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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2016

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Sammendrag

Mixtures and pure stands of perennial ryegrass, tall fescue, white clover and red clover were grown in a three-cut and a five-cut system in southern Norway, at a low fertilization rate (100 kg N ha−1 year−1). The nutritional quality (annual weighted averages) of the dried forage from the two-first harvesting years was analysed. There was no significant effect of species diversity on crude protein (CP) concentration. In the three-cut system, we found a significant species diversity effect leading to 10% higher concentrations of acid detergent fibre (ADF), 20–22% lower concentrations of water-soluble carbohydrate (WSC) and 4% lower net energy for lactation (NEL) concentrations in mixtures compared with pure stands (averaged across the two-first years). In the five-cut system, similar effects were seen in the first year only. This diversity effect was associated with a reduction in WSC and NEL concentrations and an increase in ADF, NDF and CP concentrations in the grass species, and not in red clover, when grown in mixtures. This is thought to be a combined result of better N availability and more shading in the mixtures. Species diversity reduced the intra-annual variability in nutritional quality in both cutting systems.

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Sammendrag

1. Fire is a widespread management practice used in the maintenance of European heathland. Frequent prescribed burns in small patches have been shown to benefit carabid communities; however, how fire favours specific life-history traits is poorly understood. 2. In this study, we identify characteristic species of the successional stages within heathlands, and find the traits which are characteristic of species in burnt areas versus areas dominated by older heath stands. 3. We identify 10 species as indicator species for heathland in the pioneer stage (0–5 years old); Amara lunicollis, Bembidion lampros, Calathus fuscipes, Carabus problematicus, Cicindela campestris, Nebria salina, Notiophilus aquaticus, Poecilus cupreus, P. lepidus and P. versicolor. Dyschirius globosus is identified as an indicator for the building stage (6–14 years old), and Carabus violaceus as an indicator for the mature stage (15–25 years old). 4. Moisture preference and diet are identified as traits that determine species response to prescribed fire. Collembolan specialists and species with no moisture preference are shown to be most abundant in burnt patches, whereas generalist predators and species with a high moisture preference are less tolerant of fire. 5. Knowledge of species sorting along a prescribed fire gradient can provide valuable information for heathland conservation.