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| Registros recuperados: 15 | |
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| Fredshavn, Jesper; Tybirk, Knud; et al.,. |
| The work is organised in five work packages (WP 1-5, Table A1). Since the start in July 2001 the following work has been accomplished: WP 1. Starting up seminar and the annual seminars have served as a successful platform for project planning and cross-cutting activities. The general project co-ordination and planning of field work and selection of case study areas has been stimulated both at these meetings and in separate meetings with the WP responsibles. The first cross-cutting (CC4) has been accomplished in close co-operation with WP 5 and all project scientists. A homepage for the project is now available. WP 2. Eleven case areas with high concentration of organic farmers have been selected and 347 farmers have been interviewed. A database... |
| Tipo: Report |
Palavras-chave: Nutrient turnover; Landscape and recreation; Soil biology; Biodiversity and ecosystem services. |
| Ano: 2003 |
URL: http://orgprints.org/1577/1/1577.pdf |
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| Bruus, Marianne; Axelsen, Jørgen Aagaard; Tybirk, Knud. |
| Generally, it is expected to find food webs and food chains in all ecosystems, also highly disturbed ones such as agricultural fields. However, in a preliminary study in Danish conventionally managed fields it was not possible to identify food web nodes between weeds and herbivores, and it was hypothesized that the weed density in conventionally managed Danish agricultural fields were too low to support a more or less specialised herbivorous arthropod fauna. This hypothesis was investigated through an analysis of data on weeds and arthropods from conventionally and organically managed fields in Denmark. Sampling of arthropods was done by aid of D-vac and the sampling of weeds and crop was done at exactly the same site within two days. Most weeds and some... |
| Tipo: Journal paper |
Palavras-chave: Biodiversity and ecosystem services. |
| Ano: 2013 |
URL: http://orgprints.org/23252/2/23252.pdf |
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| Tybirk, Knud; Aude, Erik; Pedersen, Marianne Bruus. |
| Many attempts have been suggested to reduce the impact of modern conventional farming on the environment and semi-natural ecosystems. One of the attempts has been to introduce organic farming, which is known primarily for the absence of pesticides and artificial fertilising. The objective of this paper is to present differences found in the spontaneous vegetation and associated arthropods of comparable hedgerows situated within organic and conventional farming systems. We found significantly more plant and moss species in organic hedges, both in the individual plots, the individual hedges and when comparing the farming systems. Six species (Brachythecium rutabulum, Cerastium fontanum, Ranunculus repens, Cirsium arvense, Sonchus arvensis, Plantago... |
| Tipo: Report chapter |
Palavras-chave: Biodiversity and ecosystem services. |
| Ano: 2003 |
URL: http://orgprints.org/10371/1/10371.pdf |
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| Aude, Erik; Tybirk, Knud; Pedersen, Marianne Bruus. |
| Many attempts have been made to reduce the impact of modern conventional farming on the environment and semi-natural ecosystems. One of them is organic farming, known primarily for the absence of pesticides and artificial fertilisers. The objective of this study was to study and test the differences in the spontaneous vegetation of comparable hedgerows in the same area situated within organic and conventional farming systems. The hedge bottom vegetation was surveyed during August 2001 in 13 hedgerows of each farming system. Farming type had not changed on either side of the hedgerows for the lifetime of the hedges (10-14 years). Sampling was associated with a set of 16 measured environmental variables. In the two farming systems hedgerows were comparable... |
| Tipo: Journal paper |
Palavras-chave: Biodiversity and ecosystem services. |
| Ano: 2003 |
URL: http://orgprints.org/1425/1/agee_213.pdf |
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| Bruus, Marianne; Axelsen, Jørgen Aagaard; Tybirk, Knud. |
