Stormwater runoff contains a broad range of micropollutants. In Europe a number of these substances are regulated through the Water Framework Directive, which establishes Environmental Quality Standards (EQSs) for surface waters. Knowledge about discharge of these substances through stormwater runoff and combined sewer overflows (CSOs) is essential to ensure compliance with the EQSs. Results from a screening campaign including more than 50 substances at four stormwater discharge locations and one CSO in Copenhagen are reported here. Heavy metal concentrations were detected at levels similar to earlier findings, e.g., with copper found at concentrations up to 13 times greater than the Danish standard for surface waters. The concentration of polyaromatic hydrocarbons (PAHs) exceeded the EQSs by factors up to 500 times for stormwater and 2,000 times for the CSO. Glyphosate was found in all samples whilst diuron, isoproturon, terbutylazine and MCPA were found only in some of the samples. Diethylhexylphthalate (DEHP) was also found at all five locations in concentrations exceeding the EQS. The results give a valuable background for designing further monitoring programmes focusing on the chemical status of surface waters in urban areas.

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J. 1993. Recolonization of experimentally bared soil in a grazed common in Denmark. -Nord. J. Bot. 13: 431440. Copenhagen. ISSN 0107455X.In an old grazed and very diverse common in Central Zealand, Denmark, the recolonization of vegetation on experimentally bared mineral soil was studied over a six years period (198691). In six experimental squares (1 X 1 m) in pairs placed in three different areas the plant cover and 10 cm of top soil was removed in 1986 after an analysis (Hult-Sernander-Du Rietz method) of the vegetation in a central, fixed plot (SO x 50 cm) and an examination of the flora in the nearest surroundings (< 10 m).In each of the following years (1987-91) the recolonizating vegetation of the bared plots was analysed again. After one year an almost closed vegetation was already established in most of the plots. The new vegetation consists mostly of immigrating previously found species but often with another cover value. A small number of the original species are still absent after five years. A smaller number of the species in the new vegetation are intrusive, and most of these species are coming from the nearest surroundings. In the first five years all recolonization is by means of diaspores, and the diversity increases in the last years. The paper discusses returning, disappearing and new intrusive species with background in their way of dispersal of diaspores. The conclusion is that in 1991 a succession is still -but slowlygoing on and that a totally stable vegetation possibly never will be established.

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