch eine bessere N-Wirkung. Dies macht deutlich, dass bei der Beurteilung unterschiedlicher Mistformen neben N-Verlusten und N-Gehalten insbesondere die N-Wirkung...
Tipo: Book chapter Palavras-chave: Composting and manuring; Nutrient turnover; Soil quality; Soil biology.
Ano: 1997 URL: http://orgprints.org/2909/1/berner%2Det%2Dal%2D1997%2Dstickstoffeffizienz.pdf
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Changes in the nutrient content of agricultural soil on conversion to organic farming, in relation to farm level nutrient balances and soil contents of clay and organic matter. Organic Eprints
Løes, Anne-Kristin; Øgaard, Anne Falk.
Agricultural soil on 12 farms converting to organic farming was sampled in 1989 and 1995 at the same sample points. Concentrations of plant-available (-AL) P, K, Ca and Mg, HNO3-soluble K, tot- N, tot-C and pH were measured in two layers. The average K-AL concentration and pH were reduced in both layers. The average P-AL concentration was reduced in the topsoil. K-AL and P-AL increased in samples with low concentrations and decreased in samples with high and very high concentrations in 1989. The total N concentration increased in the subsoil. Tot-N and tot-C increased in top- and subsoil with a low organic matter content. The net import of P, calculated by farm level nutrient balances, was negatively correlated to the change in kg P-AL per hectare in the...
Tipo: Journal paper Palavras-chave: Nutrient turnover; Farm nutrient management.
Ano: 1997 URL: http://orgprints.org/5945/1/Acta_1997%2C_Changes_in_the_nutrient_content...pdf
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A comparative study of nitrate leaching from intensively managed monoculture grass and grass-clover pastures Organic Eprints
P.S., Hooda; M., Moynagh; I.F., Svoboda; H.A., Anderson.
Nitrate leaching losses from intensively managed monoculture grass and grass-clover pastures were measured during 1994-96 at a long-term experimental farm in south-west Scotland. Field-size lysimeter plots were established in 1993 on the existing pastures on a silty clay loam non-calcareous gley. No fertilizer-N was applied to the grass-clover, while the monoculture grass was fertilized with c.240 kg N ha-1 year-1, but both swards received 2-3 cattle slurry applications annually (120-390 kg total N ha-1 year-1). The pastures supported 2-3 cuts for silage conservation, and were grazed by dairy cattle and stocked with sheep during the winter months. Initially, leachate nitrate concentrations from the fertilized grass were considerably larger than those...
Tipo: Journal paper Palavras-chave: Nutrient turnover; Farm nutrient management.
Ano: 1998 URL: http://orgprints.org/6175/1/Younie2002Effect.pdf
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Variations in the natural abundance of 15N in ryegrass/white clover shoot material as influenced by cattle grazing. Organic Eprints
Eriksen, Jørgen; Høgh-Jensen, Henning.
Biological N2 fixation in clover is an important source of N in low external-N input farming systems. Using the natural 15N-abundance method, variations in N2 fixation were investigated in grazed and mowed plots of a ryegrass/white clover field. Ryegrass 15N varied considerably, from 0.2 to 5.6‰ under mowed conditions and from -3.3 to 11.6‰ under grazed conditions. Variations in 15N in white clover were lower than in ryegrass, especially in the mowed plots (SE = 0.05‰, n = 20). The variations in the percentage of nitrogen derived from the atmosphere (%Ndfa) in white clover were highest in the grazed plots where it ranged from 12 to 96% (mean = 64%) compared with the mowed plots where it ranged from 64 to 92% (mean = 79%). Thus, the N2 fixation per unit...
Tipo: Journal paper Palavras-chave: Nutrient turnover.
Ano: 1998 URL: http://orgprints.org/139/1/PLSO7762.doc
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Organic Arable Systems at ADAS Terrington OF0112 Organic Eprints
Cormack, Dr W F.
Project OF0112 contributes to MAFF's main policy focus of encouraging conversion to organic farming methods. It is part of a long term rotational study that began in 1990 as OF0102 and has recently been extended to 2001 as OF0145. The overall objective of these three projects is to evaluate the cost of conversion to organic arable production on a fertile soil, to assess the physical and financial performance of the organic rotation, to identify and overcome limitations to sustainabilty and to compare the results with conventional arable production. The project comprises a field-scale unreplicated systems comparison and associated replicated experiments at ADAS Terrington, and a financial analysis of ten commercial 'linked' organic farms. The silty...
Tipo: Report Palavras-chave: Nutrient turnover; Production systems; Farm nutrient management.