| Weeds are important as food for both herbivorous insects and farmland birds. Especially monophagous, herbivorous insects depend on the presence of one or a few weed species, and consequently a shortage of such weed species may hamper parts of the food web of the agricultural ecosystem. In any ecosystem on the earth food webs and food chains are expected, i.e. that there are species from one trophic level feeding on the lower trophic levels. These levels may be organised as organic matter – degrader, plant – herbivore and predator – prey, where preys may be degraders, herbivores and other predators. In describing ecosystems the trophic connections are often described as nodes linking species from one trophic level to another, and in most ecosystems it is... |
| Tipo: Journal paper |
Palavras-chave: Biodiversity and ecosystem services. |
| Ano: 2013 |
URL: http://orgprints.org/23251/3/23251.pdf |
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| Aude, Erik; Tybirk, Knud; Michelsen, Anders; Ejrnæs, Rasmus; Hald, Anna Bodil; Mark, Susanne. |
| The aim was to compare and test differences in the conservation value of hedge bottom vegetation on organic and conventional farms. The studied hedgerows (28 organic and 28 conventional) were on average 14 years old and established in the same way, except that organic hedgerows were established and managed without use of pesticides. We investigated three sample plots of 10 m2 in all hedgerows together with a set of 13 explanatory variables. There were no differences in soil texture between hedgerow types but organic farms had higher pH and lower conductivity. Organic farms had higher total N values, which are explained by a slightly higher content of organic matter. There was highly significant interaction between farming type and neighbouring crop type... |
| Tipo: Journal paper |
Palavras-chave: Biodiversity and ecosystem services. |
| Ano: 2004 |
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| Bruus Pedersen, M.; Axelsen, Jørgen Aagaard; Tybirk, Knud. |
| Correlations between the weed flora and the arthropod fauna of conventionally and organically managed fields were analysed. The results indicate that the abundance of weeds in Danish conventionally grown cereal fields is too low to sustain a population of more or less species specific herbivores, i.e. too low to maintain functioning food chain links between weeds and herbivores. Organically grown fields with a higher abundance of weeds may be capable of sustaining a fauna of arthropods relying on the weeds. The data from extra- weedy areas support this hypothesis, indicating that particularly weed-rich fields can better support herbivorous insects. |
| Tipo: Journal paper |
Palavras-chave: Biodiversity and ecosystem services. |
| Ano: 2011 |
URL: http://orgprints.org/19041/6/19041.pdf |
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| Tybirk, Knud; Fredshavn, Jesper. |
| This paper presents shortly an ongoing project on the influence of organic farming on nature quality in a broad sense. This includes investigations of patterns of localisation of organic farming in relation to landscapes, biological diversity outside organic fields, ecosystem diversity and function of fields and landscapes in organic farming as well as perceptions and practices of organic farming. The aim of the project is to identify key components to ensure continuous development of organic farming towards a closer integration of nature quality with food production. Some preliminary botanical data are presented showing that nature on organic farms is dominated by very common competitive species also dominating uncultivated biotopes in conventional farming. |
| Tipo: Conference paper, poster, etc. |
Palavras-chave: Landscape and recreation; Biodiversity and ecosystem services. |
| Ano: 2003 |
URL: http://orgprints.org/1236/1/nkoej_plantevaernskonf.pdf |
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| Pedersen, Marianne Bruus; Aude, Erik; Tybirk, Knud. |
| The aim of the project was to compare flora and insect fauna of organic and conventional hedgerows and to study whether the drift of herbicides into hedgerows alone or in combination with differences in fertiliser application may explain any differences. The project consequently consisted of two parts, viz. collection of flora and insect data in existing hedgerows (multi-row hedgerows, age 10-15 years) on two soil types and an experiment in which a sown grassland vegetation was treated with combinations of glyphosate (0-25% label rate) and nitrogen (0-100 kg N/ha/year) as a simulation of the most important agricultural conditions having an effect on flora and insect fauna in different agricultural systems. In the experiment flora and insect fauna were... |
| Tipo: Report chapter |
Palavras-chave: Biodiversity and ecosystem services. |
| Ano: 2004 |
URL: http://orgprints.org/10372/1/10372.pdf |
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| Registros recuperados: 15 | |
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