Comparison of scenarios for the Vistula river, Poland

Abstract

The Vistula River is considered one of the most valuable rivers in Western and Central Europe. The Vistula floodplain area forms an extensively managed landscape, with high nature values and biodiversity. This riverine landscape is rapidly undergoing changes in land use and spatial developments. The floodplain area from Warsaw to Płock was selected for an assessment of ecological impacts through scenario analysis. Five scenarios were developed which contain elements of expected or possible developments. Effects of each scenario on indicative fauna species were analyzed with the computer model LARCH, an expert system for scenario analysis and policy evaluation. The analysis shows that fragmentation presently does not threaten the favourable conservation status of the species assessed. Most of the species have either nearly sustainable, sustainable or highly sustainable networks. The analyses conducted for the 16 species characteristic for the Vistula valley show potential threats of infrastructure development reflected in scenario 1, "Maximum river regulation and infrastructure development". Scenario 1 showed pronounced effects on species dependent on steep banks and sandbanks. Scenario 3, "Renaturalisation" showed positive effects for most species, notably species of steep banks and sandbanks. Scenario 5, "Reforestation" showed positive effects on species depending on forest habitat, while species typical for meadows decreased. The designation of the 2 Natura 2000 areas has strongly reduced the options for building dams in the area, as interventions are only allowed if they have no significant effects on the area. An evaluation of developments that affect the biodiversity and spatial cohesion (fragmentation) of habitats is essential to come to balanced developments, taking into account both environmental and societal needs. Stakeholder involvement and scenario modelling should be widely used in the process of decision making for spatial development. © 2007 Springer Netherlands.