No abstract

Contrary to the other functions of multi-purpose reservoirs, recreational use is not associated with a tangible social value, which hinders the search for new balances among optimal uses of water that will likely be needed under climate change. The objective of this study is to analyze visitation behavior and its patterns at a large-scale reservoir system on the Vltava River to quantify the total social benefits associated with recreation in monetary terms and to suggest how the magnitude of estimated recreation welfare relates to hydro-energy benefits, which are in usual practice taken much more into account than recreation in the strategic management of water dams. The elicited average consumer surplus per person and trip is EUR 55.7, which yields a total yearly recreation value of EUR 34 billion (ranging between 22 and 57). When compared to, e.g., the social value of hydro-energy generation, the actual yearly recreation welfare represents 1/3 of this nowadays more prioritized use. The results of the study bring new information for water management bodies that has been missing up to now, and they bring new arguments for reaching socially optimal water use in the strategic and operational management of the cascade of dams. From this perspective, the actual strategic relative prioritization of these two reservoir functions at the pilot site may be viewed as rational.

Trees provide a wide variety of ecosystem services to society and form the character of the environment and landscape. The analyses of tree populations and their resistance to changing conditions related to climate change typically focus on urban tree communities or forest trees. Similar studies on non-forest trees in the open landscape are largely missing; even the evidence on tree species abundance and distribution is sporadic. The article aims to expand the current evidence by a large-scale study on roadside trees in the Czech Republic. Using an extensive dataset that covers 91.2% of the total tree population along roads in nine NUTS3 regions, we assess the state and observed practices in selecting tree genera for roadside planting and discuss the implications for sustainable tree planning and management. Our survey documented 133,169 tree individuals belonging to 116 species and 40 genera. The results show that 75% of the total roadside plantings along second-class motorways and first-class roads are represented by seven main genera of deciduous trees (Acer, Fraxinus, Tilia, Malus, Betula, Populus, and Quercus), the distribution of which is similar across most Czech regions. New plantings have shifted only a little from the original species distribution. Traditional roadside species are becoming a more popular choice among new plantings, and the effort not to let the invasive trees outgrow into the mature stage is apparent. Most of the original and newly planted species are relatively suitable for emerging risks related to climate change. To achieve more sustainable patterns in roadside tree species composition in the future, especially the susceptibility of some commonly planted roadside tree species to emerging pests and diseases (e.g., Fraxinus excelsior) and to unfavorable site conditions typical for roadside tree stands (Tilia cordata) is of relevance to tree managers. The relative abundance of tree genera was proven to be similar in most studied regions, which makes the recommendations equally relevant for roadside tree managers across the country.