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| Ejrnæs, Rasmus; Liira, Jaan; Poulsen, Roar S.. |
| This study deals with the succession from abandoned fields to semi-natural grassland and heathland vegetation and the discrimination between these types of habitat. We hypothesise that semi-natural condition may be indicated by species lists of vascular plants. A statistical classification model is developed, based on 2059 reference samples from Danish ancient grasslands and heathlands, and abandoned fields of varying age. This Succession Model is shown to discriminate effectively between abandoned fields and semi-natural habitats, and it is suggested to be useful for the detection of conservation-worthy abandoned fields. A test of four hypotheses regarding the model prediction of naturalness of abandoned fields revealed that successional age, period of... |
| Tipo: Journal paper |
Palavras-chave: Biodiversity and ecosystem services. |
| Ano: 2003 |
URL: http://orgprints.org/10276/1/10276.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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| Aude, Erik; Ejrnæs, Rasmus. |
| A three-year multi-factorial microcosms experiment simulating dry grassland was used to test five hypotheses concerning establishment and persistence of bryophytes in grassland vegetation. The experimental treatments included fertilisation, defoliation and species composition of vascular vegetation. ANOVA-modelling showed a significant response of bryophyte species richness to fertilisation (negative) and defoliation (positive). Species composition of vascular vegetation had no effect on bryophyte richness, but a significant negative relationship was found between vascular plant biomass and species richness of bryophytes. Vascular plant dry weight above 400 g m-2 appeared fatal to bryophytes. At high nutrient levels, bryophytes extinction seemed to be... |
| Tipo: Journal paper |
Palavras-chave: Biodiversity and ecosystem services. |
| Ano: 2003 |
URL: http://orgprints.org/1293/1/Bryophyte_colonisation.pdf |
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