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Instruments for precipitation measurement from history to the present
Lipina, P. ; Procházka, J. ; Tesař, Miroslav
The precipitation amount is one of the most important meteorological elements. It is of fundamental importance for the creation of climatological characteristics, it is the basis of the water balance and the primarily monitored element in the forecasting and warning service. Precipitation measurement has been burdened with many uncertainties for a long time and is therefore consistently given due attention.\nThe first measurement of precipitation in Europe dates back to the 17th century. Regular but not complete measurements of precipitation at Prague's Klementine observatory began in 1752 (continuous series since 1804), in Brno in 1803. In 1817, M.A. David wrote the first guide for observing the weather in Bohemia, published in German, intended for volunteer observers. The activities of institutions and various associations, such as the Prague Klementinum, the Natural Research Society in Brno, the Central Institute for Meteorology and Earth Magnetism and others, had a fundamental influence on the establishment of meteorological stations and precipitation measurements. The Hydrographic Commission for the Kingdom of the Czech Republic and its hydrometric section were founded in 1875 under the leadership of F. J. Studnička E. Purkyně was responsible for the significant expansion of precipitation measurement at that time as part of the construction of a network of forest precipitation measuring stations. \nFor more than 200 years, rain gauges and precipitation measurements have been developed. The Metra 886 manual rain gauge, which has been used for a long time in the Czech lands, was developed according to the Austrian model of prof. Kostlivý. Since 1995, the automation of rainfall measurement was started, first with tipping bucket raingauges, which are gradually being replaced by weighing raingauges. Alternative methods of measuring precipitation are being tested in\nremote and forested areas. This post tries to bring the history, standards and development of precipitation measurement in our country at least as a guide.
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Changes in the ratio between a new snow depth and seasonal precipitation in mountainous and submontane regions of the Czech Republic
Procházka, J. ; Lipina, P. ; Šustková, V. ; Tesař, Miroslav
Snowfall and snow cover formation is an important aspect of the colder part of the year in the Czech Republic and Central Europe. Snow cover is important from the point of view of climatology, hydrology, ecology and recreation, and therefore economic. In addition to precipitation, the amount of new snow depends mainly on the air temperature. With gradual warming, it can be assumed that with a similar total precipitation, the proportion of precipitation in the form of snow and the ability to form snow cover will decrease. In order to evaluate the mentioned changes, the ratio of the seasonal amount of new snow in cm and total precipitation in mm, Sn/P (cm/mm) was used in this paper. For the analysis, data from the CHMI database for two normal periods 1961–1990 and 1991–2020 were processed for selected mountain and foothill meteorological stations in the Czech Republic. The period from November to April was assessed as a cold part of the year for this purpose, when a new snow cover is more likely to form. The results of the study showed that the Sn/P ratio decreased in the period 1991–2020 compared to the period 1961–1990.
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The importance of field wetlands in agricultural landscapes
Šumberová, Kateřina ; Vymyslický, T. ; Fabšičová, Martina ; Fránková, Markéta
Field wetlands represent an extremely valuable biotope in agricultural landscapes, not only in terms of water management, but also in terms of biodiversity of various groups of organisms. Species living in these habitats survive adverse periods in the form of seeds, spores and eggs in the soil, many of them belonging to endangered groups of organisms. Our research has yielded in new findings of rare vascular plant species, as well as interesting findings of diverse species of micro- and macroscopic algae. Among the most important findings are some thermophilic and slightly halophilic vascular and algae species, whose occurrence in our country is mainly linked to southern Moravia. Seventeen plant species from the current Red List were found, three species in the critically endangered category (C1: Hibiscus trionum, Pulicaria dysenterica, P vulgaris), six species in the severely endangered category (C2: Lythrum hyssopifolia, Malva pusilla, Rumex tenophyllus, Schoenoplectus tabernaemontani, Veronica anagalloides), five species in the endangered category (C3: Centaurium pulchellum, Cyperus fuscus, Lemna trisulca, Lotus tenuis, Veronica catenata) and five rarer species requiring attention (C4: Bolboschoenus laticarpus, B planiculmis, Butomus umbellatus, Limosella aquatica, Schoenoplectus lacustris). The vegetation at the study sites could be classified into five syntaxonomic classes: Lemnetea, Potametea, Isoëto-Nanojuncetea, Bidentetea tripartitae and Phragmito-Magnocaricetea. Vascular plants were represented by several ecological groups: annual wetland plants, perennial species of reed beds and wet disturbed grasslands, hydrophilous weeds and ruderal species, and aquatic plants. Macroscopic algae were represented primarily by filamentous green algae of the genera Cladophora, Spirogyra and Oedogonium, and to a lesser extent by the genus Vaucheria spp., and by cyanobacteria (Nostoc spp.). The representatives of the genus Chara inhabited wetlands with longer periods of inundation. Diatoms (Achnanthidium, Amphora, Gomphonema, Navicula, Nitzschia, Pinnularia, Surirella and Tryblionella) were the most quantitatively represented and species-rich group of microalgae in the studied wetlands, followed by the genera Colacium, Euglena and Trachelomonas, by green algae (Desmodesmus), and by cyanobacteria (Homoeothrix and Phormidium).There was a high variability in the number of vascular plants and overall species composition, as well as in the representation of different algal groups and their species richness. Large changes were evident between and within years.
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