DAPHNE Institute of Applied Ecology

Lakes and reservoirs that are used for water supply and/or flow regulations have usually poorly developed littoral macrophyte communities, which impairs ecological potential in terms of the EU Water Framework Directive. The aim of our study was to reveal controlling factors for the growth of littoral macrophytes in a storage reservoir with fluctuating water level (Lipno Reservoir, Czech Republic). Macrophytes occurred in this reservoir only in the eulittoral zone i.e. , the shoreline region between the highest and the lowest seasonal water levels. Three eulittoral sub-zones could be distinguished: the upper eulittoral with a stable community of perennial species with high cover, the middle eulittoral with relatively high richness of emergent and amphibious species present at low cover values, and the lower eulittoral devoid of permanent vegetation. Cover and species composition in particular sub-zones were primarily influenced by the duration and timing of flooding, followed by nutrient limitation and strongly reducing conditions in the flooded organic sediment. Our results stress the ecological importance of eulittoral zone in reservoirs with fluctuating water levels where macrophyte growth can be supported by targeted management of water level, thus helping reservoir managers in improving the ecological potential of this type of water bodies.

The European landscape is under pervasive attack of massive land use changes, such as agricultural intensification, urbanization and land abandonment. These changes resulted in population decline of birds living in open habitats. Despite a good understanding on the effects of these driving forces on bird populations, effective conservation actions are difficult to conduct as these forces are closely connected with socioeconomic development of particular countries and thus almost impossible to reverse. It is hence necessary to conserve refuge sites with a limited influence of these negative factors. We surveyed birds in 42 abandoned military training sites (AMTS) in a central European country, the Czech Republic, and we have found these sites are valuable, and to date overlooked, refuges for bird conservation. Birds of high conservation concern and open habitats birds (such as Miliaria calandra, Saxicola torquata or Lullula arborea) were more abundant in AMTS than predicted by their total population size in the Czech Republic. The most important characteristics predicting attractiveness of AMTS for birds of conservation concern were low altitude, low proportion of forest/dense scrubland, high proportion of sparse scrubland/bare ground and large area. Former military activity was beneficial for declining open habitat birds by maintaining moderate disturbance levels, which are rarely found elsewhere in current landscapes. Owing to reduction of armed forces across Europe AMTS provide continental-wide network of high-quality sites for bird conservation. Nevertheless, AMTS are subject to pressure from building activities or loss of openness due to overgrowth of forest or scrub plant communities.

The present area of European wetlands is only a fraction of their area before the start of large-scale human colonization of Europe. Many European wetlands have been exploited and managed for various purposes. Large wetland areas have been drained and reclaimed mainly for agriculture and establishment of human settlements. These threats to European wetlands persist. The main responses of European wetlands to ongoing climate change will vary according to wetland type and geographical location. Sea level rise will probably be the decisive factor affecting coastal wetlands, especially along the Atlantic coast. In the boreal part of Europe, increased temperatures will probably lead to increased annual evapotranspiration and lower organic matter accumulation in soil. The role of vast boreal wetlands as carbon sinks may thus be suppressed. In central and western Europe, the risk of floods may support the political will for ecosystem-unfriendly flood defence measures, which may threaten the hydrology of existing wetlands. Southern Europe will probably suffer most from water shortage, which may strengthen the competition for water resources between agriculture, industry and settlements on the one hand and nature conservancy, including wetland conservation, on the other.

The results of spatial modelling based on various climatic change scenarios predict shifts in the geographical ranges of species. Theoretically, a species can spread into new areas if the local habitat composition meets its ecological requirements. Therefore, habitat change in an unfavourable direction should inhibit climatically induced range shifts in some species. We tested this prediction using data on breeding bird distribution in the Czech Republic, a small central European country. We selected 28 species whose northern range limits are in central Europe and compared their distribution in the Czech Republic between 1985–1989 and 2001–2003. From these species, we identified 10 affected by habitat changes, such as a loss in environmental heterogeneity or agricultural intensification, using a local literature survey. As a group, the 28 species did not show any significant changes in their breeding distribution. However, those species affected by habitat change significantly restricted their distribution, whereas the remaining species not affected by habitat change increased their distribution. We suggest that the increasing occupancy of species not affected by habitat change could be caused by climate change. However, climate cannot overshadow the negative impacts of land-use changes on the distribution of species affected by habitat change. Therefore, such species could be seriously threatened: they might not be able to track their climatic optima if future climate change proceeds in tandem with the destruction of their habitats.