Ano: 1998 URL: http://orgprints.org/9929/1/organic_arable_systems_at_adas_terrington_of0112.pdf
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Nährstoffversorgung im Biogemüsebau Organic Eprints
Lichtenhahn, Martin; Berner, Alfred; Van der Berge, Paul.
Das Merkblatt beschreibt neben den Grundsätzen der Nährstoffversorgung Potenzial und Einsatzmöglichkeiten der wichtigsten Nährstoffquellen und zeigt den Einfluss von Kulturmassnahmen auf. Ein Leitfaden zur Berechnung von Düngergaben rundet die Broschüre ab.Die gedruckte Version des Merkblattes ist derzeit vergriffen.
Tipo: Book Palavras-chave: Nutrient turnover; Vegetables.
Ano: 1998 URL: http://orgprints.org/25419/1/1082-naehrstoffe.pdf
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Turnover of organic matter in differently textured soils: II. Microbial activity as influenced by soil water regimes Organic Eprints
Thomsen, I.K.; Schjønning, P.; Jensen, B.; Kristensen, K.; Christensen, B.T..
To evaluate the effect of soil texture and soil water content on decomposition of organic carbon (OC), turnover of partially stabilized 14C-labelled ryegrass residues was studied at four matric potentials in twelve differently textured soils of similar origin and cropping history. Six soils were from a naturally occurring clay gradient and had 11, 16, 21, 31, 37 and 45% clay (termed NA1 to NA6). Three clay-amended soils (CL2, CL4, CL6) and three silt-amended soils (SI2, SI4, SI6) were prepared by adding clay or silt sized organomineral complexes extracted from the NA2 soil to a portion of the NA1 soil. After 14C-labelled ryegrass had decomposed for eight months under field-like conditions, soil cores were sampled, adjusted to four matric potentials (-30,...
Tipo: Journal paper Palavras-chave: Nutrient turnover; Soil quality; Soil biology.
Ano: 1999 URL: http://orgprints.org/727/1/geoderma_99_II.pdf
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Turnover of organic matter in differently textured soils. I. Physical characteristics of structurally disturbed and intact soils Organic Eprints
Schjønning, P.; Thomsen, I.K.; Møberg, J.P.; de Jonge, H.; Kristensen, K.; B.T., Christensen.
Soil type effects on organic matter turnover are most often ascribed directly to differences in soil clay content. Since soil texture determines the physical characteristics of soil, aggregation and water holding capacity may be more relevant to address in the search for controls of organic matter turnover. Most studies of microbial processes in soils are based on structurally disturbed soil, where the abiotic conditions for the microbial activity may be quite different from those in intact soils. In this study, basic physical characteristics were determined for structurally disturbed and intact soil samples from differently textured soils. Bulk soil was retrieved from 0–20 cm depth at six locations along a textural gradient in an arable field on...
Tipo: Journal paper Palavras-chave: Nutrient turnover; Soil quality; Soil biology.
Ano: 1999 URL: http://orgprints.org/726/1/geoderma_99_I.pdf
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Soil sulphur status following long-term annual application of animal manure and mineral fertilizers. Organic Eprints
Eriksen, Jørgen; Mortensen, Jørgen.
In agricultural systems with low S inputs, crops rely on the release of S from organic forms in the soil. In the Askov long-term experiments, started in 1894 on both sandy and loamy soils, was investigated the soil S status following long-term application of animal manure and mineral fertilizers in the growing season of 1995. In a field trial with oil-seed rape (Brassica napus, L.) soil analysis, leaf tissue analysis, yield and S-removal in plant material was used to characterize differences in availability of soil S. One half of all plots had 63 kg S/ha as gypsum applied. Fertilization with animal manure or NPK fertilizer increased the content of soil organic C compared with unfertilized plots. This increase was followed by a similar build-up of organic...
Tipo: Journal paper Palavras-chave: Nutrient turnover.
Ano: 1999 URL: http://orgprints.org/141/1/TEKST.doc
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Nährstoffbilanzen im biologischen Landbau Organic Eprints
Berner, Alfred; Heller, Stefan; Mäder, Paul.
Mit Nährstoffbilanzberechnungen lassen sich Umweltleistungen im Bereich des Nährstoffeinsatzes in der Landwirtschaft aufzeigen. In der Schweiz ist die Erfüllung einer ausgeglichenen Bilanz Voraussetzung für staatliche Subventionen im Rahmen von Ökoprogrammen. Auf den Biobetrieben wird zur Nährstoffbilanzberechnung seit langem die sogenannte DGVE-Methode (Gemüsebau: LBL-Methode), auf integriert produzierenden Betrieben die sogenannte LBL-Methode eingesetzt (Tab.1). Von der staatlichen Biokontrolle wurde zunehmend eine einheitliche, für alle Betriebstypen einsetzbare Methode verlangt. Anhand von Praxisdaten sollten daher die oben genannten Methoden auf ihre Vergleichbarkeit überprüft werden. Um die Salden besser bewerten zu können, wurden sie mit den in...
