Epsilon Archive for Student Projects

Abstract

Urbanization is a worldwide trend that has changed the natural water cycle. Today, storm-water in cities is considered a problem that, amongst other things, causes damage to infrastructure. With a changing climate with predicted more frequent extreme rainfall, immense pressures will be put on the storm-water systems that are already in need of reconstruction and maintenance today. Alternative solutions are required to handle the storm-water and reduce the pressure on the storm-water systems. One of these solutions are rain gardens. These constructions are lowered plant beds with a coarse substrate and vegetation that delays, infiltrates and purifies the storm water.

In this thesis work, the plant material in 8 rain gardens in Vellinge was inventoried approximately 2 years after establishment. The vegetation is an essential component in the rain garden construction, but there is little information about suitable plantspecies.

Which species that tolerate living in rain gardens needs to be developed further.

The main results of this study are the following:
The species used in the rain gardens that showed good establishment and are potentially good species for future use in rain gardens are Acer freemanii 'Alumna Blaze', Pinus heldreichii, Cornus sericea 'Kelseyi', Alchemilla mollis, Calamagrostis x acutiflora 'Karl Foerster', Carex panicea and Allium stipitatum 'Mount Everest'.

Species that should be examined further for use in rain gardens are Rhus aromatica 'Grow Low' and Narcissus 'Thalia'. Rhus aromatica 'Grow Low' should be adapted to this kind of environment and an obvious choice biotope-adapted plant use. Narcissus 'Thalia' has shown good establishment, but some individuals were lost. On the other hand, it grows early in the spring when nothing else has begun to grow and contribute with the aesthetic value.

Further studies should be done on Iris pseudacorus to see if it tolerates growing in rain gardens.

The infiltration of the rain gardens is still high, although it differs between the different rain gardens.