Modernization of agricultural drainage as a new trend in improving the quality of drainage water

Agricultural drainage is a frequent feature of the landscape, which significantly affects its water regime, when it drains water from land according to pre-set parameters. As a result of not only due to climate change, its modernization to controlled drainage with sub-irrigation is being researched, which would allow for greater control over water management and increase the quality of drainage waters. The aim of the bachelor's thesis is to assess the influence of controlled drainage on reducing nitrate nitrogen (N-NO3) in drainage waters. Based on the literature, the thesis evaluates the changes that the outflow regulation will cause in the reduction of N-NO3. The evaluation of the research showed that the effect of controlled drainage through the prevention of runoff does reduce losses of N-NO3, but its effect on reducing N-NO3 concentrations in drainage waters is not demonstrable. However, limitation of drainage runoff brings an additional risk regarding the spread of N-NO3 to the environment through increased percolation and surface runoff. The location of the site and its environmental conditions (soil type, meteorological situation, agricultural management, etc.) are essential factors for N-NO3 reduction. Future research should focus more on the other runoff pathways (percoation, surface..