Tipo: Book chapter Palavras-chave: Composting and manuring; Nutrient turnover; Soil quality; Soil biology.
Ano: 1999 URL: http://orgprints.org/2908/1/berner%2Det%2Dal%2D1999%2Dnaehrstoffbilanzen.pdf
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Lichtangebot und Bodentemperatur in Winterroggen unterschiedlicher Bestandesdichte und deren Konsequenzen für die Stickstoffmineralisation Organic Eprints
Raupp, Dr Joachim.
According to literature reports farmyard manure application caused higher amounts of microbial activity in soils compared to mineral fertilizers. If lab tests have been carried out (e.g. enzyme activity, microbial biomass) results can be attributed to soil properties, as experimental conditions have been constant. With plots of a long-term field trial it has been studied whether organic or mineral fertilization has any effect on soil temperature (depending on different crop density in each treatment) and, by this way, also on N mineralization. Soil temperature was higher in organically than in minerally fertilized winter rye, but only on sunny days, not on cloudy ones. Differences have been measured to a soil depth of 15 cm. However, N mineralization did...
Tipo: Conference paper, poster, etc. Palavras-chave: Nutrient turnover; Soil biology.
Ano: 1999 URL: http://orgprints.org/757/1/rawitabe.pdf
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Växtnäringens flöde genom jordbruk och samhälle – vägar att sluta kretsloppen Organic Eprints
Granstedt, Artur.
I dag går större delen av den växtnäring som tillförs jordbruket förlorat till luft och vatten eller binds i marken. Detta innebär en kostnad för jordbruket och leder samtidigt till skador på den omgivande miljön. Jordbruket bedöms svara för över 40 procent av kväveläckaget till Östersjön. Kväveförlusterna till luften i form av ammoniak bidrar också till övergödningen och det sura nedfallet. Målsättningen att halvera kväveförlusterna från jordbruket har inte uppnåtts. Trots att det är endast en liten del av fosforöverskottet i jordbruket som läcker ut i vattendragen har även detta skadliga konsekvenser för miljön i form av övergödning av sjöar, vattendrag och hav. I föreliggande studie beskrivs växtnäringsflödena i jordbruket och orsakerna till dagens...
Tipo: Report Palavras-chave: Nutrient turnover.
Ano: 1999 URL: http://orgprints.org/298/1/ekolantbr29.pdf
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Nitrate leaching in an organic dairy/crop rotation as affected by organic manure type, livestock density and crop. Organic Eprints
Eriksen, J; Askegaard, M; Kristensen, K.
In dairy farming systems the risk of nitrate leaching is increased by mixed rotations (pasture/arable) and the use of organic manure. We investigated the effect of four organic farming systems with different livestock densities and different types of organic manure on crop yields, nitrate leaching and N balance in an organic dairy/crop rotation (barley – grass-clover – grass-clover – barley/pea – winter wheat – fodder beet) from 1994 until 1998. Nitrate concentrations in soil water extracted by ceramic suction cups ranged from below 1 mg NO3-N/l in 1st year grass-clover to 20-50 mg NO3-N/l in the winter following barley/pea and winter wheat. Peaks of high nitrate concentrations were observed in 2nd year grass-clover, probably due to urination by grazing...
Tipo: Journal paper Palavras-chave: Nutrient turnover.
Ano: 1999 URL: http://orgprints.org/142/1/Text.doc
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Symbiotic nitrogen fixation and N-transfer in a grass-white clover mixture Organic Eprints
Vinther, Finn P..
Symbiotic N2 fixation (SNF) and transfer of fixed N from clover to grass in a grass-white clover mixture was measured during two years using 15N isotope dilution techniques. White clover derived from 87 to 99% of its N from the atmosphere. The total SNF ranged from 150 to 277 kg N ha-1 yr-1, which corresponded to 34-45 mg N fixed per gram of white clover dry weight. The transfer of fixed N from clover to grass corresponded to approximately 10 kg N ha-1 yr-1.
Tipo: Journal paper Palavras-chave: Nutrient turnover; Soil quality; Soil biology; Pasture and forage crops.
Ano: 2000 URL: http://orgprints.org/178/1/FPV415_N%2Dfix_Aalborg_2000.pdf
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Nitrate leaching following cultivation of contrasting temporary grassland. Organic Eprints
Eriksen, J.; Søegaard, K..
