|Hydrological monitoring is a fundamental basis for the correct understanding of the water cycle in the landscape and for the description of related hydrological processes. First reliable quantitative information about volumes of water present in the land water cycle were obtained in the 17th century but more intensified effort related to the description of water cycle in various natural conditions commenced in the second half of 20th century. Since UNESCO launched the International Hydrological Decade (IHD) 1965 – 1974 many hydrological research basins have been established and focused on hydrological processes at a basin scale. Only in well-defined small basins, where there are high-quality measurements, is it possible to investigate the complexities of combined physical, chemical and biological processes. Small hydrological research basins provide therefore inter-disciplinary observatories. Realizing the relevance of environmental changes (e.g. climate and land-use changes), the value of long-term measurements in small research basins has become more important. Nowadays, there is a notable shift in the types of observed variables from the common ones characterising the amount of water stored or particular water fluxes (precipitation, discharge, groundwater level) to the detailed description of the water origin (namely in terms of its age and origin).|
The Institute of Hydrodynamics has a long-term experience with a study of hydrological processes in a small catchment scale – the fundamental research of the hydrologic cycle in Volyňka catchment (Southern Bohemia, Czech Republic) was established by IH in the framework of IHD. The continuous hydrological monitoring of the Liz experimental catchment (http://ne-friend.bafg.de/servlet/is/17796/Otava.pdf) has been established since 1975 and it is a part of the Euromediterranean Network of Experimental and Representative Basins (ERB).
At present, complex hydrological, soil-hydrological and geochemical monitoring is operated in the experimental catchments Liz in the Landscape Protected Area in the Šumava Mts. (0,99 km2) and Modrý potok in the National Park of the Giant Mts. (2,62 km2) (https://www.lter.cz/horske-povodi-modreho-potoka). Further, three locations situated in the National Park of the Šumava Mts. differing in the vegetative cover are monitored. In order to quantify the amount of water and pollutants incoming to the ecosystems by the deposition from wind driven low clouds and fogs, monitoring systems were created in the Šumava Mts., Jizerské hory Mts., and Giant Mts.
A great attention is paid to the detailed monitoring of the potential and amount of water in the vadose zone of the soil profile. For the forest canopy water balance estimation, the automatic systems for the monitoring of the open area precipitation, throughfall, transpiration flux and soil surface evporation were established in the Šumava Mts.