Functional attributes of the landscape surrounding the Temelin nuclear power plant (Czech Republic)

Abstract

The aim of this study is to show the importance of permanent vegetation in landscape in terms of surface temperature. Indicators of key landscape functions (surface temperature, wetness, and biomass content) were monitored from May to September in five catchments with different vegetation covers. The analysis of Landsat satellite data illustrates that areas with a higher proportion of forest and wetlands provide a more balanced temperature-moisture regime throughout the growing season, reduce average and peak temperature, and enhance humidity. In these areas, solar radiation is transformed into latent heat, which leads to landscape cooling. This process indirectly leads to the reduction of soil erosion, loss of water, oxidation of organic matter, and nutrient export. A landscape characterized by a balanced temperature-moisture regime also has a higher ability to bind and retain pollutants. Artificial drainage and loss of natural wetlands are common across most of our agricultural landscapes. Drained fields have a low capacity to retain water, nutrients, and pollutants. Where cereal crops dominate, the temperature-moisture regime evolves through different stages. With the exception of the early growth, maturity and senescence are characterized by high average and peak temperatures, high temperature variations, and low humidity. As illustrated by the relationship existing between water electrical conductivity and cation concentration in relation to land cover, such landscapes have a lowered ability to retain chemical elements and pollutants. The sites that were object of our survey are situated within the emergency planning zone of the Temelín nuclear power plant, in order to demonstrate how our analytical approach may be applied to radiation risk management. IntroductionRetention of water and matter are important characteristics of the landscape, especially where some man-made hazards and risks may occur, i.e. the emergency planning zone (EPZ) of a nuclear power plant. Ripl (2003Ripl ( , 1995 described how plant stands and wetlands retain water, nutrients, other soluble matter, and suspended solids. Procházka, Brom, and Pechar (2009) demonstrated that the amount of discharged water and matter losses from a drained pasture are substantially higher than those from wet meadows and a forested catchment. Evapotranspiration (ET) reduces water discharge from soil. The amount of water evaporated from a given land surface can be an order of magnitude higher than an average water discharge. For example ET consuming 250 W m −2 corresponds to evaporation of 100 l s -1 km 2 . Consumption of solar energy by ET results in local cooling and can be monitored. Procházka et al. (2006) showed that ecosystems of low water and matter discharge had lower surface temperature than those of high water and matter discharge. In this article, we use surface temperature as an indicator of water