The N-surplus in grazed grassland is much higher than in cut grassland. Therefore, the residual effects of three years of temporary grassland on nitrate leaching in the following cereal crop were determined. Grassland managements were either cut leys or grazing with dairy cows in both pure grass and grass-clover mixtures. The cows were fed two levels of N in the supplements. Grassland management had little effect on the subsequent nitrate leaching, which ranged from 6 to 36 kg N ha-1, even though the surplus after three years of grassland ranged from 36 to 984 kg N ha-1. This indicates that substantial losses occurred during the grassland period. Application of fertiliser-N to the cereals had a much larger effect on nitrate leaching. It is concluded that...
Tipo: Journal paper Palavras-chave: Nutrient turnover.
Ano: 2000 URL: http://orgprints.org/149/1/437.ppt
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Sulphate leaching in an organic crop rotation on sandy soil in Denmark. Organic Eprints
Eriksen, J; Askegaard, M.
Sulphate leaching losses may reduce the long-term possibility of maintaining the S supply of crops in low input farming systems. Sulphate leaching and S balances were investigated in an organic dairy/crop rotation (barley [Hordeum vulgare]  grass-clover [Lolium perenne/Trifolium repens]  grass-clover  barley/pea [Pisum arvénse]  winter wheat [Tritucum aestivum]  fodder beet [Beta vulgaris]) from 1994 until 1998. The importance of climatic conditions and use of different organic manure types at different application rates for sulphate leaching were investigated and related to the concurrent nitrate leaching. As an average of years, sulphate leaching from the crop rotation was 20 kg S ha-1, which was equivalent to 60% of the total input to the rotation....
Tipo: Journal paper Palavras-chave: Nutrient turnover.
Ano: 2000 URL: http://orgprints.org/144/1/text.doc
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Soil Stresses, Quality and Care Organic Eprints
Elmholt, Susanne; Stenberg, Bo; Grønlund, Arne; nuutinen, Visa.
NJF-seminar Soil Stresses, Quality and Care Different people understand differently the word soil. The soil can be looked upon as a body of nature and a part of the landscape. To many people soil is the substrate for plant growth and a prerequisite for food production and wealth. A third and perhaps growingly important view is soil as the physical ground for housings, roads and industry. Soil is important to the whole society, not only for the agricultural sector. Soil has important ecological functions as it interacts with the dead bedrock, the atmosphere, the water, and the living organisms. Important functions are: Biomass producer and transformer Geomembrane, filter and buffer Habitat for living organisms Raw material and building ground...
Tipo: Proceedings Palavras-chave: Production systems; Research methodology and philosophy; Farming Systems; Composting and manuring; Nutrient turnover; Soil quality; Soil tillage; Soil biology.
Ano: 2000 URL: http://orgprints.org/979/1/MailsamletDJFSE_rettet_Per_Bo.pdf
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Bio fördert Bodenfruchtbarkeit und Artenvielfalt - Erkenntnisse aus 21 Jahren DOK-Versuch Organic Eprints
Fliessbach, Andreas; Mäder, Paul; Pfiffner, Lukas; Dubois, David; Gunst, Lucie.
In leicht verständlicher Sprache fasst das Dossier die eindrücklichen Ergebnisse aus dem DOK-Langzeitversuch zusammen, in dem die biologisch-dynamische mit der organisch-biologischen und der konventionellen Anbaumethode verglichen werden. Ausgewertet und kommentiert werden die Erträge, Nährstoffzufuhr und -entzug, Bodenstruktur, Bodenleben und Artenvielfalt.
Tipo: Book Palavras-chave: Nutrient turnover; Soil biology; Biodiversity and ecosystem services; Soil quality.
Ano: 2000 URL: http://orgprints.org/2913/1/1089-dok.pdf
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Symbiotic nitrogen fixation and N-transfer in a grass-white clover mixture Organic Eprints
Vinther, Finn P..
Symbiotic N2 fixation (SNF) and transfer of fixed N from clover to grass in a grass-white clover mixture was measured during two years using 15N isotope dilution techniques. White clover derived from 87 to 99% of its N from the atmosphere. The total SNF ranged from 150 to 277 kg N ha-1 yr-1, which corresponded to 34-45 mg N fixed per gram of white clover dry weight. The transfer of fixed N from clover to grass corresponded to approximately 10 kg N ha-1 yr-1.
Tipo: Conference paper, poster, etc. Palavras-chave: Nutrient turnover; Soil quality; Soil biology; Pasture and forage crops.
Ano: 2000 URL: http://orgprints.org/180/1/N%2Dfix_poster_Aalborg_2000.pdf
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