Vegetation and chemical plant and soil data from 18 terrestrial non-forested natural habitat types have been collected each year since 2004 (Table 1). Presently, cover data of plant species measured by pinpoint (16 grid points in 0.5 m x 0.5 m frame) and plant frequency data (5 m circles) exist for more than 50,000 plots; the measuring of chemical properties in plant, soil, and water samples has been less intense. Presently there are more than 12,000 registrations of carbon content and 57,000 measurements of pH in topsoil. Soils are always samples from the top 5 cm. On heathland habitats the thickness of the mor layer is measured. All data are georeferenced and can be accessed at http://www.naturdata.dk/ The data comprises approximately 1,200 sites both within and outside of Natura 2000 areas. At each site the measurements were made at 20-60 randomly positioned plots. 70% of the plots have been revisited each year, whereas 30 % have only been visited once. Each year a total number of additional 5,000 sample plots and registrations will be performed. The protocols for the different measurement types (in Danish) may be downloaded from http://www.dmu.dk/fileadmin/Attachments/TAN1_106_01_FDCNY1.pdf. This report describes the available content in the vegetation-plot database NATURDATA.DK (GIVD ID EU-DK-001).Keywords: moss; nitrogen; pin point; plant cover; plant frequency; soil analysis. GIVD Database ID: EU-DK-001Last

The competitiveness of two transgenic oilseed rape (Brassica napus ssp. napus) lines and their fertile transgenic hybrid was tested in field trials in Belgium and Denmark. The lines contained genes for male sterility, restoration of fertility and herbicide resistance. The competitiveness of the three transgenic lines was related to three non-transformed commercially-grown oilseed rape varieties: Drakkar, Topas and Line. As a reference of a more aggressive crucifer, white mustard (Sinapis alba) was also included in the experiment. The experimental design was a complete block design with two locations, monocultures and mixtures with barley (Hordeum vulgate), three plant densities, four harvest times and four blocks. The yield density relationship of the transgenic oilseed rape lines was not different from that of the non-transgenic varieties in either location. The first harvest times showed a vigorous biomass production of white mustard, which in turn produced a significant difference in the competitive ability between oilseed rape and white mustard. Later, this difference decreased, and in Belgium there was no difference at the last harvest time. Variations within populations may blur actual differences between lines and varieties, and it is argued that unless the experimental design covers a range of competitiveness for which it is possible to detect significant differences, test results reporting a lack of difference between transgenic and non-transgenic plants are of little value.

Questions How can conservation status of rich fen and alkaline spring areas be assessed most cost‐effectively based on existing monitoring data? What is the precision and accuracy of available indicators? Location Rich fen and alkaline spring areas in Denmark. Methods Potential indicators of conservation status were evaluated based on: accuracy, measured as the ability to predict the number of typical species in monitoring plots; precision, measured as variation over years of indicators in repeated plots; and cost of obtaining data for the indicator. Indicators were derived using data from the Danish National Monitoring and Assessment Programme for the Aquatic and Terrestrial Environment from 2000 to 2009. Indicators included biotic indices derived from species lists, abiotic measurements of pH and nutrients and structural measurements of vegetation height and tree cover. Results The majority of indicators showed a significant correlation with the number of typical species. Floristic indicators, especially based on Ellenberg nutrient values, showed superior correlation and were furthermore very stable over years. Structural indicators were generally accurate, but were highly imprecise with high between‐year variation. Among the abiotic indicators, pH and soil P were inaccurate, whereas tissue N content and nitrate in water were accurate but with low precision. When balancing efficiency of indicators with monitoring costs, laboratory analyses stand out as expensive compared to recording of a species list, the latter providing up to five valuable indicators. Conclusions Floristic indicators derived from Ellenberg values, and especially those related to nutrient availability, are cost‐effective indicators of conservation status. The method is applicable to all regions where Ellenberg indicator values have been calibrated to fit local conditions.

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