In recent years, programmes aimed at improving environmental conditions in river valleys within urban spaces have been initiated in many of the European Community countries. An example is the project “Revitalization of Urban River Spaces – REURIS” which was implemented in 2009-2012. Its main aim was to revitalize a part of the valley of the River Ślepiotka in Katowice. One of the tasks of the project was a comprehensive treatment to combat invasive plant species occurring in this area, carried out by using a combination of chemical and mechanical methods. Chemical treatment involved the application of herbicide mixtures, and mechanical treatment included, among others, mowing and/or removal of the undesirable plants. The work focused primarily on reducing the spread of two species of the Impatiens genus: I. glandulifera and I. parviflora, and the species Padus serotina, Reynoutria japonica and Solidago canadensis. Currently, the maintenance works on this section of the river are performed by the Urban Greenery Department in Katowice, which continues the elimination of invasive plants, according to the objectives of the REURIS program. In 2012 the Department of Botany and Nature Protection at the Faculty of Biology and Environmental Protection started to monitor the implementation and the effects of the implemented actions for elimination and participated in the action of removal of selected invasive plant species: Impatiens parviflora and Reynoutria japonica within specific areas. These actions led to a reduction in the area occupied by invasive plants and a weakening of their growth rate and ability to reproduce.
The paper discusses issues about the revitalisation of spoil tips, socio-economic polarisation and social exclusion in the field of municipal recreational activities based on an example of the largest post-industrial region in Europe – the Ruhr area in Germany. Revitalisation of brownfield areas very often leads to the creation of leisure facilities of various types (with a range of entrance fees) and because of this it may mitigate, or exacerbate, the severity of these negative phenomena. In the Ruhr area there are 104 spoil tips of different origins (mine tips, slag heaps, rubbish dumps), sizes and shapes (from conical heaps, through table mountains shaped tips and intentionally shaped for landscape tips, to major tips) and state of preservation. The research has shown that it is possible to use the majority of these spoil tips in the Ruhr area (87 of them) as leisure facilities as they have been changed into green areas, parks, playgrounds, locations for sports activities and tourist attractions after their restoration. Furthermore, they are mostly accessible free of charge and may serve a wide range of people – from locals to visitors, from children to senior citizens etc., regardless of their income. As such they may mitigate the socio-economic polarisation tendencies in the region.